Search

The major part of commercial prodrugs against Mycobacterium tuberculosis (Mtb) demonstrated a significant inhibitory effect on cell division and inhibition of bacterial growth in vitro. However, further implementation often failed to overcome the compensatory system of interchangeable cascades. This is the most common situation for the compounds, which hit the key enzymes activities involved in all basic stages of the cell cycle. We decided to find more compounds, which could affect a cytoskeleton complex playing important role in sensing the external signals, intracellular transport, and cell division. In general, the bacterial cytoskeleton is crucial for response to the environment and participates in cell-to-cell communication. In turn, filamentous temperature-sensitive Z (FtsZ) protein, a mycobacterial tubulin homolog, is essential for Z-ring formation and further bacteria cell division. We predicted the most preferable binding-sites and conducted a high-throughput virtual screening. Modeling results suggest that some compounds bind in a specific region on the surface Mtb FtsZ, which is absent in human, and other could hit GTPase activity of the FtsZ. Further in vitro studies confirmed that these novel molecules can efficiently bind to these pockets, demonstrating an effect on the polymerization state and kinetics mechanisms. The rescaling of the experiment on the cell line revealed that reported compounds are able to alter the polymerization level of the filamentous and, therefore, prevent mycobacteria reproduction.

The LUXE experiment aims at studying high-field QED in electron-laser and photon-laser interactions, with the 16.5 GeV electron beam of the European XFEL and a laser beam with power of up to 350 TW. The experiment will measure the spectra of electrons and photons in non-linear Compton scattering where production rates in excess of $10^9$ are expected per 1 Hz bunch crossing. At the same time positrons from pair creation in either the two-step trident process or the Breit-Wheeler process will be measured, where the expected rates range from $10^{-3}$ to $10^3$ per bunch crossing, depending on the laser power and focus. These measurements have to be performed in the presence of low-energy high radiation-background. To meet these challenges, for high-rate electron and photon fluxes, the experiment will use Cherenkov radiation detectors, scintillator screens, sapphire sensors as well as lead-glass monitors for backscattering off the beam-dump. A four-layer silicon-pixel tracker and a compact electromagnetic tungsten calorimeter with GaAs sensors will be used to measure the positron spectra. The layout of the experiment and the expected performance under the harsh radiation conditions will be presented.

We propose a novel way to search for feebly interacting massive particles, exploiting two properties of systems involving collisions between high energy electrons and intense laser pulses. The first property is that the electron-intense-laser collision results in a large flux of hard photons, as the laser behaves effectively as a thick medium. The second property is that the emitted photons free-stream inside the laser and thus for them the laser behaves effectively as a very thin medium. Combining these two features implies that the electron-intense-laser collision is an apparatus which can efficiently convert UV electrons to a large flux of hard, co-linear photons. We further propose to direct this unique large and hard flux of photons onto a physical dump which in turn is capable of producing feebly interacting massive particles, in a region of parameters that has never been probed before. We denote this novel apparatus as ``optical dump'' or NPOD (new physics search with optical dump). The proposed LUXE experiment at Eu.XFEL has all the required basic ingredients of the above experimental concept. We discuss how this concept can be realized in practice by adding a detector after the last physical dump of the experiment to reconstruct the two-photon decay product of a new spin-0 particle. We show that even with a relatively short dump, the search can still be background free. Remarkably, even with a 40 TW laser, which corresponds to the initial run, and definitely with a 350 TW laser, of the main run with one year of data taking, LUXE-NPOD will be able to probe uncharted territory of both models of pseudo-scalar and scalar fields, and in particular probe natural of scalar theories for masses above 100 MeV., 10 pages, 4 figures, and 6 pages of supplementary material

The International Large Detector, ILD, is a detector concept which has been developed for the electron-positron collider ILC. The detector has been optimized for precision physics in a range of energies between 90 GeV and 1 TeV. ILD features a high precision, large volume combined silicon and gaseous tracking system, together with a high granularity calorimeter, all inside a 3.5 T solenoidal magnetic field. The paradigm of particle flow has been the guiding principle of the design of ILD. In this document the required performance of the detector, the proposed implementation and the readiness of the different technologies needed for the implementation are discussed. This is done in the framework of the ILC collider proposal, now under consideration in Japan, and includes site specific aspects needed to build and operate the detector at the proposed ILC site in Japan.

