Procjena biokemijskih markera u krvnoj plazmi štakora izloženih kroničnoj primjeni mješavine nanočestica metala

The aim of this study was to determine the effects of a specific mixture of metal nanoparticles (Ag, Cu, Fe and MnО2) orally administered to rats, on biochemical blood markers as indicators of chronic toxicity. Animals (Wistar line rats (n=20)) in experimental groups were given a solution of a mixture of metal salts or a mixture of nanoparticles with food for 90 days. On days 15, 30, 60 and 90 of the experiment, five rats from each group were anaesthetised with CO2 and decapitated, and blood samples were collected for biochemical studies and spectrophotometric measurement. The toxic effect of the chronic administration of the mixture at a dose of 4.0 mg/kg of body weight in white rats caused partial immunosuppression expressed as hypoproteinaemia, excessive formation of circulating immune complexes and acute phase serum mucoid proteins (P<0.05), and cytolytic damage to hepatocyte membranes. Levels of enzyme activity (AST, GGT, ALT and AP) were significantly elevated (P<0.05). It has been shown that the origin of the toxic effect is due to oxidative stress, which slowed lipoperoxidation along with the elevation of the level of carboxylated proteins, depleting the antioxidant defence resources of the organism, as seen by a decrease in the level of catalase and total antioxidant activity (P<0.05). No such effects were observed at the dose of 0.3 mg/kg as there were no significant negative impacts on the biomarkers. Based on this data, the biochemical markers studied may be suitable for use in pre-clinical in vivo toxicological assessment of metal nanoparticle-candidates for pharmaceuticals.Cilj je naše studije bio utvrditi učinke mješavine nanočestica određenih metala (Ag, Cu, Fe i MnО2) koje su oralno davane štakorima na biokemijske markere krvi kao indikatore kronične toksičnosti. Životinjama (štakorima soja Wistar (n=20)) je u eksperimentalnim skupinama hranom tijekom 90 dana davana je otopina mješavine metalnih soli ili mješavine nanočestica. Na 15., 60. i 90. dan eksperimenta, pet štakora je iz svake skupine pomoću CO2 anestezirano i dekapitirano te su prikupljeni uzorci krvi za biokemijske studije. Spektrofotometrijska mjerenja su provedena uporabom SHIMADZU UV-1800 instrumenta. Toksični je učinak kronične primjene NPMe mješavine pri dozi od 4,0 mg/kg tjelesne mase u bijelih štakora izazvao djelomičnu imunosupresiju izraženu kao hipoproteinemija, pretjerano formiranje cirkulirajućih imunokompleksa i mukoidne proteine u serumu (P<0,05) akutne faze te citolitičko oštećenje membrana hepatocita. Razine enzima (AST, GGT, ALT i AP aktivnost) su značajno povećane (P<0,05). Dokazano je da je uzrok toksičnog učinka oksidativni stres, koji je usporio lipoperoksidaciju uz povećanje razina karboksiliranih proteina, iscrpljujući antioksidativnu obranu resursa organizma, očitovanu smanjenjem razine katalaze i ukupne antioksidativne aktivnosti (P<0,05). Takvi učinci pri dozi od 0,3 mg/kg nisu zamijećeni, jer nije bilo značajnih negativnih učinaka na biomarkere. Na temelju naših podataka zaključujemo da je proučavane biokemijske markere moguće izabrati kao osnovu za predkliničku toksikološku procjenu obećavajućih metalnih nanočestica - kandidata za in vivo lijekove

Економіка підприємства

У підручнику розглянуто сучасні актуальні процеси розвитку підприємств: правові засади власності, інтелектуальний капітал, мережеві структури, конкурентну політику, трансформацію та реструктуризацію підприємств; проаналізовано інструментарій, що забезпечує порівнянну вартісну оцінку витрат і результатів діяльності; приділено увагу питанням пошуку і реалізації найбільш ефективних напрямів розвитку підприємства в умовах невизначеності. Для викладачів і студентів економічних спеціальностей, для тих, хто вивчає економічні дисципліни на неекономічних спеціальностях, для фахівців і керівників підприємств.В учебнике рассмотрены современные актуальные процессы развития предприятий: правовые основы собственности, интеллектуальный капитал, сетевые структуры, конкурентную политику, трансформацию и реструктуризацию предприятий; проанализированы инструментарий, обеспечивающий сравнимую стоимостную оценку затрат и результатов деятельности; уделено внимание вопросам поиска и реализации наиболее эффективных направлений развития предприятия в условиях неопределенности. Для преподавателей и студентов экономических специальностей, для тех, кто изучает экономические дисциплины на неэкономических специальностях, для специалистов и руководителей предприятий.The textbook considers the modern current processes of enterprise development: legal principles of ownership, intellectual capital, network structures, competition policy, transformation and restructuring of enterprises; comparable cost-benefit analysis; the book focuses on the search and implementation of the most significant areas of enterprise development in conditions of uncertainty. For teachers and students of economic specialties, those who study economic disciplines in non-economic specialties, for professionals and business leaders

Economics vs. ecology - contemporary trends, risks and challenges

It is widely known that the Greek word ‘oikos’ is the common root for the ‘eco’ in both terms “economics” and “ecology”. It is sometimes stated that ecology is the science of nature’s housekeeping, while economics is the science of human housekeeping. That is why the contemporary tension between ecology and economics is looking strange. We have at least two possibly conflicting objectives in our decision making and those are minimizing environmental impact and maximizing economic profits. While during the last century economic and ecological goals were mostly conflicting with each other, nowadays those goals are getting more and more aligned. The target of reaching sustainable development assumes that meeting the needs of the future depends on how well we balance economic and environmental objectives – or needs – when making decisions today. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/1016

Sensitivity analysis in convex quadratic optimization: Simultaneous perturbation of the objective and right-hand-side vectors

In this paper we study the behavior of Convex Quadratic Optimization problems when variation occurs simultaneously in the right-hand side vector of the constraints and in the coefficient vector of the linear term in the objective function. It is proven that the optimal value function is piecewise-quadratic. The concepts of transition point and invariancy interval are generalized to the case of simultaneous perturbation. Criteria for convexity, concavity or linearity of the optimal value function on invariancy intervals are derived. Furthermore, differentiability of the optimal value function is studied, and linear optimization problems are given to calculate the left and right derivatives. An algorithm, that is capable to compute the transition points and optimal partitions on all invariancy intervals, is outlined. We specialize the method to Linear Optimization problems and provide a practical example of simultaneous perturbation parametric quadratic optimization problem from electrical engineering

Cognitive User Interface for Portfolio Optimization

This paper describes the development of a chatbot as a cognitive user interface for portfolio optimization. The financial portfolio optimization chatbot is proposed to provide an easy-to-use interface for portfolio optimization, including a wide range of investment objectives and flexibility to include a variety of constraints representing investment preferences when compared to existing online automated portfolio advisory services. Additionally, the use of a chatbot interface allows investors lacking a background in quantitative finance and optimization to utilize optimization services. The chatbot is capable of extracting investment preferences from natural text inputs, handling these inputs with a backend financial optimization solver, analyzing the results, and communicating the characteristics of the optimized portfolio back to the user. The architecture and design of the chatbot are presented, along with an implementation using the IBM Cloud, SS&amp;C Algorithmics Portfolio Optimizer, and Slack as an example of this approach. The design and implementation using cloud applications provides scalability, potential performance improvements, and could inspire future applications for financial optimization services