Syllabus of the educational discipline "Management of anti-crisis activity of the enterprise" for higher education holders of the "master's" degree who are studying under the educational and professional program "Enterprise Economics" specialty 076 "Entrepreneurship, trade and exchange activity"

This course is focused on the acquisition by students of higher education of complex theoretical knowledge and practical skills in the development of effective management solutions at various stages of the development of crisis processes at the enterprise. The purpose of studying the discipline is the formation of a system of knowledge in the field of anti-crisis management of the enterprise, modern economic thinking in students and, based on the acquired systematized information, the provision of practical skills in the development of the anti-crisis program of the enterprise, taking into account the financial and economic aspects of the justification of anti-crisis decisions. The goals of studying the discipline: familiarization with the anti-crisis management system of the enterprise and the essence of preventive anti-crisis management; mastering the methodology of diagnosing the crisis state of the enterprise; mastering the technologies of implementing anti-crisis management solutions and the methodology of evaluating their effectiveness; obtaining the necessary knowledge regarding anti-crisis monitoring of the state of the enterprise; familiarization with the anti-crisis personnel management system; acquisition of skills in the application of practical tools of anti-crisis management of the enterprise; development of research abilities of students (masters) and formation of skills of independent development and adoption of anti-crisis management decisions. The following teaching methods and technologies are used: presentations, discussions, mini-lectures, case studies, and others

Non-Enzymatic Co3O4 Nanostructure-Based Electrochemical Sensor for H2O2 Detection

This article describes the synthesis of nanostructured cobalt oxide on iron wires and its application for the detection of hydrogen peroxide as working electrode for non-enzymatic electrochemical sensor. Cobalt oxide was obtained by the hydrothermal synthesis method using chloride and acetate anions. The resulting nanostructured coating obtained from the chloride precursor is a uniform homogeneous porous network of long nanofibers assembled into regular honeyсomb-like formations. In the case of an acetate precursor, instead of nanofibers, petal-like nanostructures assembled into honeycomb agglomerates are observed. The structure, surface, and composition of the obtained samples were studied using field-emission scanning electron microscopy along with energy-dispersive spectroscopy and X-ray diffractometry. The resultant nanostructured specimens were utilized to detect H2O2 electrochemically through cyclic voltammetry, differential pulse voltammetry, and i-t measurements. A comparative research has demonstrated that the nanostructures produced from the chloride precursor exhibit greater sensitivity to H2O2 and have a more appropriate morphology for designing a nanostructured sensor. A substantial linear correlation between the peak current and H2O2 concentration within the 20 to 1300 μM range was established. The Co3O4 electrode obtained exhibits a sensitivity of 505.11 μA·mM−1, and the electroactive surface area is calculated to be 4.684 cm2. Assuming a signal-to-noise ratio of 3, the calculated limit of detection is 1.05 μM. According to the interference study, the prevalent interfering agents, such as ascorbic acid, uric acid, NaCl, and glucose, do not influence the electrochemical reaction. The obtained results confirm that this sensor is suitable for working with complex analytes.The actual sample assessment demonstrated a recovery rate exceeding 95 %. --//-- This is an open access article Mizers, V., Gerbreders, V., Krasovska, M., Sledevskis, E., Mihailova, I., Ogurcovs, A., Bulanovs, A. and Gerbreders, A.. "Non-Enzymatic Co3O4 Nanostructure-Based Electrochemical Sensor for H2O2 Detection" Latvian Journal of Physics and Technical Sciences, vol.60, no.6, 2023, pp.63-84. https://doi.org/10.2478/lpts-2023-0037 published under the CC BY-NC-ND 4.0 licence.The research has been supported by ESF Project No. 8.2.2.0/20/I/003 “Strengthening of Professional Competence of Daugavpils University Academic Personnel of Strategic Specialization Branches 3rd Call”. The Institute of Solid State Physics, University of Latvia at the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2

