Experience with fertilizer expert systems for balanced fertilizer recommendations

To evaluate soil fertility and to calculate fertilizer recommendations for different soil types and crop rotations, two expert systems were developed and are being used in Belgium and the Northern part of France. The BEMEX expert system (BEMEX, coming from BEMEstingsEXpertsysteem, Dutch for fertilization expert system) calculates field specific fertilizer recommendations for macronutrients and liming recommendations for crop rotations with arable crops and vegetable crops and for grasslands. The N-INDEX method is a field specific advice-system for N-fertilizer recommendation for most arable and vegetable crops. The knowledge base of BEMEX as well as of N-INDEX contains empirical and theoretical knowledge, The required information to run the expert systems consists of measurements of the chemical soil fertility on soil samples on the one hand and of information concerning the parcel and the crop on the other hand. The final output of the expert system is a two-to-five page bulletin, with the results of soil analysis and the fertilizer and liming recommendations. This bulletin is sent to the farmer. Additionally, an impressive database with soil fertility data is gathered annually. As a consequence presentation models such as choroplets, pie charts, etc. are useful tools to describe soil fertility on the basis of numerous soil analyses. Both the personalized advice bulletins and the general presentation models are the interface between the expert and the user of the expert system, which is commonly the farmer himself or extension staff members. BEMEX and N-INDEX are useful tools for operational decision support on the subject of liming and fertilization.status: publishe

Staphylococcus aureus nasal carriage among healthcare workers in Kisangani, the Democratic Republic of the Congo

Methicillin-resistant Staphylococcus aureus (MRSA) is a global health concern, but there are few data from Central Africa. The objective of our study was to characterise S. aureus colonisation isolates from healthcare-exposed professionals in the Democratic Republic of the Congo (DRC). Healthcare workers and medical students (n = 380) in Kisangani, DRC were screened for S. aureus nasal carriage in a single-centre cross-sectional study in the University Hospital of Kisangani. The isolates were identified and characterised using phenotypic and genotypic methods. The nasal carriage rate of S. aureus was 16.6 % and 10 out of 63 isolates (15.9 %) were MRSA. We found 28 different spa types. Most MRSA isolates belonged to ST8-spa t1476-SCCmec V. The majority of MRSA were multidrug-resistant to non-beta-lactam antibiotics. Overall, 28.5 % of S. aureus carried Panton–Valentine leucocidin (PVL)-encoding genes (all methicillin-sensitive) and 17.5 % carried toxic shock syndrome toxin-1 (TSST-1)-encoding genes. The finding of MRSA carriage among healthcare workers in a setting with limited access to diagnostic microbiology and appropriate therapy calls for improved education on infection control practices and supports the introduction of surveillance programmes.SCOPUS: ar.jinfo:eu-repo/semantics/publishe