The influence of the traffic flows in Kyiv city and harmful substances emissions on the recreational territories was investigated in the paper. A methodology and an integral indicator of the geochemical load on the recreational territories by vehicles and components of their emissions were developed. The integral indicator takes into account (depending on the type of the recreation area and people activity): levels of atmospheric air pollution, contamination of soil and surface waters, as well as bioindicational indicators of the investigated territory. The methods of mathematical statistics, mathematical modeling, field observations, empirical studies and computational experiment have been applied in order to calculate the integral indicator of the geochemical load on the urban recreational territories. In order to determine the pollution of the roadside areas and to predict the ecological status of the studied territories, the semi-empirical equation of turbulent diffusion was used, taking into account the fact that the processes of dispersion and local concentration of harmful impurities in certain parts of the territory are affected by the direction and speed of wind, meteorological conditions, physicochemical properties of pollutants, various processes of their secondary transformation in the environment, as well as the conditions of sedimentation and secondary mechanical settling. On the bases of the solution of this equation, the dispersion fields of hazardous substances that are ingredients of exhaust gases of vehicles (in particular, nitrogen and carbon oxides, fine dust) were built taking into account dangerous wind direction and speed. By the integral indicator, it was determined that the studied roadside recreational territories in many cases are potentially dangerous for human health due to the harmful effects of the motor traffic flows., У роботі досліджено вплив автотранспортних потоків м. Києва та викидів шкідливих речовин на території, які призначені для відпочинку людей. Розроблено методику та запропоновано інтегральний показник геохімічного навантаження на територію рекреаційного призначення з боку автотранспорту та інгредієнтів викидів автотранспортних засобів, який враховує (залежно від виду зони відпочинку й діяльності людей) рівні забруднення атмосферного повітря, ґрунтів і ґрунтових розчинів, поверхневих вод, а також біоіндикаційні показники досліджуваної території. Для розрахунку інтегрального показника застосовано методи математичної статистики, математичного моделювання, натурні спостереження, емпіричні дослідження та обчислювальний експеримент. За інтегральним показником встановлено, що досліджувані придорожні зони відпочинку людей досить часто є потенційно небезпечними для їх здоров’я через шкідливий вплив автотранспортних потоків. За різних погодних і метеорологічних умов спрогнозовано вплив автотранспортних потоків на екологічний стан досліджуваних територій за певної дорожньої ситуації.

CERN 152 pp. (2019). doi:10.23731/CYRM-2019-001, The Compact Linear Collider (CLIC) is a high-energy high-luminosity linear electron-positron collider under development. It is foreseen to be built and operated in three stages, at centre-of-mass energies of 380 GeV, 1.5 TeV and 3 TeV, respectively. It offers a rich physics program including direct searches as well as the probing of new physics through a broad set of precision measurements of Standard Model processes, particularly in the Higgs-boson and top-quark sectors. The precision required for such measurements and the specific conditions imposed by the beam dimensions and time structure put strict requirements on the detector design and technology. This includes low-mass vertexing and tracking systems with small cells, highly granular imaging calorimeters, as well as a precise hit-time resolution and power-pulsed operation for all subsystems. A conceptual design for the CLIC detector system was published in 2012. Since then, ambitious R&D programmes for silicon vertex and tracking detectors, as well as for calorimeters have been pursued within the CLICdp, CALICE and FCAL collaborations, addressing the challenging detector requirements with innovative technologies. This report introduces the experimental environment and detector requirements at CLIC and reviews the current status and future plans for detector technology R&D., Published by CERN

