Optical transitions and nature of Stokes shift in spherical CdS quantum dots

We study the structure of the energy spectra along with the character of the states participating in optical transitions in colloidal CdS quantum dots (QDs) using the {\sl ab initio} accuracy charge patching method combined with the %pseudopotential based folded spectrum calculations of electronic structure of thousand-atom nanostructures. In particular, attention is paid to the nature of the large resonant Stokes shift observed in CdS quantum dots. We find that the top of the valence band state is bright, in contrast with the results of numerous {\bf k$\cdot$p} calculations, and determine the limits of applicability of the {\bf k$\cdot$p} approach. The calculated electron-hole exchange splitting suggests the spin-forbidden valence state may explain the nature of the ``dark exciton'' in CdS quantum dots.Comment: 5 pages, 4 figure

Concomitant use of statins and s-(2-boron-ethyl)-l-cysteine arginase inhibitor to correct endotoxin-induced endothelial dysfunction

The concomitant use of non-selective S-(2-boron-ethyl)-L-cysteine (BEC) arginase inhibitor with simvastatin, atorvastatin, rosuvastatin and nanoparticulated rosuvastatin on the background of endotoxin-induced disorder modeling by Staphylococcus aureus (strain 13407) injection under the skin – 60 billions of microbial bodies – exhibits an endothelium- and cardioprotective action which is evident as endothelial dysfunction factor (EDF) increase prevention, adrenoreactivity, maintenance of myocardial reserve, and normalization of biochemical markers (total NO, expression of eNOS, C-reactive protein, IL-6, tumor necrosis factor

Analysis of revenues dynamics to the pension fund of Ukraine

У статті проаналізовано динаміку надходжень до Пенсійного фонду України. Зроблено оцінку стійкості та ефективності пенсійної системи. Значну увагу приділено різним чинникам дефіциту пенсійного фонду, таким як: низька ставка внеску, невелика кількість внесків та неповна заробітна плата. Зроблено порівняння пенсійних надходжень та витрат у різних країнах світу. Показано взаємозв’язок між коефіцієнтом залежності від старості та пенсійними витратами у різних країнах світу. Особлива увага приділена демографічній проблемі пенсійної системи. Державні пенсійні видатки розподілено на чотири ключові елементи, такі як: коефіцієнт заміщення, коефіцієнт покриття, коефіцієнт залежності від старості та зворотне співвідношення робочої сили. Розраховано розмір додаткового річного доходу пенсійного фонду. Проаналізовано динаміку витрат на пенсійне забезпечення у відсотках від ВВП. Досліджено операції пенсійного фонду України за період з 2012 по 2017 рік. Показано роль трансфертів із державного бюджету по відношенню до пенсійного фонду. Визначено головні фактори, які ускладнюють проведення реформи у сфері пенсійного забезпечення, зокрема: складна демографічна ситуація, високий рівень тінізації економіки, розбалансованість бюджету та політичний популізм. Підкреслено необхідність коригування пенсійної політики з метою виведення пенсійної системи України на стабільний рівень. Запропоновано шляхи зі збільшення надходжень до пенсійного фонду України та зменшення його дефіциту. Рекомендовано основні етапи реформування пенсійної системи України, якими є оптимізація розміру трудових і соціальних пенсій, розробка схем обов’язкових пенсійних внесків працюючого населення та внесення добровільних пенсійних заощаджень населення до недержавних пенсійних фондів.The article analyzes of revenues dynamics to the Pension Fund of Ukraine. An assessment of the pension system sustainability and effectiveness is made. Considerable attention is paid to various factors of the Pension Fund deficit, such as: a low contribution rate, a small number of contributions and part-time wages. Comparison of pension revenues and expenses in different countries of the world is made. The relationship between the coefficient of dependence on old age and pension expenses in different countries of the world is shown. Particular attention is paid to the demographic problem of the pension system. Government pension expenditures are divided into four key elements, such as: replacement rate, coverage ratio, age dependency ratio and inverse labor ratio. The amount of additional annual income of the pension fund is calculated. The dynamics of expenditures on pensions as a percentage of GDP is analyzed. The operations of the Pension Fund of Ukraine for the period from 2012 to 2017 are investigated. The essence of transfers from the state budget to the pension fund is revealed. The ways of increasing revenues to the pension fund of Ukraine and reducing its deficit are proposed in order to reach a stable level of pension system of Ukraine. The necessity of pension policy adjusting with aim of the pension system of Ukraine bringing to a stable level was emphasized. The main factors, which make reform difficult in the pension security sphere, are defined, in particular: the difficult demographic situation, the high level of shadow economy, imbalance of budget and political populism. The ways to increase revenues to the Pension Fund of Ukraine and reduction its deficit are proposed. The main stages of Ukrainian pension system reforming, which are optimization of labor and social pension’s size, compulsory pension contributions of working population schemes development and voluntary pension savings of population in non-state pension funds introduction, are recommended

