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Abstract In Sub-Saharan countries, cooking is usually done at a domestic scale using rudimentary stoves with wood or charcoal as combustibles. To improve the cooking behavior and reduce the deforestation, an improved pellet cookstove was conceptualized with guiding ideas in mind such as simplicity, robustness and ability to burn pellets built with local wood residues under a natural draught. Combustion and water ebullition tests were performed with two configurations of the upper part of the cookstove: thick steel plate or ring, and with standardized EN+ pellets as combustible. The main pollutant gases (CO, CO2 and NOx), together with O2, were continuously measured at different positions of the cookstove during a water ebullition test with the ring configuration. The levels measured above the pot were lower than the thresholds currently proposed by the World Health Organization. Simple and phenomenological thermal models were proposed to simulate the plate, or ring, and water temperatures during the combustion or water ebullition tests and to determine the intrinsic convection coefficients. The maximal relative differences between the experimental and simulated temperatures were computed between 7 and 21%. The stove power was evaluated at 4336 ± 23 W. The cookstove yield for the water ebullition test with the ring configuration was computed equal to 12.3 ± 0.1%, slightly lower than that of cookstoves previously analyzed in the literature.

In the course of global climate change, Central Europe is experiencing more frequent and prolonged periods of drought. The drought years 2018 and 2019 affected European beeches (Fagus sylvatica L.) differently: even in the same stand, drought-damaged trees neighboured healthy trees, suggesting that the genotype rather than the environment was responsible for this conspicuous pattern. We used this natural experiment to study the genomic basis of drought resistance with Pool-GWAS. Contrasting the extreme phenotypes identified 106 significantly associated single-nucleotide polymorphisms (SNPs) throughout the genome. Most annotated genes with associated SNPs (>70%) were previously implicated in the drought reaction of plants. Non-synonymous substitutions led either to a functional amino acid exchange or premature termination. A non-parametric machine learning approach on 98 validation samples yielded 20 informative loci which allowed an 88% prediction probability of the drought phenotype. Drought resistance in European beech is a moderately polygenic trait that should respond well to natural selection, selective management, and breeding.

Three types of biomasses (miscanthus, spruce, and a mixture of different woodchips species) were tested as low-cost adsorption media for an industrial agro-industrial effluent, typically a vinasse. Influences of effluent dilution, working temperature, and time duration were studied. Kinetic modelling studies of adsorption were proposed. Ratios of adsorption at ambient temperature and without dilution expressed in g of dry vinasse per g of dry biomass were 1.0, 0.85, and 0.65 for miscanthus, woodchips mixture, and spruce, respectively. An increase of the temperature from 10 °C to 50 °C led to a decrease of the vinasse viscosity and favored its penetration in the biomasses. Maximal adsorbance of dry matter of vinasse was obtained at 50 °C for a vinasse viscosity of 20 mPas. Whatever the experimental conditions required during adsorption processes, miscanthus showed the best affinity for the vinasse. Pseudo-second order and intra-particle diffusion model well described the adsorption process. This study indicates that conventional biomasses could be used as natural low-cost adsorbent for by-products such as vinasse.

Abstract This work presents a study of a magnesium/air combustion process in the context of innovative zero carbon dioxide (CO 2) energy carriers for reducing global warming effects. In order to analyze more deeply the confined combustion of magnesium under fluctuating overpressure conditions (0 to 24 hPa) and the generated gaseous by-products, magnesium/air flames have been realized in a combustion chamber with a conical bluff-body as flame holder and different contraction ratios diaphragms at the exit duct. Sieved magnesium samples with two size-fractions were tested: 20–50 µm and 50–70 µm. The gaseous emissions of nitrogen oxides (NO x) and dioxygen (O 2) were analyzed with on-line infrared, ultraviolet and paramagnetic analyzers. A flame pulsating behavior was clearly observed from light emission intensity (monitored by a photodiode) and pressure fluctuations (monitored by a pressure sensor); the frequencies obtained ranged between 3 and 10 Hz. The frequency of the pulsation exhibited strong dependence on the geometric configuration of the chamber: a contraction diaphragm divided by two the frequency level of the fluctuations in the studied range of maximum overpressure. Such fluctuations may probably be the consequence of periodic perturbations of the recirculation zone behind the bluff-body. These periodic perturbations are themselves caused by strong periodic overpressure variations due to stiff contraction downstream responding to gas velocity fluctuations. This feed-back-loop mechanism was considered in this study. NO x emissions produced through the thermal pathway were analyzed for equivalence ratios ranging from 0.29 to 1. The representation of NO x versus equivalence ratio exhibited a parabolic shape with a maximum for an equivalence ratio of 0.4. Moreover, NO x emissions of this metal combustor have shown a similar order of magnitude than current internal combustion engines. [ABSTRACT FROM AUTHOR]

Accurate estimates of genome sizes are important parameters for both theoretical and practical biodiversity genomics. Here we present a fast, easy-to-implement and accurate method to estimate genome size from the number of bases sequenced and the mean sequencing depth. To estimate the latter, we take advantage of the fact that an accurate estimation of the Poisson distribution parameter lambda is possible from truncated data, restricted to the part of the sequencing depth distribution representing the true underlying distribution. With simulations we show that reasonable genome size estimates can be gained even from low-coverage (10×), highly discontinuous genome drafts. Comparison of estimates from a wide range of taxa and sequencing strategies with flow cytometry estimates of the same individuals showed a very good fit and suggested that both methods yield comparable, interchangeable results., (© 2021 The Authors. Molecular Ecology Resources published by John Wiley & Sons Ltd.)

In the course of global climate change, Central Europe is experiencing more frequent and prolonged periods of drought. The drought years 2018 and 2019 affected European beeches ( Fagus sylvatica L.) differently: even in the same stand, drought-damaged trees neighboured healthy trees, suggesting that the genotype rather than the environment was responsible for this conspicuous pattern. We used this natural experiment to study the genomic basis of drought resistance with Pool-GWAS. Contrasting the extreme phenotypes identified 106 significantly associated single-nucleotide polymorphisms (SNPs) throughout the genome. Most annotated genes with associated SNPs (>70%) were previously implicated in the drought reaction of plants. Non-synonymous substitutions led either to a functional amino acid exchange or premature termination. An SNP assay with 70 loci allowed predicting drought phenotype in 98.6% of a validation sample of 92 trees. Drought resistance in European beech is a moderately polygenic trait that should respond well to natural selection, selective management, and breeding., Competing Interests: MP, FR, AK, PS, CC, SG, BC, SR, NB, KM, BM, MB, MT, BF No competing interests declared, (© 2021, Pfenninger et al.)