We talk to Prof. Bożena Kamińska-Kaczmarek from the Nencki Institute of Experimental Biology about treating cancer, obvious and impossible discoveries, and academic courage and strength.

We talk to Prof. Jerzy Jarzębski from the Jagiellonian University in Kraków and the Eastern Europe State University in Przemyśl about Stanisław Lem and the future he foresaw, his cautionary tales and whether he is still an author often misunderstood.

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics.

Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points.

Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.

Robotics specialists observe nature carefully and try to recreate the complex motions performed by people and animals with ease. Locomotion and the ability to manipulate flexible objects are especially challenging, but progress is being made.

“People generally associate my name with the first ever heart transplant in Poland. But I know that if I hadn’t tried to do it, then four, maybe five years later someone else would have. What I am sure of, however, is that no one else in Poland would have started working on developing an artificial heart. Had I not fought to create this device, a few hundred people would not be alive today because we wouldn’t have had ventricular assist devices which saved their lives and wellbeing.”

– Zbigniew Religa,

famous Polish cardiac surgeon

Dr. Maciej Maryl, Head of the Digital Humanities Center and Deputy Director at the Institute of Literary Research, Polish Academy of Sciences, talks about the table where innovations are born, the limits of literariness, and Polish humanities projects that can conquer the world.

Prof. Hanna Bogucka, head of the Department of Wireless Communications at the Poznań University of Technology, discusses unnecessary inhibitions, the usefulness of microphones, and the links between people and technology.

We talk to Prof. Małgorzata Kossowska from the Institute of Psychology at the Jagiellonian University about whether women are appreciated, the significance of openness and tolerance, and what makes a terrorist.

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics.

Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points.

Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.

Prof. Przemysław Śleszyński from the PAS Institute of Geography and Spatial Organization in Warsaw (author of an extensive study of 122 medium-sized Polish cities) explains why Poland’s midsize cities are facing depopulation.

The story of the Polish nuclear research facility in Świerk has always been closely linked to the political and social changes underway in the country – as Ewa, Anna, Maryla, Agata, Maria, and Wanda have all borne witness.

Some works are smarter than their authors.

What can parasites do? According to Kathleen McAuliffe’s book This is Your Brain on Parasites, they can affect human thinking and behavior, and thus change us into obedient machines.

Mateusz Banaszkiewicz, from the SWPS University of Social Sciences and Humanities in Warsaw, talks about the effects of thinking and acting automatically, and how to fight destructive habits.

We talk to Prof. Piotr Homola from the Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences in Kraków, about his search for cosmic ray ensembles.

People are trusting scientific expertise less and less, and increasingly rely on what can euphemistically referred to as the “wisdom of the crowds.” What are the effects of this, and what might be done about it?

Obtaining a pure product by mixing together raw materials, so as to carry out a chemical reaction at high selectivity, is a difficult part of manufacturing chemical products. How can we test reactors and mixers to ensure the efficient use of energy?

We talk to Professor Andrzej Trautman, Full Member of the Polish Academy of Sciences and Emeritus Professor at the University of Warsaw, about the consequences of the general theory of relativity, the theoretical foundations of gravitational waves and the difficulties in proving their existence.

The aim of the study was to compare two grouping methods for regionalisation of watersheds, which are similar in respect of low flow and chosen catchments parameters (physiographic and meteorological). In the study, a residual pattern approach and cluster analysis, i.e. Ward’s method, were used. The analysis was conducted for specific low flow discharge q95 (dm3∙s–1∙km–2). In the analysis, 50 catchments, located in the area of the upper and central Vistula River basin, were taken. Daily flows used in the study were monitored from 1976 to 2016. Based on the residual pattern approach (RPA) method, the analysed catchments were classified into two groups, while using the cluster analysis method (Ward’s method) – into five. The predictive performance of the complete regional regression model checked by cross-validation R2cv was 47% and RMSEcv = 0.69 dm3∙s–1∙km–2. The cross validation procedure for the cluster analysis gives a predictive performance equal to 33% and RMSEcv = 0.81 dm3∙s–1∙km–2. Comparing both methods, based on the cross-validated coefficient of determination (R2cv), it was found that the residual pattern approach had a better fit between predicted and observed values. The analysis also showed, that in case of both methods, an overestimation of specific low flow discharge q95 was observed. For the cross-validation method and the RPA method, the PBIAS was –10%. A slightly higher value was obtained for the cross-validation method and models obtained using cluster analysis for which the PBIAS was –13.8%.

The study aims at evaluating crop insurance effects on the farms’ production and investment indicators in Lithuania. The Common Agricultural Policy after 2020 considers measures helping farmers to adapt to climate change. For this reason, it is essential to evaluate existing risk management measures in order to propose appropriate schemes for the next programming period. In order to evaluate crop insurance effects on the farms’ production and investment indicators farm-level, data from Farm Accountancy Data Network dataset and propensity score matching approach was used. Study period was 2008–2017. The study revealed that participation in crop insurance schemes was influenced by the factors such as age of the farmer, wealth, specialization, and location of the farm. The study also demonstrated that crop insurance did not show statistically significant effects on the selected farms’ indicators. The main reason was support from the national and EU funds.