МЕТОДИ УПРАВЛІННЯ МИТНИМИ РИЗИКАМИ В ЗОВНІШНЬОЕКОНОМІЧНІЙ ДІЯЛЬНОСТІ

The article is devoted to the analysis of prospects for the use ofstrategic methods of customs risk management in the foreign economicactivity of enterprises.Ukraine's participation in international organizations, strengtheningforeign economic cooperation, ensuring competitiveness in the world market, raising the country's rating in the world community, implementing international standards requires reforming the modern political, legal, economic, financial, social and other systems of our state. Foreign economic activity today is the most promising area of business. Considering that the pace of production in Ukraine has decreased, foreign economic activity is one of the most profitable activities.As a rule, in the conditions of limited resource and financialopportunities each of the parties of business interests tries to find anopportunity to optimize the expenses and to increase the profit (profit) asmuch as possible. By adopting such rules of the game, businesses findthemselves in a state of uncertainty and are on the verge of the legal field.Based on this, it is difficult to predict the course of events, but a desperate player in the market is trying to take risks in the hope of receiving a decent dividend (profit). This means that the risks have become the focus of attention of economists, lawyers and experts in various fields of knowledge.International trade around the world is a major, accelerating force thataffects the economic development of each country. The State CustomsService of Ukraine protects the economic interests of the state and monitors foreign economic activity, ie trade between countries. In this way, it optimizes the trading conditions of business entities.Цель исследования заключается в определении понятий, что такоериск, анализ риска, каким образом осуществляется управление рискамии определение критериев риска, как могут таможенные органы(таможенные администрации) минимизировать риски.Внешнеэкономическая деятельность на сегодняшний деньпредставляет собой наиболее перспективное направление бизнеса.Учитывая то, что темпы производства в Украине снизились,внешнеэкономическая деятельность является одной из рентабельныхвидов деятельности.Статтю присвячено аналізу перспектив використання стратегічних методів управління митними ризиками в зовнішньоекономічній діяльності підприємств. Участь України в міжнародних організаціях, посилення зовнішньоекономічного співробітництва, забезпечення конкурентоспроможності на світовому ринку, підвищення рейтингу держави у світовій спільноті, впровадження міжнародних стандартів потребує реформування сучасної політичної, правової, економічної, фінансової, соціальної та інших систем нашої держави

Morphology Influence on Wettability and Wetting Dynamics of ZnO Nanostructure Arrays

This study has been supported by internal research grant No. 14-95/2021/10 of Daugavpils University “Development of the Nanostructured Metal Oxide Coatings and Their Application in Optical Sensing for Heavy Metal Detection”.Changes in nanostructure morphology and size may result in very different surface wettability. In this research, the impact of different morphological parameters on the wetting dynamics of ZnO nanostructured layers is studied. Six different morphologies are chosen to determine the specific wetting processes of ZnO nanostructures: nanoneedles, small diameter rods, large diameter rods, nanotubes, nanoplates, and plain thin films. Wetting dynamics is investigated using conventional sessile drop technique and a novel approach based on electrochemical impedance spectroscopy. The results show that the surface of nanostructured ZnO thin films exhibits both hydrophilic and hydrophobic wetting behaviour, depending on nanostructure form, size, and orientation. ZnO nanostructure arrays are a promising platform for electrochemical and optical sensing in aqueous solutions. The full and effective use of the sensor working surface can be ensured only under the condition of complete wetting of the nanostructured layer. Therefore, it is important to take into account the peculiarities of the wetting process of a specific morphology of nanostructures. © 2022 V. Gerbreders et al., published by Sciendo.Institute of Solid State Physics, University of Latvia has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2

Доведення регіоселективності перебігу циклізації 1-етил-3-[4-6,7,8,9-тетрагідро-5Н-[1,2,4]триазоло[4,3-а]азепін-3-іл)феніл]тіосечовини з α-бромкетоном

