9 research outputs found

    Polska, Ukraina, świat

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    Od Wydawcy: "Krakowska Szkoła Wyższa im. Andrzeja Frycza Modrzewskiego, największa niepubliczna szkoła wyższa w Małopolsce od początku swego powstania przywiązuje wagę do kontaktów z uczelniami zagranicznymi. Współpraca nawiązana z wieloma partnerami zagranicznymi nie tylko pozwoliła kadrze dydaktycznej i studentom Frycza nawiązać interesujące kontakty naukowe i biznesowe, wzbogacić księgozbiór o specjalistyczne publikacje, ale zaowocowała także wieloma cennymi programami. Współpraca Szkoły z Międzynarodowym Uniwersytetem REG I im. Akademika Stepana Demianczuka w Równem na Ukrainie - pierwszym partnerem zagranicznym, z którym umowę podpisano w grudniu roku 2001 - przebiega na wielu płaszczyznach (wymiana studentów i pracowników, udział w konferencjach, wspólne publikacje). Owocem jej je st też poniższa książka Polska, Ukraina, Świat pod redakcją Klemensa Budzowskiego i Anatolija Stiepanowicza Demianczuka, zawierająca dorobek naukowy pracowników obu uczelni."(...

    Different Approaches to Oxygen Functionalization of Multi-Walled Carbon Nanotubes and Their Effect on Mechanical and Thermal Properties of Polyamide 12 Based Composites

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    In this work the preparation of polyamide 12 (PA12) based composites reinforced with pristine and surface-modified carbon nanotubes is reported. A qualitative and quantitative evaluation of multi-walled carbon nanotube functionalization with oxygen containing reactive groups achieved by different procedures of chemical treatment is presented. Simple strong oxidative acid treatment as well as chlorination with subsequent chloroacetic acid treatment were applied. Carbon nanotubes (CNTs) were also subjected to chlorine and ammonia in gaseous atmosphere with small differences in after-ammonia treatment. Commercial COOH-functionalized carbon nanotubes were compared with nanotubes that were laboratory modified. The effect of CNT functionalization was evaluated basing on the improvement of mechanical and thermal properties of polyamide 12 composites prepared by in situ polymerization. It was found that high concentration of oxygen-containing functional groups on nanotube surface is not sufficient to improve the composite performance if the structure of carbon nanotubes is defective. Indeed, the best effects were achieved for composites containing nanotubes modified under mild conditions, seemingly due to a compromise between morphology and surface chemical structure

    Chlorination of Carbon Nanotubes Obtained on the Different Metal Catalysts

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    In this paper, a chlorination method is proposed for simultaneous purification and functionalization of carbon nanotubes, thus increasing their ability to use. Carbon nanotubes were obtained by CVD method through ethylene decomposition on the nanocrystalline iron or cobalt or bimetallic iron-cobalt catalysts. The effects of temperature (50, 250, and 450°C) in the case of carbon nanotubes obtained on the Fe-Co catalyst and type of catalyst (Fe, Co, Fe/Co) on the effectiveness of the treatment and functionalization were tested. The phase composition of the samples was determined using the X-ray diffraction method. The quantitative analysis of metal impurity content was validated by means of the thermogravimetric analysis. Using X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive Spectroscopy (EDS) analysis, and also Mohr titration method, the presence of chlorine species on the surface of chlorinated samples was confirmed

    Synergistic and antagonistic effects between biosurfactants from the group of soforolipids and alkylopolyglikosides of various alkyl chain lenghts and their use in the design of cleaning agents for the food industry

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    The paper presents the results of testing the performance parameters of mixtures of biosurfactants from the group of sophorolipids and alkylpolyglycosides with different alkyl chain lengths. In order to determine the synergistic and antagonistic effects in two-component surfactant systems, research was carried out to determine the performance parameters determining their use in washing preparations, such as foam height (FH) and foam stability (FS) and wetting angle analysis (CA). The results are presented in tables 3, 4 and 5. Determination of the content of the active substance in the raw material samples was carried out using the method of refractometric determination of the refractive index. Both synergistic and antagonistic effects were found. On the basis of the obtained test results, the highest synergistic effect of performance parameters was obtained for the mixture of biosurfactants from the group of sophorolipids and the alkylpolyglycoside D-glucopyranose, oligomer, C10-16-alkylglycosides. In this case, the synergy occurred for all performance parameters FH (14%), FS (28%) and CA (46%). The synergistic effects were used to design a concentrated formulation of a cleaning agent in the food industry. The planned experiment method was used in order to obtain an optimal solution in terms of ensuring the appropriate level of cleaning efficiency. A twenty-two-point experiment plan was developed based on the Scheff model in order to optimize the composition in terms of obtaining the operational parameters of the mixture constituting the formulation's framework assumed in the optimization criteria. Optimization criteria were determined on the basis of studies of commercially available analogues. Thanks to the use of formulations of raw materials exhibiting synergistic effects in the design of the frame, the foam height and stability higher than those specified in the optimization criteria were obtained