The content of structural carbohydrates and lignin are important assessment criteria of the feed value of meadow plants. It is affected by many independent factors, including among others its development stage during the harvest as well as climatic conditions, especially the amount of rainfall. During the years 2014–2016, plant samples were harvested at weekly intervals, respectively five times from late April to late May. The effect of harvest date on cellulose, hemicelluloses and lignin contents was evaluated. The chemical composition of plants was varied, depending not only on harvest date but also on the year of study. Regardless of the course of meteorological conditions in subsequent growing seasons, the increase of cellulose (from 236.5 to 297.9 g∙kg–1 DM), hemicelluloses (from 159.3 to 210.8 g∙kg–1 DM), and lignin (from 31.5 to 43.1 g∙kg–1 DM) in the following dates of harvest were observed. These parameters were also positively correlated with the total rainfall from the begging of vegetation season to the date of plants sampling (R2 = 0.65, 0.12 and 0.44 for cellulose, hemicelluloses and lignin, respectively), and with the average daily air temperature in the moment of harvest (R2 = 0.66, 0.32 and 0.52 for cellulose, hemicelluloses and lignin, respectively). The cellulose and lignin content, regardless of the harvest date, were significantly higher in the first year of the study (2014), when moisture conditions for plant development were optimal.

According to many experts, the water crisis will be one of the most important challenges in the coming years on the planet. Watershed management is one of the most effective ways to conserve rainwater and develop water resources. The purpose of the study was to obtain a model of critical land management in the Welang watershed area. This study uses a dynamic systems approach based on a causal philosophy (cause and effect) through a deep understanding of how a system works. The parameters used are based on sustainable agriculture in terms of physical sustainability aspects/critical land from erosion factor indicators. Model validation is done by comparing the behaviour of the model with a natural system (quantitive behaviour pattern comparison), namely the Mean Absolute Percentage Error (MAPE) Middle-Value Test. Modelling is supported by Powersim Studio Express Software ver. 10. The results show that the physical sustainability model/critical land using a simulation scenario of 25% erosion control funds shows a trend of increasing production land area and tackled land area followed by a decrease in annual erosion weight. The economic sustainability model obtained results at the end of the projected year showing farm revenues IDR 63,591,396 (USD1 ≈ IDR14.27 thous. in average in 2021). This means that the higher the acceptance value, the farming can provide economic welfare for farmers.

This study aims to evaluate the construction mode of small-scale farmland water conservancy using secondary data from the China statistical yearbook (2000–2019), which was simply and statistically computed. To put it briefly, the simple linear regression model was used to analyse the number of small-scale reservoirs and irrigated areas relative to their capacities and effectiveness. The results showed that the number of small-scale reservoirs increased by 122.2 units of their capacity and the number of small-scale irrigated areas increased by 6.8 units of their effectiveness. The present study introduces the simple linear regression model and accounts for how the number of the small-scale reservoirs and irrigated areas has increased (the total number of reservoirs was 83,260 in 2000 and 98,822 in 2018) relative to their capacity and effectiveness, respectively. Of course, the capacity of water harvesting and the effectiveness of irrigated areas have shown a linear increase over time. Between 2000 and 2019, the capacity increased from 3842 to 7117 for large-scale reservoirs, from 746 to 126 for medium-scale reservoirs, and from 594 to 710 for small-scale reservoirs and their ranges were 3.2, 380, and 116, respectively. Furthermore, the findings of this evaluation provide insights for making decisions on water conservancy interventions.

Anthropogenic pollution leads to increased concentrations of metals in the freshwater and macrophyte. Aquatic plants substantially contribute to the structure, function as well as and service provision of aquatic ecosystems. Our microcosm experiments were to test the possibility of the physiological response of Hydrocharis morsus-ranae to metal (Cd, Pb, Cu, Zn, Mn, Fe at three level of concentration) contaminated waters. Biomass was analysed at the beginning and at the end of the experiment. At the same time contents of photosynthetic pigments in leaves were estimated spectrophotometrically. We found that this macrophyte had the ability to grow in contaminated waters, but the effects of high concentration of isolated metals in water will indicate changes consisting in the disappearance of a significant part of biological populations were which manifested in alteration of the content of photosynthetic pigments as well as this plant’s growth. We show that generally stress of Zn and Cu influenced the drop of dry biomass which was connected with a positive correlation between the amount of dry biomass and the content of chlorophyll a and carotenoids, or only carotenoids, respectively. The highest stress of Pb and Fe (third concentrations of these metals) also influenced the drop of biomass. We concluded that none of Cd concentrations were toxic to this plant, but the effect of Mn stress was not unequivocal. Moreover, plant growth was stimulated by low Fe concentrations (first concentration) demonstrating the hormesis effect. When plants were exposed to this metal, there was no evidence of damage to the photosynthetic processes.