Most research on biochar has focused either on the mechanistic or the biophysical aspects, and there has been relatively little research into the social applicability and acceptance of biochar as a soil enhancer in agriculture. However, whether to adopt biochar in their practice is ultimately the farmers’ decision, and their willingness to do so is crucial. Here, we show the producer’s perspective on adopting biochar, using Polish farmers as a case study. Poland is an interesting case study because biochar has only recently attracted the attention of researchers, entrepreneurs, and other stakeholders there. We performed standardized, semi-structured interviews with 161 Polish farmers to evaluate the socioeconomic potential of biochar application in practice. We found that 27% of the respondents claimed to be familiar with biochar. The respondents with a technical, non-agricultural level of education were most familiar with the term ‘biochar’ (36%), followed by the group of respondents with a higher-level agricultural education (31%). It was surprising that among the latter respondents, the majority (69%) did not know the term ‘biochar’, either in the context used for this study or in any other context. Twenty percent of the respondents expressed an interest in using biochar, while 43% were not willing to adopt it in their agricultural practice (37% ‘did not know yet’). If a farmer was familiar with the concept of sustainable agriculture, the probability of familiarity with biochar increased by 16% (p < 0.05). In addition, farmers interested in using biochar indicated that sustainable agriculture might improve the financial situation of their farms (52%). The perceived benefits of biochar that drive the willingness to adopt it included improved soil quality and increased income due to increased yields, while the constraints on its adoption were associated mainly with high costs. Our results also point to the necessity of information flow as well as engaging farmers in participatory research to adjust the research to their needs. Furthermore, our results highlight the importance of transparency with the farmers and appropriate dissemination and presentation of both the positive and the negative aspects of biochar adoption. We urge those studying biochar to engage in more interdisciplinary research and to go beyond laboratory and field research. Many innovations, even those that work, will not be adopted if socioeconomic considerations are not incorporated into the research.

Experimental tests regarding the M-346 aircraft model made via 3D printing were carried out in order to obtain numerical data and characteristics in the form of graphs of basic aerodynamic forces and coefficients. The tests were carried out for the left side of the airframe model in a clean configuration, without additional suspension equipment; the flight control surfaces and the aerodynamic brake were in neutral positions. Based on the scan of the base model in 1:48 scale using a Nikon Model Maker MMDx laser scanning head, followed by the generation and optimization of some of the airframe elements in SolidWorks software, a test model ready for printing was prepared. Using the MakerBot Print program, the printing parameters were set, and the process itself was completed using a MakerBot Replicator Z18 3D printer. The next step was manual treatment in order to remove the material excess from the melted thermoplastic material, join the elements and appropriately polish the surface of the tested model in order to obtain the desired quality. The test was carried out using a Gunt HM 170 wind tunnel for fixed airflow velocities at variable angles of attack. On this basis, the numerical values of lift force, Pz, and drag force, Px, were obtained; then, the lift force indices, Cz, and drag force indices, Cx, were computed for the steady states, which were for angle α from −12 to 16°. The use of 3D printing contributed to the generation of geometry, which, for research purposes, was scaled down in order to fully use the available measurement space of the wind tunnel. The final stage of the work was to compare the obtained curves of particular characteristics with the literature data.

The experiment was conducted to evaluate the effect of yeast culture ( Saccharomyces cerevisiae ) supplementation on ruminal fermentation in 20 Holstein dairy cows divided into control and experimental groups, each group of 10 cows. The animals received a diet based on maize silage (19 kg), alfalfa silage (15 kg), meadow hay (1.5 kg), extracted rapeseed meal (1 kg) and concentrate mixture (9.5 kg). The diets were fed as a total mixed ration. The supplement of yeast culture Levucell ^® SC 20 ( Saccharomyces cerevisiae – CNCM I-1077; min. content 2 × 10 ¹⁰ CFU·g ^-1 ) was added to the concentrate mixture in the ration fed to the experimental group of animals. The addition of yeast culture significantly ( P < 0.01) increased ruminal pH but had no positive effects on the increased production of volatile fatty acids. The supplementation of yeast culture significantly ( P < 0.01) increased numbers of protozoa in the rumen of dairy cows of the experimental group (361.3 ± 18.315) compared to the control group (308.3 ± 37.505). The addition of yeast culture significantly ( P < 0.01) increased concentration of serum glucose, calcium, phosphorus, copper, zinc, magnesium and AST ( P < 0.05). As compared to the control group (4.948 ± 0.0384 mmol·l ^-1 ), the level of urea in the blood serum was significantly decreased ( P < 0.01) in the experimental group of cows. Our results show that the supplementation of Saccharomyces cerevisiae culture at recommended doses enhances ruminal fermentation which may have a positive effect on milk production and health status of Holstein dairy cows.

An important requirement in the grain industry is to obtain fast information on the quality of purchased and stored grain. Therefore, it is of great importance to search for innovative solutions aimed at the monitoring and fast assessment of quality parameters of stored wheat The results of the evaluation of total protein, water and gluten content by means of near infrared spectrometry are presented in the paper. Multiple linear regression analysis (MLR) and neural modeling were used to analyze the obtained results. The results obtained show no significant changes in total protein (13.13 ± 0.15), water (10.63 ± 0.16) or gluten (30.56 ± 0.54) content during storage. On the basis of the collected data, a model artificial neural network (ANN) MLP 52-6-3 was created, which, with the use of four independent features, allows us to determine changes in the content of water, protein and gluten in stored wheat. The chosen network returned good error values: learning, below 0.001; testing, 0.015; and validation, 0.008. The obtained results and their interpretation are an important element in the warehouse industry. The information obtained in this way about the state of the quality of stored grain will allow for a fast reaction in case of the threat of lowering the quality parameters of the stored grain.

The paper presents an innovative method based on vision techniques for rapid assessment of contamination in the mass of stored maize grain. The research was carried out in a selected grain warehouse in the Opolskie Province. Maize grain was used in the studies, which was subjected to tests based on computer image analysis. To assess the state of maize grain contamination, a proprietary computer application based on the RGB model was used.