Artiles
Open Access
Article
04 August 2026Determining Maximum Allowable Concentrations of Selenium and Iron Nanoparticles in Hediste diversicolor as Sturgeon Live Feed
This study aimed to determine the acute dietary toxicity and Maximum Allowable Concentration (MAC) of selenium (Se-NPs) and iron (Fe-NPs) nanoparticles for the ragworm (Hediste diversicolor). This worm is a critical live feed source in sturgeon aquaculture, directly influencing the health and growth of larvae and juveniles. However, the safe dietary levels of these nanoparticles for the ragworm itself, and consequently the risk of trophic transfer to sturgeon, remain unknown. Determining safe dietary levels of nanoparticles in this organism is therefore essential for ensuring the safety of the entire sturgeon feed chain. Worms were exposed to six concentrations (0, 100 μg/kg, 1, 10, 100 mg/kg, and 1 g/kg diet) of each nanoparticle for 96 h in three replicates. Throughout the experiment, aeration was provided, and worm behavior was monitored. Cumulative mortality was recorded at 24, 48, 72, and 96-h intervals. Data were recorded in Microsoft Office Excel 2019, and statistical analysis was performed using SPSS software (Version 26). Data were analyzed by Probit analysis with a 95% confidence level. The LC10, LC50, and LC90 values for Se-NPs were calculated to be 291.2, 989.8, and 1690 mg/kg, respectively. For Fe-NPs, these values were 924.3, 3300, and 5700 mg/kg, respectively. Using a standard Safety Factor (SF) of 10, the calculated MAC are 98.98 mg/kg for Se-NPs and 330.0 mg/kg for Fe-NPs. This study establishes critical toxicity thresholds for Se-NPs and Fe-NPs in ragworm. The findings provide essential data for developing safe feeding protocols in sturgeon aquaculture, helping to prevent potential nanoparticle toxicity transfer through contaminated live feed and ensuring sustainable sturgeon production.
Open Access
Article
04 August 2026Contrasting Wave Power Intensity and Resource Quality in the Northwest Pacific: Variability, Availability, and Extreme Load Risk
Using 45 years of six-hourly ERA5 reanalysis data from 1979 to 2023, this study evaluates the spatial mismatch between theoretical wave-power intensity and practical resource quality across the Northwest Pacific. Resource quality is characterized by temporal variability, threshold-based availability, resource persistence, extreme-event exposure, and wind-sea/swell composition. The mid- to high-latitude storm belt and the Kuroshio Extension exhibit the highest mean and upper-tail wave power, but their resources are strongly concentrated in winter, with monthly coefficients of variation of approximately 0.5–0.7, seasonal variability indices commonly exceeding 0.7, and elevated extreme-event exposure. By contrast, subtropical and western-boundary transition regions generally have lower mean wave power but steadier availability and lower relative risk. Stable and low-risk regions are also more swell dominated, whereas high-resource and high-risk conditions are associated with larger wind-sea contributions. These results indicate that variability and risk can offset the benefits of high mean wave power and may increase operational costs. Maximum wave power, therefore, does not necessarily imply the highest resource quality, and the proposed framework provides a basis for basin-scale wave-energy pre-screening.
Open Access
Review
04 August 2026Groundwater Systems, Aquifer Characterization, and Sustainability Challenges in Nigeria: A Scoping Review of Hydrogeological and Geophysical Investigations (2000–2026)
Groundwater represents one of the most important freshwater resources in Nigeria and serves as a major source of water for domestic, agricultural, and industrial activities. This scoping review synthesizes existing knowledge on groundwater systems, aquifer characterization, hydrogeophysical investigations, groundwater quality, and sustainability challenges across different hydrogeological environments in Nigeria. The review adopted the PRISMA-ScR framework and analyzed peer-reviewed studies published between 2000 and 2026, retrieved from Scopus, Web of Science, Google Scholar, ScienceDirect, and SpringerLink databases. The findings revealed substantial hydrogeological variability associated with the Basement Complex terrains, sedimentary basins, Coastal Plain Sands, and alluvial aquifer systems. Vertical Electrical Sounding (VES), Electrical Resistivity Tomography (ERT), hydrochemical analysis, GIS integration, and remote sensing emerged as the dominant groundwater investigation techniques. The review further identified increasing groundwater quality deterioration resulting from salinity intrusion, industrial pollution, oil spill contamination, excessive groundwater abstraction, and climate variability. Coastal aquifers within the Niger Delta, Lagos, and Akwa Ibom regions were found to be particularly vulnerable to seawater intrusion and hydrocarbon contamination. Despite increasing groundwater studies, major gaps remain in long-term monitoring, integrated hydrogeophysical investigations, and national groundwater database development. The study emphasizes the need for integrated groundwater management, sustainable policy frameworks, climate-resilient groundwater assessment approaches, and interdisciplinary research strategies to support long-term groundwater sustainability and water security in Nigeria.
