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The processes of structural relaxation, crystal growth, and thermal decomposition were studied for amorphous griseofulvin (GSF) by means of thermo-analytical, microscopic, spectroscopic, and diffraction techniques. The activation energy of ~395 kJ·mol−1 can be attributed to the structural relaxation motions described in terms of the Tool–Narayanaswamy–Moynihan model. Whereas the bulk amorphous GSF is very stable, the presence of mechanical defects and micro-cracks results in partial crystallization initiated by the transition from the glassy to the under-cooled liquid state (at ~80 °C). A key aspect of this crystal growth mode is the presence of a sufficiently nucleated vicinity of the disrupted amorphous phase; the crystal growth itself is a rate-determining step. The main macroscopic (calorimetrically observed) crystallization process occurs in amorphous GSF at 115–135 °C. In both cases, the common polymorph I is dominantly formed. Whereas the macroscopic crystallization of coarse GSF powder exhibits similar activation energy (~235 kJ·mol−1) as that of microscopically observed growth in bulk material, the activation energy of the fine GSF powder macroscopic crystallization gradually changes (as temperature and/or heating rate increase) from the activation energy of microscopic surface growth (~105 kJ·mol−1) to that observed for the growth in bulk GSF. The macroscopic crystal growth kinetics can be accurately described in terms of the complex mechanism, utilizing two independent autocatalytic Šesták–Berggren processes. Thermal decomposition of GSF proceeds identically in N2 and in air atmospheres with the activation energy of ~105 kJ·mol−1. The coincidence of the GSF melting temperature and the onset of decomposition (both at 200 °C) indicates that evaporation may initiate or compete with the decomposition process. [ABSTRACT FROM AUTHOR]

The influence of partial crystallinity on the structural relaxation behavior of low-molecular organic glasses is, contrary to, e.g., polymeric materials, a largely unexplored territory. In the present study, differential scanning calorimetry was used to prepare a series of amorphous indomethacin powders crystallized to various extents. The preparations stemmed from the two distinct particle size fractions: 50–125 µm and 300–500 µm. The structural relaxation data from the cyclic calorimetric measurements were described in terms of the phenomenological Tool–Narayanaswamy–Moynihan model. For the 300–500 µm powder, the crystalline phase forming dominantly on the surface led to a monotonous decrease in the glass transition by ~6 °C in the 0–70% crystallinity range. The activation energy of the relaxation motions and the degree of heterogeneity within the relaxing matrix were not influenced by the increasing crystallinity, while the interconnectivity slightly increased. This behavior was attributed to the release of the quenched-in stresses and to the consequent slight increase in the structural interconnectivity. For the 50–125 µm powder, distinctly different relaxation dynamics were observed. This leads to a conclusion that the crystalline phase grows throughout the bulk glassy matrix along the internal micro-cracks. At higher crystallinity, a sharp increase in Tg, an increase in interconnectivity, and an increase in the variability of structural units engaged in the relaxation motions were observed. [ABSTRACT FROM AUTHOR]

The goal of this article is to predict the further development of the market price of farmland in Czechia. As part of this goal, the environmental and socio-economic factors affecting the quantity and quality of farmland and, subsequently, the amount of its market price will be discussed. In addition to the quality of the farmland, the market price of individual plots of land is influenced by a number of other factors, such as the size and shape of the plot, location, erosion risk, the concluded usufructuary lease agreements, competition from buyers in the vicinity, and other factors. The average market price of farmland in Czechia was 29.4 CZK/m2 in 2021, which represents an increase of 16.1% against the amount of 25.3 CZK/m2 in 2020. According to the results of the statistical analysis, it is possible to assume a constant increase in the prices of farmland precisely because of the ever-decreasing area of land intended for agricultural production. Another factor for the increase in prices can be increased inflation. In 2027, market prices for farmland could reach up to 40 CZK per m2. Nevertheless, Czechia is among the countries with the lowest market price of farmland; the price is even lower than in neighboring Poland or Spain. This also contributes to the fact that the market prices of farmland in Czechia are increasing at a relatively fast pace every year. [ABSTRACT FROM AUTHOR]

