Crop and varietal diversification are essential for African smallholder farmers to adapt to the complex and unprecedented challenges posed by climate change. Although African genebanks maintain seed collections of numerous crops, with thousands of varieties collected from their countries' farmers, the direct use of these collections by farmers is very limited. Five African national genebanks therefore explored ways to strengthen farmers' access to and use of these collections through a longer-term collaborative process. The genebanks and their partners engaged with 'Germplasm User Groups' as a basis for facilitating sustained joint learning with farmers for use of conserved germplasm. The structure of these groups and the methods they used for identifying and testing germplasm accessions, although differing by country context, all enabled a diversity of farmers to learn about a wide range of germplasm under relevant field conditions. The large number of accessions that farmers selected, their diverse advantages and the requests by numerous farmer groups to continue exploring additional crops and varieties indicated the usefulness of these approaches. These experiences revealed the feasibility and unique roles and opportunities for national genebanks to facilitate farmers' direct use of the diversity conserved in their crop collections. National genebanks thus have unique responsibilities for adapting their operating procedures and partnering with research and development practitioners to facilitate farmers' discovery and use of their conserved crop diversity.
Wastewater-based epidemiology (WBE) is a powerful analytical tool for determining community-level exposure to legal and illicit chemicals by analysing parent materials and human metabolites in sewage influent. In this work, liquid chromatography-tandem mass spectrometry (LC-MS/MS) was utilised to quantify seven drug biomarkers in weekly influent samples collected over a 16-week period (February-May) from a major wastewater treatment facility in Nairobi, Kenya. The target analytes were amphetamine (AMP), methamphetamine marker (MAMP), benzoylecgonine (BE), cocaine (COC), morphine (MOR), codeine (COD), and 11-nor-9-carboxy-tetrahydrocannabinol (THCCOOH). Concentrations were measured in the ng L-1 range and analysed using descriptive statistics and short-term temporal trends. BE was regularly found at moderate levels (mean 15.3 ng L-1), while AMP and THC-COOH had the highest mean concentrations (31.9 and 19.8 ng L-1, respectively). The pooled standard deviations (0.46-2.72 ng L-1) showed low week-to-week variability. Linear regression indicated mostly stable temporal patterns, with very small positive trends in AMP and MAMP. Overall, the findings illustrate the analytical feasibility of LC-MS/MS-based WBE in an urban African setting, taking into account population normalisation, influent flow variability, analytical recovery, and in-sewer transformation.
This paper makes the case for the regional scale as a space for resilient, sustainable food system transformation. Drawing from the literature and using the example of the Food Learning and Growing (FLOW) Partnership, we propose a hybrid methodology to explore, monitor and track enablers, barriers and changes over time. FLOW includes ten food regions where we are tracking various dimensions of transformation. The regional food systems capacities framework introduced herein is the theoretical basis for our work and frames our research. This framework underpins our research approach that includes developing multi-actor groups to guide our research and using collective visioning and impact pathways to map changes. Impact pathway maps help identify indicators to monitor and track changes and follow the paths to transformation. The indicators are brought to life through stories of change that will be shared across the research project to inform and catalyze ideas between regions. The stories will also be shared outside the FLOW partnership to inform and inspire others who seek to transform their food systems. Our goal is to understand the socio-ecological, economic, human and governance capacities that facilitate transformation from industrial food systems to ones that realize fair livelihoods, the right to food, food security, and ecological integrity.
Evaluation of nuclear masses is important not only for studies of nuclear structure but also for the synthesis of superheavy nuclei (SHN), fission processes, and astrophysical studies. However, experimental data in the superheavy region are scarce. Accurate theoretical mass models therefore play a crucial role in extrapolating nuclear masses not only beyond Z=118 but also toward the neutron and proton drip-line regions. In this study, a modified Bethe-Weizsäcker (MBW) binding energy formula for the superheavy region is proposed. The formula is based on a new description of a nuclear structure consisting of two regions: a dense nuclear core, assumed to contain equal number of protons and neutrons (2Z), and a nuclear surface composed of excess neutrons (N-Z). The surface and the Coulomb terms have been parameterized to account for the two regions, in addition to incorporating a modified shell-correction term and a deformation term. The calculated binding energies for 188 nuclei with , obtained using the modified Bethe-Weizsäcker (MBW) formula, are compared with experimental data from the AME 2020 mass table, predictions from FRDM 2012, and values obtained from the original Bethe-Weizsäcker formula. The modified formula yields a root-mean-square (RMS) deviation of 3.5 keV per nucleon, demonstrating excellent agreement with the experimental data. The proposed MBW formula is therefore well suited for extrapolating nuclear masses of superheavy nuclei that are likely to exist in the predicted island of stability.
The influence of precursor solution volume on the characteristics of containing iron-doped titanium dioxide (Fe:TiO 2 ) thin films was examined in this work. The coatings were prepared on transparent substrates by the spin-coating method using precursor volumes between 0.5 and 2.5 mL. Following deposition, the coatings were heat treated at 450°C and analyzed using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and ultraviolet-visible (UV-Vis) spectroscopy. XRD analysis revealed the presence of both rutile and anatase crystalline phases, evidenced by reflections near 27.4° and 49° corresponding to the (110) and (200) planes, respectively. Variations in precursor volume affected the crystallographic properties of the films, with the sample prepared using 1.0 mL exhibiting the largest crystallite size and sharper diffraction peaks, suggesting improved crystal growth. Increasing the precursor volume beyond this value resulted in peak broadening, which may be associated with greater lattice imperfections and strain within the films. The FTIR results identified characteristic vibrational bands assigned to Ti-O-Ti and Ti-O-Fe linkages, confirming the incorporation of iron species into the TiO 2 network. Optical characterization showed that increasing precursor volume shifted the absorption threshold toward longer wavelengths and reduced the optical band gap. This behavior can be ascribed to the creation of defect-induced energy states and oxygen-vacancy states within the material. Overall, the findings demonstrate that precursor solution volume significantly affects both the crystallographic and photonic performance of Fe:TiO 2 coatings, with the 1.0 mL sample providing the most favorable combination of crystallinity and film quality.