An important step in creation of potential drugs is to confirm the structure of the compounds synthesized. This requires the use of modern physical and physico-chemical methods of research. Nowadays a promising scientific direction for searching biologically active substances is the study of 2-R-imino-1,3-thiazoline derivatives.Aim. To study regioselectivity of the cyclization reaction of 1-ethyl-3-[4-(6,7,8,9-tetrahydro-5Н-[1,2,4]triazolo[4,3-а]azepin-3-yl)phenyl]thiourea with 2-bromo-1-phenylethanone. Results. The true structure of the interaction product was determined by the methods of 1H NMR spectroscopy and X-ray analysis. Quantum chemical calculations of the electronic structure, geometry and thermodynamic parameters of the initial thiourea three tautomers were given. Activating energy of tautomer 1A belower than 1B one, the state of 1B has modest lower relative energy, consequently tautomer 1A is more credible state. Thus, the conclusion can be made that the reaction will proceed by 1-1A-3A.Experimental part. Quantum chemical calculations of the electronic structure, geometry and thermodynamic parameters of the initial thiourea three tautomers were determined by the density functional theory (DFT) methods using the GAUSSIAN W09 computer program. The effect of the solvent was considered within the framework of polarized continuum model (PCM). Conclusions. Based on the physico-chemical studies and quantum chemical calculations of the reaction cyclization direction the conclusion has been made that the cyclization reaction of 1-ethyl-3-[4-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-а]azepin-3-yl)phenyl]thiourea 1 with 2-bromo-1-phenylethanone 2 is regioselective, and it leads to formation of more thermodynamically advantageous (stable) isomer 3A. Важным этапом создания потенциальных лекарственных средств является подтверждение структуры синтезированных соединений, что требует использования современных физических и физико-химических методов исследования. На сегодня перспективным научным направлением в плане поиска биологически активных веществ является исследование в ряду производных 2-R-имино-1,3-тиазолина.Целью работы является изучение региоселективности реакции циклизации 1-этил-3-[4-(6,7,8,9-тетрагидро-5Н-[1,2,4]триазоло[4,3-а]азепин-3-ил)фенил]тиомочевины с 2-бром-1-фенилэтаноном.Результаты и их обсуждение. Установление истинного строения продукта взаимодействия осуществлено с помощью методов 1Н ЯМР-спектроскопии и рентгеноструктурного анализа. Приведены квантово-химические расчеты электронной структуры, геометрии и термодинамических параметров трех таутомеров исходной тиомочевины. Энергия активации таутомера 1А несколько ниже, состояние 1В имеет незначительно меньшую относительную энергию, следовательно, таутомер 1А является более вероятным. Таким образом, мы можем сделать вывод, что реакция пойдет по пути 1-1А-3А.Экспериментальная часть. Квантово-химические расчеты электронной структуры, геометрии и термодинамических параметров трех таутомеров исходной тиомочевины вычислены методами теории функционала плотности (DFT) с использованием компьютерной программы GAUSSIAN 09W. Учет влияния растворителя осуществлялся в рамках модели поляризуемого континуума (PCM).Выводы. На основе проведенных физико-химических исследований и квантово-химических расчетов направления прохождения реакции конденсации 1-этил-3-[4-6,7,8,9-тетрагидро-5Н-[1,2,4]триазоло[4,3-а]азепин-3-ил)фенил]тиомочевины с 2-бромо-1-фенилэтаноном сделан вывод о ее региоселективности с образованием более термодинамически выгодного изомера 3А.Важливим етапом створення потенційних лікарських засобів є підтвердження структури синтезованих сполук, що потребує використання сучасних фізичних та фізико-хімічних методів дослідження. На сьогодні перспективним науковим напрямком при пошуку біологічно активних речовин є дослідження в ряду похідних 2-R-іміно-1,3-тіазоліну.Метою роботи є вивчення регіоселективності реакції циклізації 1-етил-3-[4-(6,7,8,9-тетрагідро-5Н-[1,2,4]триазоло[4,3-а]азепін-3-іл)феніл]тіосечовини з 2-бромо-1-фенілетаноном. Результати та їх обговорення. Встановлення істинної будови продукту взаємодії здійснено за допомогою методів 1Н ЯМР-спектроскопії та рентгеноструктурного аналізу. Наведені квантово-хімічні розрахунки електронної структури, геометрії і термодинамічних параметрів трьох таутомерів вихідної тіосечовини. Енергія активації таутомеру 1А дещо нижча, стан 1В має незначно нижчу відносну енергію, отже, таутомер 1А є більш ймовірним. Таким чином, ми можемо зробити висновок, що реакція перебігатиме шляхом 1-1А-3А.Експериментальна частина. Квантово-хімічні розрахунки електронної структури, геометрії і термодинамічних параметрів трьох таутомерів вихідної тіосечовини обчислені методами теорії функціоналу густини (DFT) з використанням комп’ютерної програми GAUSSIAN 09W. Облік впливу розчинника здійснювався в рамках моделі континууму, що поляризується (PCM). Висновки. На основі проведених фізико-хімічних досліджень і квантово-хімічних розрахунків напрямку проходження реакції конденсації 1-етил-3-[4-6,7,8,9-тетрагідро-5Н-[1,2,4]триазоло[4,3-а]азепін-3-іл)феніл]тіосечовини з 2-бромо-1-фенілетаноном зроблений висновок про її регіоселективність з утворенням більш термодинамічно вигідного ізомеру 3А.

