Artiles
Open Access
Article
22 June 2026Influence of Nutrient Enrichment and Temperature on Aquatic Invertebrate Communities in a Tropical Riverine System in Kenya
One of the major concerns in freshwater ecosystems is nutrient enrichment from human sources, which causes significant effects on aquatic biodiversity and ecological functioning. This study, therefore, investigated the order and family levels of Odonata, Diptera, and Coleoptera responses to nutrient enrichment along River Kiminini, Trans-Nzoia County, Kenya. Field sampling was conducted from July to September 2023. Duplicate water samples were taken from ten sampling stations labelled (S1–S10), twice a month for three months. The concentrations of nitrate–nitrogen and phosphate–phosphorus were measured calorimetrically using standard procedures; the Ascorbic Acid method for phosphates–phosphorus and the Brucine method for nitrates–nitrogen. A spectrophotometer was used to measure absorbance. A standard kick net was used at each station to collect the macroinvertebrates (Odonata, Diptera, and Coleoptera). Using an updated taxonomic key, the macroinvertebrate samples were sorted and identified to their family level under a dissecting microscope, and abundance counts were made. Direct field observations were used to record human activity at each station. The R programming language was used to conduct all statistical analyses. The water quality status for each station was determined using the Nutrient Pollution Index, which was calculated based on ecologically relevant nutrient thresholds. The Nutrients Pollution Index scores ranged from 9.66 (S5) to 17.2 (S3). All the stations were greater than 6, indicating very high pollution levels and a significant risk of eutrophication. At the family level, Dytiscidae, Coenagrionidae, and Lestidae were abundant in less polluted stations and fewer in highly polluted stations. For instance, Coenagrionidae had the highest numbers in station S1 (32) and declined drastically in the highly polluted station S9 (3). The same trend was observed for Lestidae, with the highest numbers in stations S1 and S2 (21) and declining in station S9 (1). Dytiscidae also had higher numbers in the relatively less polluted station S7 (10) and lowest in the highly polluted station S3 (1). On the other hand, Chironomidae was observed to be tolerant to organic pollution. Chironomidae had their highest numbers in station S9 (30) and declined in moderately cleaner stations S5, S6, and S8, which had a similar record of 6 organisms. According to the findings, it is necessary to enhance biomonitoring and guide riverine management plans under nutrient stress and increasing water temperatures by incorporating functional and taxonomic diversity into water quality assessments.
Open Access
Article
22 June 2026Utilization of Post-Mortem Oocytes for In Vitro Embryo Production for Preservation of Adapted High Genetic Value Germplasm of Jersey Cattle
Assisted reproductive techniques offer a valuable tool for rescuing deceased germplasm for the establishment of replacement stock as well as conservation of valuable/threatened germplasm. The techniques assume greater importance for the preservation of the adapted dairy germplasm raised through decades of up-gradation using exotic semen, especially in the ecologically sensitive Himalayan region. Gamete retrieval from deceased animals is of special importance in countries where cattle slaughter is prohibited, thus rendering the abattoir-derived gonad availability impossible. The present study envisages the developmental competence of oocytes retrieved from dead Jersey cows. From 112 ovaries, derived from 56 deceased cows, 847 COCs were recovered and grouped by post-mortem interval (PMI): 0–6 h (Group I) versus 6–12 h (Group II). The proportion of Grade A & B oocytes did not differ significantly between the groups (65.4% vs. 59.0%). In vitro maturation (IVM) was significantly higher in group I (80.6 ± 2.0%) than in group II (46.2 ± 2.7%; p < 0.0001). With unsexed semen, cleavage was higher in Group I than Group II (55.7 ± 5.9% vs. 38.3 ± 7.9%; p = 0.012); while blastocyst yield showed only a non-significant trend in favour of Group I. Sex-sorted semen reduced cleavage and blastocyst rates overall, with no significant difference between groups. On days 7–8, 44 blastocysts from Group I and 2 from Group II were vitrified. Survival after thawing was 90.9% (40/44) and 100% (2/2), respectively. The results demonstrated that post-mortem ovaries from naturally deceased Jersey cows can supply developmentally competent oocytes suitable for IVEP, though demanding further technical refinements to be at par with the results obtained from oocyte retrieval from live animals using the OPU technique.
