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Item Artificial Intelligence-Driven Solutions for Mitigating Human–Wildlife Conflict in Biodiversity Hotspots(Sage, 2025-04-23) Ojija,Fredrick; Ogwu,Matthew C.; Ally, Juma; John,John P.; Stephano,Azaria; Felix,Nancy; Tekka,RamadhaniBiodiversity hotspots are biologically rich yet highly threatened regions that play a critical role in global conservation but often serve as epicentres of human–wildlife conflict (HWC). HWC poses major conservation and development challenges, undermining both human livelihoods and wildlife protection efforts. Artificial intelligence (AI) offers transformative tools for mitigating HWC by enhancing monitoring, prediction, and decision support. Through systematic searches of peer-reviewed and grey literature, this review analyzed 105 studies (1990–2025) from 163 screened sources, revealing that AI improved HWC monitoring (65%), predictive accuracy (47%), and community engagement (39%). AI-driven technologies such as machine learning, deep learning, and computer vision enable conservationists to process large datasets, automate species identification, and make real-time decisions. Integrated platforms like Earth Ranger and the Spatial Monitoring and Reporting Tool (SMART) use AI to manage data from rangers, camera traps, drones, and patrol logs, providing situational awareness and strategic planning tools. Furthermore, remote sensing, Geographic Information Systems (GIS), and participatory data integration offer multi-layered insights for mapping HWC zones, tracking wildlife movement, and modelling species distribution. This review highlights the application of AI in conflict detection, community engagement, and decision support while addressing challenges, limitations, and ethical concerns. It also underscores the importance of policies and future research to integrate AI with local knowledge systems, participatory governance, and adaptive conservation strategies. Overall, AI advancements are transforming HWC surveillance and enabling more proactive, equitable, and sustainable biodiversity conservation efforts worldwide.Item Hydrochemical evaluation and risk assessment of the Danube river, Hungary using Canadian indices, geochemical modeling, and simulation techniques(Springer, 2025-09-15) Saeed, Omar; Székács, András; Mörtl, Mária; Jordán , Győző; Lameck ,Azaria Stephano; Al-Mashreki,Mohammed Hezam; Abukhadra ,Mostafa R.; El-Sherbeeny , Ahmed M.; Szűcs, Péter; Eid, Mohamed HamdyThis study investigates the metals risks in the Danube River, Hungary, and identifies the natural and anthropogenic sources using geochemical modeling. In total, 76 water samples were collected from seven sites along the river during 2018. Physicochemical and heavy metals have been analyzed. Statistical tools, including Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA), were applied. Water quality was assessed using the Canadian Water Quality Index (CWQI), Metal Pollution Index (MPI), Nemerow Composite Index (NCI), Hazard Quotient (HQ), Hazard Index (HI), and Carcinogenic Risk (CR). A probabilistic approach using Monte Carlo simulation was applied to evaluate uncertainty and health risks. Geochemical modeling revealed that the river is undersaturated with minerals like gypsum, anhydrite, and halite, but supersaturated with aragonite, dolomite, and calcite. The average CWQI (44.8) and Weighted Arithmetic Water Quality Index (WAWQI, 60.1) indicate that the water is unsuitable for drinking. However, Sodium Adsorption Ratio (SAR=0.5), Sodium Percentage (Na% = 15.4), and Kelly’s Ratio (KR=0.2), suggest favorable conditions for agricultural use. The low ecological risk index (RI=0.5) and MPI (Item Catalytic Upgrading of Ethanol to 1-Butanol Biofuel Additive Using Pd/MgO-Al2O3 and Bimetallic Pd-Cu/MgO-Al2O3 Mixed Oxide Catalysts(MDPI, 2025-11-14) Makoye, Amosi; Lóny, Ferenci; Solt , Hanna E.; Cannilla , Catia; Bonura, Giuseppe; Novodárszki , Gyula; Barthos, Róbert; Valyon, József; Nagy, Tibor; Vikár , AnnaCatalytic upgrading of bioethanol via a C–C coupling reaction is a sustainable method of producing 1-butanol, a high-performance biofuel. This reaction was studied using a flow-through microreactor system with Pd/MgO-Al2O3 and bimetallic Pd-Cu/MgO-Al2O3 mixed oxide-based catalysts in a H2 carrier gas at a pressure of 21 bar and temperatures ranging from 200 to 350 ◦C. The effect of the metal promoter(s) on the hydrogen