Open Access
Review
03 August 2026Life by Assembly Line1: A Century-Long Quest to Build Life—And Define It
Synthetic biology increasingly pursues the construction of engineered biological systems, yet the field lacks operational categories for interpreting claims of “life creation”. Rather than asking whether life has already been created in the laboratory, this article argues that synthetic biology requires a pragmatic framework that distinguishes modification, reconstruction, assembly, and autonomous synthesis of biological systems. Building on a historical analysis of recurring life-creation claims throughout twentieth-century biology, we develop a taxonomy that situates contemporary synthetic biology and xenobiology along a continuum of increasing engineering depth. Current achievements—including genome rewriting, orthogonal translation systems, and expanded genetic codes—represent a deep reconstruction of living systems, but do not yet constitute fully autonomous synthetic life. To clarify these distinctions, we introduce several conceptual tools: the Pasteurian Wall separating living from non-living systems, the Genetic Firewall as a biosafety principle for engineered organisms, and an Expanded Chemoton framework that provides an engineering-oriented operational definition of life based on metabolic autonomy, informational closure, and evolvability. Together, these elements allow experimental systems to be positioned along a functional continuum from sophisticated biochemical artifacts to genuinely alternative living systems. By replacing metaphor-driven narratives with operational categories, this framework aims to strengthen conceptual clarity, experimental comparability, and governance of emerging synthetic life technologies.
Open Access
Article
03 August 2026Green Synthesis of NiFe2O4 Nanoparticles Using Combretum Indicum Leaf Extract for the Synthesis of 2-Aryl Benzimidazole
The versatile applications of nitrogen-containing heterocycles in different industries have engendered a lot of research. Benzimidazole derivatives, as isostructural pharmacophores of naturally occurring active biomolecules, are popular chemotherapeutic drugs. The present study focuses on a green methodology for the synthesis of NiFe2O4 nanocomposite using Combretum indicum leaf extract, and for the synthesis of 2-aryl benzimidazole derivatives via the condensation of aromatic aldehydes and O-phenylenediamine. The synthesized catalyst was characterized through various analytical techniques, including FT-IR, XRD, SEM, TEM, and BET. It has several advantages, including a rapid reaction at room temperature, easy work-up, high product yield, simple purification, and a reusable catalyst. The catalyst was reused for up to six consecutive cycles, with the yield decreasing only marginally from 95% (fresh catalyst) to 89% (sixth reuse).
Open Access
Article
03 August 2026Design of Micro/Nano-Lamellar C4AcH11 and Hydrotalcite in Alumina-Spinel Castables: Enhanced High-Temperature Damage Resistance
In the present study, lamellar hydrates were designed via curing regimes and additives. Structural and high-temperature fracture behavior analyses were employed to elucidate the influence of initial lamellar hydrates on microstructural evolution and thermal stress resistance at elevated temperatures. Key findings reveal that: Pure CAC cured at 25 °C for 24 h predominantly forms metastable CAH10 and C2AH8, whereas under the two-step curing regime, the hydration products are granular C3AH6 and lamellar AH3. Incorporating CaCO3 and MgO under two-step curing promotes the simultaneous generation of micro/nano-lamellar C4AcH11 and Mg-Al Hydrotalcite (M-A-H). The enhanced extent of hydration and pore-filling effect of M-A-H refines matrix porosity, increasing the volume fraction of 5–100 nm pores and elevating the fractal dimension (Ds). This microstructural optimization improves bonding strength, as evidenced by an 82% increase in demolding strength in the designed samples compared with the R samples. C4AcH11 and M-A-H serve as reactive CaO and MgO sources, respectively, facilitating the interlocking distribution of in-situ CA6 and MgAl2O4 at 1600 °C and optimizing pore structure. The hierarchical pore structure and refined crystals synergistically enhance thermal stress resistance by increasing crack deflection, dissipating energy, and improving plastic deformation capacity.
