Artiles
Open Access
Article
27 August 2026Physicochemical Characterization of the High-Altitude Lakes in Northern Pakistan: Implications for Water Resource Management
Lakes provide a wide range of ecological, cultural, and economic benefits and prime opportunities for recreation, tourism, and livelihoods in the Upper Indus Basin (UIB). In the wake of growing anthropogenic actions and climate change impacts, an appraisal of the lake water quality is essential to determine the health of the ecosystem and assist resource conservation initiatives in the region. An attempt has been made to establish a preliminary physicochemical baseline for eight high-altitude lakes in the UIB, Pakistan, to characterize their spatial hydrochemical variability and identify potential water quality concerns in the region. At the time of sampling, the lakes exhibited a slightly alkaline condition with pH ranging between 7.7 and 8.2 (mean 8.0). The lower alkalinity detected in the lakes, like Sheosar (42 mg/L), may indicate limited buffering capacity and more sensitivity to nutrient pulses or potential acidification. Nitrate-N concentration was low in most lakes, with many below detection limits. The Gibbs diagram indicated seven samples in the rock dominance zone, i.e., chemical weathering of rocks as the major factor contributing ions to the lake water, while in one sample, i.e., Borith Lake, evaporation-crystallization was the main source of dissolved chemical ingredients. The Spearman correlation analysis indicated a higher positive relationship (r > 0.9) between Ca and Mg, likely due to carbonate rock weathering. The observed variations in the water quality parameters may have significant effects on both the ecosystem and human health, necessitating further research and future attention. In-depth research on glacio-hydrological dynamics and limnology can support sustainable management and conservation of the freshwater ecosystems in the region.
Open Access
Article
27 August 2026Functionalized Polyurethane as a Hole Transport Layer for Quantum Dot-Sensitized Solar Cells with Higher Open-Circuit Voltage and Fill Factor
A functionalized polyurethane-based hole transport layer (HTL) for quantum dot-sensitized solar cells (QDSSCs) has been developed by tailoring the redox behaviour of segmented polyurethane. The successful incorporation of ionic moieties into the hard segment was confirmed by Fourier-transform infrared (FTIR) and Nuclear magnetic resonance (NMR) spectroscopy. Sulfonation significantly improved the polymer’s electrical conductivity, electrochemical activity, and optical properties, thereby enabling efficient hole transport through favorable work-function alignment and reduced interfacial energy barriers between the photoactive layer and the Ag counter electrode. Ultrasmall spherical CuInS2 quantum dots with an average size of 3.15 nm were synthesized using a capping-assisted method and characterized by X-ray diffraction (XRD), UV-Vis spectroscopy, and Transmission electron microscopy (TEM). The HOMO-LUMO and valence/conduction band energy levels, determined by cyclic voltammetry and UV-vis spectroscopy, revealed favorable energy level alignment for efficient charge separation and hole extraction. QDSSCs were fabricated with the architectures FTO/TiO2/CuInS2/SPU-2/Ag and FTO/SnO2/TiO2/CuInS2/SPU-2/Ag. The introduction of an SnO2 interfacial electron transport layer enhanced electron extraction by improving the energy band alignment with TiO2, resulting in an increase in photocurrent density from 0.74 to 2.12 mA·cm−2. The corresponding devices exhibited high open-circuit voltages of 0.89 and 0.75 V, fill factors of 67% and 56%, and power conversion efficiencies of 0.45% and 0.89%, respectively. These results demonstrate that the functionalized polyurethane HTL, combined with a SnO2/TiO2 bilayer electron transport layer (ETL), provides an effective strategy to improve charge transport and enhance the photovoltaic performance of CuInS2-based QDSSCs.
Open Access
Review
27 August 2026Turbulent Transition Criteria: From Reynolds Experiment to Modern Numerical Methods
Turbulent transition refers to the complex flow phenomenon of laminar flow evolving into turbulence, and the criteria for judging transition constitute a core research topic in fluid mechanics, computational fluid dynamics, flow experiments, and engineering applications. This study systematically reviews the evolutionary framework of transition criteria over the past century, ranging from the empirical Reynolds number rule, linear stability theory, and the engineering en method, to semi-empirical correlations, the intermittency factor γ model, energy gradient theory, and state-of-the-art numerical criteria based on direct numerical simulation (DNS) and large eddy simulation (LES). Specialized stability criteria for non-parallel flows such as Taylor–Couette flow and Dean flow are sorted out, and the evolutionary paths, theoretical foundations, and applicable working conditions of low-turbulence natural transition and high-disturbance bypass transition are clarified. The progress of existing research is summarized, with critical bottlenecks identified, including high-Reynolds-number transition, three-dimensional coupled complex flows, and poor generalization of data-driven models. The applicable scopes and inherent defects of diverse transition theories are compared: energy gradient theory explains the instability mechanism of finite-amplitude perturbations; the intermittency factor model dominates industrial numerical simulations; and high-fidelity numerical simulation serves as the core tool for uncovering micro transition mechanisms. Four major future research directions are proposed: unified multi-scale theoretical frameworks, efficient computational fluid dynamics (CFD) algorithms, data-driven prediction models, and engineering applications for novel fluid machinery, delivering theoretical support for transition prediction and flow control.