transfer reaction steps in the overall reaction was investigated. The palladium promoter significantly improved the activity and butanol selectivity across the entire temperature range. However, the yield of liquid products decreased significantly at temperatures higher than 250 ◦C, primarily because the decarbonylation side reaction of the acetaldehyde intermediate accelerated. The promoting effect of Pd was most beneficial below 250 ◦C because the decarbonylation reaction was inhibited by the reversible poisoning effect of CO on multiple Pd sites responsible for decarbonylation. Diluting the Pd phase with Cu increased liquid yields due to gradually decreasing decarbonylation activity. However, the dehydrogenation–hydrogenation activity decreased as well, as did the promoting effect on the corresponding reaction steps in the coupling reaction. Additionally, the product distribution changed dramatically, decreasing 1-butanol selectivity, because metallic Cu can catalyze the formation of ethyl acetate and ketone productsItem Modeling and optimal control of rotavirus transmission dynamics with cost effectiveness(Elsevier B.V., 2025-12-29) January, Jeremiah; Mwanga, A. Gasper; Isack E.; Kibona b,; Shaban Mbare, NyimvuaAn optimal control model for rotavirus transmission was formulated to minimize both the cost of implementing interventions and the burden of infection among children and care-givers. The model integrates five time-dependent control functions: vaccination of children (𝑢1), public health education (𝑢2), treatment of infected children (𝑢3), water treatment and sanitation (𝑢4), and hygiene promotion (𝑢5). Pontryagin’s Maximum Principle was applied to derive the necessary conditions for optimality, and numerical simulations were conducted using the Runge–Kutta method to determine the optimal time-dependent control profiles and corresponding epidemiological outcomes. Simulation results at 𝑡 = 220 days indicate a substantial reduction in rotavirus infections among children and caregivers when integrated controls are applied. The number of infected and hospitalized children (𝐼𝑏 and 𝐻𝑏) approach zero, while the vaccinated population (𝑉𝑏) reaches approximately 2.58 × 107, confirming the central role of vaccination in suppressing new infections. The concentration of environmental rotavirus particles (𝐶𝑟) also tends to zero, highlighting the combined efficacy of hygiene and sanitation interventions in reducing environmental transmission. Among the evaluated control strategies, the combination of vaccination, treatment, and hygiene (𝑆13) emerges as both the most cost-effective and epidemiologically impactful strategy. This approach achieves near-complete elimination of child infections at a moderate total cost of approximately $6.17×1011, yielding the best balance between health outcomes and economic feasibility. In contrast, the single-control strategies (𝑆1–𝑆5) achieve minimal infection reduction despite lower costs, while multi-control strategies involving all five interventions (𝑆17) provide marginal epidemiological improvement at substantially higher cost. The cost-effectiveness analysis, expressed as cost per health unit reduced, identifies vaccination (𝑢1) and treatment (𝑢3) as the primary contributors to financial cost, while hygiene adherence (𝑢5), sanitation (𝑢4), and education (𝑢2) offer strong epidemiological benefits with minimal marginal cost. This demonstrates that optimal disease control is achieved when vaccination and treatment are combined with sustained hygiene practices rather than through expensive full scale interventions. Overall, the results confirm that targeted multi control strategies particularly 𝑆13p rovide the most practical and sustainable pathway for reducing rotavirus transmission, minimizing infections, and optimizing public health expenditure.Item Thermodynamic Irreversibility of Steady Viscous Couette Flow With Convective Cooling and Temperature‐Dependent Viscosity(Wiley Periodicals, 2025-07-17) Kigodi, Odeli J.; Masasila, Nyanga H.The study on Thermodynamic Irreversibility of Steady Viscous Couette Flow with Convective Cooling and Temperature‐Dependent Viscosity reveals that increasing the pressure gradient parameter enhances both temperature and velocity profiles while reducing entropy production, indicating improved thermodynamic efficiency. Similarly, higher Reynolds numbers steepen the thermal and momentum boundary layers with complex