Thermal Deformations of Crystal Structures in the L-Aspartic Acid/L-Glutamic Acid System and DL-Aspartic Acid

The method of temperature-resolved powder X-ray diffraction (TRPXRD) was used to determine the elevated temperature behavior of L-aspartic acid (L-asp), DL-aspartic acid (DL-asp), L-glutamic acid (L-glu), and an L-asp0.25,L-glu0.75 solid solution. These amino acids were not found to undergo any solid-phase (polymorph) transformations. When heated, they all experienced only thermal deformations. The corresponding parameters of the monoclinic cells of L-asp and DL-asp, and the orthorhombic cells of L-glu and L-asp0.25,L-glu0.75, were calculated for the entire range of studied temperatures (up to 220 °C). The data obtained were used to calculate the parameters of the thermal deformation tensors, and to plot the figures of their thermal expansion coefficients. A correlation between the maximum and minimum values of thermal expansion coefficients and the length, type, direction, and number of hydrogen bonds in the crystal structures of the investigated amino acids was established. The observed negative thermal expansion (contraction) of crystal structures of L-asp and DL-asp along the ac plane can be explained as a result of shear deformations occurring in monoclinic crystals with a non-fixed angle β. The studies were related to the presence of amino acids in various natural and technological processes occurring at different temperatures

Limits of Solid Solutions and Thermal Deformations in the L-Alanine–L-Serine Amino Acid System

The limits of solid solutions and thermal deformations in the L-alanine–L-serine (L-ala–L-ser) amino acid system have been determined. Thirteen amino acid mixtures with various proportions of the components L-ser/L-ala were studied using powder X-ray diffraction techniques. It was found that the regions of solid solutions in the system are rather limited and cover less than 10 mol. % from each component side. The thermal behavior of the components L-ser and L-ala and the composition L-ser/L-ala = 90/10 were studied by temperature-resolved powder X-ray diffraction. The heating of L-ser and L-ala only causes thermal deformations, while two-phase mixtures with the 90/10 L-ser/L-ala ratio form solid solutions at elevated temperatures. Additionally, the parameters of the thermal deformation tensor for L-ser and L-ala were calculated, and the figures of their thermal expansion coefficients were plotted and analyzed. The study conducted is of high applicability, since amino acids are active components of various biological, geological, and technological processes, including those at elevated temperatures, and have numerous applications in life-science industries

ТРАНСПОРТНАЯ ИНФРАСТРУКТУРА ТУРИЗМА

The article deals with the study of transportation infrastructure of tourism that is considered as an object of management. The author proposes intension, classification, definition, and new managerial algorithm, as well as short-term measures for the relevant companies could achieve a sensible effectiveness increase.Представленная в исследовании  транспортная инфраструктура  туризма рассматривается в качестве  объекта управления. Раскрыта  сущность понятия, разработана  классификация, дано определение,  предложены новый алгоритм  в управлении транспортной  инфраструктурой туризма  и краткосрочные меры, необходимые  для повышения эффективности  работы профильных предприятий

Can the onset of orbital cancer be the result of a prosthetic eye?

Lexenteratio orbitae è un intervento deturpante che si pratica in caso di infezioni orbitarie non responsive a terapia medica e in caso di tumori benigni ricorrenti e tumori maligni che insorgono dalle palpebre (carcinoma basocellulare, carcinoma squamocellulare, melanoma maligno della congiuntiva), dalle ghiandole lacrimali (carcinoma adenoideo cistico) o dalle strutture circostanti. In casi estremamente rari luso di protesi oculari dopo lenucleazione può causare linsorgenza di tumori orbitari. In questo articolo riportiamo il caso di un uomo di 54 anni che è stato sottoposto ad enucleazione dellocchio sinistro in seguito a ricorrenti distacchi di retina e che ha sviluppato, solo 30 anni dopo, un carcinoma epidermoidale infiltrante a rapida crescita. Abbiamo esaminato gli articoli in letteratura per valutare la rarità di tale occorrenza, i tempi dinsorgenza in seguito allenucleazione, i trattamenti e i risultati. Il nostro caso illustra il trattamento della patologia ed enfatizza la necessità di un attento esame della cavità orbitaria e della protesi oculare per identificare anche le irregolarità e i primi danni sulla superficie orbitaria anche nei casi in cui lexenteratio orbitae è stata eseguita per patologie benigne. Il nostro caso dimostra che il follow-up a lungo termine è fondamentale perché il tumore può insorgere a lunga distanza dopo lenucleazione

Efficiency of Magnetostatic Protection Using Nanostructured Permalloy Shielding Coatings Depending on Their Microstructure

The effect of microstructure on the efficiency of shielding or shunting of the magnetic fluxby permalloy shields was investigated in the present work. For this purpose, the FeNi shieldingcoatings with different grain structures were obtained using stationary and pulsed electrodeposition.The coatings’ composition, crystal structure, surface microstructure, magnetic domain structure, andshielding efficiency were studied. It has been shown that coatings with 0.2–0.6μm grains have adisordered domain structure. Consequently, a higher value of the shielding efficiency was achieved,but the working range was too limited. The reason for this is probably the hindered movement of thedomain boundaries. Samples with nanosized grains have an ordered two-domain magnetic structurewith a permissible partial transition to a superparamagnetic state in regions with a grain size of lessthan 100 nm. The ordered magnetic structure, the small size of the domain, and the coexistenceof ferromagnetic and superparamagnetic regions, although they reduce the maximum value ofthe shielding efficiency, significantly expand the working range in the nanostructured permalloyshielding coatings. As a result, a dependence between the grain and domain structure and theefficiency of magnetostatic shielding was found

