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  • Author: Zbigniew Mazur x
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Abstract

The work presents the results of carbon dioxide measurements in soil air in a pot experiment during the vegetation of radish and lettuce, fertilized with fish composts along with additional mineral fertilization. In comparison to the C02 content in the control group, fertilization with the compost resulted in a O.10% average increase of this chemical compound in the group lacking mineral fertilization, and 0.12% in the group fertilized with minerals during radish vegetation. The increase in the C02 content of the after-crop (lettuce) was 0.17% and 0.11% (vol. %), respectively.

Summary

Study aim: the aim of the study was to compare two methods for measuring punching and kicking force and the reaction time of athletes.

Material and methods: both systems were designed to measure and to analyse the mechanical characteristics of punches and strikes delivered by upper and lower limbs to a punching bag. The main difference between both punching bags was the way in which the delivered force was measured. The first method used strain gauges while the second method used accelerometer technology. Both systems consisted of a punching bag with software, attached signal diodes, and either embedded accelerometers or strain gauges. The bags were of different sizes. Acceleration transducers and gyroscopes or strain gauges were placed inside the punching bags, which allowed for measuring dynamics while the bag was struck. The software calculated strike force, the point of force application and its direction, and reaction time. Both systems were tested.

Results: the results of the accelerometer-based method show that the mean relative error of force calculation amounts to 3%. The measurement error of acceleration is less than 1%. The mean relative measurement error of the striking surface on the punching bag is 2%. However, the measurement error of force recorded with the strain gauge-based method is less than 1%. The results show that both systems are similar.

Conclusions: the punching bag having an embedded accelerometer is equipped with more versatile software, which makes the system a good tool for practical application in combat sport training.

Abstract

Zero-valent iron (ZVI) represent a promising agent for environmental remediation. The research was aimed to determine the influence of copper in doses of 0, 80, 150, 300, and 600 mg Cu·kg−1 of soil as well as ZVI, and lignite additives on the content of macroelements in the Indian mustard (Brassica juncea (L.) Czern.). The average accumulation of analyzing elements in Indian mustard grown in copper contaminated soil were found to follow the decreasing order Mg > Na > P > Ca > K > N. Soil contamination at 600 mg Cu·kg−1 of soil led to the highest increase in P, Mg, N, and Ca content. The application of ZVI had a positive influence on the average phosphorus and potassium content of Indian mustard. Moreover, the application of ZVI and lignite had a positive influence on the average Mg and Ca content in the above-ground parts of Indian mustard. From the analyzed reactive materials, the application of lignite was shown to be the most effective resulting in the decrease in the average nitrogen and calcium content when compared to the control crop. Calcium content in plants from the control group, without the addition of zero-valent iron, and powered lignite (control), was positively correlated with increasing doses of copper.

Abstract

The objective of the paper was to determine the impact of the value of the oil pressing pressure with the cold pressing method in a screw press on the pressing course and performance. Varied values of pressure were obtained through the use of three replaceable attachments of the pressing unit with a varied diameter of the outlet conduit (ф1=2 mm, ф2=4 mm and ф3=6 mm). The soya oil pressing process performance was determined in relation to the applied attachment and the soya cultivar. Seeds of 7 Polish non-genetically modified soya cultivars constituted research material. It was proved that both variable pressure values and the used soya cultivars have impact on the pressing performance. Based on the analysis of the obtained research results it was proved that varied technical parameters and soya cultivars influence both the process performance and the remaining parameters and pressing conditions.

Abstract

In this work the physicochemical and biological properties of nanocrystalline TiO2 thin films were investigated. Thin films were prepared by magnetron sputtering method. Their properties were examined by X-ray diffraction, photoelectron spectroscopy, atomic force microscopy, optical transmission method and optical profiler. Moreover, surface wettability and scratch resistance were determined. It was found that as-deposited coatings were nanocrystalline and had TiO2-anatase structure, built from crystallites in size of 24 nm. The surface of the films was homogenous, composed of closely packed grains and hydrophilic. Due to nanocrystalline structure thin films exhibited good scratch resistance. The results were correlated to the biological activity (in vitro) of thin films. Morphological changes of mouse fibroblasts (L929 cell line) after contact with the surface of TiO2 films were evaluated with the use of a contrast-phase microscope, while their viability was tested by MTT colorimetric assay. The viability of cell line upon contact with the surface of nanocrystalline TiO2 film was comparable to the control sample. L929 cells had homogenous cytoplasm and were forming a confluent monofilm, while lysis and inhibition of cell growth was not observed. Moreover, the viability in contact with surface of examined films was high. This confirms non-cytotoxic effect of TiO2 film surface on mouse fibroblasts.

Abstract

Introduction: The influence of feeding genetically modified MON 810 hybrid maize on the growth and haematological and biochemical indices of rats was tested.

Material and Methods: Two conventional (non-GM) and two test (MON 810) lines of maize were used in semi-purified diets at the level of 40% w/w. The non-GM I, MON 810 I, non-GM II, and MON 810 II maize lines were near-isogenic. A total of 40 male 6-week-old Wistar-derived rats were assigned to four equal feeding groups corresponding to the four maize lines for 16 weeks. Overall, health, body weight gain, clinical pathology parameters, gross changes, and appearance of tissues were compared between groups.

Results: There were no statistically significant differences in the weight gain or relative organ weights of rats, but there were some non diet-related histopathological changes in the liver, kidneys, and spleen. Except for creatinine level, no diet-related effects were observed in haematology or most of the biochemical indices. Transgenic DNA of MON 810 maize was not detected in the tissues or faeces nor in the DNA of E. coli isolated from the rectum digesta of rats given transgenic feeds. In our experiment, various metabolic indices of rats fed non-GM diets or genetically modified (MON 810) maize for 16 weeks were similar. No adverse nutrition-related health effects were detected.

Conclusion: MON 810 maize seems to be as safe as the conventional maize lines.