Differential scanning calorimetry and Raman spectroscopy were used to study the nonisothermal and isothermal crystallization behavior of amorphous indomethacin powders (with particle sizes ranging from 50 to 1000 µm) and their dependence on long-term storage conditions, either 0–100 days stored freely at laboratory ambient temperatures and humidity or placed in a desiccator at 10 °C. Whereas the γ-form polymorph always dominated, the accelerated formation of the α-form was observed in situations of heightened mobility (higher temperature and heating rate), increased amounts of mechanically induced defects, and prolonged free-surface nucleation. A complex crystallization behavior with two separated crystal growth modes (originating from either the mechanical defects or the free surface) was identified both isothermally and nonisothermally. The diffusionless glass–crystal (GC) crystal growth was found to proceed during the long-term storage at 10 °C and zero humidity, at the rate of ~100 µm of the γ-form surface crystalline layer being formed in 100 days. Storage at the laboratory temperature (still below the glass transition temperature) and humidity led only to a negligible/nondetectable GC growth for the fine indomethacin powders (particle size below ~150 µm), indicating a marked suppression of GC growth by the high density of mechanical defects under these conditions. The freely stored bulk material with no mechanical damage and a smooth surface exhibited zero traces of GC growth (as confirmed by microscopy) after >150 days of storage. The accuracy of the kinetic predictions of the indomethacin crystallization behavior was rather poor due to the combined influences of the mechanical defects, competing nucleation, and crystal growth processes of the two polymorphic phases as well as the GC growth complex dependence on the storage conditions within the vicinity of the glass transition temperature. Performing paired isothermal and nonisothermal kinetic measurements is thus highly recommended in macroscopic crystallization studies of drugs with similarly complicated crystal growth behaviors. [ABSTRACT FROM AUTHOR]

Non-isothermal differential scanning calorimetry (DSC) was used to study the influences of particle size (daver) and heating rate (q+) on the structural relaxation, crystal growth and decomposition kinetics of amorphous indomethacin. The structural relaxation and decomposition processes exhibited daver-independent kinetics, with the q+ dependences based on the apparent activation energies of 342 and 106 kJ·mol−1, respectively. The DSC-measured crystal growth kinetics played a dominant role in the nucleation throughout the total macroscopic amorphous-to-crystalline transformation: the change from the zero-order to the autocatalytic mechanism with increasing q+, the significant alteration of kinetics, with the storage below the glass transition temperature, and the accelerated crystallization due to mechanically induced defects. Whereas slow q+ led to the formation of the thermodynamically stable γ polymorph, fast q+ produced a significant amount of the metastable α polymorph. Mutual correlations between the macroscopic and microscopic crystal growth processes, and between the viscous flow and structural relaxation motions, were discussed based on the values of the corresponding activation energies. Notably, this approach helped us to distinguish between particular crystal growth modes in the case of the powdered indomethacin materials. Ediger's decoupling parameter was used to quantify the relationship between the viscosity and crystal growth. The link between the cooperativity of structural domains, parameters of the Tool-Narayanaswamy-Moynihan relaxation model and microscopic crystal growth was proposed. [ABSTRACT FROM AUTHOR]

The present study focused on the more detailed characterization of chitosan–carrageenan-based matrix tablets with respect to their potential utilization for drug targeting in the intestine. The study systematically dealt with the particular stages of the dissolution process, as well as with different views of the physico-chemical processes involved in these stages. The initial swelling of the tablets in the acidic medium based on the combined microscopy–calorimetry point of view, the pH-induced differences in the erosion and swelling of the tested tablets, and the morphological characterization of the tablets are discussed. The dissolution kinetics correlated with the rheological properties and mucoadhesive behavior of the tablets are also reported, and, correspondingly, the formulations with suitable properties were identified. It was confirmed that the formation of the chitosan–carrageenan polyelectrolyte complex may be an elegant and beneficial alternative solution for the drug targeting to the intestine by the matrix tablet. [ABSTRACT FROM AUTHOR]

