Tomas Bata University in Zlín
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Process-induced morphology of poly(butylene adipate terephthalate)/poly(lactic acid) blown extrusion films modified with chain-extending cross-linkers
Get PDFProcess-induced changes in the morphology of biodegradable polybutylene adipate terephthalate (PBAT) and polylactic acid (PLA) blends modified with various multifunctional chain-extending cross-linkers (CECLs) are presented. The morphology of unmodified and modified films produced with blown film extrusion is examined in an extrusion direction (ED) and a transverse direction (TD). While FTIR analysis showed only small peak shifts indicating that the CECLs modify the molecular weight of the PBAT/PLA blend, SEM investigations of the fracture surfaces of blown extrusion films revealed their significant effect on the morphology formed during the processing. Due to the combined shear and elongation deformation during blown film extrusion, rather spherical PLA islands were partly transformed into long fibrils, which tended to decay to chains of elliptical islands if cooled slowly. The CECL introduction into the blend changed the thickness of the PLA fibrils, modified the interface adhesion, and altered the deformation behavior of the PBAT matrix from brittle to ductile. The results proved that CECLs react selectively with PBAT, PLA, and their interface. Furthermore, the reactions of CECLs with PBAT/PLA induced by the processing depended on the deformation directions (ED and TD), thus resulting in further non-uniformities of blown extrusion films.Ministry of Education, Youth and Sports of the Czech Republic - DKRVO [RP/CPS/2022/003]RP/CPS/2022/003; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠM
Strategic agility, openness and performance: a mixed method comparative analysis of firms operating in developed and emerging markets
Get PDFThis research delineates the relationship between strategic agility and performance, and proposes openness as a requisite means to fostering agility and enhancing performance. Methodologically, the research follows the pragmatist paradigm through a mixed-method research design, incorporating three separate studies. These comprise a CEO-based survey on foreign firms operating in emerging markets, a CEO-based survey on firms operating in developed countries, and CEO interviews, all of which are complimented by auxiliary instruments of secondary data and an expert panel. The research finds that strategic agility is vital for firms' performance in both developed and developing markets. Moreover, we found that while search depth amplifies the above relationship in both contexts, search breadth does it only in the context of foreign firms operating in emerging markets. The value of these findings stems from their elucidation of the role of strategic agility in emerging markets and its comparison to that of firms operating in developed countries; their insights into strategic agility's relationship with openness; their schematic culmination into a systemically and contextually depicted framework; and their prescriptive managerial implications.Universita degli Studi di Torino within the CRUI-CARE AgreementUniversità degli Studi di Torino, UNIT
Proximate chemical composition, amino acids profile and minerals content of meat depending on carcass part, sire genotype and sex of meat rabbits
Get PDFSimple Summary Rabbit meat is popular with consumers mainly for its high-quality protein. Among the main factors influencing the characteristics of rabbit meat proteins to appertain the breed, genotype, carcass part and age. Conventional production of rabbit meat in many European countries is mainly ensured by intensive production systems, when commercial meat-type albinotic rabbit crossbreds are used. However, spotted and solidly coloured lines of meat rabbit breeds have begun to be used in rabbit breeding schemes as some consumers have begun to negatively perceive meat from albinotic coloured rabbits. The aim of the present study was to assess the effects of the sire genotype, sex and carcass part on the composition of meats of rabbits fattened under conditions where no synthetic drugs were used. Crossbreeding of Mecklenburger Schecke sires with a commercial dam line of HYLA rabbits resulted in a worse nutritional quality of meat proteins in progeny. These findings point to a possible risk of alterations in the nutritional quality of meat proteins when using different rabbit sire genotypes than those originally intended for the specific commercial crossbreeding scheme. The aim of the study was to assess the effects of the sire genotype, sex and carcass part on the composition of the meat of rabbits, which were fattened under conditions where no synthetic drugs were used. As for carcass parts, the higher content of both total amino acids (AA) and all essential AA (EAA) monitored was found in the Longissimus thoracis et lumborum (LTL) muscle as compared to hind leg meat (p < 0.001). Significant effects of the rabbit sire genotype and the genotype x sex interaction on proportions of some AA in meat were found (p < 0.001). Crossbreeding of the Mecklenburger Schecke (MS) sires with a commercial dam line of HYLA rabbits resulted in a lower proportion of the total AA and all EAA monitored in meats of MS sired males as compared to MS sired females and HYLA rabbits (p < 0.05). The sex-related effect on AA profile was not so noticeable in final commercial crossbreds of HYLA rabbits when compared to MS sired progeny. These findings point to a possible risk of alterations in the nutritional quality of meat proteins when using different rabbit sire genotypes than those originally intended for the specific commercial crossbreeding scheme. However, on the contrary, higher contents of magnesium (p < 0.05), manganese (p < 0.001) and zinc (p < 0.05) were found in meats of MS sired progeny as compared to HYLA rabbits.Internal Grant Agency of the University of Veterinary Sciences Brno [202/2019/FVHE]202/2019/FVH
