The aim of this article is to examine how poetry, in the case of Paul Celan, created its own language after the Shoah. The thesis is that Paul Celan intentionally uses religious language to expose ...the object, but at the same time he desacralises it. This shift is revolutionary. In the main part of this article I analyse an exemplum of the use of language which is given in the poem, 'In the rivers'. This analysis is meant to show the mechanisms for creating a proper language. The conclusion is that Celan's poetry is founded upon the figure of a witness. This desacralised figure is poetic and ethical (but not substantial). What is more, the way this poetry is written puts it into the position of a witness as well as that of the reader. This is a social fact, so the point of view of the author traverses the sociology of both religion and that of literature.
An increasing percentage of ethanol in fuel leads to significant changes in polarity and solubility, which makes conventional gasoline deposit control additives (DCAs) difficult to dissolve in ...ethanol fuels, resulting in the formation of deposits on engine elements. Critical areas of deposit formation in an engine are constituted by inlet valves, combustion chambers, and fuel injectors. As a consequence, operational parameters of the engine are disturbed to a large extent by the total effect of the deposits. To prevent the aforementioned phenomena, in the operation of engines fueled with ethanol-containing blends, it is necessary to use specifically prepared DCAs. The paper briefly presents a process of development of DCAs dedicated to high-ethanol fuels. Each of the prepared DCA formulations contained a substance having detergent-emulsifying properties (referred to in the text as DEM), a carrier oil, and a solvent. The composition and ratios of components used in the DCA, by testing their effectiveness in engine deposit formation, are verified. A motor station and a test procedure developed for this purpose were used. In search of alternative solutions to conventional polyisobutyleneamines (PIBA) and polyetheramines (PEA) surfactants, which have good solubility in hydrocarbons but not in ethanol, a substance with a benzoxazine structure and a Mannich base were synthesized. Their chemical structures were confirmed by nuclear magnetic resonance (NMR) DCAs were developed, and the effectiveness of their action was verified. Moreover, attention was paid to the dosage level of the DEM and the carrier oil in the DCA. Finally, it was confirmed in the studies carried out that DCAs used for improvement of conventional hydrocarbon engine gasolines are not efficient enough when used in E85 fuels. In the case of the latter, DCAs that have been specifically developed for such fuels should be used, because they have a different chemical structure, and are soluble in the ethanol-gasoline mixture in any ratio of both components.
The main aim of this study is to investigate the effect of fragmentation of electrospun carbon nanofibers (eCNFs) obtained at different temperatures, i.e., at 750 °C, 1000 °C, 1500 °C, 1750 °C and ...2000 °C on the cellular response in vitro. In order to assess the influence of nanofibers on biological response, it was necessary to conduct physicochemical, microstructural and structural studies such as SEM, XPS, Raman spectroscopy, HRTEM and surface wettability of the obtained materials. During the in vitro study, all samples made contact with the human chondrocyte CHON-001 cell lines. The key study was to assess the genotoxicity of eCNFs using the comet test after 1 h or 24 h. Special attention was paid to the degree of crystallinity of the nanofibers, the dimensions of the degradation products and the presence of functional groups on their surface. A detailed analysis showed that the key determinant of the genotoxic effect is the surface chemistry. The presence of nitrogen-containing groups as a product of the decomposition of nitrile groups has an influence on the biological response, leading to mutations in the DNA. This effect was observed only for samples carbonized at lower temperatures, i.e., 750 °C and 1000 °C. These results are important with respect to selecting the temperature of thermal treatment of eCNFs dedicated for medical and environmental functions due to the minimization of the genotoxic effect of these materials.