Common latex coatings suffer from poor water resistance, which often limits their practical application. This paper reports on the preparation of polyacrylate latexes using various approaches to tune the water resistance, wettability, and surface properties of their coating films. The mutual effects of fluorinated monomer copolymerization, emulsifier type (polymerizable and general), and intra- or interparticle covalent crosslinking (due to allyl methacrylate copolymerization and a keto-hydrazide reaction, respectively) were studied. The polyacrylate latexes were synthesized through a two-step semicontinuous emulsion polymerization of 2,2,2-trifluoroethyl methacrylate, butyl acrylate, methyl methacrylate, and methacrylic acid as the basic monomers. The fluorinated monomer was incorporated into the second-step polymer (at a content of 30 wt.% based on the second-step monomer feeds). The water resistance, wettability, and surface properties of the coating films were evaluated with focus on the water absorption, water whitening, water contact angle, and surface topography using atomic force microscopy. It was found that highly water-resistant and hydrophobic coatings that possessed a self-healing ability were prepared, provided that the polymerizable emulsifier and the fluorinated monomer were involved in the latex synthesis, along with the intra- and interparticle covalent crosslinking. [ABSTRACT FROM AUTHOR]

The warming of the planet and ongoing climate change are now a scientifically proven fact. These phenomena have an impact on nature and many human activities, but logically affect agriculture the most. History has confirmed that the production of grapes (the extent and quality) is significantly affected by climate change. The main goal of this study was to evaluate the impact of climate change through changes in average precipitation and average temperatures on the quantity of grape production in the Czech Republic. A partial goal was then to predict the future development of grape production depending on the expected total precipitation and average temperatures. The effect of changes in average temperatures and total precipitation was evaluated using multiple linear regression methods. The multiple regression model did not reveal a dependence of the total precipitation and average temperatures on the development of the value of vine production due to the statistical insignificance of the effect of average temperatures on the value of vine production. However, when abstracting the effect of average temperatures on the value of vine production, the research confirmed the effect of the change in total precipitation on the value of vine production. The analysis identified the effect of changes in total precipitation and temperatures on the production of grapes in the Czech Republic. [ABSTRACT FROM AUTHOR]

The purpose of this study is to express the perspective of development of the hop field area in connection with the growing number of microbreweries and the popularity of special beers in Czechia. Czech beer is a concept all over the world, it comes not only from 45 large industrial breweries, including world-famous breweries from Pilsen, Prague or České Budĕjovice, but is also produced in more than 480 small breweries (microbreweries), many of which are traditional family businesses. With a consumption of 141 L per person in 2018, the Czechs are among the world's largest beer consumers and they have already surpassed even the Irish and Germans. The research performed confirmed the validity of the hypothesis about a slight positive effect of the growth in the number of microbreweries and the production of special beers on the extent of the hop field area in Czechia. In addition to the interpretation of new beer styles, this article also discusses the emergence of new aromatic hop varieties, the development of beer tourism and new sales opportunities for hop growers. [ABSTRACT FROM AUTHOR]

Tablets used for extended drug release commonly contain large amounts of drugs. The corresponding drug release mechanism thus has to be well-known and invariable under numerous conditions in order to prevent any uncontrolled drug release. Particularly important is the stability and invariability of the release mechanism in the presence of alcohol due to the possible occurrence of the dose dumping effect. The effect of 3D printing (3DP) coating on the drug release mechanism and the drug release rate was studied as a possible tool for the prevention of the alcohol-induced dose dumping effect. Three types of matrix tablets (hydrophilic, lipophilic, and hydrophilic-lipophilic) were prepared by the direct compression method and coated using 3DP. The commercial filament of polyvinyl alcohol (PVA) and the filament prepared from hypromellose by hot melt extrusion (HME) were used as coating materials. Both coating materials were characterized by SEM, DSC, Raman spectroscopy, and PXRD during particular stages of the processing/coating procedure. The dissolution behavior of the uncoated and coated tablets was studied in the strongly acidic (pH 1.2) and alcoholic (40% of ethanol) dissolution media. The dissolution tests in the alcoholic medium showed that the Affinisol coating was effective in preventing the dose dumping incidence. The dissolution tests in the acidic dissolution media showed that the Affinisol coating can also be useful for the delayed release of active substances. [ABSTRACT FROM AUTHOR]

