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Item Anthropogenic footprint and ecological risk assessment of organochlorine pesticides and polychlorinated biphenyls in sediments from Lake Victoria, East Africa(Elsevier, 2025-12-15) Kagoya, Afuwa; Arinaitwe, Kenneth; Odongo, Silver; Sifuna, Douglas; Matovu, Henry; Matsiko, Julius; Muhwezi, Godfrey; ˇSp´anik, Ivan; Kato, Charles Drago; Sillanpa, Mika; Ssebugere, PatrickLake Victoria, the world’s second-largest freshwater lake, continues to face pressure from anthropogenic activities in its catchment area, releasing pollutants, which are ultimately trapped in the sediment core, thereby posing threats to aquatic organisms. This study quantified thirteen organochlorine pesticides (OCPs) and ten polychlorinated biphenyls (PCBs) in sediments from the Uganda, Kenya, and Tanzania sides of Lake Victoria using soxhlet method, fractionation column and GC–MS/MS analysis. Total (∑13) OCPs levels were up to 412, 148, and 522 µg kg-1 dry weight (d.w), and 12.1, 8.69 and 9.87 µg kg-1 dw for total (∑10) PCBs for sediments from Uganda, Kenya, and Tanzania, respectively. Diagnostic ratios suggested past and ongoing use of OCPs while principal component analysis confirmed that OCP profiles were mainly due to their application in controlling pests in agriculture and public health programs, and PCB congeners were largely due to volatilization, degradation of higher PCBs into lighter PCBs, improper waste disposal of old transformers, hydraulic fluids, plasticizers, and capacitors. Ecological risk assessment highlighted that the PCB levels in sediments were below threshold effect and probable effect levels, but p,p′-DDD, and lindane were likely to pose adverse effects to sediment-dwelling organisms in Lake Victoria. These results imply persistent pollutant loads in Lake Victoria, and consequently, a need for its enhanced management.Item Genome-wide identification and expression analysis of the Small Ubiquitin-like Modifier (SUMO) gene family in Triticum aestivum L.(Springer Nature, 2025-12-11) Kesawa, Mahipal Singh; Kherawat, Bhagwat Singh; Reager, Madan Lal; Badu, Meenakshi; Kabi, Mandakini; Mohanty, Ankita; Raju, Kalidindi Krishnam; Lenka, Sangram K.; Alamery, Salman Freeh; Al-ateeq, Talak K.; Masika, Fred Bwayo; Hong, Choo BongBackground: Post-translational modification of proteins by SUMO is critical for a wide range of cellular and developmental processes. Although SUMO proteins have been extensively studied in animals and, to some extent, in Arabidopsis, their precise functions in other crop plants are still largely unknown. Results: In this research, we identified 31 TaSUMO genes in genome of wheat. Phylogenetic tree unveiled that genes clustered into thirteen subfamilies. Chromosomal mapping unveiled the dispersal of 31 TaSUMO genes across 11 wheat chromosomes. The eleven pairs of duplicated gene were identified in the SUMO family. Ka/Ks ratio revealed that 8 duplicated TaSUMO genes went through purifying purification. Furthermore, it was noted that TaSUMO genes displayed significant conversation in their gene structure. In addition, analysis of promoters uncovered the presence of numerous cis-regulatory elements in the promoter region of the TaSUMO genes. The differential expression patterns were observed among TaSUMO family members across various tissues and in response to multifaceted stress conditions. Moreover, this investigation explored the miRNAs targeted to TaSUMO genes and expression profile in various tissues. Conclusion: Thus, the results of this study establish a strong basis for further investigation of the functions of TaSUMO genes across different tissues, developmental stages, phytohormone responses, and diverse stress in wheat.Item Deformations and simultaneous resolution of determinantal surfaces(Oxford University Press, 2025-11-25) Makonzi, BrianThis paper uses reconstruction algebras to construct simultaneous resolution of determinantal surfaces. The main new difference to the classical case is that, in addition to the quiver of the reconstruction algebra, certain non-commutative relations, namely those of the canonical algebra of Ringel, are required. All the relations of the reconstruction algebra except the canonical relation are then deformed, and these deformed relations together with variation of the geometric invariant theory (GIT) quotient achieve the simultaneous resolution.Item Unraveling the genetic basis of fertility restoration in hybrid rice: insights from CMS lines and male restorer analyses(Taylor & Francis, 2025-10-21) Sharmaa, Deepak D.; Patel, V. P.; Chaudhary, Ankit; Modha, K.G.; Parekh, V.B.; Naik, Islavath Suresh; Masika, Fred Bwayo; Kesawat, Mahipal SinghRice (Oryza sativa L.) serves as the staple food for over half of the global population. To address the pressing need for increased rice production, hybrid rice technology leverages the concept of hybrid vigor, or heterosis, achieving a 15–20% yield advantage over traditional varieties. This study focuses on developing hybrid varieties through the cytoplasmic genetic male