No-tillage and biochar amendment are widely regarded as effective strategies to mitigate greenhouse gas (GHG) emissions. However, the combined effects of no-tillage, biochar and nitrogen (N) fertilizer application on rice yield and GHG emissions remain scarcely investigated. We conducted a two-year field experiment in central Cote d'Ivoire to assess how biochar and N-fertilizer application under no-tillage influences methane (CH4) and nitrous oxide (N2O) emissions, global warming potential (GWP), GHG intensity (GHGI), and rainfed lowland rice yield. The experiment included three N-fertilizer rates (0, 60, and 120 kg N ha-1) combined with two biochar rates (3, and 6 t ha-1) under no-tillage, alongside two additional treatments; N-only fertilizer (120 kg N ha-1) under no-tillage, and under manual tillage (conventional practice). No-tillage combined with biochar and N-fertilizer increased N2O emissions (9-96 %), but reduced CH4 emissions (13-21 %) and increased rice yields (4-10 %) compared to conventional practice. This trade-off led to significant reductions in GWP (10-20 %) and GHGI (15-18) by no-tillage combined with biochar and N-fertilizer relative to conventional practice. Co-application of 6 t ha-1 biochar with 60 kg N ha-1 under no-tillage produced the highest partial N productivity. Conversely, applying N-fertilizer alone under no-tillage resulted in 43 % higher CH4 emission than conventional practice. Across treatments, CH4 emissions contributed 95 % of the total GWP, and soil moisture emerged as the main driver of CH4 fluxes. These findings suggest that applying biochar and N-fertilizer under no-tillage represents a promising pathway to enhance rainfed lowland rice yield and reduce GHG emissions.
ABSTRACT Introduction Genital chlamydia is one of the most common sexually transmitted infections (STIs) among young people aged 15–24 years old and may lead to serious complications in women, men, and newborns. This study aimed to evaluate the effectiveness of a five-day interactive hybrid educational workshop on knowledge, attitudes, and practices (KAP) related to genital chlamydia in Bamako, Mali. Materiel and Methods A descriptive pre-test/post-test study was conducted in 2025 among 174 young participants aged 15–24 years old. Data were collected using a standardized questionnaire assessing KAP related to genital chlamydia and STIs. Proportions before and after the intervention were compared using the chi-square (χ²) test or Fisher’s exact test, with a significance level set at α = 0.05. Results Overall knowledge of STIs showed a slight improvement after the intervention, with the “poor knowledge” category disappearing at post-test. The proportion of participants able to identify at least three modes of transmission of genital chlamydia increased from 41.7% to 50.0%. Improvements were also observed in the identification of symptoms and complications, with a statistically significant increase in knowledge of male complications (p = 0.045 for at least one complication; p = 0.003 for at least two complications). Information sharing about genital chlamydia with partners remained limited (8.3% vs. 7.4%), whereas discussion of STI status between partners increased (62.5% to 72.2%). Preventive practices improved modestly, including consistent condom use (62.5% to 66.7%), prompt health-care seeking (95.0% to 96.3%), and acceptability of on-demand STI screening (70.8% to 83.3%). Conclusion The hybrid educational workshop contributed to improved knowledge and several positive attitudes toward genital chlamydia, particularly regarding communication about STI status and acceptability of screening. However, persistent stigma and limited information sharing with sexual partners underscore the need for sustained and repeated educational interventions targeting young people for chlamydia prevention and control.
Background The global burden of dementia is escalating due to the aging population. While amyloid and tau biomarkers are central to Alzheimer's disease (AD) pathology, their causal roles across dementia subtypes are not fully understood. Objective This study investigated the causal effects of cerebrospinal fluid (CSF) and plasma amyloid, tau, and hyperphosphorylated tau (p-tau) proteins on dementia [AD, frontotemporal dementia (FTD), and vascular dementia (VaD)] risk. Methods In this study, we conducted a two-sample Mendelian randomization analysis using genome-wide association study (GWAS) summary statistics. The AD, CSF, and plasma amyloid, tau, and p-tau data were obtained from the GWAS catalog, while those for FTD and VaD were obtained from the FINNGEN database. The inverse variance weighting method, combined with sensitivity analysis, was used to obtain the estimates. Results CSF p-tau in individuals with abnormal amyloid and APOE ε4 non-carriers was positively associated with AD risk [IVW: OR = 1.07, 95% CI = 1.01–1.13, p = 0.016; OR = 1.08, 95% CI = 1.02–1.14, p = 0.014, respectively]. CSF p-tau was also associated with VaD (IVW: OR = 1.11, 95% CI = 1.03–1.20, p = 0.008). Plasma Aβ 1−42 reduced the odds of FTD (IVW: OR = 0.83, 95% CI = 0.70–0.98, p = 0.03), whereas CSF Aβ 42 increased FTD risk (weighted median: OR = 1.58, 95% CI = 1.02–2.44, p = 0.041). Conclusions The findings support the causal roles of tau and amyloid across dementia subtypes, reinforcing the value of biomarker-driven prevention and therapeutic strategies.