Nowadays, MIS structures based on silicon dioxide films have become the most widely used. However, the desire to reduce the channel length and the nano-scaling in electronics showed, that SiO2 can’t provide the specified MIS devices parameters and characteristics. This is due to the superfine insulator films problem. First of all, this can be solved by replacing SiO2 with another insulator that meets certain requirements. Oxides of transition and rare-earth metals meets almost all of these requirements. However, the principle issue of insulator and semiconductor compatibility remains unsolved in terms of ensure theirs interface quality. Therefore, the researching purpose is to create a general approach to the selection of insulator which is an alternative to silicon dioxide. This insulator must provide a high quality of insulator-semiconductor interface.In MIS structures, the main indicator of semiconductor-insulator interface is its density of the electric charge. Low values of the charge density at the semiconductor-insulator interface are corresponds to high quality of the interface. This is due to the fact that low interface charge density has low affecting on threshold voltage and provide higher its stability. In the first approximation, the surface states density is identically equal to the incomplete bonds density at semiconductor-insulator interface. Therefore, this parameter is selected as the basis of the insulator choosing criterion for a particular semiconductor substrate.It is shown that the classical theory of crystalline lattice (site aspect) can't allow to obtain an analytical expression for the insulator choosing criterion for MIS structures. Therefore, a new form of description of a crystal lattice (intersite aspect) is proposed. Since the crystals differs not only by symmetry but also by the crystallographic orientation of their interface with the vacuum, then an infinite number of solutions about value of incomplete bonds density at the interface correspond to each pair of materials. For obtaining only the one solution by using insulator choosing criterion, a new characteristic parameter of the crystalline substance is introduced - the average bond length. To confirm the practical significance of the average bond length, the relationship between this parameter and electron work function is obtained. The experiment based on literary data of both electron work function and lattice constants was made. The experimental results proves both validity of the relationship and practical significance of the average bond length.On the basis of the intersite aspect and the average bond length, general insulator choosing criterion for MIS structures on certain semiconductor substrate was obtained.For replacement of silicon dioxide in silicon MIS devices, insulator was selected from suitable materials namely oxides of transition and rare-earth metals. The incomplete bonds density at the insulator-silicon interface was calculated for each of these materials. Analysis of the calculation results showed that, in accordance with the insulator choosing criterion, the most promising material is CeO2.The insulator choosing criterion for MIS structures on certain semiconductor substrate is proposed. Its allows, under other equal conditions, to choose the suitable insulator which will provide the least electric charge density at the insulator-semiconductor interface, in comparison with other pretenders. In case of a silicon substrate, such insulator is CeO2. A new characteristic parameter of a crystalline materials is introduced - the average bond length. The analytical expression, which get the relationship between this parameter and the electron work function, is obtained.The obtained results provide an opportunity to make choices insulator for MIS devices based on not only silicon substrates, but also any other semiconductor materials. The proposed insulator choosing criterion can serve as the basis for build new criteria. This ones can help in solving more complicated problems like choosing insulator for MIS devices based on semiconductor substrate with a certain crystallographic orientation.Bibl. 10, Fig. 9., Рассматриваются вопросы общего подхода к поиску диэлектрика для кремниевых МДП-структур в качестве альтернативного диоксиду кремния (SiO2).Показано, что на основе классической теории описания кристаллической решётки (узловой аспект) невозможно получить критерий выбора диэлектрика для МДП-структуры. Поэтому предложен новый –межузловой аспект – описания кристаллической решётки на основе которого получен общий критерий выбора диэлектрика для любой полупроводниковой подложки. Благодаря введению нового характеристического параметра кристаллического вещества – средней длины связи – получено аналитическое выражение для работы выхода электрона из кристалла.Установлено, что наиболее пригодным для кремниевых МДП-структур является диоксид церия CeO2.Библ. 10, рис. 9., Розглядаються питання загального підходу до пошуку діелектрика для кремнієвих МДН-структур як альтернативного діоксиду кремнію (SiO2).Показано, що на основі класичної теорії опису кристалічної решітки (вузловий аспект) неможливо одержати критерій вибору діелектрика для МДН-структур. Тому запропоновано новий – міжвузловий аспект – опису кристалічної решітки, на основі якого одержано загальний критерій вибору діелектрика для будь-якої напівпровідникової підкладки. Завдяки введенню нового характеристичного параметру кристалічної речовини – середньої довжини зв’язку – одержано аналітичний вираз для роботи виходу електрона з кристалу.Встановлено, що найбільш придатним для кремнієвих МДН-структур є діоксид церію CeO2.Бібл. 10, рис. 9.