Vertical farming: the future of food

In 30 years, 6.5 billion people will live in megacities (about twice as much as today), and to feed such population will be a huge problem. As humanity grows larger, space continues becoming a crucial issue. So, things like houses, interior design, and even garden are becoming more and more vertical. But we are starting to have a large version of gardens, farms. While the field and the greenhouse take their place, this alternative retains it. Vertical farming is the cultivation of products in vertically laid layers

Self‐Assembled Monolayers of Carbohydrate Derivatives on Gold Surfaces

Self‐assembled monolayers (SAMs) presenting carbohydrates (glycans) have been widely prepared on gold surfaces to mimic the carbohydrate surfaces that are involved in molecular recognition phenomena in living cells. The binding affinity of carbohydrate immbolized on SAM surfaces to various carbohydrate‐binding proteins (such as lectins) can be studied by optical, electrochemical, piezoelectrical and thermal sensing techniques. The lectins present on the surface of pathogens (e.g., bacteria or viruses) can be used as targets for capturing onto carbohydrates immobilized on SAM surfaces. The immobilized carbohydrates can also be used for detecting different types of disease biomarkers present in bodily fluids. Synergistic properties of carbohydrate SAMs and gold nanoparticles can be used for vaccine preparation and drug delivery. By studying different types of glycans, their properties, and the behavior toward recognition of specific pathogens and biomarkers, we can develop not only new therapeutics but also enhance the diagnostic strategies of various diseases. In this chapter, we discuss carbohydrate‐terminated SAMs and their common preparation strategies. Next, we focus on roles of different components of SAMs, characterization techniques, and applications

The impact of optical radiation of femtosecond duration on human glial cells

The paper presents the results of the studies of influence of optical radiation with wavelengths of 520 and 780 nm on human glial cells (U251) at the range of exposure times ∼ 1-15 min. It was found that after the first minute of irradiation at the wavelength of 780 nm, the relative number of apoptotic cells significantly increased. The result corroborates the concept of biological hazard of optical radiation for tumor cells, and suggests that the approach has a great potential in clinical application for the treatment of human glioma

Structure and Applications of Gold in Nanoporous Form

Nanoporous gold (np-Au) has many interesting and useful properties that make it a material of interest for use in many technological applications. Its biocompatible nature and ability to serve as a support for self-assembled monolayers of alkanethiols and their derivative make it a suitable support for the immobilization of carbohydrates, enzymes, proteins, and DNA. Its chemically inert, physically robust and conductive high-surface area makes it useful for the design of electrochemistry-based chemical/bio-sensors and reactors. Furthermore, it is also used as solid support for organic molecular synthesis and biomolecules separation. Its enhanced optical property has application in design of plasmonics-based sensitive biosensors. In fact, np-Au is one of the few materials that can be used as a transducer for both optical and electrochemical biosensing. Due to the presence of low-coordination surface sites, np-Au shows remarkable catalytic activity for oxidation of molecules like carbon monoxide and methanol. Owing to the importance of np-Au, in this chapter we will highlight different strategies of fabrication of np-Au and its emerging applications based on its unique properties