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Molecular Docking Analysis of Bioactive Compounds from Wurfbainia compacta Against
No full textCandida albicans is an opportunistic pathogen that causes oral and systemic candidiasis, especially in immunocompromised individuals. Natural medicines obtained from medicinal plants offer compelling alternatives for addressing virulence factors in C. albicans, including adhesins and enzymes secreted for biofilm development. This study examined molecular docking (using AutoDock Vina software) to test and evaluate the binding affinities of four natural compounds—2,7-Dioxa-tricyclo[4.4.0.0(3,8)]deca-4,9-diene, dodecanoic acid 2,3-bis(acetyloxy)propyl ester, hexadecanoic acid ethyl ester, and ethyl iso-allocholate—against the virulence proteins ALS1, ALS3, SAP4, SAP5, and SAP6 of C. albicans. Docking and physicochemical, pharmacokinetic, and toxicity assessments were conducted to ascertain their potential as antifungal drugs. Ethyl iso-allocholate exhibited the highest binding affinity, especially towards SAP6 (− 8.4 kcal/mol), suggesting that is a promising antifungal agent. Among the tested compounds, ethyl iso-allocholate demonstrated the strongest and most consistent binding interactions with key virulence proteins of C. albicans, particularly SAP6, indicating its potential as a promising lead molecule for the development of novel antifungal therapeutics targeting pathogenic mechanisms
Phytoplankton biodiversity for water quality assessment based on saprobic index in Oransbari – South Manokwari
No full textThe biodiversity of phytoplankton plays a role in aquatic ecosystem. The saprobic index is one of the methods used to determine water quality using the composition of phytoplankton. This study aimed to examine phytoplankton biodiversity for water quality assessment based on saprobic index in Oransbari Bay, South Manokwari Regency. The study was conducted from September to November 2024, and water samples were collected using a plankton net (20μm mesh size) from 6 (six) study sites located in Oransbari Bay. Water samples were then examined for phytoplankton diversity and saprobic index. The results showed that the composition of phytoplankton reached 13 classes that distributed over 8-12 classes during the three months observations for all study sites. The number of species found varied 54-80 between September and November; while the species diversity in study sites was 1.1 - 3.4 categorized from moderate to high diversity, which determine good water conditions. The saprobic index of the water quality in Oransbari Bay was 0,63, categorized as light ß-mesosaprobic and the trophic saprobic index was the oligosaprobic level
Fine details in solar flare ribbons
No full textContext. Flare ribbons serve as chromospheric footprints of energy deposition resulting from particle acceleration during magnetic reconnection. Their fine-scale structure provides a valuable tool for probing the dynamics of the flare reconnection process.
Aims. Our goal is to investigate the fine-scale structure of flare ribbons through multiple observations of flares, utilising data obtained from the Atmospheric Imaging Assembly (AIA) and the Swedish 1-m Solar Telescope (SST).
Methods. The aligned AIA and SST datasets for the three solar flares were used to examine their overall morphology. The SST datasets were specifically used to identify fine-scale structures within the flare ribbons. For spectroscopic analysis of these fine-scale structures, we applied machine-learning methods (k-means clustering) and Gaussian fitting.
Results. Using k-means, we identified elongated features in the flare ribbons, termed as ‘riblets’, which are short-lived and jet-like small-scale structures that extend as plasma columns from the flare ribbons. Riblets are more prominent near the solar limb and represent the ribbon front. Riblet widths are consistent across observations, ranging from 110−310 km (015−041), while vertical lengths span 620−1220 km (083−166), with a potential maximum of 2000 km (267), after accounting for projection effects. Detailed Hβ spectral analysis reveals that riblets exhibit a single, redshifted emission component, with velocities of 16−21 km s−1, independent of the viewing angle.