Open Access
Article
18 June 2026Ethnogenesis Reconstruction in the Population of South Siberia and Tuva Using Data on N-M178 and O-M175 Polymorphisms
Some important aspects of the history of ethnogenesis in South Siberia have been reconstructed using data on two Y-haplogroups: N-M178 (n = 113) and O-M175 (n = 24). In Tuvans, who make up two-thirds of the indigenous South Siberian population, these haplogroups constitute 20% of the gene pool, and their branches form well discriminated ethno-specific clusters within the phylogenetic network of 37 Y-STR marker haplotypes. N-Y24317(xB499) is thought to have arrived in Tuva from Mongolia or Northwest China during the Bronze Age or Early Iron Age. According to our hypothesis, the spread of N-Y16319(xY16223) and N-Y16223(xZ35328, F2288) with DYS385 = 11,11 is linked to the development of the Ulug-Khem culture in Tuva around 2100 YBP as a result of the growth and expansion of the Xiongnu. Three branches (N-Z35328, N-F2288, N-Y16223(xZ35328, F2288) with DYS385 = 11,13) widespread among the Turkic-Mongolian populations are rare in Tuvans. The arrival of these haplogroups, as well as O-M175, in Tuva is associated with the Medieval Mongol expansion. However, the Turkic-Mongolian contribution of O-M175 to the Tuvan gene pool is insignificant: the ancestors of most Tuvan lineages might have been the Han forcibly moved by the Yuan Empire to the settlements of craftsmen and farmers located in what is now the territory of modern Tuva.
Open Access
Article
16 June 2026Modeling and Simulation of Express Delivery Using Quadrotor UAVs
In this study, the trajectory planning and control problem for quadrotor unmanned aerial vehicles (UAVs) in logistics-oriented delivery scenarios. A smooth trajectory generation method based on spline curves is proposed to ensure continuous, stable, and feasible flight paths for quadrotor UAVs under dynamic constraints. The proposed method focuses on general UAV path planning rather than a specific express delivery optimization problem. A simulation platform is developed to evaluate the effectiveness of the trajectory planning and control framework, where a PID-based controller is implemented for trajectory tracking and attitude stabilization. The performance of the proposed method is validated through two representative emergency delivery scenarios, demonstrating accurate path tracking and stable flight behavior under environmental disturbances. The results indicate that the proposed framework provides a reliable simulation tool for UAV trajectory planning and control analysis, contributing to general UAV motion planning research rather than a specific delivery optimization formulation.
Open Access
Review
16 June 2026Reverse Tourism: A New Opportunity for the Sustainable Development of Rural Tourism
Against the backdrop of homogeneous mass tourism, reverse tourism, as a trend where tourists avoid popular destinations and pursue niche experiences, is reshaping the paradigm of rural tourism development. This paper systematically analyzes the connotation, framework, and feasibility of reverse tourism using comparative analysis, model derivation, and practical verification. The study reveals that reverse tourism is characterized by three key dimensions: reflection on the essence of tourism, aberration in tourist behavior, and distinction in tourist experience, forming a dynamic cycle mechanism of “willingness-behavior-experience”. Additionally, centering on tourists is crucial for constructing the analytical framework, classifying visitors based on their travel participation history, and creating a role transition matrix, which helps uncover the endogenous driving forces of tourist behavior. Furthermore, evolving tourist demands, improvements in rural public services, and the successful replication of “small yet beautiful” models have created favorable conditions for implementing reverse tourism in rural areas. Finally, the virtuous cycle of “protection-development-benefit” formed by supply-demand coupling provides a systematic solution for rural revitalization that balances ecology, culture, and economy. This paper systematically expounds the theoretical logic, mechanism, and practical path of reverse tourism as a new paradigm for rural tourism transformation, offering research conclusions with both theoretical innovation and practical guidance for promoting rural sustainable development.
Open Access
Article
15 June 2026A Co-Benefits Analytical Framework: Overlap in Protection for People and Ecosystems from Power-Generating Tidal Range Infrastructure
Tidal range power plants (TPPs) are reliable electricity generators with the la Rance TPP in France serving as an example of long-term (60+ years) s uccess. Despite their potential for energy delivery, the challenges surrounding TPP development remain substantial. High initial investment and concerns about environmental impacts on marine ecosystems have made it difficult to progress major proposals. With rising sea levels and more frequent, intense storm surges expected to lead to greater inundation of key coastal zones, co-benefits to ecosystems and infrastructure that TPPs may offer are being reconsidered. Using the UK as a case study, we map appropriate tidal resource (>5 m tidal range), 2050 1:25 flood risk areas (1 m rise), coastal zones with conservation specification and areas of high human density. Overlap in these factors reveals specific locations in which further research would usefully estimate potential costs and benefits, socially, ecologically and financially. Viewed together, reduced flood risk to people and infrastructure, ecosystem conservation opportunity and stable energy generation may highlight the future opportunity of TPPs.
Open Access
Review
12 June 2026Beyond Oil: Molecular Breeding for Multifunctional Innovation in Oilseed Brassica
Brassica napus L., one of the world’s most significant oilseeds, is experiencing a paradigm shift from a single-minded focus on edible oil production to a multifactorial approach centered on sustainable agriculture. This review synthesizes the progress in molecular breeding, which has enabled the development of multifunctional B. napus ideotypes. We discuss the genomic plasticity of the crop, based on the genomic mosaicism and allopolyploid origin, which provides a genetic reservoir basis of diversification. Contemporary approaches such as genomic selection, marker-assisted pyramiding, and multi-omics integration are considered in terms of their ability to maximize the properties of multifaceted trait networks, breaking historical trade-offs (e.g., yield vs. quality), and providing new value-added functions. Their success is evidenced by examples, including the development of ultra-high-oil cultivars and multi-colored ornamental varieties. We also describe emerging directions, such as engineering the root architecture of dual-purpose fodder and optimizing seed oil composition with single-cell omics. These molecular tools, combined with precision agriculture technologies, enable the realization of an integrated Agriculture-Processing-Tourism framework. B. napus can move beyond being a commodity and become a personalized crop, capable of fulfilling all three functions in bringing nutritional security, bio-economic diversification, and ecological resilience, and thus, the philosophy of the Grand Food Concept.