    Biologically Active Preparations from the Leaves of Wild Plant Species of the Genus Rubus

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    The plants of the genus Rubus (R.) are applied as antiseptic agents in the treatment of skin diseases. Despite the great interest in plants of this genus, there are few reports on the antioxidant and biological activities of preparations obtained from the leaves of these plants. Therefore, we decided to evaluate the antioxidant activity of preparations from leaves of wild plant species of the genus Rubus using the frequently applied DPPH, ABTS, and FRAP methods, as well as to determine the total polyphenol content using the Folin–Ciocalteau method and perform qualitative evaluation by gas chromatography–mass spectrometry (GC-MS). The bactericidal and fungicidal activities of the obtained preparations were evaluated by applying laboratory tests: using the disc and the well methods based on the standards EN 13697:2019, EN 13697:2015, and EN 1500:2013. Microbiological tests of the plant preparations against bacteria, fungi, and yeasts isolated from the environment and against reference strains were performed. Moreover, antimicrobial testing of antibiotics against the tested strains was performed for comparison. The n-octanol/water partition coefficient of the obtained preparations was determined by the shake-flask method to determine their lipophilicity. According to the results, a high content of polyphenols and other antioxidant and biologically active compounds can be thought of as the parameter responsible for the effective activity of plant preparations obtained from wild plant species of the genus Rubus. The methods for determining bactericidal and fungicidal activity clearly demonstrates that preparations with reduced ethanol content exhibit bactericidal and fungicidal activity on surfaces. Testing of hand disinfection by means of rubbing with the preparations confirmed their antimicrobial activity against Escherichia coli K12 NCTC 10538. The obtained results show that the tested preparations exhibit on average two times lower activity against the reference bacterial strains than comparable antibiotics. The preparations obtained from the leaves of R. idaeus L. and R. fruticosus L. could complement classical antibiotics. While environmental bacteria showed a similar response to the preparations and antibiotics, their sensitivity was about one-third less than that of the reference strains. Our studies have shown that the obtained preparations are highly hydrophilic (logP < 0). Thus, these preparations can only be used in lipid bilayers in the aqueous core of liposomes, not in the lipid envelope

    Enhancement of the Antioxidant and Skin Permeation Properties of Betulin and Its Derivatives

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    This study investigated the antioxidant activity DPPH, ABTS, and Folin–Ciocalteu methods of betulin (compound 1) and its derivatives (compounds 2–11). Skin permeability and accumulation associated with compounds 1 and 8 were also examined. Identification of the obtained products (compound 2–11) and betulin isolated from plant material was based on the analysis of 1H- NMR and 13C-NMR spectra. The partition coefficient was calculated to determine the lipophilicity of all compounds. In the next stage, the penetration through pig skin and its accumulation in the skin were evaluated of ethanol vehicles containing compound 8 (at a concentration of 0.226 mmol/dm3), which was characterized by the highest antioxidant activity. For comparison, penetration studies of betulin itself were also carried out. Poor solubility and the bioavailability of pure compounds are major constraints in combination therapy. However, we observed that the ethanol vehicle was an enhancer of skin permeation for both the initial betulin and compound 8. The betulin 8 derivative showed increased permeability through biological membranes compared to the parent betulin. The paper presents the transformation of polycyclic compounds to produce novel derivatives with marked antioxidant activities and as valuable intermediates for the pharmaceutical industry. Moreover, the compounds contained in the vehicles, due to their mechanism of action, can have a beneficial effect on the balance between oxidants and antioxidants in the body, minimizing the effects of oxidative stress. The results of this work may contribute to knowledge regarding vehicles with antioxidant potential. The use of vehicles for this type of research is therefore justified

    Recent Insights and Recommendations for Preventing Excessive Gestational Weight Gain

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    Recommendations for weight gain during pregnancy are based on pre-pregnancy body mass index (BMI). Pregnancy is a risk factor for excessive weight gain and many endocrine problems, making it difficult to return to pre-pregnancy weight and increasing the risk of postpartum obesity and, consequently, type 2 diabetes and metabolic syndrome. Both excessive gestational weight gain (EGWG) and obesity are associated with an increased risk of gestational hypertension, pre-eclampsia, gestational diabetes, cesarean section, shoulder dystocia, and neonatal macrosomia. In the long term, EGWG is associated with increased morbidity and mortality, particularly from diabetes, cardiovascular disorders, and some cancers. This study aims to present recommendations from various societies regarding weight gain during pregnancy, dietary guidance, and physical activity. In addition, we discuss the pathophysiology of this complication and the differential diagnosis in pregnant women with EGWG. According to our research, inadequate nutrition might contribute more significantly to the development of EGWG than insufficient physical activity levels in pregnant women. Telehealth systems seem to be a promising direction for future EGWG prevention by motivating women to exercise. Although the importance of adequate pre-pregnancy weight and weight gain during pregnancy is well known, an increasing number of women gain excessive weight during pregnancy
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