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Kinetics and energetics of biodiesel oxidation stability: The impact of Uapaca kirkiana-derived natural antioxidants
No full textThis research article was published by Biofuels, Bioproducts and Biorefining Volume19, 2025Despite considerable progress in understanding biodiesel autoxidation inhibition, the kinetics and energetics of the inhibition reactions involving natural antioxidants remain underexplored. Most existing research on natural antioxidants has focused on enhancing oxidation stability and other fuel properties. This study aimed to investigate the oxidative stability of croton biodiesel (CBD) and assess the kinetics and energetics of natural antioxidants derived from the roots, pulp, and fruit peels of the Uapaca kirkiana plant. The oxidation stability of biodiesel samples was assessed using the OXITEST method at temperatures of 90, 100, 110, and 120 °C. These tests enabled the calculation of kinetic parameters such as reaction rates and activation energies, crucial for understanding the inhibition role of antioxidants during oxidative degradation. Activation energy for antioxidant consumption, determined using the Arrhenius equation, was found to be 81.39 kJ mol−1 for fruit peel extracts, 77.73 kJ mol−1 for pulp extracts, and 63.85 kJ mol−1 for root bark extracts. The higher activation energy for fruit peel extracts suggests that they are more effective at preventing oxidation, especially under high-temperature conditions. Enthalpy, entropy, and Gibbs free energy parameters were calculated using the Eyring equation, indicating a nonspontaneous endothermic process for the antioxidant samples. The study found an inverse relationship between antioxidant concentration and rate constants, demonstrating the antioxidants' effectiveness in slowing down the oxidation process. These kinetics and energetics analyses provide detailed insights into how antioxidants function, facilitating the optimization, selection, and validation of their efficiency in stabilizing biodiesel
Electro-spun transparent film from banana pseudo-stem native cellulose using N-methylmorpholine-N-oxide solvent system
No full textThis research article was published by Materials Today Communications, 2025The study-utilized electrospinning to prepare a transparent film from native cellulose extracted from banana pseudo stems. The process of electrospinning was performed at room temperature conditions, after which the cellulose film was obtained through water coagulation. Dimethyl sulfoxide and dimethylformamide were added to the electrospinning solution to adjust the surface tension, viscosity, and conductivity of the prepared solutions. The formed thin film was characterized using Infrared spectroscopy (IR) and X-ray crystallography tests to confirm the elimination of non-cellulosic materials during extraction. It was revealed that the banana fibers were dominated by crystallinity and converted from cellulose-I to cellulose-II after dissolution in N-methyl morpholine N-oxide (NMMO). Scanning electron microscopy images revealed that fiber and electro-spun film morphologies could be achieved by varying sodium hydroxide solution concentration and solution parameters during fiber treatment and electrospinning. Concentration of 17.5 % (wt./v)of the alkaline solution showed to be more effective in changing the surface morphology of the fiber. The structure and mechanical characteristics of the films were influenced most by the concentration of banana native cellulose, process stability, and the solidification of the electro-spun fibers. The film exhibited an initial degradation temperature of 165°C, a light transmittance of 83.3 % in the visible UV range, and a tensile strength ranged from 5.83 MPa to 8.13 MPa. This performance highlights its potential applications in various fields, including packaging and biomedical engineering
Field vaccination of locally-owned cattle against malignant catarrhal fever under environmentally challenging conditions in Tanzania
No full textThis research article was published by Vaccine Volume 45, 25 January 2025Malignant catarrhal fever (MCF), caused by alcelaphine herpesvirus-1 (AIHV-1) transmitted from wildebeest, is a lethal cattle disease with significant impacts on East African pastoralists. Development of a live attenuated MCF vaccine has prompted research into its use in communities at risk. This study reports results from the first utilisation of the MCF vaccine in locally-owned cattle under field conditions. The study involved a primary two-dose course vaccination of 1634 cattle, followed a year later, by boost vaccination of 385 of these cattle. It aimed to: (a) evaluate the antibody response to a two-dose AlHV-1 primary vaccination course, including initial response, antibody levels after one year, and clinical events post-vaccination; (b) assess how factors like age, reproductive status, body condition, and breed influence the initial response; and (c) compare antibody responses to single- and two-dose booster protocols one year after primary vaccination. Analyses were carried out using linear mixed-effects models and paired t-tests.