This paper discusses the use of solid solutions of multicomponent semiconductors for solar energy converted and storage devices in some structural and technological formation options suitable for monolithic integration. The eight-component system under consideration makes it possible to obtain varizon layers from Eg = 6.4 eV (AlN) to Eg = 0.18 eV (InSb) with any set of heterogeneous macro-, micro- and nanosized LED (laser) structures, which allows conduct classical sequential and parallel electronic and optical processing of information, and convert photon fluxes into electric current and accumulate electrical energy in potential wells in the same chip. In this case, the entire spectrum of solar electromagnetic radiation from 200 nm (ultraviolet) to infrared radiation of 12000 nm is used, which is effectively absorbed in the gap layer practically without loss of energy transfer to one or several narrow-band regions specially created by the program in the epitaxy of the varizon layers.The article analyzes examples of the implementation of some heterostructures for converting solar energy into electrical energy, such as AlGaAsSb / GaSb and GaInAsP / InP. The options for optimizing the luminous flux and resistance of contacts in graded-gap construction are considered using the example of an optoelectronic converter. The constructive use of rektenna for energy conversion is considered. The possibilities of using III-nitrides and nanocarbonitrides for energy storage layers of enestors are analyzed. For the formation of optimal nano-templates, as it was established in the course of studies of a simplified model of the process of defect formation, with radii of nano-creations of less critical, dislocation can be achieved with any thickness of the nanotemple. In this case, the curves of the conditionally dislocation-free relief are dominated by three-dimensional limiting effects.Thus, thermodynamic parameters (temperature, pressure) and precursors were experimentally determined in terms of studies of nanocarbide processes in MOСVD epitaxy III-nitrides on nanoparticles of sapphire, in which self-formation of consolidated nanocarbides is realized for layers of energy accumulation on the basis of which, at the present time, the Research Institute of Micro Devices NASU continues research on working out and bringing to the industrial sample the technology of a super capacitor in an enestor chip.These studies and practical developments have demonstrated the great potential of zonistor heterogeneous structures on Iii-nitrides for highly efficient transformation and accumulation of solar radiation energy. The developed gas-phase technology of selective epitaxy makes it possible to obtain defect-free heterostructures, which ensures a high quantum yield of conversion of the whole broad spectrum of solar radiation into electric current and accumulate its energy in one integrated structure. The high quantum yield of the photoelectric effect in nanostructures of solid solutions of the BAlGaInNPAsSb system compensates for technological costs and significantly changes the very paradigm of not only providing energy to electronic functional devices, but also makes it possible in principle to develop a new perspective energy resource for many applications.Ref. 18, fig. 9, tabl. 1., Розроблена нова квантова оптимізація накопичення енергії випромінювання Сонця в енесторах на багатокомпонентних твердих розчинах А3В5: BAlGalnNPAsSb.Розглядаються наступні методи збільшення ефективності сонячних батарей: 1. Накопичення носіїв у глибоких потенціальних ямах і квантових точках; 2. Посилення струму, кероване класичними кремній-транзисторними і квантовими процесорами; 3. Квантові обчислення оптимальних потоків електронів, які утворюють квантово-розмірні куперовские пари, аналогічно високотемпературній надпровідності; 4. Варізонне та гетерогенне розширення спектра поглинання випромінювання Сонця; 5. Бездефектні узгоджувальні темплетні гетерошари в селективній наноепітаксії; 6. Інтеграція випрямлення НВЧ терагерцових сигналів у нанопористих структурах ректен терагерцового діапазону; 7. Накопичення енергії в графенових суперконденсаторах, отриманих у самоорганізованих нанопорах Al2O3; 8. Збільшення поглинання фотонів вертикальними стінками нанопор частково епітаксійно зарощенними основним матеріалом кремнієм або твердими розчинами А3В5.Розроблені технології дають змогу істотно, в 2–5 разів, збільшити енергетичну ефективність сонячних батарей на Si / III-нітридних наноструктурах.Бібл. 18, рис. 9, табл. 1., Разработана новая квантовая оптимизация накопления энергии излучения Солнца в энесторах на многокомпонентных твердых растворах А3В5: BAlGalnNPAsSb.Рассматриваются следующие методы увеличения эффективности солнечных батарей: 1. Накопление носителей в глубоких потенциальных ямах и квантовых точках; 2. Усиление тока, управляемое классическими кремний-транзисторными и квантовыми процессорами; 3. Квантовые вычисления оптимальных потоков электронов, которые образуют квантово-размерные куперовские пары, аналогично высокотемпературной сверхпроводимости; 4. Варизонное и гетерогенное расширение спектра поглощения излучения Солнца; 5. Бездефектные согласующие темплетные гетерослои в селективной наноэпитаксии; 6. Интеграция выпрямления СВЧ терагерцовых сигналов в нанопористых структурах ректен терагерцового диапазона; 7. Накопление энергии в графеновых суперконденсаторах, полученных в самоорганизованных нанопорах Al2O3; 8. Увеличение поглощения фотонов вертикальными стенками нанопор частично эпитаксиально зарощенными основным материалом кремнием или твёрдыми растворами А3В5.Разработанные технологии позволяют существенно, в 2–5 раз, увеличить энергетическую эффективность солнечных батарей на Si/III-нитридных наноструктурах.Библ. 18, рис. 9, табл. 1.