sterility (CGMS) mechanism. It explores the genetic inheritance of fertility restoration in two distinct CMS lines, IR58025A (WA) and RTN13A (Gambiaca), using 165 diverse male lines. The study successfully generated F1 hybrids and evaluated them for pollen and spikelet fertility, identifying NVSR 2965 and NVSR 3280 as effective restorers, with fertility rates surpassing 90%. Analysis of the F2 generations from these crosses revealed that fertility restoration is controlled by two dominant genes, Rf3 and Rf4, which interact epistatically. The cross IR58025A × NVSR 2965 exhibited a 12:3:1 segregation pattern, suggesting simple dominance with a masking effect, while RTN13A × NVSR 3280 showed a 15:1 ratio, indicating duplicate dominance. These findings enhance our understanding of the genetic mechanisms underlying fertility restoration and provide valuable insights for applying marker-assisted selection and breeding strategies to develop high-yield hybrid rice varieties.Item Effect of exposure to malaria messages on insecticide-treated net use among women and under-five children in Uganda: a propensity score matched analysis(Springer Nature, 2025-11-10) Mwebesa, Edson; Agbi, Delight Mawufemor; Iha, Daniel Thoya; Agasa, Lameck Ondieki; Mwangi, AnnBackground: Malaria remains a global public health issue, with almost 2.5 million cases and more than 0.6 million deaths each year, of which women and children remain disproportionately affected. Insecticide-treated nets (ITNs) are a cornerstone of malaria prevention in endemic malaria regions. Malaria messages (MM) are intended for positive and measurable social, attitude, and behavioural change towards malaria prevention uptake. However, their impact on insecticide-treated nets (ITNs) use has not been sufficiently investigated through rigorous statistical approaches. This study investigated the effect of MM on ITN use among women and children under five years in Uganda using Propensity Score Matched Analysis (PSMA). Methods: The study utilized the Uganda Malaria Indicator Survey (UMIS) 2018 -19 data. Women (n = 8868) and children (n = 6915) datasets were extracted from Individual Women’s and Children’s Data, respectively. The children’s dataset included data on interviewed women (caregivers), household indicators and under-five children’s data, while the women's dataset contains records of every eligible woman in selected households. Propensity score-matched analysis (PSMA) was utilized to identify the effect of the MM (intervention) on ITN use (outcome) among women of reproductive age and children under five in Uganda. Results: The results revealed that 69.3 [95% CI: 67.2, 71.2] of the women and 71.8 [95% CI: 69.1, 74.4] of the children under five years slept under a mosquito bed net the night preceding the survey. The results further revealed a significant and positive effect of exposure to malaria messages on ITN use among exposed women [Average Treatment Effect of the Treated (ATT) = 5.1%, 95% CI: 1.5–8.9%] and under-five children of exposed women [ATT = 4.3%, 95% CI: 1.0–7.6%]. Conclusion: Effective and relevant behavioural change communications, such as malaria messages, are an effective way of influencing the use of ITN. Such an intervention may reduce malaria endemicity, morbidity, and mortality in Uganda.Item Rapid detection of Helicobacter pylori and its virulence genes by fluorescence-chromogenic double-indicator LAMP (FC-LAMP)(Elsevier, 2025-10-15) Liu, Yanghe; Yin, Sijie; Chen, Shiyue; Zhang, Chunlei; Lubanga, Nasifu; Tai, Ping; Xiong, Mengqiu; Fan, Boyue; Yang, Xincheng; Xia, Xinyi; Hou, Panfei; He, BangshunHelicobacter pylori (H. pylori) is a risk factor of gastrointestinal diseases. Vacuolating cytotoxin A (VacA) is a key component of the pathogenicity of H. pylori for gastric diseases, and detection for virulence genotypes facilitates precise clinical diagnosis and individual treatment. Hence, a more accurate, convenient, and highly sensitive detection method is urgently needed. In this study, we developed a method based on fluorescence-colorimetric dual-indicator loop-mediated isothermal amplification (FC-LAMP), allowing for naked-eye readout, using a constant temperature water bath within 40 min in clinical settings. Such an excellent sensitivity and specificity, and user-friendly operation approach achieved a limit of 10−6 ng/μl for 16 s rRNA detection of H. pylori, and 100 % specificity for 55 clinical gastric fluid samples compared with the immunofluorescence staining (IFS) and quantitative polymerase chain reaction (qPCR) as reference methods. In short, this study offers a new strategy for detection of H. pylori and its virulence genotype in primary hospitals and in limited resources settings, facilitating individualized precision eradication of H. pylori.Item Effect of exposure to malaria messages on insecticide-treated net use among women and under-five children in Uganda: a propensity score matched analysis(Springer Nature, 2025-11-10) Mwebesa, Edson; Agbi, Delight Mawufemor; Iha, Daniel Thoya; Agasa, Lameck Ondieki; Mwangi, AnnBackground