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Pesticide treated sawdust and early planting salvage maize yield through reduction of termite infestation and damage
(Advances in Agriculture, 2026-01-24) Kagoda, Frank; Denis Najjoma; Emmanuel Basena; Joshua Pyan Mudingotto; Akasairi Ocwa; Herbert L. Talwana
Termites (Isoptera: Termitidae) infestation is a key constraint to maize production in Uganda. This study was conducted to determine the effect of integrating planting time and imidacloprid-treated wood sawdust in the control of termites. Three experiments were established at Ikulwe Satellite Station in Mayuge in 2017B, 2018A, and 2018B in a randomized complete block design (RCBD) with three replications. Planting time was at the onset of rains and 2 weeks later. The treatment regime comprised (i) sawdust treated with imidacloprid (IM + SD), (ii) sawdust only (SD), (iii) imidacloprid only (IM), and (iv) the control (no treatment). Data were collected on the number of lodged plants, termite numbers, and grain yield, among other parameters and subsequently analyzed. The results revealed that the use of imidacloprid-treated wood sawdust and early planting significantly reduces termite infestation. This was justified by the significantly lower (p < 0.05) average population of termites (442 termites ha−1), the negligible number of lodged plants (293 plants ha−1), and just a handful of damaged cobs (167 cobs ha−1) compared to 3455 termites ha−1, 760 lodged plants ha−1, and 782 damaged cobs ha−1, respectively, in the untreated sawdust control. Grain yield of 5.0 t ha−1 was realized under imidacloprid-treated sawdust in early planting, compared to only 3.5 t ha−1 under imidacloprid treated sawdust but in late planting. Therefore, the use of imidacloprid-treated sawdust as a bait to control termites damage and early planting of maize proved effective in reducing termite prevalence, infestation, and consequently optimized maize yield.
Econometric analysis of efficiency among public health center III facilities in kigezi subregion Uganda
(Taylor & Francis Group, 2025-12) Innocent Mugisha; Kenneth Tindimwebwa; Lillian Namubiru; Khder Alakkari; Bushra Ali; Maad M. Mijwil; Mostafa Abotaleb
The scarcity of healthcare resources and shortfalls in budget allocations for the health sector in the Kigezi subregion calls for efficient utilization of inputs, measurement, and reporting of the performance of Health Center III facilities. The purpose of the study is to answer the question; what are the efficiency and slack levels among facilities? Data from a sample of 30 facilities containing health inputs and outputs were obtained from the Uganda Bureau of Statistics for the financial year 2022/2023. A constant returns to scale output-oriented data envelopment analysis technique is adopted for the analysis. Results reveal that 47% of the facilities were technically efficient, and the score averaged 72%. This implies that the facilities need to improve resource utilization by 28% to become technically efficient. Mean scale efficiency stood at 97.75%, implying that 2.25% of the scale-inefficient facilities waste more input resources due to their size. Slack values were registered. There were 16 benchmark facilities identified for reference because of their best practices. Inefficient healthcare facilities should be made to improve their technical and scale efficiency levels by reducing the resources employed as well as increasing the output that they produce.
Revisiting the exoplanet radius valley with host stars from SWEET-Cat
(Astronomy & Astrophysics manuscript, 2026-01-21) Kamulali, Juma; Vardan Adibekyan; Benard Nsamba; Sergio G. Sousa; Tiago. L. Campante; Achim Weiss; Bridget Kabugho; Nuno Moedas; Nuno C. Santos; Otto Trust
Context.
The radius valley, a deficit in the number of planets with radii around 2 R⊕, was observed among exoplanets with sizes ≲ 5 R⊕ and orbital periods < 100 days by NASA’s Kepler mission. This feature separates two distinct populations: super-Earths (rocky planets with radii ≲ 1.9 R⊕) and sub-Neptunes (planets with substantial volatile envelopes and radii ≳ 2 R⊕). The valley has been proposed to stem from either planet formation conditions or evolutionary atmospheric loss processes. Disentangling these mechanisms has led to numerous studies of population-level trends, although the resulting interpretations remain sensitive to sample selection and the robustness of host-star parameters.
Aims.
To re-examine the existence and depth of the radius valley, and how its location varies with orbital period, incident flux, stellar
mass, and stellar age.
Methods. We derived robust fundamental stellar parameters of 1,221 main-sequence stars (hosting 1,405 confirmed planets) from the SWEET-Cat database using a grid-based machine-learning tool (MAISTEP), which incorporates effective temperatures and metallicities from spectroscopy, as well as Gaia-based luminosities. Our analysis covers stars with effective temperatures between 4400 – 7500 K (FGK spectral types) and estimated radii between 0.62 – 2.75 R⊙. We attained an average uncertainty of 2% in stellar radius and 2% in mass. Combining the updated stellar radii with planet-to-star radius ratios from the NASA Exoplanet Archive, we recomputed the planetary radii achieving an average uncertainty of 5%.