Actuality of the work is determined by the growing anthropogenic pressure on the environment of the urban areas and by the increase of the health problems of the urban population. The aim of the scientific investigation was to analyze and comprehensively estimate the geoecological state of the roadside urban territories, identify the main pollutants and their sources of formation, as well as the factors that have the greatest impact on the distribution of harmful substances and on the degree of the pollution of the territories. Data processing was performed with the help of the statistical methods using Microsoft Office Excel and SPSS Statistics software. Calculations of mean values, measurement errors, two-factor regression analysis, as well as charts and histograms were made with the help of the Microsoft Office Excel. In the article, the influence of the harmful pollutants in the air of the cities on the human health was analyzed; the contribution of the motor transport to the contamination of the urban environment and climate change was determined. The conclusion about the necessity of the complex geoecological analysis of the state of the urban territories and green spaces located near roads and highways was made. Estimation of the acid and salt contamination of the atmospheric precipitation and roadside soils in Kyiv was performed. Correlation dependencies between acid and salt contamination of the roadside areas of the city were found; seasonal dynamics of the pollution was investigated. It was determined that the use of the deicing agents in winter significantly affects the quality of soils and, consequently, affects the state and development of green spaces. The complex index of the geochemical pollution of the studied territories was calculated, Проаналізовано вплив шкідливих домішок в атмосферному повітрі великих міст на здоров’я людей, визначено внесок автотранспорту у забруднення навколишнього міського середовища та у зміни клімату на планеті. Зроблено висновок щодо необхідності комплексного геоекологічного аналізу стану міських територій та зелених насаджень, розташованих поблизу доріг і автомагістралей. Проведена оцінка кислотно-сольового забруднення атмосферних опадів та придорожніх ґрунтів у м. Києві. Встановлено кореляційні залежності між кислотним та сольовим забрудненням придорожньої території великого міста, досліджено сезонну динаміку забруднень. Встановлено, що використання протиожеледних засобів узимку суттєво впливає на якість ґрунтів та, як наслідок, на стан та розвиток зелених насаджень. Розраховано комплексний показник геохімічного забруднення досліджуваних територій