Malaria remains a global public health issue, with almost 2.5 million cases and more than 0.6 million deaths each year, of which women and children remain disproportionately affected. Insecticide-treated nets (ITNs) are a cornerstone of malaria prevention in endemic malaria regions. Malaria messages (MM) are intended for positive and measurable social, attitude, and behavioural change towards malaria prevention uptake. However, their impact on insecticide-treated nets (ITNs) use has not been sufficiently investigated through rigorous statistical approaches. This study investigated the effect of MM on ITN use among women and children under five years in Uganda using Propensity Score Matched Analysis (PSMA). Methods The study utilized the Uganda Malaria Indicator Survey (UMIS) 2018 -19 data. Women (n = 8868) and children (n = 6915) datasets were extracted from Individual Women’s and Children’s Data, respectively. The children’s dataset included data on interviewed women (caregivers), household indicators and under-five children’s data, while the women's dataset contains records of every eligible woman in selected households. Propensity score-matched analysis (PSMA) was utilized to identify the effect of the MM (intervention) on ITN use (outcome) among women of reproductive age and children under five in Uganda. Results The results revealed that 69.3 [95% CI: 67.2, 71.2] of the women and 71.8 [95% CI: 69.1, 74.4] of the children under five years slept under a mosquito bed net the night preceding the survey. The results further revealed a significant and positive effect of exposure to malaria messages on ITN use among exposed women [Average Treatment Effect of the Treated (ATT) = 5.1%, 95% CI: 1.5–8.9%] and under-five children of exposed women [ATT = 4.3%, 95% CI: 1.0–7.6%]. Conclusion Effective and relevant behavioural change communications, such as malaria messages, are an effective way of influencing the use of ITN. Such an intervention may reduce malaria endemicity, morbidity, and mortality in Uganda.Item Indigenous knowledge and plant speciesused as mosquito repellents in the West NileSubregion, Uganda(Springer Nature, 2025-11-07) Oloya, Benson; Andama, Morgan; Akwongo, Betty; Amagu, Paulino; Opoke, Robert; Candia, Milton; Samanya, Rehemah; Taban, Philliam; Okello, Emoses Agen; Anywar, GodwinBackground Female Anopheles mosquitoes are the primary vectors for malaria transmission within communities, significantly contributing to the high burden of malaria in Africa overall and Uganda specifically. Many tropical plants have insect-repellent properties and have traditionally been used in their native regions to prevent mosquito bites. Methods A cross-sectional ethnobotanical survey was conducted between January 2025 and May 2025 in five districts of the West Nile Subregion: Adjumani, Moyo, Madi-Okollo, Pakwach, and Obongi. Semi-structured questionnaires were used to collect data on indigenous knowledge about mosquito repellents from 57 respondents, who were selected through purposive and snowball sampling techniques. The ethnobotanical data were analyzed using descriptive statistics, the informant consensus factor, and preference ranking. Results A total of 42 plant species from 40 genera and 25 families were documented as being used to repel mosquitoes. The plants most commonly used for this purpose were: Azadirachta indica A.Juss. (9), Boswellia papyrifera (Caill.) (7), Aeschynomene americana L. (6), Mesosphaerum suaveolens (L.) Kuntze. (6), and Ocimum gratissimum L. (5). The most common indigenous method for repelling mosquitoes involves burning either dry cow dung (32%) or dry goat droppings (20%). Most of the plant species belong to the families Fabaceae (10), Lamiaceae (4), and Asteraceae (3). The majority of the plant species used were trees (43%) and herbs (42%), with leaves (42%) and seeds (12%) being the most frequently used plant parts. Except for Cymbopogon citratus (DC.) Stapf and M. suaveolens, which are used as live plants for repelling mosquitoes, all other plant species used were prepared by burning or smoking indoors. Conclusions Communities in the West Nile Subregion, especially those living along the River Nile, possess rich indigenous knowledge and practices used to repel mosquitoes in their efforts to control deadly malaria.Item Radiation-induced degradation in the properties of pristine anddouble-walled carbon nanotube-enhancedpoly (2,5-benzimidazole) polymers for radiation shielding in the LEO(Elsevier, 2025-09-01) Oryema, Bosco; Square, Lynndle; Ellis, ErnstDegradation in the properties of polymer-based materials in space environments is a critical challenge for developing lightweight radiation shielding solutions. In this paper, a comparative study of the impacts of helium ion (He+) irradiation one of the ion species in the Low Earth Orbit (LEO) environment on the structural and optical properties of pristine and 1.0 wt% double-walled carbon nanotube (DWCNT)-enhanced poly(2,5-benzimidazole) (ABPBI) polymers for LEO radiation shielding applications was conducted. The two polymer categories