Abstract An interesting reading tends to be a summary of the dominant characteristics of each generation, which can be found in scientific and vocational publications as well as in media with ...popularization texts. Very often, we also identify among them our own characteristics and qualities, or those of our peers, children, and possibly other descendants. It is natural that the development of science and technology has a significant role in shaping the personality profile of the members of each generation during the historical development of society (for example, from the “lost” generation to the “alpha” generation). This factor influences the content, methodological and didactic aspects of the teaching process, i.e. what and how to teach. The authors of the paper have worked on several aspects of the preparation of teaching materials and their use in school physics, often with overlap with other science subjects. One of these aspects is, for example, the need to influence the emotional side of the student in learning processes, which is an important prerequisite for more permanent “inscriptions” of information in the student’s memory. For this process to work, knowledge of the dominant characteristics of the target group of students and the environment in which they grow up is essential.
Thin films of black aluminum (B–Al) were prepared by pulsed DC magnetron sputtering in a mixture of argon + nitrogen (Ar + N2) gases with concentration of nitrogen 6%. At this concentration the ...process of anti-reflective surface (UV to near IR diffuse reflectance below 4%) formation is favored. The properties of such layers have been investigated using methods allowing to follow near-surface processes by means of thermally stimulated desorption (TSD) and thermally stimulated exo-electron emission (TSEE) in ultra-high vacuum conditions (p < 2.10−7 Pa). It is shown that at certain temperatures some adsorbed particles are desorbed and at the same time negative charges are emitted. In some cases, the emission sites are common. Comparison of TSEE measurements at three different excitations (α, proton irradiation and UV illumination) was performed. Common measurements together with calculations of the activation energies of desorption as well as electron emission sufficiently describe the centers responsible for these processes. In particular, the atomic oxygen Oat, the AlOH radical and partly the atomic nitrogen Nat together with the AlN radical are shown to play a significant role in this surface process.
•Combined measurements TSEE and TSD from thin films of black aluminum in UHV.•TSEE measurements made at both laboratories (Riga, Prague) show agreement at T = 168 and 347 °C.•Atomic O, N and radical AlOH showed two TSD stages: below RT - physical desorption.•Atoms and radicals AlOH, Al2O and AlN: above RT released as chemisorbed species.•The AlOH radical shows maxima at T = 97 °C and 271 °C; Al2O, AlN only above T > 300 °C.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Based on the evaluation of data from agricultural operations of 60 enterprises in the period 2012-2016 on 339 516 ha, frequent increases in nutrient dosages for production are mainly in marginal ...areas where higher production than is equivalent to optimal production on the soil is required. In the production of crops, it is most manifest in the production of feed crops, which are often used for the continuous flow of livestock production and biogas stations. Because of the above-standard utilization of fertilizers, yields rise above the level corresponding to the standard conditions for soil-climatic conditions, but also to decrease the efficiency of fertilizer utilization and thus to overload the optimal soil productivity. In contrast, the standard use of fertilizers is reflected in winter wheat, grain corn, triticale, potatoes and rye. Because of the lower strength of the humus horizon in marginal areas, it can be assumed that by increased fertilization, the agricultural enterprises solve the lower sorption capacity of the soil. The overall finding is also a warning to the occupation of quality land for non-agricultural purposes because their intensification cannot be transferred into marginal areas with no environmental impact.
. For wear demanding applications, the coatings, consisting of WC in the nickel-based alloy are often used due to their excellent properties. Nevertheless, there are still limits of these coatings, ...mainly deterioration of tungsten carbide due to heat load during laser cladding. The suppress the limits, a new type of coating material, consisting of the (TiW)C1-x in nickel-based alloy, was designed. The goal of this study is to compare the microstructure and mechanical properties of new (TiW)C1-x based coating with a usual WC-based coating to confirm its improved behaviour.
An increase in surface absorptivity can be helpful with a number of laser heat treatment processes. This study examines the relationship between the surface condition and its influence on interaction ...with a laser beam. The aim of this paper is to examine the effect of the oxide layer pattern size on the absorption of IR radiation and the influence of the ambient atmosphere. The process was carried with inert gas shielding. The oxide layers are created by the controlled heating method. The controlled heating method uses a scanning laser system to create oxide layers of different thickness on steel EN 10083-2: C45. Subsequently, the absorbency of the formed oxide layer was measured, depending on the irradiation energy emitted into the surface. According to recent experiments has been found that the higher the thickness of the oxide layer increases absorption. These results have shown that the use of surface oxidation increases the coupling of laser energy to material surface in the order of tens of percent. The thickness and hardness of the laser hardened layer were considered. That paper describes possibilities of precise laser quenching of the oxidized C45 material surface.