ОЦІНКА ДИНАМІКИ ЗАГАЛЬНОЇ ФАКТОРНОЇ ПРОДУКТИВНОСТІ СІЛЬСЬКОГО ГОСПОДАРСТВА В УКРАЇНІ

This paper has reviewed the developments in agricultural productivityrelated to Ukrainian conditions, namely in the last two decades. Expandedtreatment of the economic category of productivity, which in addition to labor includes other factors of production, is essential for the economic research. It is important for the agriculture, where the processes of mechanization and automation occur especially fast. The method of multifactor productivity estimation shows which of the factors of production result in an increase or decrease of real agricultural output.The growth have been summarized for Ukrainian Agriculture. The basefor multifactor productivity calculations is the estimation of total factorproductivity. This methodology has been used in international economicdiscussion to determine whether economic growth is extensive or intensive.The approach used is to estimate the ratio of total output to resource input.At the same time, both indicators are estimated not in absolute terms, but using the index approach. We present the estimation of indices of agricultural output and indices of agricultural cost. The graph of dynamics of the level of total factor productivity of Ukrainian Agriculture is based onthese calculations and the downward dynamics of the indicator of totalfactor productivity of agriculture of Ukraine. It reflects the reduction of the effectiveness of the agrarian sector while the volume of production inabsolute terms increases. It highlights the importance of analysis ofefficiency reduction and the research for sources of further economicgrowth in agriculture in Ukraine. Such research will be the subject ofsubsequent publications.Раскрыта важность расширенной трактовки экономическойкатегории производительности с помощью показателя совокупнойфакторной производительности. Для оценки соотношения совокупногопоказателя выпуска продукции с затратами ресурсов использованиндексный подход. Оценены индексы производствасельскохозяйственной продукции и индексы себестоимостисельскохозяйственного производства. Показана динамика уровнясовокупной факторной производительности сельского хозяйства вУкраине. Отражено снижение эффективности аграрного сектора принаращивании объемов производства в абсолютных показателях.Розкрито важливість розширеного трактування економічної категорії продуктивності за допомогою показника загальної факторної продуктивності. Для оцінки співвідношення сукупного показника випуску продукції з витратами ресурсів використано індексний підхід. Оцінено індекси виробництва сільськогосподарської продукції та індекси собівартості сільськогосподарського виробництва. Показано динаміку рівня загальної факторної продуктивності сільського господарства в Україні. Відображено зниження ефективності аграрного сектору при нарощуванні обсягів виробництва в абсолютних показниках

Molecular Dynamics and Quantum Mechanics of RNA: Conformational and Chemical Change We Can Believe In

Structure and dynamics are both critical to RNA’s vital functions in biology. Numerous techniques can elucidate the structural dynamics of RNA, but computational approaches based on experimental data arguably hold the promise of providing the most detail. In this Account, we highlight areas wherein molecular dynamics (MD) and quantum mechanical (QM) techniques are applied to RNA, particularly in relation to complementary experimental studies

Characterization of the Trans Watson-Crick GU Base Pair Located in the Catalytic Core of the Antigenomic HDV Ribozyme

The HDV ribozyme’s folding pathway is, by far, the most complex folding pathway elucidated to date for a small ribozyme. It includes 6 different steps that have been shown to occur before the chemical cleavage. It is likely that other steps remain to be discovered. One of the most critical of these unknown steps is the formation of the trans Watson-Crick GU base pair within loop III. The U23 and G28 nucleotides that form this base pair are perfectly conserved in all natural variants of the HDV ribozyme, and therefore are considered as being part of the signature of HDV-like ribozymes. Both the formation and the transformation of this base pair have been studied mainly by crystal structure and by molecular dynamic simulations. In order to obtain physical support for the formation of this base pair in solution, a set of experiments, including direct mutagenesis, the site-specific substitution of chemical groups, kinetic studies, chemical probing and magnesium-induced cleavage, were performed with the specific goal of characterizing this trans Watson-Crick GU base pair in an antigenomic HDV ribozyme. Both U23 and G28 can be substituted for nucleotides that likely preserve some of the H-bond interactions present before and after the cleavage step. The formation of the more stable trans Watson-Crick base pair is shown to be a post-cleavage event, while a possibly weaker trans Watson-Crick/Hoogsteen interaction seems to form before the cleavage step. The formation of this unusually stable post-cleavage base pair may act as a driving force on the chemical cleavage by favouring the formation of a more stable ground state of the product-ribozyme complex. To our knowledge, this represents the first demonstration of a potential stabilising role of a post-cleavage conformational switch event in a ribozyme-catalyzed reaction