The objective of the paper is to evaluate the quality of systemic change management (CHM) and readiness for change in five Central European countries. The secondary goal is to identify trends and upcoming changes in the field of digital innovations in healthcare. The results show that all compared countries (regardless of their historical context) deal with similar CHM challenges with a rather similar degree of success. A questionnaire distributed to hospitals clearly showed that there is still considerable room for improvement in terms of the use of specific CHM tools. A review focused on digital innovations based on the PRISMA statement showed that there are five main directions, namely, data collection and integration, telemedicine, artificial intelligence, electronic medical records, and M-Health. In the hospital environment, there are considerable reservations in applying change management principles, as well as the absence of a systemic approach. The main factors that must be monitored for a successful and sustainable CHM include a clearly defined and widely communicated vision, early engagement of all stakeholders, precisely set rules, adaptation to the local context and culture, provision of a technical base, and a step-by-step implementation with strong feedback. [ABSTRACT FROM AUTHOR]

As our research has shown, the number of foreign tourists visiting Czechia rose in the period between 2012 and 2017, as did hotel occupancy and accommodation prices. The growth of the local economy, the new airlines from Asia and the USA to Prague, and the perception of the Czech metropolis as a safe destination, played a big part in it. Compared to other accommodation facilities, the number of 5- and 4-star hotels is still growing in Czechia, thus better meeting the needs of demanding tourists. According to experience and statistical data, these are non-European tourists and tourists with above-average income. The growth in the number of these tourists had a strong influence on the increase in the number of hotels and the increase in the capacity of the highest-category hotels. Building new, quality hotels, and renovating historical buildings to a higher standard to provide an outstanding experience for foreign tourists staying in Czechia, can contribute to achieving the sustainability of the tourism sector in the country. Also mentioned is the current impact of the coronavirus pandemic on tourism in Czechia. A statistical analysis of time series of indicators and hypothesis testing were the main methods used in the study. [ABSTRACT FROM AUTHOR]

Artificial neural networks (ANNs) are a method of machine learning (ML) that is now widely used in physics, chemistry, and material science. ANN can learn from data to identify nonlinear trends and give accurate predictions. ML methods, and ANNs in particular, have already demonstrated their worth in solving various chemical engineering problems, but applications in pyrolysis, thermal analysis, and, especially, thermokinetic studies are still in an initiatory stage. The present article gives a critical overview and summary of the available literature on applying ANNs in the field of pyrolysis, thermal analysis, and thermokinetic studies. More than 100 papers from these research areas are surveyed. Some approaches from the broad field of chemical engineering are discussed as the venues for possible transfer to the field of pyrolysis and thermal analysis studies in general. It is stressed that the current thermokinetic applications of ANNs are yet to evolve significantly to reach the capabilities of the existing isoconversional and model-fitting methods. [ABSTRACT FROM AUTHOR]

The purpose of this study is to express changes in consumer preferences for certain food products due to the income growth of the population, and to specify the way producers or retailers of these commodities respond to the changes in customer choices. The methodology of this study is based on comparing the economic model of consumer behavior in the market to the analysis of demand elasticity, together with its practical application to food products of the same brand offered by multinational chains in Czechia and Germany. The study presents a new survey, including a comparison of the quality and safety of food products offered by retail chains in Czechia and Germany, and a comparison with similar bio-quality products offered by Czech farmers in their shops or at farmers' markets. As the comparison indicates, unless multinational producers change their current behavior, consumers will prefer purchasing products from Czech producers, including products offered at farmers' markets, and shop in neighboring countries where higher-quality original products may be found. [ABSTRACT FROM AUTHOR]

