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This article deals with the existence of solutions to a boundary value problem for the Caputo type modification of the Erdélyi-Kober fractional differential equations. Our primary results are demonstrated by combining the fixed point theorems of Darbo and Mônch with the approach of measures of noncompactness. Furthermore, an example is provided to highlight the applicability of our findings. [ABSTRACT FROM AUTHOR]

Aquatic macroinvertebrates are an important component of biodiversity in stream Ecosystems. Conserving and enhancing freshwater biodiversity is important for maintaining ecosystem integrity and sustainability. This requires understanding how the composition of biological communities is influenced by environmental factors at different scales. Factors such as water chemistry, temperature, flow, and land use can all affect the distribution and abundance of different species in freshwater ecosystems. The North of Algeria has a complex hydrographic network, but the inventory of aquatic macroinvertebrates community remains incomplete. This study aimed at compiling an inventory of the macroinvertebrate inhabiting the aquatic ecosystems of each stations in Chréa National Park (province of Blida, Algeria). The results were used to answer two questions: (i) macroinvertebrate composition and richness in these protected ecosystems? (ii) Which taxon or group of taxa is the most dominant?. Different sampling methods (Surber, kick samplers and artificial substrate) were used depending on the characteristics of the sites chosen. The sampling was carried out during three months (February to April, 2021). It was analyzed and identified 1345 organisms belonging to 41 macroinvertebrate families. The system showed high richness and diversity of organisms in response to water quality. The presence of Leptophlebiidae, Baetidae, Heptageniidae and Chironomidae with high abundance of the families showed the potential as biological indicators of a clean ecosystem. To collect the samples, It was used a surber sampler 1 mm mesh every week, with six repetitions in each station, from February to April, 2021. After cleaning and removal of debris. we proceeded by a pre-sorting in morpho-species, then a sorting of the different taxa was carried out in the laboratory. the organisms were identified using a stereoscopic microscope and identification keys. The community structure including abundance, richness and composition was statistical different between stations. [ABSTRACT FROM AUTHOR]

Investigating the fascinating world of natural fibers, where Syagrus romanzoffiana fibers (SrFs) are promising substitutes for glass and synthetic fibers in composite materials, is more than interesting. The improvement of SrFs through an environmentally friendly treatment employing sodium bicarbonate (NaHCO₃) at different concentrations (5 %, 10 %, 20 %, and 30 % by weight) over various durations (24, 72, and 168 h) is the subject of this study. The objective is to provide a sustainable and economical approach to enhancing fiber characteristics. Comparisons were made between treated and untreated fibers and fibers from semi-arid and humid regions to evaluate geographical influences. Key findings include considerable enhancements in tensile properties: a 58 % rise in Young's modulus and a 69 % rise in traction stress for fibers treated with 20 % NaHCO₃ for 72 h. The stretching at fracture of these treated fibers was measured at 1.04 ± 4.49 %. The treated fibers also showed an increased crystallinity index of 71.61 % and a crystal size of 2.38 nm. Fourier-transform infrared spectroscopy revealed the chemical modifications from the treatment. Thermogravimetric analysis (TGA) indicated thermal stability up to 327 °C and a kinetic activation energy of 53.84 kJ/mol, compared to 62.72 kJ/mol for untreated fibers. The study highlights an environmentally friendly approach to material development by showcasing the potential of treated SrFs in lightweight biocomposite applications. This study provides valuable information on the TGA/pyrolysis of SrFs at 10 °C/min for potential bioenergy production, including assessing environmental impact, opportunities concerning sustainable resource management, and integration with other renewable energy systems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Research on natural fibers as greener substitutes for synthetic ones has surged in response to the growing need for sustainable materials. An underutilized natural resource, Chamaerops humilis trunk (ChT), is the subject of this study's extraction and characterization process. The work examines these fibers' possible uses in biocomposites by examining their structural, physicochemical, and mechanical characteristics. Numerous characterization techniques were used to evaluate ChT fibers (ChTFs) thoroughly, including density measurement, diameter determination, analysis of the fibers' moisture content, X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, thermal analysis, water absorption tests, and tensile testing. Experimental results show that ChTFs possess an average density of 0.97 g/cm 3 , an average diameter of 562 ± 60 μm, a moisture regain ranging from 7.94 to 8.63 %, an average linear density of 9.338 Tex, heat resistance to 225 °C and a mean traction resistance of 45.08 ± 9.92 MPa. Such findings underscore the significance of comprehending the ChT's mechanical characteristics to enhance fiber-reinforced composites and explore their possible uses in the textile sector besides their promising reinforcements in biocomposites and as a source of biomass for renewable bioenergy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A designer of sustainable biocomposite structures and natural ropes needs to have a high confidence interval (95% CI) for mechanical characteristics data of performance materials, yet qualities for plant-based fibers are very diverse. A comprehensive study of the elements that enhance the performance of biocomposites or sustainable ropes created from vegetable fibers is necessary. The current study included five groups with varying numbers (N) of tests of 20, 40, 60, 80, and 100 on the mechanical characteristics at room temperatures. The purpose of this study was to determine how changing N affects the mechanical properties of sisal yarn. These properties include its strength, Young's modulus, and deformation at rupture. A significance testing program including more than 100 tests was performed. Owing to the heterogeneity of the plant yarn, each group received more than 20 samples at a gauge length (GL) of 100 mm. The tensile strength characteristics of sisal yarns produced a wide range of findings, as is common for natural fibers, necessitating a statistical analysis. Its dispersion was explored and measured using the statistical methods. The Weibull distribution with two parameters and a prediction model with a 95% confidence level for maximum likelihood (ML) and least squares (LS) were used to investigate and quantify its dispersion.