were separately chemically prepared in the laboratory, moulded, dried, and cut into 1 cm × 1 cm pieces, and bombarded with 0.35 MeV He+ ions at varying fluences. The Ultraviolet–Visible-Near-Infrared (UV–Vis-NIR) optical analyses of the polymers following the ion bombardment revealed that He+ irradiation considerably raises the Urbach energy and decreases the optical bandgap, indicating a rise in electronic defects and structural disorder. On the other hand, the Fourier Transform Infrared (FTIR), Atomic Force Microscopy (AFM), and X-ray Diffraction (XRD) analyses revealed higher levels of structural degradation in the pristine ABPBI samples, suggesting changes brought about by irradiation-induced oxidation and chain scission processes. In contrast, the 1.0 wt% DWCNT-ABPBI composite demonstrated improved optical and structural integrity, retention, and resistance to He+ ion-induced damage. According to the results, 1.0 wt% DWCNT reinforcement reduces radiation-induced deterioration and offers more protection from energetic ion exposure in the LEO settings. Thus, this work highlights the distinct impact of He+ ion interactions with ABPBI and the effectiveness of DWCNT inclusion in improving polymer resilience, and it contributes to the fundamental understanding of the polymer composite for radiation shielding applications.Item An explainable AI framework for neonatal mortality risk prediction in Kenya: Enhancing clinical decisions with machine learning(Science Publishing Group, 2025-09-30) Lumumba, Victor Wandera; Muriithi, Dennis Kariuki; Njoroge, Elizabeth Wambui; Langat, Amos Kipkorir; Mwebesa, Edson; Wanyama, Maureen AmbasaNeonatal mortality remains a critical public health challenge in Kenya, with a rate of 21 per 1,000 live births—well above the SDG 3.2 target. While machine learning (ML) offers potential for risk prediction, most models lack transparency and clinical interpretability, limiting their adoption in low-resource settings. This study presents an explainable AI (XAI) framework for predicting neonatal mortality using Kenya Demographic and Health Survey (KDHS) data (N = 2,000), with a focus on model accuracy, fairness, and clinical relevance. Six ML models—Logistic Regression (LR), KNN, SVM, Naïve Bayes, Random Forest, and XG-Boost—were trained and evaluated using in-sample, out-of-sample, and balanced datasets, with performance assessed via AUC, F1-score, sensitivity, specificity, and Cohen’s Kappa. To address class imbalance and enhance generalizability, synthetic oversampling and rigorous cross-validation were applied. Post-balancing, LR achieved optimal performance (AUC = 1.0, κ = 0.98, F1 = 0.987), with SVM (AUC = 0.995) and XG-Boost (AUC = 0.982) also showing higher performance. SHAP and model breakdown analyses identified Apgar scores (at 1st and 5th minutes), birth weight, maternal health, and prenatal visit frequency as key predictors. Fairness assessments across socioeconomic subgroups indicated minimal bias (DIR > 0.8). The integration of XAI enhances transparency, supports clinician trust, and enables equitable decision-making. This framework bridges the gap between predictive accuracy and clinical usability, offering a scalable tool for early intervention. Policy recommendations include embedding this XAI-enhanced model into antenatal care systems to support evidence-based decisions and accelerate progress toward neonatal survival goals in resource-limited settings.Item Value of hs‑cTnT, sST2, and Lp‑PLA2 in the classification of acute coronary syndrome(Spandidos Publications, 2025-08-22) Peng, Hongxin; Lubanga, Nasifu; Sun, Cong; He, Bangshun; Mei, Yan‑Ping; Wang, YishanThe present study aimed to assess the value of high‑sensitivity cardiac troponin T (hs‑cTnT), soluble suppression of tumorigenicity 2 protein (sST2) and lipoprotein‑associated phospholipase A2 (Lp‑PLA2) in the classification of acute coronary syndrome (ACS). A total of 236 patients diagnosed with ACS were enrolled in this retrospective study and were further divided into the non‑ST‑segment‑elevation (NSTE)‑ACS group (n=183) and ST‑segment elevation myocardial infarction (STEMI) group (n=53). The three biomarkers (hs‑cTnT, sST2 and Lp‑PLA2) were measured by electrochemiluminescence. The diagnostic performance of each biomarker in differentiating ACS subtypes was evaluated through receiver operating characteristic curve analysis. The DeLong test was applied to compare the discriminatory abilities of the different markers. The binary logistic regression model was employed to analyze the factors influencing ACS classification. The levels of hs‑cTnT and sST2 in males were significantly higher in the STEMI group than in the NSTE‑ACS group (P<0.05). hs‑cTnT [odds ratio (OR)=1.010, 95%CI: 1.007‑1.014] and sST2 (OR=1.022, 95%CI: 1.011‑1.033) were identified as good predictors for distinguishing STEMI from NSTE‑ACS, whereas Lp‑PLA2 (P=0.470) was not a suitable biomarker to discriminate between the two types of ACS. Additionally, the diagnostic efficacy of hs‑cTnT [area under curve (AUC=0.861)] and the combination of hs‑cTnT