patterns in entropy production caused by competing viscous and thermal effects, while increasing viscosity dampens velocity but retains more thermal energy, thereby reducing irreversibility’s. Rising Eckert numbers further amplify temperature yet lower entropy production due to viscous dissipation dominance, and higher Prandtl numbers improve heat transfer while reducing entropy production. Conversely, higher Brinkman numbers increase entropy production through intensified viscous dissipation, shifting the irreversibility contribution toward fluid friction, while elevated Biot numbers enhance convective heat transfer but raise entropy production near the boundary. The results show that key parameters markedly influence the coefficient of skin friction (Cf ) and coefficient of thermal convection (Nu), which regulate thermodynamic reversibility. While β1 and Bi decrease Nu with little effect on Cf , higher Ec and Re enhance Nu but reduce Cf , highlighting the coupled roles of frictional and thermal reversibility in entropy production. The novelty of this study lies in incorporating temperature‐dependent viscosity with convective cooling in the analysis of entropy production inviscous Couette flow, offering new insights into how simultaneous variations in key flow and thermal parameters govern the balance between frictional and thermal irreversibility’s. Overall, the results demonstrate that careful parameter tuning can significantly improve thermal performance and reduce irreversibility in Couette flow systems.Item Fixed point theorems for interpolative orthogonal relational in TVS-valued cone metric spaces(Mbeya University of Science and Technology, Mbeya, 2025) Wangwe, LucasThis article explores the fixed point theorem for a novel class of interpolative relation theoretical convex mappings in TVS-valued cone metric spaces, integrating relational theory, convexity, and interpolation properties to offer fresh perspectives and possible uses in theoretical and applied mathematics. An application of the results to differential equations and matrix equations in the context of orthogonal TVS-valued cone metric spaces is presented, along with a constructive example to support the findings.Item Energy resources: Their causal relationship with ecology and environments(Asia Pacific, 2025-01-15) Lyanda, Romanus Peter; Ojija, FredrickEnergy resources are critical drivers of economic development and societal progress, but their extraction, conversion, and use have profoundly impacted ecological systems and the environment. Therefore, it is essential to explore the relationships between energy resources and the environment throughout history. This paper examines the causal relationships between energy resource utilization and environmental changes, addressing both renewable and non-renewable energy sources. We analyze the environmental consequences of energy extraction and consumption, including pollution, habitat destruction, and climate change, and evaluate sustainable approaches to mitigate these effects. Fossil fuels have been the primary source of energy and are major contributors to greenhouse gas emissions, air and water pollution, and habitat destruction, all of which exacerbate global climate change. On the other hand, renewable energy sources such as wind, solar, and hydroelectric power are considered more sustainable. However, they also have environmental impacts, such as habitat disruption and high resource consumption. Researchers argue that trade-offs must be managed between increasing energy use, facilitated by technological advancements, and achieving sustainability. Energy generation and ecological goals should not be viewed as opposing or irreconcilable. With the implementation of appropriate policies, measures, and guidelines, energy production can be aligned with efforts to mitigate climate change and promote sustainability.Item Modelling campylobacteriosis dynamics: Impacts of contaminated animal products and environmental decontamination interventions(Scientific African, 2025-09-01) Trazias a ,Herman; Lusekelo,Eva; Abas, Kasim SakranCampylobacteriosis is responsible for approximately 500 million cases of illness globally each year. Globally, human campylobacteriosis infections and contaminated animal products cause an estimated loss of 8.6 and 12.6 billion US dollars annually, respectively. The disease is transmitted through consumption of contaminated foods and