The aim of this article was to express social and economic aspects of the sustainable livestock production in relation to meat consumption in the Czech Republic and to predict the possibilities of further development of livestock production in the conditions of Czech agriculture. With the accession of Czechia to the EU (2004), the structure of Czech agriculture changed to the detriment of livestock production. The decisive sectors of livestock production are pig breeding, cattle breeding and poultry farming. This article (contribution) analyzes trends in the development of production in the basic categories of livestock, and it evaluates the degree of self-sufficiency of the economy in the given sector of agricultural production and the consumption of individual types of meat in Czechia. Using Holt's model of statistical analysis, it then predicts the future consumption of meat and its individual types in the Czech Republic in the years 2020–2024. As research has shown, the sustainable development of livestock production and meat consumption in the Czech Republic depends not only on the mutual size of meat production and consumption or its quality, but also significantly on the market prices of meat (including world prices), as well as changes in eating habits of the population. [ABSTRACT FROM AUTHOR]

This study aims to calculate the costs of prostate cancer radiotherapy in a regional hospital Department of Radiation Oncology equipped with Three-Dimensional Conformal Radiation Therapy (3D-CRT) and Intensity Modulated Radiation Therapy (IMRT) Volumetric Arc Therapy (VMAT) radiation technology, using activity based costing (ABC), and to compare the costs of both methods at the level of component treatment process activities and with respect to insurance reimbursements. The costing was performed based on a sample of 273 IMRT VMAT patients and 312 3D-CRT patients in a regional hospital in the period from 2018 to 2019. The research has highlighted the necessity to place emphasis on factors that may skew the costing results. The resulting output has been supplemented by a sensitivity analysis, whereas the modeled parameter is represented by the time required for one patient fraction on a linear accelerator and the time the Radiology Assistant needs to prepare the complete radiation plan as part of radiotherapy planning. Moreover, the effects of the received grant, in the form of calculated write-offs, are also considered. The case study uses the example of radiotherapy to demonstrate the potential of ABC and suggests considering the application of this method as an effective management tool for cost and economic evaluation as part of comprehensive hospital assessment under the Hospital-Based Health Technology Assessment (HB-HTA) initiative. [ABSTRACT FROM AUTHOR]

The aim of the presented article is to evaluate the impact of climate change on the sugar content of grapes in the Czech Republic during the period 2000–2019 through selected indicators on the basis of available secondary sources. Attention is focused on the developments in both the main wine-growing regions of Moravia and Bohemia. In the field of viticulture and wine-growing, the sugar content of grapes, as a basic parameter for the classification of wines, plays an important role. In the Czech Republic, the average sugar content of grapes has had a constantly growing trend. This trend is evident both in the wine-growing region of Bohemia and in the wine-growing region of Moravia. The impact of climate change, especially the gradual increase of average temperatures in the growing season, cannot be overlooked. It greatly affects, among other things, the sugar content of grapes. Calculations according to the Huglin Index and the Winkler Index were used to determine the relationship between climate and sugar content. These indexes summarize the course of temperatures during the entire vegetation period into a single numerical value. The results show that both indexes describe the effect of air temperature on sugar content in both wine regions of the Czech Republic in a statistically significant way. The Huglin Index shows a higher correlation rate. The Winkler Index proved to be less suitable for both areas. Alternatively, the Winkler Index calculated for a shorter growing season was tested, which showed a higher degree of correlation with sugar content, approaching the significance of the Huglin Index. [ABSTRACT FROM AUTHOR]

This study presents a comparison of the performance and the ranking of pork producers in 16 countries over the period 2012–2017. Data envelopment analysis (DEA) is used to make the ranking and identify the best practices among the involved countries ("peers"). For the DEA analysis, the output is aggregated into the category Carcass meat production in sow/year/kg, the inputs into Feed costs, Other variable costs, Labor costs, Depreciation and finance costs. In the first round of evaluation, only Brazil, the USA and The Netherlands were designated as peers. Significant differences between the highest-ranking values (1) and the lowest-ranking values (0.709) showed greater differences between European and non-European pork manufacturers. To get more European countries among the peers, non-European countries the USA and Brazil were excluded from the second round of evaluation. The second round of evaluation indicated that Belgium, the Czech Republic, Denmark, Finland, Italy, the Netherlands and Spain are efficient producers with regard to the given inputs. The ratings of Germany, Italy and France are close to one (with differences of less than 4%); therefore, these countries can also be classified as efficient units. The identification of peers among selected EU producers represents "best practices" in the field. [ABSTRACT FROM AUTHOR]