Results.
Our findings confirm a partially filled planet radius valley near 2 R⊕. The valley depends on orbital period, incident flux, and stellar mass, with slopes of −0.12+0.02−0.01, 0.10+0.02−0.03, 0.19+0.09−0.07, respectively. We also find a stronger mass-dependent trend in average sizes of sub-Neptunes than super-Earths of slopes 0.17+0.04−0.04 and 0.11+0.05−0.05, respectively. With stellar age, the super-Earth/sub-Neptune number ratio increases from 0.51+0.11−0.08 (< 3 Gyr) to 0.64+0.11−0.11 (≥ 3 Gyr). In addition, the valley becomes shallower and shifts to larger radii, indicating age-dependent evolution in planet sizes. A four-dimensional (planet radius, orbital period, stellar mass, and stellar age) linear fit of the valley produces slopes in orbital period and stellar mass that are consistent with the results of the two-dimensional analyses, and a weaker slope of 0.07+0.03−0.04 in stellar age.
Conclusions.
The valley’s shift and shallowing over gigayear timescales point to prolonged atmospheric loss, which is consistent with a core-powered mass-loss scenario. Our findings also highlight the importance of stellar age in the interpretation of exoplanet demographics and motivate improved age determinations, as expected from future missions like PLATO.
Land-use change and small-mammal diversity in and around African mountain forest reserves: consistent loss of habitat specialists and critical gaps in altitudinal, long-term, and landscape-scale research- a review
(East African Journal of Environment and Natural Resources, 2026-01-23) Atwijukye, Dunstan; Turyahabwe Remigio; Isabirye Moses
Anthropogenic land-use change, such as agricultural intensification, selective logging, overgrazing, altered fire regimes, urbanisation, plantation forestry, and habitat fragmentation, have consistently favoured ecologically generalist small mammals while driving marked declines or local degradation of habitat-specialist species (particularly forest-dependent rodents and shrews) across Africa. This systematic review synthesised 37 independent field studies (2002–2021) and reveals a striking continent-wide pattern: natural and lightly disturbed habitats sustain higher small-mammal richness and specialist taxa, whereas intensive disturbance shifts assemblages toward a small set of generalist species, often with seasonal peaks tied to rainfall or crops. Despite this convergence, virtually all studies share the same critical methodological gaps: no altitudinal transects, no long-term (multi-year) monitoring, no landscape-connectivity or matrix-permeability analyses, limited multi-seasonal replication, and no assessment of population sustainability or resilience. Consequently, reported specialist declines may reflect temporary dispersal or seasonal lows rather than irreversible extinction, while the long-term viability of dominant generalists remains unknown. The current evidence base is therefore predominantly short-term and snapshot-based, severely limiting its predictive value for conservation under accelerating land-use and climate change. Robust future research requires routine incorporation of elevational gradients, multi-annual monitoring, landscape-scale connectivity analyses, full seasonal coverage, and explicit tests of population persistence to secure Africa’s small-mammal diversity.
Compressive strength and cost-effectiveness of confined waste plastic bottle brick masonry walls
(International Journal of Sustainable Engineering, 2026-01-22) Masaba, Emmison Eric; Kyakula, Micheal; Ssenyondo, Vicent
Uganda faces a substantial housing deficit, and escalating construction costs resulting from unsustainable extraction of construction materials and inadequate management of plastic and sawdust waste. This study evaluates the compressive strength and cost effectiveness of Plastic Bottle Brick (PBB) masonry walls as a potential substitute for conventional concrete block walls in Mbale City, Uganda. The work specifically addresses the limited empirical evidence concerning the behaviour of vertically oriented confined PBB units incorporating uncompressed air (EB), sawdust (SD) and pit sand (PS). Compressive strength testing showed that PS walls achieved a strength of 0.6 ± 0.02 MPa, comparable to hollow concrete block (HCB) walls (0.6 ± 0.06 MPa). SD and EB walls exhibited lower strengths of 0.3 ± 0.05 MPa and 0.3 ± 0.03 MPa, respectively, below the strength of solid concrete block (SCB) walls (0.8 ± 0.03 MPa). All PBB walls demonstrated higher failure strains (1.8–2.0%) than concrete block walls (1.0–1.2%). The cost-benefit analysis considering materials, labour, time utilisation and carbon emissions costs found that EB blocks were the most economical (USD 3.22/UGX 11,694), while SCB were the least economical (USD 7.97). PBB production was commercially feasible, with casting time only 17% slower than conventional block production.