water, licking unsanitary hands and contact with infected hosts. As global demand for animal products like meat and milk continues to grow, the transmission of campylobacteriosis through these products has become a critical concern. This study aims at utilising mathematical modelling and analysis techniques to quantify the effects of contaminated animal products and environmental decontamination interventions on campylobacteriosis dynamics in host populations. A mathematical model as a system of ordinary differential equations is proposed with human and cattle populations and contaminated animal products. The next-generation matrix method is applied to compute the effective reproduction number that describes disease persistence and extinction. The global stability of equilibria states is examined using the Lyapunov stability theory. The uncertainty and sensitivity of model parameters are examined using the Latin Hypercube Sampling and Partial Rank Correlation Coefficient methods. Model fitting and parameter estimations are performed using the least squares method alongside the human cases from January to August for the years 2017 to 2020 in the EU. The analysis indicates that the disease-free and endemic equilibria are globally asymptotically stable whenever and , respectively. The numerical results show that the ingestion rates of contaminated animal products, shedding rates and the natural replication rates of Campylobacter jejuni bacteria are directly proportional to , while the environmental cleanliness and the decay rate of Campylobacter jejuni bacteria are inversely proportional to . In order to reduce the impact of contaminated animal products, the study recommends a couple of strategies for reducing shedding rates, killing bacteria, and vaccinating infected hosts.Item International Journal of Mathematical Sciences and Optimization: Theory and Applications 11(3), 2025, Pages 88 - 107 https://doi.org/10.5281/zenodo.17604615 Quantifying the Public Health Effects of Vaccine Hesitancy and Delays in Screening Clinically Infected Patients: Insights From a COVID-19 Transmission Model.(International Journal of Mathematical Sciences and Optimization: Theory and Applications, 2025-10-11) Lolika, Paride O.; Helikumi ,Mlyashimbi Kenneth Sube 3, Steady Mushayabasa 4; Sube , Kenneth; Mushayabasa,SteadyMotivated by the recent COVID-19 outbreak, we develop a time delay infectious disease model that incorporates vaccination and screening of clinically infected patients and calibrate it using Chinese data to understand the quantitative implications of vaccine hesitancy and delay in the screening of clinically infected patients. Vaccine hesitancy refers to the denial or delay in acceptance of vaccines despite their availability. Understanding the implications of vaccine hesitancy is therefore essential for designing public health interventions. Analysis of the model revealed that whenever R0 ≤ 1, there exists a globally asymptotically disease-free equilibrium. However, whenever R0 > 1, there exists a unique endemic equilibrium which is globally asymptotically stable. In addition, results also show that vaccine hesitancy and delay in hospitalizing clinically infected patients have a stronger impact on the deaths toll and new infections generated [1,2]. Vaccine hesitancy and delayed screening of clinically infected patients lead to harmonic oscillations in deaths and new cases, which, however, die out over time. Our findings underscore the importance of including vaccine hesitancy and delay in hospitalizing clinically infected patients in the design of control strategies for infectious diseases.Item Insights into the Optoelectronic and Thermoelectric Properties of Lead-Free Rb2NaIrF6 Double Perovskite Compound: A First-Principles Study.