Essential factors for building customer relationships on Facebook: Evidence from the Czech Republic
Get PDFE-commerce has become an integral part of the modern age. The behaviour of e-commerce customers has some specifics, which is useful for firms to understand. As customers??? trust and willingness to accept risk influence the decision to buy a product in e-commerce, it is evident that some unique factors must be in e-commerce which is needed to pay attention to be a successful seller. One of the trends affecting how to manage relations with customers is the use of firm profiles on social networks. This paper identifies factors related to the company???s Facebook profile that influence customer Satisfaction and Loyalty in e-commerce. Furthermore, non-traditional factors such as Self-efficacy or Data security are used. The study provides a primary basis for further research in this area. Data collection was done among e-commerce customers using a questionnaire survey (n = 602). For data analysis, structural equation modelling (SEM) was used. The determined construct contained a total of 9 variables. The findings confirmed that the following factors affect customer satisfaction and loyalty: the perceived usefulness and the amount of information on the Facebook company profile, the perceived Credibility of information given on this profile, the Data security offered by the social network, customer Self-efficacy and Ease of use of the given social network. The results supported the idea that it is possible to build relationships with customers in e-commerce via social networks. To offer credible information in an adequate frequency on the company profile is essential. Furthermore, it is helpful to consider customers??? perceived safety and Self-efficacy, which have also proven to be important in the online environment. These results can serve business practice
Modification of the school curriculum as an opportunity for the elitism of gifted students
Get PDFElitism in education is often applied by a different and prefered approach to students belonging to the so-called elite. This elite is segregated and developed, often at the expense of the needs of other students. Can elitism be one of the problems of pedagogical practice with intellectually gifted students in ordinary inclusive primary schools? We carried out qualitative research in the environment of ordinary primary schools by observing school lessons and interviews with teachers. We spent 70 hours in eight schools, tracking 24 gifted students. The aim was to identify and describe the pedagogical situations leading to the elitism of gifted pupils. We focused on teachers as the creator of a modified curriculum for gifted pupils, which gives space for the emergence of elitism. We analyzed the data using open and axial coding. We found that teachers apply pedagogical situations leading to the elitism of gifted pupils, in all components of the modified curriculum, but especially in pedagogical strategies such as extracurricular activities, gifted as a teacher's assistant, complementary tasks and group work. Finally, the features of the curriculum leading to elitism are defined. Research highlights one of the negative consequences of increasing formal support of giftedness. © 2021 Charles University in Prague - Karolinum Press. All rights reserved
Organic food purchase behavior: In the light of the theory of planned behavior, does pro-social attitude matter?
No full textThis research presents a conceptual framework for exploring the role of pro-social attitude in encouraging organic food purchase behavior. An extensive review of the 62 relevant articles downloaded from the Scopus database and purified by a cluster of specific requirements contributes to the development of the conceptual model. Based on the traditional theory of planned behavior, this proposed framework can determine the drivers of organic food purchase behavior. This paper provides a proposed conceptual framework for researchers to empirically test and understand the antecedents of organic food purchase intention of Vietnamese customers in particular and in customers in other developing countries in general. The relationship of pro-social attitudes, attitudes towards pro-environmental behavior, subjective norm, perceived behavior control, pro-environmental intention, and organic food purchase behavior can be discussed. The study also gives a deep insight into the critical determinants for organic food in Vietnam, enhancing managers in assessing the condition and possible determinants that would lead to the successful adoption of customers. However, there are still some limitations. This paper makes progress in the stage of literature review and conceptual model development. Therefore, it is essential to have fundamental experimental research to evaluate the proposed conceptual framework and approve the consequences for the situation of developing countries.Internal Grant Agency of FaME TBU in Zlin [IGA/FaME/2020/011]; Southeast Asia regio
Dual patterning of self-assembling spider silk protein nanofibrillar networks
