Disease suppression of potting mixes amended with composted biowaste

Peat mining destroys valuable nature areas and contributes to the greenhouse effect. This warrants the search for alternatives for peat in potting mixes. Composted biowaste could provide such an alternative. An additional advantage of (partially) replacing peat by compost is the increased disease suppressiveness. In this study, nine commercial composted biowastes were tested for disease suppressiveness using the pathosystems Pythium ultimum-cucumber, Phytophthora cinnamomi-lupin and Rhizoctonia solani-carrot. Increased disease suppression was found in compost-amended potting mixes for all three pathosystems. The level of disease suppression ranged from slight stimulation of disease to strong suppression. Suppressiveness against one disease was not well correlated with that against the other diseases. The CO2 production, a measure of general microbial activity, was the parameter most strongly correlated with the level of disease suppression. Wetsieving the biowaste with tap water over a 4-mm sieve prior to composting yielded a compost with an 2.4-fold increase in organic matter and a twofold decrease in EC and Cl--concentration of the compost. The latter reductions allow for an increase of the amount of peat that can be replaced by compost. A linear relation was found between the amount of compost added to the potting mix and the level of disease suppression indicating the potential for increasing disease suppressiveness of potting mixes by replacing peat by high-quality composted biowastes

De cementrustieke brug van kasteel De Haar, een gemiste kans

No doubt the intention was good. However, the result turned out much less favourably. In the year 1996 the cement-rustic bridge at Bochtdijk in the park of De Haar Castle was restored. It had the appearance of a bridge made of tree-trunks, a frequently used technique in the nineteenth century and the beginning of the twentieth century. It looked as if a lorry had bumped into it a very long time ago, and had damaged the right-hand side. However, the iron in the cement may have started to 'work', a frequently occurring problem. The 'restoration' was very rigorous indeed. The bridge itself ended up in a large container, while a building firm was constructing a new bridge in a similar style. An utterly wrong approach, making the bridge completely useless as a bearer of information on a historical building technique. In principle, it also made identification of the workshop that had built this bridge impossible. The starting point of the 'restoration' was the general appearance of the bridge, but evidently the builders were not acquainted with the subtleties of cement-rustic, a nineteenth-century style that had not been documented in detail yet. For the crux is the representation of the 'tree-bark' grains, which is the signature of every cement-rustic builder, called 'rocailleur' in France and Wallonia and 'rotseerder' in Flanders. The plasterer who gave the new bridge its present appearance, though an expert in his trade, could not have known this. But the commissioner should have, or should at least have given instructions for expert research. This was omitted, and that is why the cement-rustic bridge as a historical object was lost to us. It subsequently appeared that the bridge was a product of the firm F.J. Moerkoert from De Bilt. And a long story is attached to this

Target product profiles:leprosy diagnostics

The World Health Organization (WHO) aims to reduce new leprosy cases by 70% by 2030, necessitating advancements in leprosy diagnostics. Here we discuss the development of two WHO's target product profiles for such diagnostics. These profiles define criteria for product use, design, performance, configuration and distribution, with a focus on accessibility and affordability. The first target product profile outlines requirements for tests to confirm diagnosis of leprosy in individuals with clinical signs and symptoms, to guide multidrug treatment initiation. The second target product profile outlines requirements for tests to detect Mycobacterium leprae or M. lepromatosis infection among asymptomatic contacts of leprosy patients, aiding prophylactic interventions and prevention. Statistical modelling was used to assess sensitivity and specificity requirements for these diagnostic tests. The paper highlights challenges in achieving high specificity, given the varying endemicity of M. leprae, and identifying target analytes with robust performance across leprosy phenotypes. We conclude that diagnostics with appropriate product design and performance characteristics are crucial for early detection and preventive intervention, advocating for the transition from leprosy management to prevention.</p

Target product profiles:leprosy diagnostics

The World Health Organization (WHO) aims to reduce new leprosy cases by 70% by 2030, necessitating advancements in leprosy diagnostics. Here we discuss the development of two WHO's target product profiles for such diagnostics. These profiles define criteria for product use, design, performance, configuration and distribution, with a focus on accessibility and affordability. The first target product profile outlines requirements for tests to confirm diagnosis of leprosy in individuals with clinical signs and symptoms, to guide multidrug treatment initiation. The second target product profile outlines requirements for tests to detect Mycobacterium leprae or M. lepromatosis infection among asymptomatic contacts of leprosy patients, aiding prophylactic interventions and prevention. Statistical modelling was used to assess sensitivity and specificity requirements for these diagnostic tests. The paper highlights challenges in achieving high specificity, given the varying endemicity of M. leprae, and identifying target analytes with robust performance across leprosy phenotypes. We conclude that diagnostics with appropriate product design and performance characteristics are crucial for early detection and preventive intervention, advocating for the transition from leprosy management to prevention.</p

The long-term impact of the leprosy post-exposure prophylaxis (Lpep) program on leprosy incidence:a modelling study

Background The Leprosy Post-Exposure Prophylaxis (LPEP) program explored the feasibility and impact of contact tracing and the provision of single dose rifampicin (SDR) to eligible contacts of newly diagnosed leprosy patients in Brazil, India, Indonesia, Myanmar, Nepal, Sri Lanka and Tanzania. As the impact of the programme is difficult to establish in the short term, we apply mathematical modelling to predict its long-term impact on the leprosy incidence. Methodology The individual-based model SIMCOLEP was calibrated and validated to the historic leprosy incidence data in the study areas. For each area, we assessed two scenarios: 1) continua-tion of existing routine activities as in 2014; and 2) routine activities combined with LPEP starting in 2015. The number of contacts per index patient screened varied from 1 to 36 between areas. Projections were made until 2040. Principal findings In all areas, the LPEP program increased the number of detected cases in the first year(s) of the programme as compared to the routine programme, followed by a faster reduction after-wards with increasing benefit over time. LPEP could accelerate the reduction of the leprosy incidence by up to six years as compared to the routine programme. The impact of LPEP varied by area due to differences in the number of contacts per index patient included and differences in leprosy epidemiology and routine control programme. Conclusions The LPEP program contributes significantly to the reduction of the leprosy incidence and could potentially accelerate the interruption of transmission. It would be advisable to include contact tracing/screening and SDR in routine leprosy programmes.</p

An Overview of Phytosanitary Risk Aspects of Composting by Organic Farmers

Usage of compost in agriculture always brings about the risk of introducing plant pathogens. By proper composting, resulting in high temperatures during the thermophilic phase, compost can be applied safely. Organic farmers often prefer to compost organic residues themselves. The advantage of such an approach is that no material of foreign origin is introduced, but a drawback is the smaller scale of composting, which brings about greater phytosanitary risks. These risks can be dealt with by increasing the composting duration and by proper turning of the compost heap. If only organic residues from farms are composted, this usually results in low-quality composts because of the low lignin contents. Therefore, addition of materials that are high in lignin, such as wood chips, is advisable. In conclusion, on-farm composting is well possible from a phytosanitary point of view, but the farmer has to be aware of the factors that affect the phytosanitation of organic waste and the quality of the compost