Moi University

The perovskite solar cell (PSC) as an emerging and promising type of solar cell has been extensively studied, but instability is still a major challenge. Replacing the hygroscopic organic hole transport layer (HTL) in PSCs can result in an improvement in the device stability. However, it is still difficult to deposit inorganic HTLs onto the underlying perovskite layer without eroding or distorting it in the regular n-i-p architecture, thereby inducing defects at the interface and reducing the performance of the device. In this study, the performance of PSCs with an inorganic HTL is modelled using SCAPS-1D. The perovskite-HTL interface defect density was varied from 1.0 & times; 1012 to 1.0 & times; 1020 cm-3. We realized that, for PSCs based on some hole transport materials (HTMs), the effect of interface defect density was not significant. We observed that the HTL/perovskite valence band offset (VBO) plays a significant role in the phenomenon observed. In particular, a zero or slightly positive VBO results in an increase in both the defect tolerance and device efficiency. This information provides insights into the fabrication of PSCs with improved interface defect passivation and also enables the fabrication of perovskite solar cells based on physically deposited inorganic charge transport materials.

The clinical severity of COVID-19 is influenced by cellular and humoral immune responses, as well as the dynamics of viral replication. In line with this, the current study examined systemic and mucosal immunity responses alongside viral load in unvaccinated SARS-CoV-2-infected individuals during the period of Omicron predominance. Between 2022 and 2023, when Omicron prevalence was at its peak, 48 SARS-CoV-2-positive cases with varied severity were recruited using positive PCR testing, and 48 negative controls were recruited using negative PCR testing at Moi Teaching and Referral Hospital, Kenya. Severe patients showed higher viral loads and systemic anti-spike IgG levels compared to moderate and asymptomatic individuals. Asymptomatic individuals had higher mucosal anti-spike IgG and receptor-binding domain (RBD) levels compared to severe patients. Systemic IFN-alpha mRNA transcripts were higher in asymptomatic individuals compared to patients with severe COVID-19 and healthy individuals. Severe patients had significantly lower expression of IFN-gamma mRNA transcript levels in both blood and mucosa, as well as significantly lower systemic IFI-16 mRNA transcript levels. These findings reflect associations observed in a cross-sectional design and should not be interpreted as causal mechanisms. Suppressed interferon responses, both mucosal and systemic, were associated with severe disease. In conclusion, high systemic IgG and viral loads and low interferon responses were closely linked to severe COVID-19 outcomes.

BackgroundAgriculture remains central to Ghana’s economy, contributing nearly 20% of GDP and employing one-third of the labor force. Yet the sector faces persistent challenges, including low productivity, postharvest losses, limited mechanization, and inadequate value addition. In response, the Government of Ghana launched flagship initiatives, 1D1F and PFJ, to stimulate agro-industrialization, create employment, and promote inclusive growth. This study evaluates the effectiveness of these policies in promoting economic development.MethodsA quantitative research design was applied, drawing on secondary data from the Central Bank of Ghana covering 2003–2023. Ordinary Least Squares (OLS) regression and Poisson Pseudo-Maximum-Likelihood (PPML) estimators were used to examine the relationship between agricultural industrialization, innovation, and GDP growth. Document analysis of government reports and policy papers complemented the statistical findings.ResultsThe findings of this paper reveal that government policies (dummy for 2017) were effective in promoting economic growth through agro-Industrialization. Ghana’s initiatives—such as PFJ and 1D1F have played a vital role in advancing agro-industrialization, stimulating economic expansion, reducing poverty, and driving structural transformation. These interventions have functioned as catalytic platforms, spurring technological progress, value enhancement, and employment creation.RecommendationsPolicymakers should make deliberate efforts to align the pursuit of foreign exchange earnings with the objective of national food security. Prioritize deeper Value Chain Linkages. Progress beyond merely constructing factories and instead institutionalizing stronger connections between PFJ producers and 1D1F processors, accomplished through contract farming arrangements and improved market information systems. Ongoing contributions from both government and private actors in rural transportation, energy distribution, and storage facilities are essential. Such investments would curtail post-harvest losses, reduce transaction expenses, and enhance the overall competitiveness of the agro-industrial sector.