Clinical incidents were reported in 11/1634 cattle vaccinated during the primary course and in 0/385 cattle during the boost regimens. The primary vaccination resulted in a 9-fold increase in comparison to pre-vaccination antibody levels and the response was consistent across animals of different ages, reproductive statuses and body conditions. While antibody levels declined 11 months after primary vaccination, they remained high, and a single-dose booster vaccination was sufficient to elicit a strong immune response, with only marginal increases after a second booster.
The study provides evidence of high immunogenicity and low incidences of clinical events of the vaccine in cattle across individual host factors and immunologically vulnerable groups, under prevailing environmental conditions. It also indicates the utility of a single-dose booster regimen. These findings will support progress towards commercial production and larger-scale adoption which could generate important benefits for the livelihoods, and sustainability of pastoral livestock systems
Application of Nanotechnology in Enhancing Efficacy of African Herbal Medicines-A review
Full text linkThis research article was published by Preprints ,2025African herbal medicine has been used for centuries as a means of treating various ailments.
However, limitations in the effectiveness and delivery of these herbal remedies have necessitated
exploration of alternative approaches to enhance their efficacy. Nanotechnology offers promising
solutions by providing novel methods for delivery, targeting, and controlled release of bioactive
compounds from the herbal medicines. This paper reviews application of nanotechnology in
improving the efficacy of African herbal medicine. The use of nanocarriers, such as liposomes, solid
lipid nanoparticles, polymeric nanoparticles, and nano emulsions, to encapsulate and deliver
bioactive compounds have been discussed. Additionally, various nanotechnology-based strategies,
including surface modification, targeted drug delivery, and stimuli-responsive systems have also
been explored. Finally, the review has explored future perspective of African herbal medicine by
looking at their safety considerations, regulatory aspects, and commercialization potential. The
integration of nanotechnology applications with African herbal medicine has the potential to
revolutionize traditional healthcare practices in Africa, by providing cheaper and effective
therapeutic options to conventional medicine
Predicting customer subscription in bank telemarketing campaigns using ensemble learning models
Full text linkThis research article was published by Machine Learning with Applications Volume 19, 2025This study investigates the use of ensemble learning models bagging, boosting, and stacking to enhance the accuracy and reliability of predicting customer subscriptions in bank telemarketing campaigns. Recognizing the challenges posed by class imbalance and complex customer behaviors, we employ multiple ensemble techniques to build a robust predictive framework. Our analysis demonstrates that stacking models achieve the best overall performance, with an accuracy of 91.88% and an Receiver Operating Characteristic Area Under the Curve (ROC-AUC) score of 0.9491, indicating a strong capability to differentiate between subscribers and non-subscribers. Additionally, feature importance analysis reveals that contact duration, economic indicators like the Euro interbank offered (Euribor) rate, and customer age are the most influential factors in predicting subscription likelihood. These findings suggest that by focusing on customer engagement and economic trends, banks can improve telemarketing campaign effectiveness. We recommend the integration of advanced balancing techniques and real-time prediction systems to further enhance model performance and adaptability. Future work could explore deep learning models and interpretability techniques to gain deeper insights into customer behavior patterns. Overall, this study highlights the potential of ensemble models in predictive modeling for telemarketing, providing a data-driven foundation for more targeted and efficient customer acquisition strategies
Development of ternary PANI/GO-Fe3O4@AgNps nanocomposites for photocatalytic remediation of toxic dye effluent under energy-efficient system