Introduction Mansonellosis is one of the most neglected tropical diseases. It is caused by filarial nematodes of the genus Mansonella, the different species of which are Mansonella perstans, M. ozzardi and M. streptocerca. M. perstans is the most abundant species in Mali. This study aimed to explore the feasibility of opportunistic molecular surveillance of Mansonella sp. using qPCR on archived malaria rapid diagnostic tests (RDTs) and to document this filariasis nationwide distribution among patients tested for malaria in health facilities in Mali. Methods Between June and December 2021, a total of 1,496 archived malaria RDTs were randomly selected from 41 sites distributed across Mali's nine administrative regions. Thirty positive RDTs (excluding Menaka and Kidal, where all positive tests were included) and 150 negative RDTs (excluding Menaka, where all negative tests were included) were selected for further quantitative polymerase chain reaction (qPCR) analyses in each region. DNA was extracted from the nitrocellulose strips of the RDTs. All samples were screened using real-time PCR targeting all filarial parasites. Positive samples were tested using a M. perstans-specific qPCR, and the internal transcribed spacer 1 of the rRNA gene sequence was analysed. Results M. perstans DNA was detected in 2 (1.1%) of the 180 samples from the Koulikoro region. All 1316 samples from the 8 other regions of Mali were negative. Conclusions M. perstans DNA was detected in 2 of 1,496 archived malaria RDTs (0.1%), both collected in the Koulikoro region. These findings document the presence of M. perstans among patients attending health facilities and tested for malaria using RDTs but should not be interpreted as population-based prevalence estimates.
Abstract Background Chronic kidney disease and heart failure frequently coexist, and observational studies suggest a correlation between CKD and heart failure risk. However, these associations are susceptible to confounding and reverse causation. Mendelian randomisation (MR) offers an approach to strengthen causal inference, yet evidence from African ancestry populations remains scarce even though their greater genetic diversity and shorter linkage disequilibrium structure which may enhance instrument resolution and causal inference. Purpose To investigate the bidirectional causal relationship between kidney function and heart failure using African ancestry–specific genome-wide association study (GWAS) data. Methods We performed a bidirectional two-sample MR analysis restricted to African ancestry GWAS. Genetic instruments for estimated glomerular filtration rate (eGFR) were obtained from the African ancestry subset of the Kidney multiome-based genetic scorecard study1 (N=67,943). Heart failure summary statistics were derived from the African ancestry subset of the Global Biobank Meta-analysis Initiative2. Forward (eGFR → heart failure) and reverse (heart failure → eGFR) analyses were conducted using ancestry-matched linkage disequilibrium clumping. Instrument strength was assessed using F-statistics and variance explained (R²). Primary causal estimates were obtained using inverse-variance weighted (IVW) random-effects models, with weighted median and weighted mode estimators as sensitivity analyses. Horizontal pleiotropy, heterogeneity, and directionality were formally evaluated. To contextualise precision, we calculated the minimum detectable effect (MDE) at 80% power and α=0.05 using the observed R² and effective outcome sample size. Results eGFR instruments were strong (minimum F=30.5; median 35.5) but explained 0.37% of variance (R²=0.0037). Median effective heart failure sample size was 4,142. Forward analysis (eGFR → heart failure) showed no association (IVW OR 0.83, 95% CI 0.17–4.20; p=0.83; 5 SNPs), with consistent sensitivity analyses and no evidence of directional pleiotropy. Power calculations indicated detection of only large effects (minimum detectable OR ≈1.9–2.0). Reverse analysis (heart failure → eGFR) showed no significant association (IVW β −0.018, SE 0.011; p=0.10; 12 SNPs). Steiger filtering supported directionality. Conclusion In this African ancestry–specific bidirectional MR study, we observed no statistically significant evidence of causal association between kidney function and heart failure in either direction. However, despite strong instruments, limited variance explained, and a modest effective sample size, restricted statistical power to detect only large effects. These findings demonstrate the feasibility of ancestry-matched MR in African populations while highlighting the need for larger and more comprehensive African ancestry GWAS to robustly evaluate cardio-renal causal relationships.Figure 1.Mendelian randomisation frameworkFigure 2.Forest plot of MR estimates