and sST2 (AUC=0.863) was higher than that of sST2 alone (AUC=0.833, P<0.05). In conclusion, these findings illustrated that hs‑cTnT and sST2 are promising biomarkers to classify patients with ACS. Compared with sST2 alone, hs‑cTnT and its combined detection demonstrate superior diagnostic efficiency in identifying ACS.Item Acute and sub-acute toxicity assessment of methanolic stem bark extract of Khaya anthotheca (Meliaceae) in Wistar rats(Springer Nature, 2025-08-29) Akwongo, Betty; Kakudidi, Esezah K.; Nsubuga, Anthony M.; Andama, Morgan; Namaganda, Mary; Tugume, Patience; Asiimwe, Savina; Anywar, Godwin; Katuura, EstherBackground: Khaya anthotheca (Meliaceae) is a medicinal plant with a wide range of therapeutic properties attributable mainly to the diverse limonoids it contains. Different parts of the plant are used in traditional health care for treatment of various diseases including candidiasis. However, inadequate information on its safety prompted this particular study. Methods: Acute toxicity was assessed according to OECD guidelines 425 in female rats administered with single oral doses of 2000 and 5000 mg/kg body weight (b.wt), and monitored for 14 days for any sign of toxicity and mortality. Sub-acute toxicity was evaluated in both male and female rats following OECD guideline 407, and were administered with extract doses of 500, 250 and 125 mg/kg b.wt repeatedly for 28 days. Body weights were measured weekly, while food and water intake were measured daily. Blood for biochemistry, hematology, and organs for histopathology were collected at the end of the experimental period. Data were analyzed using one-way ANOVA followed by Turkey’s post hoc tests, and repeated measures ANOVA. Results: Acute toxicity showed no mortality, with half-lethal dose (LD50) being greater than 5000 mg/kg b.wt. For sub-acute toxicity, both male and female rats presented significant increase in food and water consumption, increased body weight with increasing time and extract doses (p < 0.05). The 500 mg/kg dosed female rats showed significant increase in stomach weights and alanine aminotransferase (ALT), while renal function marker of chloride ions (Cl−) decreased. Male rats showed dose-dependent significant rise in albumin (ALB) (p = 0.024). For both male and female rats, prolonged use of high extract doses of 250 and 500 mg/kg b.wt for 28 days were toxic to the stomach and liver. Conclusions: The methanolic stem bark extract of K. anthotheca is practically non-toxic at acute dose of 5000 mg/kg b.wt, and safe for clinical use at low sub-acute doses of 125 mg/kg b.wt. However, long-term administration of high extract doses above 125 mg/kg was toxic to mainly the liver and stomach. Thus, long-term administration of high dosage of methanol stem bark extract of K. anthotheca, and phytomedicine development should be done with cautions of potential side effects.Item In vitro antifungal activities of medicinal plants used for treatment of candidiasis in Pader district, Northern Uganda(Springer Nature, 2024-11-13) Akwongo, Betty; Kakudidi, Esezah K.; Nsubuga, Anthony M.; Andama, Morgan; Namaganda, Mary; Tugume, Patience; Asiimwe, Savina; Anywar, Godwin; Katuura, EstherBackground The emergence of multidrug resistant Candida species to available drugs has led to renewed interest in the use of herbal medicines globally. This study scientifically verified antifungal effectiveness of five commonly used plant species in Pader district, against selected pathogenic candida strains. Methods Powdered roots of Momordica foetida, Sansevieria dawei and Distimake dissectus; and stem barks of Khaya anthotheca and Mitragyna rubrostipulata were extracted sequentially using petroleum ether and methanol, respectively; and total water extraction at 24.4 °C (maceration), 60 °C (decoction) and boiling water at 87 °C (hot water infusion). Extracts and their combinations, positive controls (amphotericin B, and fluconazole) and negative control (80% dimethyl sulfoxide, verified to be tolerable concentration to the tested Candida species) were screened and verified for their antifungal activity against Candida albicans (ATCC: American Type Culture Collection reference strain 10231, ATCC 90028, 0770a and 0796), C. glabrata (VVc 004, ATCC 2950) and C. tropicalis (ATCC 750 and 0210) using agar well diffusion and broth micro-dilution, respectively. Results Aqueous extract (24.4 °C) of M. rubrostipulata (ZOI: 18.00 ± 1.00 to 38.33 ± 0.17; MIC: 3.13 ± 0.00 to 20.83 ± 4.17; MFC: 12.50 ± 0.00 to 200.00 ± 0.00), methanol extract of K. anthotheca (10.11 ± 0.31 to 15.11 ± 0.65; 1.04 ± 0.26 to 12.50 ± 0.00; 12.50 ± 0.00 to 100.00 ± 0.00), and combination of aqueous extract (60 °C) of D. dissectus + methanol extract of K. anthotheca (7.89 ± 0.26 to 19.67 ± 0.37; 0.78 ± 0.00 to 50.00 ± 0.00; 12.50 ± 0.00 to 200.00 ± 0.00) exhibited broad spectrum antifungal activities and were fungistatic against all tested Candida species, which comprised 8 clinical/control and susceptible/resistant strains. None of the conventional drugs used demonstrated broad spectrum