ONLINE-POLL SERVICE EXAMPLES ON THE EXAMPLE OF GOOGLE FORMS AS A MEANS FOR TESTING KNOWLEDGE OF STUDENTS

Today, teachers have the opportunity to freely and appropriately use computer technologies and Internet resources in their professional activities, thereby freeing themselves from laborious and routine work and saving time for creative improvement in various aspects of their professional activities. For example, the procedure for monitoring and evaluating learning outcomes can be implemented using online survey services. This article describes in detail the use of the Google Forms service, which allows you to quickly and free create online tests of any type from standard tests to quizzes, thanks to which a teacher can make the most effective use of school hours and promptly process control results.Сегодня у учителя есть возможность свободно и уместно использовать компьютерные технологии и Интернет-ресурсы в своей профессиональной деятельности, тем самым освободив себя от выполнения трудоемкой и рутинной работы и сэкономив время для творческого совершенствования в разных аспектах профессиональной деятельности. Так, например, процедура контроля и оценивания результатов обучения может быть реализована с помощью сервисов онлайн-опроса. В данной статье подробно описывается применение сервиса Google Форм, который позволяет быстро и бесплатно создавать онлайн-тесты любой типа от стандартных тестов до викторин, благодаря чему учитель может максимально эффективно использовать учебные часы и оперативно обработать результаты контроля

Evidence of the Generation of Isosaccharinic Acids and Their Subsequent Degradation by Local Microbial Consortia within Hyper-Alkaline Contaminated Soils, with Relevance to Intermediate Level Radioactive Waste Disposal

The contamination of surface environments with hydroxide rich wastes leads to the formation of high pH (>11.0) soil profiles. One such site is a legacy lime works at Harpur Hill, Derbyshire where soil profile indicated in-situ pH values up to pH 12. Soil and porewater profiles around the site indicated clear evidence of the presence of the α and β stereoisomers of isosaccharinic acid (ISA) resulting from the anoxic, alkaline degradation of cellulosic material. ISAs are of particular interest with regards to the disposal of cellulosic materials contained within the intermediate level waste (ILW) inventory of the United Kingdom, where they may influence radionuclide mobility via complexation events occurring within a geological disposal facility (GDF) concept. The mixing of uncontaminated soils with the alkaline leachate of the site resulted in ISA generation, where the rate of generation in-situ is likely to be dependent upon the prevailing temperature of the soil. Microbial consortia present in the uncontaminated soil were capable of surviving conditions imposed by the alkaline leachate and demonstrated the ability to utilise ISAs as a carbon source. Leachate-contaminated soil was sub-cultured in a cellulose degradation product driven microcosm operating at pH 11, the consortia present were capable of the degradation of ISAs and the generation of methane from the resultant H2/CO2 produced from fermentation processes. Following microbial community analysis, fermentation processes appear to be predominated by Clostridia from the genus Alkaliphilus sp, with methanogenesis being attributed to Methanobacterium and Methanomassiliicoccus sp. The study is the first to identify the generation of ISA within an anthropogenic environment and advocates the notion that microbial activity within an ILW-GDF is likely to influence the impact of ISAs upon radionuclide migration

Considerations for the Bioanalytical Part of Equivalence Studies of Biosimilar Nadroparin Calcium

According to current regulatory views, a comparative study of the pharmacodynamics (PD) of low molecular weight heparin (LMWH) products and confirmation of their equivalence require comparing three PD markers: the anti-Xa activity, the anti-IIa activity, and the tissue factor pathway inhibitor (TFPI) concentration. The aim of this study was to analyse the features specific to the bioanalytical part of an equivalence study of a nadroparin calcium biosimilar after single subcutaneous administration. Material and methods: the anti-Xa and anti-IIa activity values and TFPI content were determined in human plasma samples obtained after single subcutaneous administration of the test and the reference product in the same dose, using commercially available reagent kits and pre-validated assays. The authors calculated the main PD parameters (surrogate pharmacokinetic markers), namely the maximum activity or concentration (Amax or Cmax), time to maximum activity or concentration (Tmax), area under the activity–time (or concentration–time) curve (AUC ), and half-life period (T1/2), by means of model-independent statistical moment analysis and carried out further statistical testing of the parameters. Results: the anti-Xa activity and TFPI concentration results provided for  the  possibility  of  calculating  and  comparing  the PD parameters (Amax or Cmax, AUC0-24, AUC0-∞, Tmax, T1/2) and estimating the confidence intervals that are necessary to confirm the bioequivalence of the studied products. The anti-IIa activity data had a characteristic pattern of slight fluctuations around one level, which prevented the calculation and comparison of PD parameters. Conclusion: the study identified specific features to consider when planning comparative PD studies of nadroparin calcium products. Firstly, it is feasible to divide samples into two test aliquots (one for anti-Xa and anti-IIa activity determination, the other for TFPI analysis) at the moment of collection in order to perform the analytical step correctly. Secondly, there is no need in full validation for the bioanalytical assays of the anti-Xa and anti-II activity and TFPI content in human plasma validated in the concentration ranges of 0.024–0.182 IU/mL, 0.0069–0.052 IU/mL and 1.56–100 ng/mL, respectively; a confirmation that the active ingredient does not interfere with the analytical procedure is adequate for the purpose. Finally, the data obtained may not allow for calculating PD parameters and comparing confidence intervals for all three markers. The listed considerations may be relevant for other LMWH products as well