This study presents the effect of raspberry pomace and its grinding level on microbial activity in the gastrointestinal tract as well as on the parameters involved in the regulation of lipid and ...glucose metabolism in Wistar rats. The nutritional experiment was performed using 24 male Wistar rats, which were divided into 3 groups of 8 animals each. The animals were fed a standard diet (C) or a modified diet containing 7% raspberry pomace subjected to standard (SG) or fine (FG) grinding. Finer grinding increased the concentration of polyphenols and altered the composition of the dietary fibre, thereby affecting the intestinal microbial activity and related mechanisms that regulate systemic parameters. The FG diet considerably increased the level of total ellagitannin metabolites in the colon (23.56 μg/g for SG and 79.54 μg/g for FG) and plasma (0.029 μg/mL for SG and 0.041 μg/mL for FG) and reduced β-glucuronidase and α-glucosidase activity (19.2 and 19.7 for SG and 13.3 and 8.7 μmol/h/g for FG, respectively) and short-chain fatty acid production (55.84 μmol/g for SG and 48.60 μmol/g for FG) in the caecum. Compared to the SG, the FG diet improved the antioxidant capacity of water-soluble substances in plasma (4.34 μg/mL for SG and 4.92 μg/mL for FG). Both diets with raspberry pomaces increased the plasma HDL cholesterol (0.48 mmol/L for C, 0.56 mmol/L for SG, 0.57 mmol/L for FG) and decreased the atherogenic index (AI = (TC-HDL)/HDL: 2.57 for C, 1.98 for SG, 2.00 for FG). The FG diet resulted in the lowest plasma glucose level (10.8 mmol/L for C, 8.2 mmol/L for SG, 7.3 mmol/L for FG). In conclusion, both diets with raspberry pomaces modulated intestinal microbial activity and related systemic parameters; however, FG pomace exhibited greater inhibitory effects than SG pomace in the lower gut environment and glucose metabolism.
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•The grinding level of raspberry pomace has an effect on microbiota activity.•Raspberry pomaces favourable modulates the plasma lipid profile.•Finely ground raspberry pomace reduces the plasma glucose level.•Finer grinding of raspberry pomace improve the antioxidant status in plasma.
The main goal of this research is to create nanocomposites based on unmodified and iron-modified (FeNP) montmorillonite (Mt) and carbon nanotubes (CNT) synthesized using the chemical vapor deposition ...method. The target area for the application of these materials is the creation of water treatment systems. This paper compares the efficiency of the CNT synthesis process on Mt before and after modification with FeNP of different concentrations and provides the characterization of the CNT microstructure and structure using different methods, such as scanning electron microscopy, high-resolution transmission electron imaging, and Raman spectroscopy. For initial verification of properties important for water purification, Mt+CNT and Mt+FeNP+CNT nanocomposites on a carbon nonwoven fabric (CF) are tested in this work. Incubation of the above-mentioned samples in a water–oil mixture reveals complex adsorption dynamics. The CF+Mt+FeNP+CNT sample shows a very good oil adsorption capacity due to its superhydrophobic and oleophilic properties.
Increased awareness of the importance of health promoting compounds in processed fruit products has led to the creation of novel products, such as smoothies, containing the majority of phenolics and ...fibre from fruits. It is important to evaluate the impact of traditional and modern thermal preservation methods on the quality of these novel products. Thermal treatment technologies (microwave flow, flow and batch pasteurization) were tested on apple-based smoothies of different composition: apple smoothies containing rosehip juice or wild blueberry juice. Smoothies with rosehip juice exhibited a higher total phenolics content than those with the addition of blueberry juice, but the differences were insignificant. Anthocyanins content measured in the smoothies with blueberry juice strongly depended on the preservation method used; the highest anthocyanins content was found in microwave preserved smoothies. Ascorbic acid content in the juices was the highest in flow-pasteurized juices (29 mg/100 g), while microwave treatment caused a significant decrease (20 mg/100 g). The effect of thermal processing on viscosity was also observed; microwave flow-pasteurized smoothies were characterized by higher viscosity and total pectins than those preserved by the other methods. This suggests that the preservation process interacts with microstructure and can affect smoothie quality during its shelf-life.
•Smoothies compared to typical juices are rich in soluble and insoluble fiber.•Addition of juices from valuable fruits can enhance health value of apple products.•Investigated pasteurization methods are comparable in respect to smoothie quality.
Head and neck squamous cell cancer (HNSCC) represents a significant burden worldwide. Chemoprevention of HNSCC is a means of cancer control with a use of drugs or natural agents in order to hinder or ...delay the cancer development. The purpose of this article is to review mechanism of action of different chemopreventive agents’ groups and results of most important researches concerning them. The safety issues of HNSCC chemoprevention are also discussed. In case of HNSCC there is currently no agent, which would give positive result in the third phase of clinical trials. Promising results of preclinical trials are not always confirmed by further tests. Main problems are low effectiveness, high toxicity, and lack of highly specificity biomarkers for monitoring the research. New trials concerning many agents, as well as novel technologies for provision of pharmaceutical forms of them, including drug nanocarriers, are currently underway, which gives hope for finding the perfect chemopreventive agent formula.