This study examines the influence of surface condition on its interaction with a laser beam. The relation was tested on milled C45 steel samples with a different width of created oxide layer. The ...milled surface with roughness 1.6 was modified by the creation of oxide layer. The oxide layers were created by solid state pulsed laser with scanning optics. The modified samples were processed by high power diode laser with a wide spread beam. The surface temperature was measured by the thermal camera during this process. The surface hardness and hardness depth profile were measured for all modified samples and the emissivity values were measured. The effect of pretreatment on hardness and microstructure will be discussed. The goal of this paper is to describe the relation between the parameters of created oxide layer and its effect on laser beam absorption.
Despite being considered as a key instrument of the agricultural development policy, the investment support has received only limited attention in the Czech economic literature. The objective of this ...paper is to assess economic effects of the measure 121 "Modernisation of Agricultural Holdings" of the RDP 2007-2013 on the Czech farms. A particular focus is on the distribution of the supports and differentiated impacts of the supports according to the production conditions and farm size. The counterfactual approach is adopted, deploying direct matching algorithm with the treatment of hereoscedasticity. We show significant benefits of the investment support in terms of business expansion (represented by Gross value added) and labour productivity improvements. Analysing the sample of applicants for Measure 121 we show that large farms get much larger support than smaller farms. By splitting the sample by natural conditions and by size we demonstrate that benefits are higher on farms in less favoured areas and on medium-size farms in both the absolute and relative terms. Investigating the changes in bank indebtedness we yield an indication that on average the support mobilised additional resources to finance the sector investment. However, there is no statistically significant increase of bank indebtedness on large farms due to investment support. In turn, it can be interpreted that deadweight is rather high on large farms, while on average the deadweight of the investment support programme is rather low. Thus, the programme can improve its social efficiency if it is targeted to small and medium size farms. PUBLICATION ABSTRACT
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CEKLJ, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UL, UM, UPUK
The epithelial-mesenchymal transition (EMT) is intrinsically linked to alterations of the intracellular cytoskeleton and the extracellular matrix. After EMT, cells acquire an elongated morphology ...with front/back polarity, which can be attributed to actin-driven protrusion formation as well as the gain of vimentin expression. Consequently, cells can deform and remodel the surrounding matrix in order to facilitate local invasion. In this review, we highlight recent bioengineering approaches to elucidate EMT and functional changes in the cytoskeleton. First, we review transitions between multicellular clusters and dispersed individuals on planar surfaces, which often exhibit coordinated behaviors driven by leader cells and EMT. Second, we consider the functional role of vimentin, which can be probed at subcellular length scales and within confined spaces. Third, we discuss the role of topographical patterning and EMT via a contact guidance like mechanism. Finally, we address how multicellular clusters disorganize and disseminate in 3D matrix. These new technologies enable controlled physical microenvironments and higher-resolution spatiotemporal measurements of EMT at the single cell level. In closing, we consider future directions for the field and outstanding questions regarding EMT and the cytoskeleton for human cancer progression. Video Abstract.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Nivolumab 3 mg/kg every 2 weeks (Q2W) has shown benefit versus the standard of care in melanoma, non-small cell lung cancer (NSCLC), and renal cell carcinoma (RCC). However, flat dosing is expected ...to shorten preparation time and improve ease of administration. With knowledge of nivolumab safety, efficacy, and pharmacokinetics across a wide dose range in body weight (BW) dosing, assessment of the benefit–risk profile of a 240-mg flat dose relative to the approved 3-mg/kg dose was approached by quantitative clinical pharmacology.
A flat dose of 240 mg was selected based on its equivalence to the 3-mg/kg dose at the median BW of ∼80 kg in patients in the nivolumab program. The benefit–risk profile of nivolumab 240 mg was evaluated by comparing exposures at 3 mg/kg Q2W and 240 mg Q2W across BW and tumor types; clinical safety at 3 mg/kg Q2W by BW and exposure quartiles in melanoma, NSCLC, and RCC; and safety and efficacy at 240 mg Q2W relative to 3 mg/kg Q2W in melanoma, NSCLC, and RCC.
The median nivolumab exposure and its distribution at 240 mg Q2W were similar to 3 mg/kg Q2W in the simulated population. Safety analyses did not demonstrate a clinically meaningful relationship between BW or nivolumab exposure quartiles and frequency or severity of adverse events. The predicted safety and efficacy were similar across nivolumab exposure ranges achieved with 3 mg/kg Q2W or 240 mg Q2W flat dose.
Based on population pharmacokinetic modeling, established flat exposure–response relationships for efficacy and safety, and clinical safety, the benefit–risk profile of nivolumab 240 mg Q2W was comparable to 3 mg/kg Q2W. The quantitative clinical pharmacology approach provided evidence for regulatory decision-making on dose modification, obviating the need for an independent clinical study.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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