Revision of AMBER Torsional Parameters for RNA Improves Free Energy Predictions for Tetramer Duplexes with GC and iGiC Base Pairs

All-atom force fields are important for predicting thermodynamic, structural, and dynamic properties of RNA. In this paper, results are reported for thermodynamic integration calculations of free energy differences of duplex formation when CG pairs in the RNA duplexes r(CCGG)2, r(GGCC)2, r(GCGC)2, and r(CGCG)2 are replaced by isocytidine–isoguanosine (iCiG) pairs. Agreement with experiment was improved when ε/ζ, α/γ, β, and χ torsional parameters in the AMBER99 force field were revised on the basis of quantum mechanical calculations. The revised force field, AMBER99TOR, brings free energy difference predictions to within 1.3, 1.4, 2.3, and 2.6 kcal/mol at 300 K, respectively, compared to experimental results for the thermodynamic cycles of CCGG → iCiCiGiG, GGCC → iGiGiCiC, GCGC → iGiCiGiC, and CGCG → iCiGiCiG. In contrast, unmodified AMBER99 predictions for GGCC → iGiGiCiC and GCGC → iGiCiGiC differ from experiment by 11.7 and 12.6 kcal/mol, respectively. In order to test the dynamic stability of the above duplexes with AMBER99TOR, four individual 50 ns molecular dynamics (MD) simulations in explicit solvent were run. All except r(CCGG)2 retained A-form conformation for ≥82% of the time. This is consistent with NMR spectra of r(iGiGiCiC)2, which reveal an A-form conformation. In MD simulations, r(CCGG)2 retained A-form conformation 52% of the time, suggesting that its terminal base pairs may fray. The results indicate that revised backbone parameters improve predictions of RNA properties and that comparisons to measured sequence dependent thermodynamics provide useful benchmarks for testing force fields and computational methods

Effects of Restrained Sampling Space and Nonplanar Amino Groups on Free-Energy Predictions for RNA with Imino and Sheared Tandem GA Base Pairs Flanked by GC, CG, iGiC or iCiG Base Pairs

Guanine-adenine (GA) base pairs play important roles in determining the structure, dynamics, and stability of RNA. In RNA internal loops, GA base pairs often occur in tandem arrangements and their structure is context and sequence dependent. Calculations reported here test the thermodynamic integration (TI) approach with the amber99 force field by comparing computational predictions of free energy differences with the free energy differences expected on the basis of NMR determined structures of the RNA motifs (5′-GCGGACGC-3′)2, (5′-GCiGGAiCGC-3′)2, (5′-GGCGAGCC-3′)2, and (5′-GGiCGAiGCC-3′)2. Here, iG and iC denote isoguanosine and isocytidine, which have amino and carbonyl groups transposed relative to guanosine and cytidine. The NMR structures show that the GA base pairs adopt either imino (cis Watson−Crick/Watson−Crick A-G) or sheared (trans Hoogsteen/Sugar edge A-G) conformations depending on the identity and orientation of the adjacent base pair. A new mixing function for the TI method is developed that allows alchemical transitions in which atoms can disappear in both the initial and final states. Unrestrained calculations gave ΔG° values 2−4 kcal/mol different from expectations based on NMR data. Restraining the structures with hydrogen bond restraints did not improve the predictions. Agreement with NMR data was improved by 0.7 to 1.5 kcal/mol, however, when structures were restrained with weak positional restraints to sample around the experimentally determined NMR structures. The amber99 force field was modified to partially include pyramidalization effects of the unpaired amino group of guanosine in imino GA base pairs. This provided little or no improvement in comparisons with experiment. The marginal improvement is observed when the structure has potential cross-strand out-of-plane hydrogen bonding with the G amino group. The calculations using positional restraints and a nonplanar amino group reproduce the signs of ΔG° from the experimental results and are, thus, capable of providing useful qualitative insights complementing the NMR experiments. Decomposition of the terms in the calculations reveals that the dominant terms are from electrostatic and interstrand interactions other than hydrogen bonds in the base pairs. The results suggest that a better description of the backbone is key to reproducing the experimental free energy results with computational free energy predictions