Safety and toxicity of carbon nanotubes in our future life

Carbon nanotubes take the form of cylindrical carbon molecules and have novel properties that make them potentially useful in a wide variety of applications in nanotechnology, electronics, optics and other fields of materials science

Prosthetic news

I am sure all of us have heard about prosthetics. It is an artificial device to replace or augment a missing or impaired part of the body. And today I am going to tell you about creations in this area. A generation ago, getting a prosthetic limb fitted usually amounted to a having a heavy, nearly useless hunk of plastic and metal tacked onto your body. But bionic hands just how quickly that‘s all changing. Among the hand‘s more impressive features are its ductile wrist and fingers

Das internationale Autorenliedfestival „Lehesaju Muusika“ in Tartu als spezifische Form der Kulturvermittlung und Analyseobjekt für Mehrsprachigkeitsforschung

The Lehesaju Muusika International Music and Poetry Festival in Tartu as a Specific Form of Cultural Mediation and Object of Analysis for Research on Multilingualism. The paper focuses on the multilingual discourse of the Lehesaju Muusika international music and poetry festival, which takes place annually in Tartu, Estonia. Being an international cultural event organised by ethnic minorities, Lehesaju Muusika represents a unique source of empirical data for research on multilingualism. The festival attracts songwriters and performers of the so-called ‘author song’ or ‘bard song’ not only from Estonia, but also from all over the world. The key feature of this genre is the dominance of the text over the music. The spatial organisation of a concert hall represents a specific power constellation within a microsocial structure. Performing artists have the power to decide in which language they perform and address the multilingual audience, while the audience itself has an indirect effect on this decision. The artist’s dialogue with the audience represents a peculiar discursive entity within the discourse of the festival. Code-switching appears to be one of the inherent characteristics of this discursive entity. The present paper summarises some key features of international music and poetry festivals as multilingual cultural events, focusing on the discourse of the Lehesaju Muusika festival. It offers a brief analysis of the audience’s language profile based on the results of a microsociological case study carried out during the latest festival, in 2019. To illustrate the complexity of the multilingual communication during the festival, three situations of code-switching during the performance of an Estonian native speaker in front of the multilingual audience are described and analysed.         &nbsp

Bmi1 in development and tumorigenesis of the central nervous system

The role of the Polycomb group gene Bmi1 in proliferation control of lymphoid and neuronal progenitors as well as in self-renewal of haematopoietic and neural stem cells has been recently demonstrated. Here we review these recent findings with particular regard to their implications for central nervous system development and tumorigenesi

Effect of multidirectional forging and equal channel angular pressing on ultrafine grain formation in a Cu-Cr-Zr alloy

The microstructure evolution was investigated in a Cu-0.3%Cr -0.5%Zr alloy subjected to large plastic deformation at temperature of 400° C. Two methods of large plastic deformation, i.e., equal channel ang ular pressing (ECAP) and multidirectional forging (MDF) were used. The large plastic deformations resulted in the development of new ultrafine grains. The formation of new ultrafine grains occurred as a result of continuous reaction, i.e., progressive incr ease in the misorientations of deformation subboundaries. The faster kinetics of microstructure evolution was observed during MDF as compared to ECAP. The MDF to a total strain of 4 resulted in the formation of uniform ultrafine grained structure, while ECAP to the same strain led to the heterogeneous microstructure consisting of new ultrafine grains and coarse remnants of original grains . Corresponding area fractions of ultrafine grains comprised 0.23 and 0.59 in the samples subjected to ECAP and MDF, respectivel

Effects of flavonoids on sphingolipid turnover in the toxin-damaged liver and liver cells