(Elsevier B.V, 2025-07-01) Mbiloa,Mwende; Musembib,Robinson; Kachirab,John Peter; Onsatea,Wisley Nyangau; Kehezea, Fanuel Mugwanga; Mapasha, Refilwe EdwinThis study investigated the structural, electronic, elastic, mechanical, thermodynamic, optical, and thermoelectric properties of the Rb2NaIrF6 lead-free double perovskite compound using first-principles methods. The structural stability of the perovskite was confirmed by the Goldschmidt tolerance and octahedral factors. Dynamic stability was confirmed through the negative energy of formation and positive frequency modes of the phonon dispersion curve. The dynamic stability results suggest that the studied compound could be potentially synthesised experimentally. The Rb2NaIrF6 compound is a direct semiconductor with electronic band gaps within the range of 2.14-3.76 eV, computed using different approximations. The mechanical stability was confirmed by the elastic calculation results. The Rb2NaIrF6 compound was found to be ductile, ionic, and anisotropic. The optical properties showed that Rb2NaIrF6 strongly absorbs light in the ultraviolet region, which is desirable for ultraviolet-photosensitive materials in optoelectronic devices. The computed thermoelectric figure of merit of the Rb2NaIrF6 compound is 0.81 at 1000 K, suggesting high thermoelectric efficiency. These findings demonstrate the potential of Rb2NaIrF6 lead-free double perovskite compound for optoelectronic and thermoelectric applications. Therefore, our investigation offers theoretical insights that can lead to the experimental synthesis and study of Rb2NaIrF6 lead-free double perovskites.Item Modeling the implications of seasonality and heterogeneous mean worm burden in Guinea-worm disease dynamics in dog population.(Nonlinear Science, 2025-05-09) Lusekelo ,Eva; Daudi ,Salamida; Helikumi , Mlyashimbi; Mushayabasa, SteadyPrior to 2012, it was believed that only humans could host Guinea-worm disease. Recent findings show that dogs also act as hosts. With the 2030 goal for eradicating Guinea-worm approaching, understanding dogs’ roles is crucial. We develop a mathematical model to study seasonal Guinea-worm disease, focusing on dogs as primary hosts, given the low human cases. Our model includes seasonal variations, as previous studies indicate that disease prevalence is linked to seasonal fisheries. We also categorize infectious dogs based on their average worm burden. Our analysis examines how dog screening and tethering influence disease dynamics. Results indicate that both strategies can lower disease transmission. However, they may not be enough for total eradication on their own. Therefore, we suggest combining these methods with additional actions, like dog culling, to improve disease control.Item Thermal and Entropic Analysis of Viscous Fluid Flow in a Porous Channel With Convective Heat Transfer and Magnetic Field Aspects(Wiley, 2025-12-27) Kigodi Odeli J.; Masasila Nyanga H.; Faisa Muhammad; Badruddin Irfan Anjum.; Abdel Ahmed Said.; Zedan Hafez.; Chacha Chacha,SThis study examines the thermal and entropy generation characteristics of viscous fluid flow through a porous channel under convective cooling and magnetic field effects. The flow is modeled using the steady state momentum and energy equations and solved numerically via a finite difference scheme. Parametric variations in Darcy number ( Da), magnetic parameter ( M ), pressure gradient ( A ), Biot number ( Bi ), Prandtl number ( Pr), Eckert number ( Ec), and internal heat generation ( Q ) are analyzed. Results show that increasing M from 0 to 20 reduces entropy generation by approximately 18%, while raising Bi from 0 to 0.6 decreases entropy by about 12%. Higher Da and Q promote thermal buildup but increase irreversibility, whereas stronger M and Bi stabilize flow, lower temperatures, and improve thermodynamic efficiency. The Nusselt number increases with Bi and Ec, enhancing heat transfer, while skin friction decreases with stronger magnetic fields. These findings provide practical guidance for selecting permeability, magnetic field strength, and surface heat transfer characteristics to optimize energy efficiency and thermal performance in porous channel thermal systems and magnetohydrodynamic applications.Item Concerning the Status of Mathematics and Physics for Secondary School Science Students’ Sustainability in hhe 21st Century STEM Disciplines(Isack E. Kibona, 2026-01-08) Kibona,Isack E.The National Examination Council of Tanzania plays a significant role in shaping secondary school graduates’ career pathways through the Certificate of Secondary School Education (CSEE). This study examined future implications and strategies for improving graduates’ prospects in Science, Technology, Engineering, and Mathematics (STEM) fields, using the 2022 CSEE results from secondary schools in Mbeya CityItem Understanding the Complex Aroma Profile of Durian Fruit: A Concise Review(Journal of Food Science, 2025-02-12) Sospeter, Eliwanzita; Ding, Phebe; Fang, Teh Huey; Misran, Azizah; Abas, Faridah; Dey, GargiDurian fruit (Durio sp.) is a tropical fruit native