Open Access
Article
31 July 2026Non-Destructive Testing of Multilayer Composite Materials
Multilayer composite materials are used in advanced engineering as a material for heavy-duty products. However, the use of multilayer composite materials requires consideration of their inherent specific properties, such as anisotropy of mechanical characteristics and the possibility of the presence of hidden defects in the form of discontinuity of the material along the interfaces of individual layers (laminations). Evaluation of interlayer failures throughout the life cycle is critical to reducing composite product safety risks. In this article, the analysis of interlayer defects in composites employs comprehensive control, including several non-destructive testing methods: visual inspection, ultrasonic flaw detection, active thermography, and numerical modeling. Interlayer defects obtained as a result of low and high-speed impact on multilayer composite materials are considered. It has been found that the results from numerical modulation of interlayer defects and from non-destructive inspection of defects such as laminations, obtained by different methods, agree satisfactorily.
Open Access
Article
31 July 2026The Lanthanum-Modified Zeolite for Efficient Removal of Glyphosate: Adsorption Behaviors and Mechanisms
Glyphosate is one of the most extensively used organophosphorus herbicides; however, its excessive application and environmental residues have severely threatened aquatic ecosystems and human health. In this study, a highly efficient lanthanum-modified zeolite (LMZ) adsorbent was synthesized via a hydrothermal method, and its adsorption behaviors and underlying mechanisms for glyphosate removal were systematically investigated. LMZ exhibited exceptional adsorption performance over a broad pH range of 3.0–7.0, achieving a maximum adsorption capacity of 217.39 mg/g. The adsorption process was well described by the Langmuir isotherm and pseudo-second-order kinetic models, indicating a monolayer chemisorption process. Notably, LMZ demonstrated remarkable adsorption selectivity and excellent regenerability, maintaining a high adsorption capacity even after five consecutive adsorption-desorption cycles. In practical application assessments with simulated wastewater, glyphosate removal efficiency exceeded 90% at an adsorbent dosage of 7.5 g/L. Furthermore, dynamic column experiments confirmed that LMZ could maintain effective continuous adsorption, highlighting its substantial application potential for treating glyphosate-contaminated wastewater. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopic characterizations revealed that this outstanding adsorption capability is primarily driven by inner-sphere complexation induced by ligand exchange at the La-OH active sites.
Open Access
Article
31 July 2026International Policies in the Face of Climate and Human Impacts Occurring in the Sahel
The Sahel is a strip of land that begins in Mauritania and ends in Eritrea. It is approximately 5400 km long and varies in width from 100 to 1000 km. Based on different historical perspectives, the Sahel can be considered to encompass a total of five countries. Subsequently, other countries have been added that, due to their geographical and climatic characteristics, can be considered Sahelian. The Sahelian countries emerged after 1960, the year in which decolonization began, but also the instability that was initially triggered by military coups aimed at destabilizing power. Later, climatic instability, famine, political instability, terrorism, and other factors have also played a role. This essay focuses on analyzing the actions and current activities of certain actors in the Sahel.
Open Access
Article
31 July 2026Fine-Scale Taxonomic and Functional Diversity Patterns Inform Within-Site Sampling Strategies for Benthic Macroinvertebrates in an Alpine Stream
Fine-scale habitat heterogeneity can generate marked short-distance variation in alpine-stream benthic macroinvertebrate assemblages, yet routine surveys often characterize a site using five Surber-net replicates collected within an approximately 100 m reach. We analyzed 99 quantitative samples collected at 10 m intervals along a 1 km reach of Qingbixi Stream on Cangshan Mountain, Dali, Yunnan, China, to relate taxonomic and functional diversity patterns to within-site sampling design. The samples contained 69 taxa and 15,034 individuals. Across 20 consecutive 50 m sections, turnover accounted for 70.9% of mean total pairwise taxonomic beta diversity, whereas nestedness accounted for 96.3% of mean total functional trait-state beta diversity. Taxonomic dissimilarity increased weakly but significantly with longitudinal distance. In ten simulated nominal 100 m sampling units, five spatial replicates detected an average of 82.9% of the locally observed taxon pool; completeness increased to 87.4% with six replicates and 94.6% with eight. These results support five replicates as a practical baseline for routine community characterization, while more intensive or microhabitat-stratified sampling is preferable when near-complete taxon detection or fine-scale beta-diversity assessment is required.