Conclusions. Our high-resolution observations of the three flare ribbons show that they are not continuous structures, but rather are composed of vertically extended, fine-scale substructures. These irregular features indicate that the reconnection region is not a smooth, laminar current sheet, but rather a fragmented zone filled with magnetic islands (blobs or riblets), consistent with the theory of patchy reconnection within the coronal current sheet
No TiO detected in the hot-Neptune-desert planet LTT-9779 b in reflected light at high spectral resolution
No full textLTT-9779 b is an inhabitant of the hot-Neptune desert and one of only a few planets with a measured high albedo. Characterising the atmosphere of this world is the key to understanding the processes that dominate in reducing the number of short-period intermediatemass planets that create the hot-Neptune desert. We aim to characterise the reflected light of LTT-9779 b at high spectral resolution to break the degeneracy between clouds and atmospheric metallicity. This is key to interpreting its mass-loss history, which might illuminate how it kept its place in the desert. We used the high-resolution cross-correlation spectroscopy technique on four half-nights of ESPRESSO observations in 4-UT mode (16.4 m effective mirror) to constrain the reflected-light spectrum of LTT-9779 b. We did not detect the reflected-light spectrum of LTT-9779 b although these data had the expected sensitivity at the level 100 ppm. Injection tests of the post-eclipse data indicated that TiO should have been detected for a range of different equilibrium chemistry models. Therefore, this non-detection suggests TiO depletion in the western hemisphere, but this conclusion is sensitive to temperature, which affects the chemistry in the upper atmosphere and the reliability of the line list. Additionally, we were able to constrain the top of the western cloud deck to Ptop, western < 10−2∙0 bar and the top of the eastern cloud deck to Ptop, eastern < 10−0∙5 bar, which is consistent with the predicted altitude of MgSiO3 and Mg2SiO4 clouds from JWST NIRISS/SOSS. While we did not detect the reflected-light spectrum of LTT-9779 b, we verified that this technique can be used in practice to characterise the reflected light of exoplanets at high spectral resolution when their spectra contain a sufficient number of deep spectral lines. Therefore, this technique may become an important cornerstone of exoplanet characterisation with the ELT and beyond
An enhancement of a possibilistic regression model using conditional-based non-symmetric fuzzy numbers
No full textThis paper introduces the proposed Possibilistic Fuzzy Linear Regression (PPFLR) model, a novel approach to fuzzy linear regression which enables the identification of the most accurate predictions by precisely defining the spread of non-symmetric fuzzy numbers, allowing for a more nuanced and realistic representation of uncertainty in both input-output variables compared to traditional models. The proposed model leverages confidence intervals at various significant level to determine the smallest spread across non-symmetric fuzzy number areas, there by resolving this issue for each data component. Furthermore, a comprehensive set of criteria for evaluating the effectiveness and suitability of the PPFLR-model across diverse fuzzy data analysis scenarios. The practical application and efficacy of the PPFLR-model is demonstrated through implementation on real-world car dataset, particularly in predicting car prices. It performs well in each of the three cases: Pentagonal Fuzzy Number, Hexagonal Fuzzy Number, and Octagonal Fuzzy Number, obtaining average values of 23102.72, 22512.12, and 23209.66 respectively, demonstrating the model's accuracy and robustness
Measuring and evaluating the multi-compartment vehicle routing problem in dynamic environment using two hybrid meta-heuristics approaches
No full textThis paper introduces the Dynamic Multi-Compartment Vehicle Routing Problem (DMCVRP)
as a new variant of the classic Vehicle Routing Problem (VRP). The DMCVRP combines two
existing extensions: the Multi-Compartment Vehicle Routing Problem (MCVRP) and the Dy-
namic Vehicle Routing Problem (DVRP). To analyze and evaluate this variant, the DMCVRP
is decomposed into a sequence of standard MCVRPs. A mathematical model is presented
based on the MCVRP formulation, ensuring that the total customer demand for each product
is fully delivered by the same vehicle, while respecting individual compartment capacities.
Given the NP-hard nature of the DMCVRP, we propose and compare two hybrid meta-
heuristic algorithms: Hybrid Simulated Annealing (HSA) and Hybrid Adaptive Variable
Neighborhood Search (HAVNS). The experimental evaluation is performed on a set of dy-
namic benchmark instances, and sensitivity analysis is conducted on key parameters such as
frequency and magnitude of change.