Open Access
Article
27 August 2026The Use of Ultrasound Diagnostic Method and Histological Technique to Detect Pathologies of the Internal Organs and Skin of Sturgeon Species
To restore the stocks of sturgeon fish species in a depressed state, it is necessary to form broodstocks in hatchery farms. The technology of forming stocks in industrial conditions is far from perfect due to the low quality of breeders. The aim of this work was to identify the frequency of occurrence of anomalies and diseases of sturgeon internal organs using the method of ultrasound scanning and histological study. Two-dimensional black-and-white image, Doppler, elastography, and panoramic scan were used. Regular sonographic studies of abdominal organs, carried out in 2018–2025 at 20 fish farms, revealed a number of common pathologies and diseases in generative tissue: cystosis and polycystosis, fatty degeneration, underdevelopment and torsion of testes, neoplasm, hermaphroditism, sludge in the gallbladder, ascites, and others. The maximal number of individuals with disorders in the development of internal organs reached 67.9%, an average is 24.8%. Two stages of cystic degeneration of the ovaries were characterized by ultrasonic scanning. A significant increase in the number of females over 9 years old, with replacement of generative tissue with connective tissue (13.6%), was noted. The nature of ‘ink spots’ on the skin of Siberian sturgeon natural populations was studied. Malignant skin neoplasms were detected, and treatment routes were outlined.
Open Access
Review
26 August 2026Small Extracellular Vesicles-Mediated Immunoregulation in Melanoma Progression and Its Implications for Immunotherapy
Melanoma is a highly lethal malignant skin tumor. While immune checkpoint therapy has notably improved patient prognosis, formidable challenges, including drug resistance and immune-related adverse events, remain unresolved. Small extracellular vesicles (sEVs), pivotal mediators of intercellular communication, exert critical roles in melanoma immunoregulation and immune escape. This review focuses on the immunomodulatory effects of sEVs derived from melanoma cells and immune cells (including natural killer cells, macrophages, and dendritic cells) within the tumor immune microenvironment. It further delineates their regulatory mechanisms governing distinct immune cell populations, as well as their intricate associations with immunotherapy resistance. Additionally, the potential of sEVs and their cargo molecules as therapeutic targets and diagnostic biomarkers is explored, offering a theoretical foundation for overcoming immune checkpoint inhibitor resistance and advancing the development of novel melanoma immunotherapies.
Open Access
Article
26 August 2026Economic and Environmental Analysis of Photovoltaic-Thermal Systems Integrated with Shea Butter as a Phase Change Material in Nigeria
The literature documents the economic and environmental evaluations of conventional phase change materials (PCMs), such as paraffin wax, used in photovoltaic-thermal (PV-T) systems. Nonetheless, there is limited evidence of bio-based PCM applications within PV-T systems. This study investigates the economic and environmental aspects of employing shea butter as a bio-based PCM in a PV-T setup. The photovoltaic-thermal system integrated with shea butter was designed using the Transient Simulation System (TRNSYS). The shea butter system showed superior economic performance, with a levelized cost of energy (LCOE) of US$0.131/kWh, compared with US$0.146/kWh for the paraffin wax system. Its energy costs were also lower than those of the grid and diesel generation in Nigeria. However, the payback period was longer than that of traditional PV systems. Environmentally, shea butter has a global warming potential (GWP) of 0.615 kg CO2e, significantly lower than that of paraffin wax (3.75 kg CO2e).
Open Access
Article
26 August 2026Research on the Mooring System of Fishery-Photovoltaic Complementary Integrated Structure Under Wave Action
The influence of mooring system parameters on the hydrodynamic characteristics of waves of the Fishery-Photovoltaic complementary integrated platform formed by installing aquaculture cages on the Huaneng ‘Huanghai No.1’ floating photovoltaic platform is studied. It systematically investigates the influence of mooring system parameters on the wave-induced hydrodynamic performance of the integrated platform. A fully coupled numerical model for the integrated platform-mooring system is established using the OrcaFlex11.4c software. The reliability of the proposed numerical method is validated against the Cylindrical Floating Production, Storage and Offloading (CFPSO) wave basin model test and the net cage flume test. Through 17 simulation cases with gradient mooring radius settings, this study elucidates the response pattern of the mooring system as it transitions from a catenary configuration to a taut configuration. The results indicate that a relative mooring length of approximately 0.73 corresponds to the critical threshold. At this threshold, mooring stiffness rises abruptly, platform motion responses are markedly suppressed, cage volume variation is mitigated, and mooring line tensions remain within a controllable range. This mooring radius achieves an optimal trade-off among platform motion performance, mooring tension safety, and aquaculture stability. Further increasing the mooring radius yields only marginal improvements in motion response and cage volume performance, while causing a notable rise in mooring tension and a sharp decline in system cost-effectiveness. This study provides a theoretical foundation for the design of mooring systems for deep-sea fishery-photovoltaic complementary integrated platforms.