Get PDFSelf-assembly of a recombinant spider silk protein into nanofibrillar networks in combination with photolithography is used to produce diversely functionalized micropattern. Amino-modified substrates coated with a positive tone photoresist are processed into 1 mu m deep arbitrarily shaped microwells, at the bottom of which spider silk proteins are covalently coupled to the deprotected aminated surface. The protein layer serves to seed the self-assembly of nanofibrils from the same protein in the microwells, forming immobilized few nanometers thin networks after the stripping of the photoresist. The nanofibrous micropattern can be functionalized by employing fluorescently modified spider silk variants during the self-assembly or by later covalent modification with nucleic acids. By repeating the photolithography and fibril assembly procedures, two functionally different and spatially defined pattern are created.Bavarian-Czech Academic Agency (Bayerisch-Tschechische Hochschulagentur) BTHA Grant [JC-2019-21]; Czech Science Foundation [22-33307S]; TBU Grant [IGA/FT/2022/009]; Projekt DEALJC‐2019‐21; Tomas Bata University in Zlin, TBU: IGA/FT/2022/009; Grantová Agentura České Republiky, GA ČR: 22–33307
Blood oxygen concentration and physiological data changes during motion while wearing face masks
Get PDFThe study of physiological changes recorded by wearable devices during physical exercises belongs to very important research topics in neurology for the detection of motion disorders or monitoring of the fitness level during sports activities. This paper contributes to this area with studies of the effect of face masks and respirators on blood oxygen concentration, breathing frequency, and the heart rate changes. Experimental data sets include 296 segments of their total length of 60 hours, recorded on a home exercise bike under different motion conditions. Wearable instruments with oximetric, heart rate, accelerometric, and thermal camera sensors were used to fill the own database of signals recorded with selected sampling frequencies. The proposed methodology includes fundamental signal and image processing methods for signal analysis and machine learning tools for labeling image components and detecting facial temperature changes. Results show the minimal effect of mask wearing on blood oxygen concentration but its substantial influence on the breathing frequency and the heart rate. The use of a respirator substantially increased the respiratory rate for the given set of experiments under the load. This indicates how wearable sensors, computational intelligence, and machine learning can be used for motion monitoring and data analysis of signals recorded in different conditions
Exploring the association between trust and contracting in agribusiness sector: Evidence from Albania
Get PDFThis paper seeks to explore the association between trust in the main buyer and contract farming in the agribusiness sector. Despite numerous studies in this field, there is no consensus among scholars, which is the motivation behind undertaking the present study. The research is based on primary data collected through a structured survey in Albania (640 respondents) during December 2019 and January 2020. Several methods were used to examine the relationship between trust and contract farming, including factor analysis, a reliability test, and a non-parametric statistical technique. The results show that trust and contracting have a significant relationship in the context of the agribusiness sector. Moreover, the findings demonstrate that there is a positive correlation, meaning that those with a verbal or written contract exhibit higher trust than those without any prior agreement to sell the product. The scientific contribution of this study is that it presents further arguments and justifications to a controversial discussion and sheds light on a little-studied context such as Albania. © 2021, Centre of Sociological Research. All rights reserved
Nutritional analysis of red-purple and white-fleshed pitaya (hylocereus) species
Get PDFPitaya is one of the most preferred and produced tropical fruit species recently introduced to the Mediterrranean region in Turkey. Due to its nutritional fruits with high economic value, the popularity of pitaya increases steadily in Turkey as an alternative crop. No detailed nutritional analysis has been undertaken in Turkey so far on fruits of the pitaya species. In this study, we determined and compared some nutritional parameters in fruit flesh of two pitaya (dragon fruit) species (Hylocereus polyrhizus: Siyam and Hylocereus undatus: Vietnam Jaina) grown in the Adana province located in the eastern Mediterranean region in Turkey. The individual sugars, antioxidant activity, total phenolic content, phenolic compounds and volatiles were determined for the first time in Turkey on two pitaya species. The results showed that total phenol content and antioxidant capacity are notably higher in red-fleshed fruits than white-fleshed ones and the predominant phenolic compound in fruits of both species was quercetin. The total sugar content and most of the phenolic compounds in fruits of two pitaya species were similar. A total of 51 volatile compounds were detected by using two Solid Phase Micro Extraction (SPME) fibers, coupled with Gas Chromatography Mass Spectrometry (GC-MS) techniques, and more volatile compounds were presented in the white-fleshed species. Total phenolic content (TPC) of the red-fleshed and white-fleshed pitaya species were 16.66 and 17.11 mg GAE/100 g FW (fresh weight). This study provides a first look at the biochemical comparison of red-fleshed and white-fleshed pitaya species introduced and cultivated in Turkey. The results also showed, for the first time, the biochemical content and the potential health benefit of Hylocereus grown in different agroecological conditions, providing important information for pitaya researchers and application perspective. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.FBA-2019-11325; IGA/FT/2022/004Cukurova University Scientific Research Projects (Turkey) [FBA-2019-11325]Cukurova University Scientific Research Projects (Turkey) [FBA-2019-11325