Full text linkThis research article was published by Journal of Molecular Structure /Volume 1324/ 2025The environmental toxicity of effluents contaminated with synthetic industrial dyes and their resistance to conventional treatments drive the need for developing innovative treatment technologies such as visible photoactive catalysts in a photocatalytic system. In this study, novel nanocomposite photocatalysts were synthesized for photocatalytic remediation of toxic dye effluent under energy-efficient Light Emitting Diode (LED) irradiation. Concise instrumental analysis was used to investigate the morphological, functional, particle size, thermal and optoelectronic features of the developed photocatalytic nanocomposites. Their performance was tested with cationic (methylene blue) and anionic (methyl orange) model dyes. The instrumental elucidation reveals the coating of amorphous polyaniline with other composites, giving the blend rapid reactivity, which promotes photocatalyst-dye interaction. The composites exhibit lowered bandgap (2.66 eV, 2.85 eV and 2.27 eV) when compared to polyaniline (3.34 eV) used as macromolecular support via in situ coupling. This accounts for the efficiency of 95 % and 98 % reported for methylene blue and methylene orange, respectively, at optimal experimental conditions of 90 min irradiation time, pH of 5 and dosage of 20 mg/100 mL dye effluent. The study also proposed a Z-scheme mechanism with the vital role of •O2 –, •OH and h+ reactive species in the photodegradation of the dye molecules
Techno‐Economic Evaluation of Synthetic and Natural Antioxidants Used for Enhancing Oxidation Stability of Biodiesel
No full textThis research article was published by Energy Science & Engineering, 2025The oxidation stability of biodiesel is a critical factor affecting its storage and performance, necessitating the use of antioxidants to enhance its shelf life and reliability. Both natural and synthetic antioxidants have proven effective in improving the oxidation stability of biodiesel, with numerous studies demonstrating their ability to extend the induction period and delay oxidative degradation. However, while the technical efficacy of these antioxidants is well‐documented, the techno‐economic analysis that evaluates the cost‐effectiveness of using natural versus synthetic antioxidants remains unexplored. This creates uncertainty in selecting the most sustainable and economically viable antioxidant option. This study aimed to conduct a techno‐economic analysis comparing the cost‐effectiveness of synthetic and natural antioxidants in stabilizing biodiesel. The study evaluated synthetic antioxidants, specifically hydrogenated methoxy eugenol, and natural antioxidants derived from the methanolic extract of wild loquat plants, along with a comparison to commonly used synthetic antioxidants. Comprehensive simulations and modeling were conducted using Aspen Plus® V10 commercial simulation software in a block‐wise manner. The technical performance was assessed by considering the quantities and qualities of biodiesel, glycerol, and antioxidants. The synthetic antioxidant processes resulted in negative net present values and longer payback periods of 11.7 to 17.8 years, while natural antioxidants showed shorter payback periods ranging from 3.8 to 12 years. Natural antioxidants, particularly those extracted from clove wastes and wild loquat plant parts, demonstrated superior techno‐economic performance with the lowest operating and raw materials costs, shortest payback period, highest internal rate of return (IRR), and best profitability. Therefore, natural antioxidants are the most economically viable option for biodiesel stabilization, outperforming synthetic antioxidants in terms of operating costs, payback period, IRR, and profitability
Towards Efficient Video Codec for 360-degree Video Streaming over Broadband Network
No full textThis research article was published in the Indian Journal of Science and Technology, Volume: 18, Issue: 5, 2025Objectives: This study presents the compression efficiency analysis of AV1, H.265/HEVC, and VVenc based on the Peak Signal-to-Noise Ratio (PSNR) and Video Multimethod Assessment Fusion (VMAF) objective quality metrics. Methods: The study utilizes video sets from publicly available databases and YouTube. The video sets were compressed using High Efficient Video Codec (HEVC/H.265) and Versatile Video Encoder (VVenc) based on Common Test Conditions (CTC) for fixed-quality encoding at different rates. For STV-AV1, we use quantization parameters which result in the rate nearly the same as that of CTC. The encoders’ performance was evaluated using PSNR and VMAF objective metrics. Rate-distortion curves were constructed, and Bjøntegaard delta metric was computed to obtain bitrate saving/overhead between encoders. Findings: The superiority of the Versatile Video Encoder (VVenc) over STV-AV1 was unchallenged in eight out of twelve encoded 360-degree videos. The maximum bitrate saving of 72.6% and minimum of 12.8% is attained by the VVenc encoder compared to SVT-AV1. For the case of the HEVC encoder, the maximum and minimum bitrate overhead of 89.5% and 19.2% is required for it to achieve video quality similar to that of VVenc encoded video. Based on bit-rate saving, the SVT-AV1 encoder is the second most performing, especially for 6K and 5K resolution videos. It is further observed that the HEVC encoder outperforms VVenc and