Open Access
Article
25 August 2026Elucidation of Diatom Impregnated with Iron Nanoparticles as a Bio-Stimulator in Early Growth and Development of Rice
Merging nanotechnology with biology, diatoms reveal an extraordinary capacity to fabricate iron nanoparticles (INPs) while simultaneously acting as nutrient carriers for crops. The marine diatom Halamphora subturgida was employed for the first time to synthesize INPs and evaluate their application as a nanophycofertilizer (NPF) for rice (Oryza sativa L.). The diatom facilitated both intra- and extracellular formation of spindle-shaped nanoparticles (70–100 nm) as confirmed by UV–Vis, DLS, TEM, SEM-EDAX, FTIR, and fluorescence analyses. Biochemical profiling revealed dynamic metabolic shifts during nanoparticle synthesis, with transient increases in pigments, proteins, and lipids followed by their decline, while iron and carbon content rose steadily. Antioxidant enzyme assays indicated early oxidative stress followed by metabolic adaptation, underscoring the diatom’s resilience as a biofactory. When applied to rice seedlings, the INP-loaded diatoms significantly outperformed diatoms or nanoparticles alone, increasing shoot length by approximately 45%, root length by 50%, fresh biomass by 18%, chlorophyll content by 42%, iron accumulation by nearly twofold, and silica uptake by about 43% compared with the untreated control. These synergistic effects highlight the dual role of diatoms as both stabilizers and nutrient carriers, delivering iron in a highly bioavailable form while simultaneously contributing silica for structural strength. The findings position diatom-mediated nanofertilizers as sustainable alternatives to chemical fertilizers, offering a multifaceted strategy to boost crop vigor, nutrient density, and early-stage resilience in rice.
Open Access
Article
21 August 2026What Do Indigenous Perspectives from the Americas on Nonhuman Beings Tell Us Considering Artificial Intelligence, Humanoid Robots, and Synthetic Life Forms?
This essay examines the understanding of artificial intelligence, humanoid robots, and biohybrid systems—or synthetic life forms—from an indigenous perspective in the Americas. Building on a critical examination of the ontological turn, this essay explores the significance of relationality for indigenous peoples beyond concepts such as animism or new animism. The ontological turn does not establish substantive connections to the modern world regarding these entities. However, techno-animism seems to suggest an ontological approach to artificial intelligence, though it does not explain how ontology develops in practice for humans and nonhumans alike. Based on reflections on indigenous perspectives in the Americas, this essay attempts to develop an alternative foundation for ontology regarding artificial intelligence, humanoid robots, and biohybrid systems or synthetic life forms—entities that are more than just tools or machines.
Open Access
Review
21 August 2026How Does the Mechanical Structure of a Dexterous Hand Drive Embodied Intelligence
Robotic dexterous hands, as the primary end-effectors through which embodied agents interact with the physical world, directly determine grasp stability, manipulation accuracy, environmental adaptability, and human–robot interaction safety. Research on dexterous hand mechanical structures has expanded rapidly and become increasingly interdisciplinary, so conventional narrative reviews can no longer capture its knowledge base, research drivers, and the evolution of hotspots. A systematic framework that combines bibliometric quantification with mechanism-oriented synthesis is therefore needed. This study presents a bibliometric review of dexterous hand mechanical structures based on Web of Science Core Collection publications from 2016 to 2025, combining bibliometric statistics, collaboration-network analysis, keyword co-occurrence, cluster analysis, and trend synthesis to reveal the field’s research landscape, intellectual structure, and technological evolution. Publications increased steadily, rising from 64 in 2016 to 252 in 2025, with marked acceleration after 2022. China leads in publication volume, whereas the United States, Germany, and the United Kingdom show strong citation impact and international collaboration. Core journals concentrate on robotics, mechatronics, sensing, soft robotics, and rehabilitation engineering, and keyword evolution shows a shift from prosthetic hands and basic mechanism design toward compliant structures, soft actuation, tactile perception, and dexterous manipulation. Based on keyword clustering, three principal research streams are identified: body configuration and degree-of-freedom (DoF) evolution, drive and transmission structure design, and soft/compliant structure expansion. The central challenge of dexterous hand design is no longer the accumulation of DoFs but the coordinated optimization of DoF allocation, actuation mapping, contact stability, and compliant adaptation under strict constraints of space, energy, and reliability. Tendon-driven, internally integrated, and underactuated architectures emphasize lightweight dexterity, precision control, and adaptive grasping, respectively, while soft continuum, rigid–soft hybrid, and variable-stiffness structures are reshaping dexterous hands from rigid execution mechanisms into physically intelligent interaction systems. Overall, the field has entered a stage of interdisciplinary system integration, with its core mission shifting from building complex mechanical hands to constructing perceptive, adaptive, and controllable end-effectors. Future work should strengthen task-oriented structural optimization, hybrid actuation, rigid–soft coupling, integrated flexible sensing and closed-loop control, and unified performance evaluation, accelerating the transition from laboratory prototypes to standardized assessment and large-scale deployment.
