A novel tantalum pentoxide nanoparticle-electrochemically reduced graphene oxide nanocomposite-modified glassy carbon electrode (Ta₂O₅-ErGO/GCE) was developed for the detection of oxytetracycline in milk. The composition, structure and morphology of GO, Ta₂O₅, and Ta₂O₅-ErGO were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Oxytetracycline electrochemical behavior on the bare GCE, GO/GCE, ErGO/GCE, and Ta₂O₅-ErGO/GCE was studied by cyclic voltammetry. The voltammetric conditions (including scan rate, pH, deposition potential, and deposition time) were systematically optimized. With the spacious electrochemical active area, the Ta₂O₅-ErGO/GCE showed a great magnification of the oxidation signal of oxytetracycline, while that of the other electrodes (GCE, GO/GCE, ErGO/GCE) could not reach the same level. Under the optimum conditions, the currents were proportional to the oxytetracycline concentration in the range from 0.2 to 10 μM, and a low detection limit of 0.095 μM (S/N = 3) was detectable. Moreover, the proposed Ta₂O₅-ErGO/GCE performed practically with satisfactory results. The preparation of Ta₂O₅-ErGO/GCE in the current work provides a minor outlook of detecting trace oxytetracycline in milk.

Rift Valley Fever virus (RVFV) is a zoonotic arbovirus of public health impact infecting livestock, wildlife, and humans mainly in Africa and other parts of the world. Despite its public health imp...

Background: People living with HIV (PLHIV) with good adherence to antiretroviral therapy (ART) achieve good health outcomes. However, treatment interruptions remain a major challenge, particularly in rural Africa. This study explored factors related to dropout, return, retention in care, and treatment adherence among PLHIV returning to care after missing clinical visits. Methods: We conducted an exploratory study using a phenomenological approach in rural South-eastern Tanzania, from July to October 2023. In-depth interviews (IDIs) were conducted with 21 PLHIV who resumed care after missing visits for three months or more from the last scheduled appointment and who were taking ART less than 60 days within the last three months, and their 13 treatment supporters. Interviews were conducted at St. Francis Regional Referral Hospital and Kibaoni Health Center.Five focus group discussions (FGDs) were conducted with 6– 8 healthcare workers from Kibaoni, Mang’ula, Mkamba, Mgeta Health Center, and St. Francis Hospital. Data were analyzed by thematic analysis, with NVivo 12 software. Results: The median age of the 21 PLHIV was 40 years (range 21 to 63); 10 (47.6%) were females. Reasons for dropping out of care reported included fear of disclosure, complacency with improved health, denial of HIV status, work-related absence, and religious beliefs. Reasons for returning included health deterioration, completion of work obligations causing care interruption, family support, and clinic follow up. Factors promoting retention and adherence were improved health through ART, trust in healthcare services, counseling, health education, clinic follow-up, longer drug refill periods, and family support. Conclusion: Our study highlights persisting stigmatization contributing to dropping from care, with strong family and social support improving adherence and clinic attendance. Future interventions should focus on these factors to enhance retention of lifelong treatment adherence. Working obligations remain a challenge, that could be addressed by facilitated access to remote drug pickup.

The main aim of the present study was to formulate a convenient plant-based yoghurt (PBY) with essential nutrients and bioactive compounds comparable to that of cow's milk using locally available ingredients in East Africa. Linear programming (LP) was applied for ratios optimization. The fermentation technique was deployed using commercial yoghurt culture (Streptococcus thermophilus and Lactobacillus bulgaricus) to develop a palatable and functional yoghurt. Laboratory analysis was conducted to validate the nutritional and functional values calculated by LP, and their relative difference was also calculated. PBY was analyzed for lactic acid bacteria (LAB) viability and storage stability for the 1st, 7th, and 14th day of refrigeration storage (4°C). Results showed that LP-optimized PBY could be formulated at a low cost of USD 0.9/kg, which is 60% cheaper than Alpro natural PBY. The formulation contained 37.87% and 18.88% of total Monounsaturated Fatty acids (MUFAs) and total Polyunsaturated Fatty acids (PUFAs), respectively. PBY riches in essential nutrients and functional properties enough to meet the Recommended Daily Intake (RDI) for 2-10-year old children. Formulated PBY were microbiologically stable for 14 days of storage and were found within acceptable standards specified by the Food Standard Australia New Zealand (FSANZ) and the East African Standard for yoghurt (EAS 33:2006). Plant-based yoghurt rich in nutrient bioavailability and bioactive compounds can be formulated using locally available ingredients and considered as an alternative to yoghurt.