The goal of this study is to investigate the influence of different types of modifiers, such as sodium hyaluronate (NaH), graphene oxide (GO), silica oxycarbide (SiOC) and oxidation process (ox) on ...physicochemical, morphological, and biological properties of electrospun carbon nanofibers (eCNFs). Scanning electron microscopy, X-ray photoelectron spectroscopy and infrared spectroscopy (FTIR) were used to evaluate the microstructure and chemistry of as-prepared and modified CNFs. The electrical properties of CNFs scaffolds were examined using a four-point probe method to evaluate the influence of modifiers on the volume conductivity and surface resistivity of the obtained samples. The wettability of the surfaces of modified and unmodified CNFs scaffolds was also tested by contact angle measurement. During the in vitro study all samples were put into direct contact with human chondrocyte CHON-001 cells and human osteosarcoma MG-63 cells. Their viability was analysed after 72 h in culture. Moreover, the cell morphology and cell area in contact with CNFs was observed by means of fluorescence microscopy. The obtained results show great potential for the modification of CNFs with polymer, ceramic and carbon modifiers, which do not change the fiber form of the substrate but significantly affect their surface and volume properties. Preliminary biological studies have shown that the type of modification of CNFs affects either the rate of increase in the number of cells or the degree of spreading in relation to the unmodified sample. More hydrophilic and low electrically conductive samples such as CNF_ox and CNF_NaH significantly increase cell proliferation, while other GO and SiOC modified samples have an effect on cell adhesion and thus cell spreading. From the point of view of further research and the possibility of combining the electrical properties of modified CNF scaffolds with electrical stimulation, where these scaffolds would be able to transport electrical signals to cells and thus affect cell adhesion, spreading, and consequently tissue regeneration, samples CNF_GO and CNF_SiOC would be the most desirable.
The aim of the study was to manufacture poly(lactic acid)- (PLA-) based nanofibrous nonwovens that were modified using two types of modifiers, namely, gelatin- (GEL-) based nanofibres and carbon ...nanotubes (CNT). Hybrid nonwovens consisting of PLA and GEL nanofibres (PLA/GEL), as well as CNT-modified PLA nanofibres with GEL nanofibres (PLA + CNT/GEL), in the form of mats, were manufactured using concurrent-electrospinning technique (co-ES). The ability of such hybrid structures as potential scaffolds for tissue engineering was studied. Both types of hybrid samples and one-component PLA and CNTs-modified PLA mats were investigated using scanning electron microscopy (SEM), water contact angle measurements, and biological and mechanical tests. The morphology, microstructure, and selected properties of the materials were analyzed. Biocompatibility and bioactivity in contact with normal human osteoblasts (NHOst) were studied. The coelectrospun PLA and GEL nanofibres retained their structures in hybrid samples. Both types of hybrid nonwovens were not cytotoxic and showed better osteoinductivity in comparison to scaffolds made from pure PLA. These samples also showed significantly reduced hydrophobicity compared to one-component PLA nonwovens. The CNT-contained PLA nanofibres improved mechanical properties of hybrid samples and such a 3D system appears to be interesting for potential application as a tissue engineering scaffold.
Four technologies of clear and cloudy juice production according to typical Polish and French procedures were investigated with six apple cultivars. Clear juices were produced using technologies ...similar to those used by the processing industry, while cloudy juices were processed according to simple protocols used in small-scale processing. In order to best evaluate the effects of the processing technology and cultivar on juice quality, the production of juices was carried out both in Poland and France on the same raw material. The technology, unlike the cultivar, did not affect the soluble solids content of the juice, or the levels of most of the sugars, malic acid or potassium. However, the antioxidant activity measured by the ABTS+ method and the levels of monomeric phenolics and procyanidins strongly depended on the apple cultivar and production technology. For cloudy juices, the selection of appropriate cultivars and production without centrifugation are the key to substantially increasing the amounts of healthy compounds in apple juice.
•Quality of apple juice strongly depends on processing technology.•Selection of cultivars is a key factor for the production of juices rich in phenolic compounds.•Sedimentation rather than centrifugation preserves antioxidants in juice.
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