We present a measurement of the cross sections for the associated production of a $W$ boson with at least one heavy quark jet, $b$ or $c$, in proton-antiproton collisions. Data corresponding to an integrated luminosity of 8.7 fb$^{-1}$ recorded with the D0 detector at the Fermilab Tevatron \ppbar Collider at $\sqrt{s}=1.96$ TeV are used to measure the cross sections differentially as a function of the jet transverse momenta in the range 20 to 150 GeV. These results are compared to calculations of perturbative QCD theory as well as predictions from Monte Carlo generators., 10 pages, 8 figures

The 2D azimuth and rapidity structure of the two-particle correlations in relativistic A+A collisions is altered significantly by the presence of sharp inhomogeneities in superdense matter formed in such processes. The causality constraints enforce one to associate the long-range longitudinal correlations observed in a narrow angular interval, the so-called (soft) ridge, with peculiarities of the initial conditions of collision process. This study's objective is to analyze whether multiform initial tubular structures, undergoing the subsequent hydrodynamic evolution and gradual decoupling, can form the soft ridges. Motivated by the flux-tube scenarios, the initial energy density distribution contains the different numbers of high density tube-like boost-invariant inclusions that form a bumpy structure in the transverse plane. The influence of various structures of such initial conditions in the most central A+A events on the collective evolution of matter, resulting spectra, angular particle correlations and vn-coefficients is studied in the framework of the hydrokinetic model (HKM).

The European physical journal / C 77(7), 475 (2017). doi:10.1140/epjc/s10052-017-4968-5, The Compact Linear Collider (CLIC) is an option for a future ${\mathrm{e}^{+}}{\mathrm{e}^{-}} $ collider operating at centre-of-mass energies up to $3\,\text {TeV} $ , providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper is the first comprehensive presentation of the Higgs physics reach of CLIC operating at three energy stages: $\sqrt{s} = 350\,\text {GeV} $ , 1.4 and $3\,\text {TeV} $ . The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung ( ${\mathrm{e}^{+}}{\mathrm{e}^{-}} \rightarrow {\mathrm{Z}} {\mathrm{H}} $ ) and ${\mathrm{W}} {\mathrm{W}} $ -fusion ( ${\mathrm{e}^{+}}{\mathrm{e}^{-}} \rightarrow {\mathrm{H}} {{\nu }}_{\!\mathrm{e}} {\bar{{\nu }}}_{\!\mathrm{e}} $ ), resulting in precise measurements of the production cross sections, the Higgs total decay width $\varGamma _{{\mathrm{H}}}$ , and model-independent determinations of the Higgs couplings. Operation at $\sqrt{s} > 1\,\text {TeV} $ provides high-statistics samples of Higgs bosons produced through ${\mathrm{W}} {\mathrm{W}} $ -fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes ${\mathrm{e}^{+}}{\mathrm{e}^{-}} \rightarrow \mathrm{t} {\bar{\mathrm{t}}} {\mathrm{H}} $ and ${\mathrm{e}^{+}}{\mathrm{e}^{-}} \rightarrow {\mathrm{H}} {\mathrm{H}} {{\nu }}_{\!\mathrm{e}} {\bar{{\nu }}}_{\!\mathrm{e}} $ allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of the precision achievable with Higgs measurements at CLIC and describes the interpretation of these measurements in a global fit., Published by Springer, Berlin

The ILD detector is proposed for an electron-positron collider with collision centre-of-mass energies from 90~\GeV~to about 1~\TeV. It has been developed over the last 10 years by an international team of scientists with the goal to design and eventually propose a fully integrated detector, primarily for the International Linear Collider, ILC. In this report the fundamental ideas and concepts behind the ILD detector are discussed and the technologies needed for the realisation of the detector are reviewed. The document starts with a short review of the science goals of the ILC, and how the goals can be achieved today with the detector technologies at hand. After a discussion of the ILC and the environment in which the experiment will take place, the detector is described in more detail, including the status of the development of the technologies foreseen for each subdetector. The integration of the different sub-systems into an integrated detector is discussed, as is the interface between the detector and the collider. This is followed by a concise summary of the benchmarking which has been performed in order to find an optimal balance between performance and cost. To the end the costing methodology used by ILD is presented, and an updated cost estimate for the detector is presented. The report closes with a summary of the current status and of planned future actions.