antifungal activity across all tested Candida species/strains. Conclusion Methanol extract of K. anthotheca, aqueous extract (24.4 °C) of M. rubrostipulata, and combination of aqueous extract (60 °C) of D. dissectus + methanol extract of K. anthotheca could be effective in the treatment of candidiasis. They demonstrated potential broad spectrum antifungal activity against different species and strains of tested Candida than the fluconazole and amphotericin B drugs. Their fungistatic nature showed their ability to inhibit fungal growth. Hence, these extracts/extract combination can offer better treatment option for candidiasis if they are standardized and also their active curative compounds isolated and made into antifungal drugs.Item How the chemical composition of solids influences the formation of planetesimals(EDP Sciences, 2025-07-11) Xenos, Konstantinos Odysseas; Bitsch, Bertram; Andama, GeoffreyThe formation of planetesimals is a necessary step for the formation of planets. While several methods exist that can explain the formation of planetesimals, an increase in the local dust-to-gas ratio above unity is a strong requirement to trigger the collapse of the pebble cloud to form planetesimals. One prime location for this to happen is at the water-ice line, where large water-rich pebbles evaporate and release their smaller silicate cores, resulting in an increase in the local dust-to-gas ratio originating from the different inward velocities of the large and small pebbles. While previous work indicated that planetesimal formation becomes very challenging at overall dustto-gas ratios below 0.6%, in line with the occurrence of close-in super-Earths, it is unclear how the overall disc composition influences the formation of planetesimals. Observations of stellar abundances not only indicate a decrease in the overall C/O ratio for low metallicity stars, they also show a large spread in the C/O ratios. However, the C/O ratio sets the abundance of water ice within the disc. Using the 1D numerical disc evolution code chemcomp, we simulated protoplanetary discs with varying C/O ratios and dust-to-gas ratios over a 3 Myr timescale. Planetesimal formation is modelled by implementing conditions based on dust-gas dynamics and pebble fragmentation. Our results confirm that planetesimal formation is highly dependent on disc metallicity with lower metallicity discs forming significantly fewer planetesimals. We find that a decreased carbon fraction generally enhances planetesimal formation, while a higher carbon fraction suppresses it due to a reduced water abundance at the same dust-to-gas ratio. The opposite is the case with the oxygen ratio, where larger oxygen fractions allow a more efficient formation of planetesimals at the same overall dust-to-gas ratio. Consequently we make the prediction that planets around low metallicity stars should be more common if the stars have low C/O ratios, especially when their oxygen abundance is increased compared to other elements, testable through observations. Our simulations thus open a pathway to understanding whether the composition of the planet-forming material influences the growth of planets.Item Acute and sub‑acute toxicity assessment of methanolic stem bark extract of Khaya anthotheca (Meliaceae) in Wistar rats(Springer Nature, 2025-08-29) Akwongo, Betty; Kakudidi, Esezah K.; Nsubuga, Anthony M.; Andama, Morgan; Namaganda, Mary; Tugume, Patience; Asiimwe, Savina; Anywar, Godwin; Katuura, EstherBackground: Khaya anthotheca (Meliaceae) is a medicinal plant with a wide range of therapeutic properties attributable mainly to the diverse limonoids it contains. Different parts of the plant are used in traditional health care for treatment of various diseases including candidiasis. However, inadequate information on its safety prompted this particular study. Methods: Acute toxicity was assessed according to OECD guidelines 425 in female rats administered with single oral doses of 2000 and 5000 mg/kg body weight (b.wt), and monitored for 14 days for any sign of toxicity and mortality. Sub-acute toxicity was evaluated in both male and female rats following OECD guideline 407, and were administered with extract doses of 500, 250 and 125 mg/kg b.wt repeatedly for 28 days. Body weights were measured weekly, while food and water intake were measured daily. Blood for biochemistry, hematology, and organs for histopathology were collected at the end of the experimental period. Data were analyzed using one-way ANOVA followed by Turkey’s post hoc tests, and repeated measures ANOVA. Results: Acute toxicity showed no mortality, with half-lethal dose (LD50) being greater than 5000 mg/kg b.wt. For sub-acute toxicity, both male and female rats presented significant increase in food and water consumption, increased body weight with increasing time and extract doses (p < 0.05). The 500 mg/kg dosed female rats showed significant increase in stomach weights and alanine aminotransferase (ALT), while renal function marker of chloride ions (Cl−) decreased. Male rats showed dose-dependent significant rise