Each year, around 2% of the four million hectares of farmland in Czechia changes owners. However, after years of significant growth in prices, a slowdown in pace and demand is expected. Rising interest rates, a strengthening of the crown and legislative changes in 2018 have influenced the price of farmland. Yet the prices of farmland in Czechia are a third of those in the countries of Western Europe, and so it still represents an interesting opportunity for investors. Currently, land is bought primarily by the farmers who work it. In Czechia, 80% of farmers farm on hired land, and rent increases are starting to be an issue for many of them. The return on the investment in agricultural land is currently around 50 years for an owner and 25 years for a farmer working the land. As research has shown, the price of farmland is an important factor in the sustainable development of agriculture in Czechia, along with the greening of production and the fight against soil erosion and the effects of climate change. [ABSTRACT FROM AUTHOR]

This paper is focused on a simple preparation of functional acrylic latex coating binders comprising embedded nanoparticles originating from ZnO and MgO, respectively, in the role of interfacial ionic self-crosslinking agents. The incorporation of surface-untreated powdered nano-oxides into the coating binder was achieved in the course of the latex synthesis performed by a technique of the two-step emulsion polymerization. By means of this technological approach, latexes comprising dispersed nanoparticles in the content of ca 0.5–1.1 wt % (based on solids) were successfully prepared. For the interfacial covalent self-crosslinking, diacetone acrylamide repeat units were introduced into the latex polymer to ensure functionalities for the subsequent reaction with adipic acid dihydrazide. The latex storage stability and coating performance were compared with respect to the type and concentration of the incorporated nanoparticles. It was determined that all latex coating binders comprising nanoparticles exhibited long-term storage stability and provided interfacially crosslinked transparent smooth coating films of high gloss, excellent solvent resistance, and favorable physico-mechanical properties. Moreover, latexes with embedded nanoparticles, which originated from MgO, manifested a pronounced drop in minimum film forming temperature and provided highly water whitening resistant coating films. [ABSTRACT FROM AUTHOR]

Theoretically simulated kinetic data were used to evaluate the performance of the most common isoconversional methods of kinetic analysis in complex-process scenarios with two independent overlapping processes exhibiting nucleation-growth kinetics, and further expand the conclusions for the autocatalytic kinetic processes with positive asymmetry. In close-to-real-life situations all the integral isoconversional methods provided practically indistinguishable E-α outcomes. The Friedman and incremental modified Vyazovkin methods results in significant over- and undershoots. However, the combined utilization of the integral and differential isoconversional methods was demonstrated to greatly contribute to the interpretation of the E-α dependences and estimation of E1 and E2—the conceptual evaluation involving positions of inflection points and plateaus is introduced. The influence of the range of applied heating rates q+ on the course of E-α dependences was studied. In this regard, the performance of the isoconversional methods changes significantly with both, the consistence of the shape of the complex kinetic curve and weighted presence of full overlaps of the involved sub-processes. [ABSTRACT FROM AUTHOR]

It is expected that viscous flow is affecting the kinetic processes in a supercooled liquid, such as the structural relaxation and the crystallization kinetics. These processes significantly influence the behavior of glass being prepared by quenching. In this paper, the activation energy of viscous flow is discussed with respect to the activation energy of crystal growth and the structural relaxation of glassy selenium. Differential scanning calorimetry (DSC), thermomechanical analysis (TMA) and hot-stage infrared microscopy were used. It is shown that the activation energy of structural relaxation corresponds to that of the viscous flow at the lowest value of the glass transition temperature obtained within the commonly achievable time scale. The temperature-dependent activation energy of crystal growth, data obtained by isothermal and non-isothermal DSC and TMA experiments, as well as direct microscopic measurements, follows nearly the same dependence as the activation energy of viscous flow, taking into account viscosity and crystal growth rate decoupling due to the departure from Stokes–Einstein behavior. [ABSTRACT FROM AUTHOR]