Open Access
Review
12 June 2026PIEZO Mechanotransduction in the Cardiovascular System: Physiological Roles and Disease Implications
Mechanotransduction is essential for cardiovascular physiology, enabling cells to sense and respond to mechanical forces such as shear stress, stretch, pressure, and extracellular matrix deformation. Among mechanosensitive ion channels, PIEZO1 and PIEZO2 have emerged as critical regulators of cardiovascular mechanobiology. These large trimeric ion channels convert mechanical stimuli into calcium-dependent electrochemical signals that regulate vascular development, endothelial homeostasis, cardiac remodeling, inflammatory activation, and blood pressure control. Recent advances in structural biology, electrophysiology, and molecular genetics have substantially improved understanding of PIEZO channel architecture, mechanogating mechanisms, and downstream signaling pathways. In the cardiovascular system, PIEZO1 functions prominently in endothelial cells, cardiomyocytes, fibroblasts, erythrocytes, and vascular smooth muscle cells, where dysregulated signaling contributes to hypertension, fibrosis, cardiac hypertrophy, ischemic injury, and vascular inflammation. This review summarizes current knowledge of PIEZO-mediated cardiovascular mechanotransduction, emphasizing structural mechanisms, physiological functions, disease implications, and therapeutic potential. Emerging computational approaches, including artificial intelligence and machine learning-assisted electrophysiology, are also discussed as promising tools for advancing mechanobiological research, multiscale modeling, and precision cardiovascular medicine.
Open Access
Review
12 June 2026Overview on the Current Global Market and Sustainability of Hydrogen Supply Chain Based on China
Low carbon energy development is a solid requirement for decarbonization and carbon neutralization of the economy. Hydrogen energy is chosen for achieving a large degree of decarbonization in the fields of industrial, transport, and domestic consumptions. This paper provides an overview on the current state of global hydrogen production and demand, summarizes the momentum of green hydrogen development, and analyzes the possible roles of countries in the global hydrogen trade and cooperation. The status and costs of hydrogen production and transportation in China were systematically examined. While China has become the world’s largest hydrogen producer and consumer, it faces a major structural contradiction that the country’s hydrogen resources are unevenly distributed, abundant in the west but scarce in the east, making long-distance transport costs a key bottleneck for its domestic hydrogen energy development. To address these challenges, three strategic scenarios, including eastward hydrogen transmission, international cooperation, and efficient utilization of wind power for hydrogen production, were proposed to reach the goal that by 2050, the share of coal consumption will drop to 30%, and the share of non-fossil energy will increase to 50%. These scenarios will provide data support and strategic references for the precise positioning of China’s hydrogen market and the construction of a sustainable supply chain.
Open Access
Article
11 June 2026Processing and Characterization of Hybrid Composite Materials Made of Recycled HDPE and Mechanically Recycled Glass Fiber Thermoset Composites
Household plastic waste and industrial polymer matrix composite material scrap present two scales of problems that can lead to pollution and other environmental issues. Recycling waste and scrap has become increasingly important and has drawn tremendous attention as a promising approach to solving the growing polymer pollution issue. This study aims to create energy-efficient and scalable procedures to manufacture hybrid composite materials using household thermoplastic waste and industrial thermoset matrix composite scrap for the first time to our best knowledge, and evaluate the structural performance of upcycled fiber-reinforced composites. Recycled scrap of pultruded glass fiber vinyl ester composite (rComposite) was mechanically split with an energy-efficient process and subsequently molded with recycled household high-density polyethylene (rHDPE) waste to produce thermoset composite reinforced thermoplastic matrix (rComposite/rHDPE) composites at different rComposite contents, i.e., 20, 27, and 35 wt%. Various characterization methods, including Fourier transform infrared spectroscopy, differential scanning calorimetry, optical microscopy, and scanning electron microscopy analyses, were performed to evaluate the constituent materials and the molded composite. Mechanical testing was also conducted to evaluate the mechanical properties of the composites with different rComposite contents. It was found that the tensile and flexural properties of the rComposite/rHDPE composite increased with increasing rComposite content. There was a 256% increase in tensile strength and an 885% increase in tensile modulus for the 35%-rComposite reinforced rHDPE composite over neat rHDPE, respectively. Overall, this study presents a potential approach of recycling household plastic waste and polymer matrix composite material scrap by developing a hybrid composite material with great mechanical properties.