in albumin (ALB) (p = 0.024). For both male and female rats, prolonged use of high extract doses of 250 and 500 mg/kg b.wt for 28 days were toxic to the stomach and liver. Conclusions: The methanolic stem bark extract of K. anthotheca is practically non-toxic at acute dose of 5000 mg/kg b.wt, and safe for clinical use at low sub-acute doses of 125 mg/kg b.wt. However, long-term administration of high extract doses above 125 mg/kg was toxic to mainly the liver and stomach. Thus, long-term administration of high dosage of methanol stem bark extract of K. anthotheca, and phytomedicine development should be done with cautions of potential side effects.Item Genome-wide survey of peptides containing tyrosine sulfation (PSY) gene family and potential PSY specific miRNA revealed their role in plant development and diverse stress conditions in rice (Oryza sativa L.).(Springer Nature, 2025-08-26) Kesawat, Mahipal Singh; Manohar, Swati; Anand, Ankit; Alamery, Salman Freeh; Badu, Meenakshi; Kabi, Mandakini; Mohanty, Ankita; Naik, Islavath Suresh; Kumar, Santosh; Kherawat, Bhagwat Singh; Kumar, Vinay; Lenka, Sangram K.; Verma, Shreya; Shrivastava, Harsha; Kumawat, Giriraj; Masika, Fred BwayoBackground Soybean is a fundamental oilseed crop, recognized for its notable protein and oil levels. Tyrosine Sulfation (PSY) genes play an essential role in plant growth, development, and responses to stress. However, the precise functions and mechanisms regulated by PSY are still being explored. Currently, there is insufficient information on the PSY gene family in soybean. Therefore, this study conducted a comprehensive genome-wide survey to detect and PSY family members were categorized in soybean. Results The phylogenetic analysis revealed that PSY family was categorized into nine distinct groups. Further, we precisely mapped the locations of the 12 GmPSY genes across seven soybean chromosomes. Examination of gene duplication revealed six pairs of duplicated genes within the PSY gene family in soybean. A consistent gene structure pattern was observed among GmPSY gene family members. The alignment of GmPSY protein amino acid sequences revealed a conserved PSY domain present in all proteins. Furthermore, RNA-seq data from the Soybean Expression Atlas revealed varying expression patterns of GmPSY genes across different tissues. To validate the expression profiles, qRT-PCR analysis was performed on selected GmPSY genes using root tissues from contrasting soybean accessions. In addition, identified eight out of the 12 GmPSY genes as targets for ten specific miRNAs. Moreover, we constructed a protein-protein interaction network to explore the connections between GmPSY and other soybean proteins. Conclusion Thus, these discoveries lay a robust groundwork for future research aimed at elucidating the specific roles of GmPSY members across different tissues and under various stress conditions in soybean.Item Nanoparticles in plant system: A comprehensive review on their role in diverse stress management and phytohormone signaling(Elsevier, 2025-08-19) Kumar, Vinay; Naik, Islavath Suresh; Das, Bimal; Singh, Anupama; Nayak, Prayasi; Mohapatra, Chinmayee; Debnath, Debanjana; Tripathy, Maitreyee; Behera, Kumareswar; Masika, Fred Bwayo; Manohar, Swati; Chung, Sang-Min; Kherawat, Bhagwat Singh; Hemalatha, Mamidi; Kesawat, Mahipal SinghClimate variability has led to significant environmental shifts in recent years, placing growing strain on agricultural systems worldwide. These environmental fluctuations have magnified the effects of abiotic and biotic stresses on plants, substantially hampering their growth and lowering crop productivity. To tackle these challenges, there is an urgent need for innovative and effective strategies that promote sustainable agricultural practices. Among emerging technologies, nanotechnology has attracted significant interest for its transformative potential in agriculture. The application of nanoscale materials including nanopesticides, nanofungicides, nanofertilizers, and nanoherbicides offers promising avenues for enhancing crop protection and boost productivity. Nanoparticles (NPs) exhibit unique physicochemical properties that allow for precise and targeted delivery of nutrients and protective agents, thereby improving both the quality and yield of crops under diverse stress conditions. Phytohormone signaling pathways comprise intricate biochemical networks that enable plant hormones to regulate growth, development, and stress responses by transmitting and amplifying precise molecular signals. Recent studies suggest that NPs can alleviate stress-induced damage in plants by modulating phytohormone signaling pathways. However, the complex mechanisms underlying the interactions between NPs and phytohormone biosynthesis remain largely unexplored. This review offers a comprehensive overview of nanoparticle synthesis methods, types, and characterization techniques, with particular emphasis on their potential for mitigating both abiotic and biotic stresses. In addition, the article explores the role of NPs in plant