to Southeast Asian countries known for its strong and unique characteristic smell. This review provides comprehensive information on durian fruit aroma, which is characterized by various volatile compounds, with esters and sulfur compounds playing a key role. Additionally, the contribution of ketones, alcohols and aldehydes to its unique aroma cannot be overlooked. The important precursors for the generation of these volatiles are branched-chain amino acids and polyunsaturated fatty acids. Moreover, the abundance and composition of aroma volatiles in durian fruit can be affected by various influencing factors, including genetic background, post-harvest handling, and processing. This review also provides the common methods used to extract and analyze durian aroma components, with solid-phase microextraction gas chromatography-mass spectrometry emerging as a suitable and precise method to extract and analyze the complex aroma chemistry of the durian fruitItem Modeling the Effects of Human Awareness and Use of Insecticides on the Spread of Human African Trypanosomiasis: A Fractional-Order Model Approach(Licensee MDPI, Basel, Switzerland., 2025-09-22) Koga, Oscar; Helikumi, Mlyashimbi; Mayengo, Maranya; Mhlanga,AdquateIn this research work, we proposed and studied a fractional-order model for Human African Trypanosomiasis (HAT) disease transmission, incorporating three control strategies: health education campaigns, prevention measures, and use of insecticides. The theoretical analysis of the model was presented, including the computation of disease-free equilibrium and basic reproduction number. We performed the stability analysis of the model and the results showed that the disease-free equilibrium point was locally asymptotically stable whenever R0 < 1 and unstable when R0 > 1. Furthermore, we performed parameter estimation of the model using HAT-reported cases in Tanzania. The results showed that fractional-order model had a better fit to the real data compared to the classical integerorder model. Sensitivity analysis of the basic reproduction number was performed using computed partial rank correlation coefficients to assess the effects of parameters on HAT transmission. Additionally, we performed numerical simulations of the model to assess the impact of memory effects on the spread of HAT. Overall, we observed that the order of derivatives significantly influences the dynamics of HAT transmission in the population. Moreover, we simulated the model to assess the effectiveness of proposed control strategies. We observed that the use of insecticides and prevention measures have the potential to significantly reduce the spread of HAT within the population.Item Insect-pollinators and their interactions with plants differ in disturbed and semi-natural areas: Tanzania’s Southern Highlands case study.(SCIENCE PROGRESS, 2023) Ojija, Fredrick; S Adam, Lusekelo; Nicholaus , ReganDue to inadequate insect-pollinator data, particularly in sub-Saharan African countries like Tanzania, it is difficult to manage and protect these species in disturbed and semi-natural areas. Field surveys were conducted to assess insect-pollinator abundance and diversity and their interactions with plants in disturbed and semi-natural areas in Tanzania’s Southern Highlands using pan traps, sweep netting, transect counts, and timed observations techniques. We found that species diversity and richness of insect-pollinators were high in semi-natural areas, and there was 14.29% more abundance than in disturbed areas. The highest plant-pollinator interactions were recorded in semi-natural areas. In these areas, the total number of visits by Hymenoptera was more than three times that of Coleoptera, while that of Lepidoptera and Diptera was more than 237 and 12 times, respectively. Hymenoptera pollinators had twice the total number of visits of Lepidoptera, and threefold of Coleoptera, and five times more visits than Diptera in disturbed habitats. Although disturbed areas had fewer insect-pollinators and fewer plant–insect–pollinator interactions, our findings indicate that both disturbed and semi-natural areas are potential habitats for insect-pollinators. The study revealed that the over-dominant species Apis mellifera could influence diversity indices and network-level metrics in the study areas. When A. mellifera was excluded from the analysis, the number of interactions differed significantly between insect