The results show that HAVNS outperforms HSA under high-frequency dynamic conditions,
while HSA performs better than HAVNS when the frequency of change is low. These findings
highlight the strengths and trade-offs of both approaches in solving complex dynamic routing
problems with multi-compartment constraints
Profit analysis and equilibrium customer joining strategies for single server triple orbit retrial queue
No full textThis paper appears to investigate the optimal joining strategies of arriving customers under different scenarios in the single-server Markovian queueing systems with three types of retrial orbits: standard, deluxe, and business class. Customers who arrive at the system and find the server busy can join one of the retrial orbits based on their preference and paying capacity. The standard orbit is assumed to be the cheapest, and customers who want to pay less would choose this option. Customers whose paying capacity is higher would join the deluxe orbit, while those who can afford the high cost would join the business-class orbit. The probability-generating function technique is applied to solve the steady-state difference equations and derive the steady-state probabilities and other important system metrics for a probability distribution. The cost-reward function is framed and analyzed based on the joining strategies of the arriving customers. The arriving customers would decide whether to join the queue or not based on the cost-reward structure. The cost-reward function may reflect the trade-off between the profit for those joining the queue and the waiting cost in the queue. The numerical experiment is also done by taking a numerical example and comparing the results for the fully unobservable, partially unobservable, partially observable, and fully observable. The development of equilibrium and social strategies enabled to make a detailed study on the behavior of customers subject to profit. This study can provide insights into the behavior of customers in queuing systems and inform the design and management of such systems in various applications, such as service operations, transportation, manufacturing, or production, etc
Dossier « Les professionnels de la montagne face aux transitions socio-environnementales » – Les agents d’espaces naturels face aux changements socio-environnementaux et institutionnels : le cas des génépis dans le parc national du Mercantour
No full textLes législations mises en œuvre dans les parcs nationaux évoluent au gré de changements institutionnels et socio-environnementaux. Ces territoires, en interaction avec les acteurs qui les utilisent ou les gèrent, peuvent être considérés comme des socio-écosystèmes. Les agents des parcs nationaux jouent un rôle central dans ces systèmes, en tant que sentinelles des dynamiques écologiques et sociales du parc, tout en ayant pour mission d’appliquer des réglementations peu dynamiques et parfois décalées. La gestion d’une plante patrimoniale comme le génépi attise des visions contradictoires entre utilisateurs et gestionnaires. Nous nous intéressons ici plus spécifiquement à la manière dont les agents du parc national du Mercantour vivent les changements affectant le socio-écosystème de « cueillette des génépis », que ce soit l’évolution des populations de génépi, des pratiques de cueillette, de leur métier ou de l’institution « parc national ». Les entretiens soulignent la diversité de vécus au sein de ce territoire, reflétée par les dysfonctionnements de la réglementation de cueillette que chaque agent identifie
Direction of screw insertion for internal fixation plate in distal femoral osteotomy: Evaluation using axial computer tomography imaging
No full textPurpose: In distal femoral osteotomy (DFO), using longer distal screws in fixation plates may improve stability. This study examined the insertion direction of three distal screws at the horizontal cross-section to determine if posterior angulation enables deeper placement. Methods: Forty-seven varus knees that underwent DFO were included (medial closed-wedge DFO [MCWDFO], 30 knees; lateral closed-wedge DFO [LCWDFO], 17 knees). Postoperative plain CT images were obtained from a plane parallel to the three distal screws, with the most distal screw designated as A, the anterior of the second distal row as B, and the posterior of the second distal row as C. For each case, a curve passing through the center of the bony cortex on the cross-section parallel to each screw and over its entire length was drawn, and the curve and the lower edge of the screw were projected onto a graph. The maximum angle at which the lower edge of each screw touches the intercondylar region without interfering with the intercondylar region was designated as (AnA), (AnB), and (AnC) for A-, B-, and C-screws, respectively. The angle between the line connecting the insertion points of the B- and C-screws on the plate and the tangent line to the medial and lateral bony cortex was designated as (AnP). Results: In the MCWDFO group, the mean values for each parameter were AnA, 10.9 ± 5.4; AnB, 27.0 ± 4.2; AnC, 9.2 ± 3.4; and AnP, −2.6 ± 6.9. In the LCWDFO group, the mean values for each parameter were AnA, 18.2 ± 6.9; AnB, 30.4 ± 7.1; AnC, 16.1 ± 7.2; AnP, −0.2 ± 6.1°. Conclusions: The medial surface is inclined compared to the epicondylar axis and posterior condyle, usually resulting in plate positioning that is parallel to the placement surface. The optimal screw insertion from the anterior to posterior was generally achieved; however, there was still room for posterior angulation margins of 9–11° for A- and C-screws and approximately 27° for the B-screw. In contrast, the lateral surface is flatter with less inclination, causing anterior plate placement and wider posterior angulation – approximately 16–18° for A- and C-screws and 30° for the B-screw – allowing a greater range of posterior swing than the medial side
Linear approximations of large deviations: cubic diffusion test
No full textWe propose a method for approximating the large deviation rate function of time-integrated observables of diffusion processes, used in statistical physics to characterize the fluctuations of nonequilibrium systems. The method is based on linearizing the effective process associated with the large deviations of the process and observable considered, and is tested for a simple one-dimensional nonlinear diffusion model involving a cubic drift. The results show that the linear approximation compares well with the exact rate function, especially in the large fluctuation regime, and that its accuracy is related to the way the linearized process localizes in space. Possible extensions and applications to more complex diffusion models are proposed for future work