pathology, particularly in disease detection and management. It also highlights emerging evidence on the impact of NPs on phytohormone signaling pathways, which are crucial for improving plant resilience and productivity in stress-prone environments. Thus, nanotechnology holds considerable promise for alleviating stress-related challenges and improving crop yields. A deeper understanding of NP–phytohormone interactions is crucial for developing safe and effective nanotechnological strategies to advance sustainable agricultureItem Relative abundance, geographical distribution, and utilization of the edible wild black plum (Vitex doniana) in Uganda(Springer Nature, 2025-08-04) Caku, Jimmy; Kesawat, Mahipal S.; Ddamulira, Gabriel; Masika, Fred BwayoWild edible plants play a crucial role in food security, biodiversity conservation, and sustaining rural livelihoods. Vitex doniana, though widely distributed, remains an underutilized species with significant ecological, economic, and medicinal value. Despite its adaptability across diverse ecosystems, its population in Uganda faces increasing threats from human activities. In addition, the lack of comprehensive data on its abundance and distribution hampers conservation efforts, posing a risk to the plant’s genetic diversity. Ecological and ethnobotanical surveys were conducted in Uganda, Koboko district, to assess the abundance, utilization, and distribution of V. doniana. A total of six line transects and 18 quadrats (three alternating quadrats (50 m × 100 m) with 25 m spacing between quadrats per line transect) were used for data collection. A pre-tested questionnaire was used to collect data on the utilisation of V. doniana from 144 respondents. Data were analysed using descriptive statistics and Chi-square tests in SPSS. Results indicated a higher relative abundance of young regenerating trees (74.0%) than mature trees (26.0%). The distribution of V. doniana across different land-use types showed a statistically significant variation (χ² = 7.17, df = 2, p = 0.028). The local community utilizes the tree for fruit harvesting, firewood, charcoal production, and construction purposes. To ensure the sustainable use of V. doniana, community by-laws, awareness, controlled harvesting, and agroforestry practices should be embraced.Item High-throughput sequencing analysis reveals Moroccan Watermelon Mosaic Virus and Tobacco Streak Virus isolates infecting pumpkins in Uganda(CABI Agriculture and Bioscience, 2025-08-01) Masika, Fred Bwayo; Tugume, Arthur K.; Kesawat, Mahipal S.; Shimelis, Hussein; Ddamulira, Gabriel; Athman, Shahasi Y.; Ipulet, Perpetua; Alicai, TitusPumpkin (Cucurbita pepo L.) is a globally cultivated, economically significant cucurbit species, yet viral diseases pose a major threat to its yield and quality, especially in key production areas such as Uganda. To investigate and document viruses affecting pumpkins in Uganda, we assessed the sub-regional severity of virus-like diseases and identified pumpkin-infecting viruses using RNA sequencing. A total of 75 pumpkin leaf samples displaying typical viral symptoms were collected from 66 fields across Uganda. These samples were then pooled into five bulk groups, each consisting of 15 different plant leaves. Our analysis identified two viruses and detected six viruses, which were, however, not confirmed by another method. The two identified viruses were Moroccan Watermelon Mosaic Virus (MWMV) and Tobacco Streak Virus (TSV). This is the first report of MWMV and TSV infecting pumpkins in Uganda. The virus-like disease symptoms exhibited variations in sub-regional severity and incidence. These findings highlight the current viral diversity in pumpkins in Uganda, providing critical information for developing integrated disease management strategies to enhance crop yield and productivity.Item First report of Moroccan watermelon mosaic virus and other viruses infecting watermelon (Citrullus lanatus) in Uganda(New Disease Report, 2025-05-15) Masika, Fred Bwayo; Mahipal, S. K.; Alicai, T.; Shimelis, H.; Ddamulira, G.; Athman, S. Y.; Ipulet, P.; Osingada, F.; Salman, F. A.; Tugume, A. K.This study reports the first detection of Moroccan watermelon mosaic virus (MWMV) and multiple other viruses infecting watermelon (Citrullus lanatus) in Uganda. Using high-throughput sequencing of leaf samples collected from commercial farms across three districts, we identified six viruses, including MWMV, pepo aphid-borne yellows virus (PABYV), Citrullus lanatus cryptic virus, Cucumis melo cryptic virus, Watermelon crinkle leaf-associated virus, and a novel E. coli virus. The complete genome sequences of MWMV and PABYV were obtained, and virus presence was confirmed through RT-PCR. Observations indicated that mixed infections led to more severe symptoms such as mosaic patterns, leaf mottling, and stunting, affecting approximately 30–40% of cultivated plants. These findings underscore the emerging viral challenges in Ugandan watermelon production and emphasize the importance of vigilant disease monitoring and management strategies.