SVT-AV1 only in two video scenes, with average bitrate savings of 34.1% and 1.3%, respectively. Even though the popularity of HEVC still exists in most encoded 360-degree videos, the open-source STV-AV1 showed better results by outshining the HEVC in eleven out of twelve 360-degree video sets. The VVenc, an open-source version of H.266 surpasses other encoders, however, up to this moment, most of the Virtual reality platforms do not support the H.266 format. Novelty: High-resolution 360-degree video requires high-speed network infrastructure to transmit video packets. Therefore, a bandwidth-efficient video encoder must be selected to ensure an adequate immersive experience. It is well known that the HEVC encoder performance is far better than its predecessor X.264 yet, most publicly available 360-degree databases and published research works are based on video sequences encoded by using X.264 and few utilize the HEVC encoder. However, based on findings, STV-AV1 outshines HEVC with average bitrate saving of 11.6%, 34.9%, and 58% in 8K, 6K, and 4K resolution respectively making it a suitable candidate for encoding high-resolution 360-degree videos
Effect of waste water bottle and treated sisal fibers on the durability and mechanical properties of concrete
No full textThis research article was published scientific reports Volume 15, 2025Globally, the disposal of waste plastic bottles is challenging. However, many researchers reported the importance of incorporating waste polyethylene-based waste water bottles (WWB) as a fiber and treated sisal fiber separately in the concrete mixture. However, it is novel to reinforce concrete by WWB fiber and treated sisal fiber together for more production of sustainable concrete. So the present study investigated the effect of using different doses of WWB fiber with and without treated sisal fiber on the physical and mechanical properties of concrete. Also, it is detail discussed its effect on concrete durability like in different elevated temperatures and acidic environments. As the result indicates, the reinforcement of concrete by WWB and treated sisal fibers lessens the fresh density and in 5% of HCl solution, it give higher strength and lower mass loss compared to the control concrete. Also, concrete WF25 increased compressive strength by 34.6%, 7.42%, and 3.6% respectively at 28, 56, and 180 days of concrete age, while concrete sample WF100 highly increased the splitting tensile strength of concrete by 26.67% compared to the control concrete mixture. Concrete having only WWB without treated sisal fiber reduced water absorption, increased mass loss, and lessened strength at 200, 300, and 400 °C elevated temperatures. So, this study is significant for implementing improved construction material performance by WWB and treated sisal fibers, as well as supporting the reduction of plastic bottles from the environment
Kinetics and energetics of biodiesel oxidation stability: The impact of Uapaca kirkiana-derived natural antioxidants
No full textThis research article was published by Biofuels, Bioproducts and Biorefining (Biofpr) Volume 19, 2025Despite considerable progress in understanding biodiesel autoxidation inhibition, the kinetics and energetics of the inhibition reactions involving natural antioxidants remain underexplored. Most existing research on natural antioxidants has focused on enhancing oxidation stability and other fuel properties. This study aimed to investigate the oxidative stability of croton biodiesel (CBD) and assess the kinetics and energetics of natural antioxidants derived from the roots, pulp, and fruit peels of the Uapaca kirkiana plant. The oxidation stability of biodiesel samples was assessed using the OXITEST method at temperatures of 90, 100, 110, and 120 °C. These tests enabled the calculation of kinetic parameters such as reaction rates and activation energies, crucial for understanding the inhibition role of antioxidants during oxidative degradation. Activation energy for antioxidant consumption, determined using the Arrhenius equation, was found to be 81.39 kJ mol−1 for fruit peel extracts, 77.73 kJ mol−1 for pulp extracts, and 63.85 kJ mol−1 for root bark extracts. The higher activation energy for fruit peel extracts suggests that they are more effective at preventing oxidation, especially under high-temperature conditions. Enthalpy, entropy, and Gibbs free energy parameters were calculated using the Eyring equation, indicating a nonspontaneous endothermic process for the antioxidant samples. The study found an inverse relationship between antioxidant concentration and rate constants, demonstrating the antioxidants' effectiveness in slowing down the oxidation process. These kinetics and energetics analyses provide detailed insights into how antioxidants function, facilitating the optimization, selection, and validation of their efficiency in stabilizing biodiesel