Fragmented tropical forests urgently need practical, cost-effective tools to assess ecosystem health and direct management resources where they matter most. Butterflies of the genus Charaxes are promising candidates: their larvae depend on specific woody host plants, and adults are readily sampled using fruit-baited traps, linking assemblage patterns directly to forest structure and quality. We assessed Charaxes diversity, disturbance responses and habitat associations across North Nandi Forest (similar to 11,000 ha; 1700-2130 m a.s.l.) and South Nandi Forest (similar to 15,000 ha; 1600-2000 m a.s.l.), two of Kenya's last Guineo-Congolian rainforest fragments. Six sites spanning a disturbance gradient were sampled monthly throughout 2023, with Van Someren-Rydon fruit-baited traps and visual censuses deployed concurrently at all sites to ensure comparability. A total of 1847 individual Charaxes belonging to 18 species were recorded. Both forests maintained high diversity (Shannon H ' = 2.61-2.64; Pielou's J ' > 0.91) and log-normal rank-abundance distributions, confirming intact community structure. Species inventories were near-complete (Chao1: 90%-95%). Total Charaxes abundance declined by 61% from intact to heavily disturbed sites (Kruskal-Wallis H(2) = 14.32, p = 0.001, eta(2) = 0.72), with three forest specialists, Charaxes cithaeron, C. violetta and C. zoolina, declining by 72%-76% and showing strong fidelity to closed-canopy habitats (79%-84% of captures under shade). Canonical correspondence analysis explained 52.3% of species-environment variation (F-(5,F-6) = 3.14, p = 0.002, 999 permutations), with Prunus africana density (r = 0.68), canopy cover (r = 0.64) and host plant richness (r = 0.61) as the strongest predictors. Bioindicator evaluation using IndVal analysis identified four robust candidate species (IndVal 68.7-76.3, p < 0.005), and significant compositional turnover between forest blocks (beta SIM = 0.38) confirmed that each contributes uniquely to regional diversity. Based on these findings, we recommend equal conservation investment in both forests, maintaining canopy cover above 70%, targeted protection and enrichment planting of P. africana and Turraea stapfiana, and a tiered monitoring protocol using the three specialist species as early-warning bioindicators of forest deterioration.

Although there is an emerging evidence base on the impact of planned donor transitions from HIV programs, there is little research exploring the effects of abrupt cessation of donor aid for HIV programs. We sought to examine the early impacts of PEPFAR funding freeze announced on 20th January 2025 on HIV service delivery in Mid-western Uganda. We conducted a qualitative study in the Fort Portal region of mid-Western Uganda, involving 84 participants. In-depth interviews were conducted with 36 health workers in eight purposively selected HIV clinics. Six focus group discussions with a total of 48 participants were conducted with people with HIV (PWH). Data were analyzed by thematic approach. Four broad themes emerged in our analysis (1) There was uncertainty and confusion across the HIV service delivery landscape right from national-level HIV sector oversight to frontline service delivery. (2) PWH started ‘buffer stocking’ of antiretrovirals which contributed to stock-outs at participating facilities. (3) There was discontinuation of multiple HIV services. The discontinued HIV services include HIV prevention programs, viral load testing, services targeting ‘Key Populations’ and, community outreach for enhancing adherence to HIV/TB treatment including medication distribution through private retail pharmacies which ceased. (4) The loss of PEPFAR-salaried HIV workforce had ripple effects. These include disruptions in routine operations at HIV clinics, sub-national governance mechanisms for HIV services delivery unraveled and loss of PEPFAR-supported community health workers resulted in cessation of community outreach activities while loss of data clerks impeded routine HIV data capture. The abrupt cessation of PEPFAR funding resulted in widespread disruptions to HIV service delivery including discontinuation of multiple HIV services at participating facilities. Our findings highlight the need for planned donor transitions and the need of strengthening the financial, technical, and management capacity of recipient governments for managing previously donor-funded HIV services. Further research on the medium- to long-term impacts of PEPFAR funding freeze is warranted. Not applicable.