ordersItem Halotolerant Pseudomonas koreensis S4T10 mitigate salt and drought stress in Arabidopsis thaliana(Physiologia Plantarum, 2023-11) Nathanael Kalleku, Justine; Ihsan, Samsoor; Ibrahim Al-Azzawi, Tiba NazarSalt and drought are documented among the most detrimental and persistent abiotic stresses for crop production. Here, we investigated the impact of Pseudomonas koreensis strain S4T10 on plant performance under salt and drought stress. Arabidopsis thaliana Col-0 wild type and atnced3 mutant plants were inoculated with P. koreensis or tap water and exposed to NaCl (100 mM) for five days and drought stress by withholding water for seven days. P. koreensis significantly enhanced plant biomass and photosynthetic pigments under salt and drought stress conditions. Moreover, P. koreensis activated the antioxidant defence by modulating glutathione (GSH), superoxide dismutase (SOD), peroxidase (POD), and polyphenol oxidase (PPO) activities to scavenge the reactive oxygen species produced due to the stress. In addition, the application of P. koreensis upregulated the expression of genes associated with antioxidant responses, such as AtCAT1, AtCAT3, and AtSOD. Similarly, genes linked to salt stress, such as AtSOS1, AtSOS2, AtSOS3, AtNHX1, and AtHKT1, were also upregulated, affirming the positive role of P. koreensis S4T10 in streamlining the cellular influx and efflux transport systems during salt stress. Likewise, the PGPB inoculation was observed to regulate the expression of drought-responsive genes AtDREB2A, AtDREB2B, and ABA-responsive genes AtAO3, AtABA3 indicating that S4T10 enhanced drought tolerance via modulation of the ABA pathway. The results of this study affirm that P. koreensis S4T10 could be further developed as a biofertilizer to mitigate salt and drought stress at the same time.Item Assessment of Heavy Metals in Wild and Farmed Tilapia (Oreochromis Niloticus) on Lake Kariba, Zambia: Implications for Human and Fish Health(Taylor & Francis, 2022) Simukoko, Chalumba K.; Mwakalapa, Eliezer B.; Bwalya, Patricia; Muzandu, Kaampwe; Berg, Vidar; Mutoloki, Stephen; Polder, Anuschka; Lyche, Jan, L.The aim of this study was to assess the levels of heavy metals in both wild and farmed tilapia on Lake Kariba in Zambia and to evaluate the impact of intensive fish farming on wild tilapia. Three sites for wild fish (2 distant and 1 proximal to fish farms) and two fish farms were selected. One hundred fish (52 from distant sites; 20 near fish farms; 28 farmed fish) were sampled and muscle tissues excised for analysis of heavy metals (Mg, Fe, Zn, Al, Cu, Se, Co, Mo, As, Cr, V, Ni, Hg, Pb, Li, Cd, and Ag) by acid (HNO3) digestion and ICP-MS. All metals were found to be below the maximum limits (MLs) set by WHO/EU. Essential metals were higher in farmed tilapia, whereas non-essential metals were higher in wild tilapia. Significantly higher levels of essential metals were found in wild fish near the fish farms than those distant from the farms. Estimated weekly intake (EWI) for all metals were less than the provisional tolerable weekly intakes (PTWI). Target hazard quotients (THQ) and Hazard Indices (HI) were <1, indicating no health risks from a lifetime of fish consump- tion. Selenium Health Benefit Value (HBVSe) was positive for all locations, indicating protective effects of selenium against mercury in fish. Total cancer risk (CR) due to As, Cr, Cd, Ni and Pb was less than 1 × 10−4, indicating less than 1 in 10,000 carcinogenic risk from a lifetime consumption of tilapia from Lake Kariba. Hg levels (0.021 mg/kg) in wild tilapia at site 1 were higher than the Environmental quality standard (EQS = 0.020 mg/kg) set by EU, indicating possible risk of adverse effects to fish. Except for Hg, levels of metals in fish were safe for human consumption and had no adverse effects on fish.Item Concerning the status of mathematics and physics for secondary school science students’ sustainability in the 21st century STEM disciplines(ORIGINAL RESEARCH ARTICLE, 2026-01-08) Kibona ,Isack EThe National Examination Council of Tanzania plays a significant role in shaping secondary school graduates’ career pathways through the Certificate of Secondary School Education (CSEE). This study examined future implications and strategies for improving graduates’ prospects in Science, Technology, Engineering, and Mathematics (STEM) fields, using the 2022 CSEE results from secondary schools in Mbeya City.