<p>Abstract</p> <p>Background</p> <p>The ceramide generation is an early event in the apoptotic response to numerous stimuli including the oxidative stress and ceramide analogs mimic the stress effect and induce apoptosis. Flavonoids of German chamomile are reported to exhibit the hepatoprotective effect. Flavonoids affect sphingolipid metabolism and reduce the elevated ceramide level in the aged liver. In the present paper, the ceramide content and production in the CCl₄- and ethanol-treated liver and hepatocytes as well as the correction of sphingolipid metabolism in the damaged liver using the mixture of German chamomile flavonoids (chamiloflan) or apigenin-7-glucoside (AP7Glu) have been investigated.</p> <p>Results</p> <p>The experiments were performed in either the rat liver or hepatocytes of normal, CCl₄- and ethanol-treated or flavonoid- and toxin plus flavonoid-treated animals. [¹⁴C]palmitic acid and [methyl-¹⁴C-phosphorylcholine]sphingomyelin were used to investigate the sphingolipid turnover. Addition of the CCl₄or ethanol to isolated hepatocyte suspensions caused loss of cell viability and increased the lactate dehydrogenase release from the cells into supernatant and ceramide level in the cells. CCl₄administration to the rats enlarged ceramide mass as well as neutral sphingomyelinase (SMase) activity and reduced ceramide degradation by the neutral ceramidase. Pretreatment of isolated hepatocytes with flavonoids abrogated the CCl₄effects on the cell membrane integrity and normalized the ceramide content. Flavonoid administration to the rats normalized the elevated ceramide content in the damaged liver via neutral SMase inhibition and ceramidase activation.</p> <p>Conclusion</p> <p>The data obtained have demonstrated that flavonoids affect sphingolipid metabolism in the CCl₄- and ethanol-damaged liver and liver cells. Flavonoids normalized activities of key enzymes of sphingolipid turnover (neutral SMase and ceramidase) and ceramide contents in the damaged liver and liver cells, and stabilized the hepatocyte membranes.</p

Using online constructor as a means of increasing motivation to study literature

The aim of this paper - presents the experience in creating a layout of an electronic literature textbook using an online constructor. The “Arctic Robinsonade” plot served as the material for the textbook. The methodological apparatus of the research involves the synthesis of such approaches as hermeneutics and comparative studies. The present investigation is of teaching theory and techniques and digital technologies. The questionnaire surveying method was used to collect the empirical material. Mathematical methods of processing, analysis and interpretation of the pedagogical experiment results were applied in the course of the work. The methods of analyzing differences between independent samples, ranking method, method of testing significance of zero and alternative hypotheses were used for statistic information processing in MS Excel. The results: the capabilities of online constructor Tilda to work on the design of multimedia study aid are determined and described; the model of the chapter in multimedia textbook in native literature is developed; the sections of multimedia study aid are described, the examples of the tasks are given, the efficiency of applying the service of creating websites (online constructor) is established. The developed multimedia product is useful for school teachers and students

Attracting Foreign Investment to Ukraine in the Globalization

Purpose -A characteristic feature of the current state of economic development is the active involvement of foreign direct investment. For Ukraine, this question is relevant because they, above all, are of a scientific-technical progress, additional capital into the country and direct to the international space

Deformation microstructures, strengthening mechanisms, and electrical conductivity in a Cu-Cr-Zr alloy

Cr-0.06%Zr alloy subjected to multiple equal channel angular pressing (ECAP) at temperatures of 473-673 K were investigated. The new ultrafine grains resulted from progressive increase in the misorientations of strain-induced low-angle boundaries during the multiple ECAP process. The development of ultrafine-grained microstructures is considered as a type of continuous dynamic recrystallizatio

Adsorption of inorganic ions from aqueous solutions using mineral sorbent - tripoli

The present research considers the adsorption of H[2]AsO[4] -, CrO[4]{2-}, Ni{2+}, Fe{3+} ions from their aqueous solutions by mineral sorbent - tripoli. Tripoli was characterized by different physico-chemical methods such as X-ray phase analysis, inductively coupled plasma atomic emission spectrometry, method of thermal desorption of nitrogen. Contact time, specific surface area, specific pore volume and surface charge of tripoli have been determined. The effect of tripoli surface area modification by iron (III) oxide-hydroxide on tripoli sorption capacity for the arsenic anions has been investigated. The maximum adsorption was found to occur within 30 minutes of contact time. Different models including the pseudofirst-order kinetic and the pseudo-second-order kinetic equations were used to analyse kinetic data. All the models being considered, it has been stated that the pseudo-second-order kinetic model is the most appropriate to describe the adsorption behaviour of Fe{3+} ions on tripoli. The adsorption has been explained in terms of Langmuir and Freundlich isotherms. Based on values of correlation coefficients, H[2]AsO[4]{-}, CrO[4]{2-}, Ni{2+}, Fe{3+} sorption isotherm data were better fitted by Langmuir model. It has been detected that the modification of mineral sorbent (tripoli) leads to the increase in H[2]AsO[4]{-} adsorbing capacity of tripoli. In general, the results indicated that tripoli can be an efficient low-cost sorbent for removing H[2]AsO[4]{-}, Ni{2+}, Fe{3+} ions from aqueous solutions