139 research outputs found
Scaling of Gene Expression with Transcription-Factor Fugacity
The proteins associated with gene regulation are often shared between multiple pathways simultaneously. By way of contrast, models in regulatory biology often assume these pathways act independently. We demonstrate a framework for calculating the change in gene expression for the interacting case by decoupling repressor occupancy across the cell from the gene of interest by way of a chemical potential. The details of the interacting regulatory architecture are encompassed in an effective concentration, and thus, a single scaling function describes a collection of gene expression data from diverse regulatory situations and collapses it onto a single master curve
Shape-Induced Frustration of Hexagonal Order in Polyhedral Colloids\ud
The effect of a nonspherical particle shape and shape polydispersity on the structure of densely packed hard colloidal particles was studied in real space by confocal microscopy. We show that the first layer at the wall of concentrated size-monodisperse but shape-polydisperse polyhedral colloids exhibits significant deviations from a hexagonal lattice. These deviations are identified as bond-orientational fluctuations which lead to percolating “mismatch lines.” While the shape-induced geometrical frustration of the hexagonal symmetry suppresses translational order, bond-orientational order is clearly retained, indicating a hexaticlike structure of the polyhedral colloid
Символи Степової України: некрополістичні пам’ятки козаччини
Дослідження містить унікальні дані про символи козацьких хрестів – витвори народного кам’янорізного мистецтва, узагальнює матеріал про хрести запорожців. Пласт наведеної інформації стане корисним дослідникам, які вивчають перебіг історичного процесу у часи руйнування Старої
Січі 1709 р. і Нової Січі у 1775р., а також безпосередньо
вітчизняну некрополістику, палеографію, пам’яткознавство, символіку.This review represents greatly informed bulk of rare memorials, examined in the book of I.V. Sapozhnykov «Stone crosses
of steppe Ukraine (XVIII – first half of the XIX) – Odesa: publishing house «Chornomor’ya», 1997. – 165p., ill.: I – XXVI».
The investigation has unique material about zaporozhtch’s
crosses. The bulk of suggested information can be useful for
investigators who study historical processes during elimination
of Staraya Sich (1709) and Novaya Sich (1775), and also for
those ones who study domestic necropolises, paleography,
symbolism and memorial study
Self-assembly of "Mickey Mouse" shaped colloids into tube-like structures: experiments and simulations
The self-assembly of anisotropic patchy particles with triangular shape was
studied by experiments and computer simulations. The colloidal particles were
synthesized in a two-step seeded emulsion polymerization process, and consist
of a central smooth lobe connected to two rough lobes at an angle of
90, resembling the shape of a "Mickey Mouse" head. Due to the
difference in overlap volume, adding an appropriate depletant induces an
attractive interaction between the smooth lobes of the colloids only, while the
two rough lobes act as steric constraints. The essentially planar geometry of
the "Mickey Mouse" particles is a first geometric deviation of dumbbell shaped
patchy particles. This new geometry is expected to form one-dimensional
tube-like structures rather than spherical, essentially zero-dimensional
micelles. At sufficiently strong attractions, we indeed find tube-like
structures with the sticky lobes at the core and the non-sticky lobes pointing
out as steric constraints that limit the growth to one direction, providing the
tubes with a well-defined diameter but variable length both in experiments and
simulations. In the simulations, we found that the internal structure of the
tubular fragments could either be straight or twisted into so-called Bernal
spirals
Формирование приоритетов интенсификации факторов производства угольного предприятия на основе структурно-иерархического анализа
Проведено оцінку взаємного впливу чинників виробництва і пріоритетів їх формування на базі підприємств вугільної галузі на основі структурно-ієрархічного підходу. Обґрунтовано можливості йі умови аналізу багатоваріантності впливів чинників праці і капіталу на зниження трудомісткості і капіталомісткості очисних робіт. Доведено доцільність застосування методу аналізу ієрархій, за допомогою якого побудовано матриці парних порівнянь.
Ключові слова: інтенсифікація чинників виробництва, матриця попарних порівнянь, метод аналізу ієрархій, структурно-ієрархічний метод, чинники виробництва.Проведена оценка взаимного влияния факторов производства и приоритетов их формирования на базе предприятий угольной отрасли на основе структурно-иерархического подхода. Обоснованы возможности и условия анализа многовариантности воздействия факторов труда и капитала на снижение трудоемкости и капиталоемкости очистных работ. Доказана целесообразность применения метода анализа иерархий, с помощью которого построены матрицы парных сравнений.
Ключевые слова: интенсификация факторов производства, матрица попарных сравнений, метод анализа иерархий, структурно-иерархический метод, факторы производства.In new economics which is based on the knowledge system the level and complicity of innovation development of industrial complexenterprise is determined by such deep transformational phenomena as change of structure of technological modes in world economy, change of qualitative and quantitative proportions of production factors and, in particular, intensification of production factors, which is able to solve such actual problem as migration to primary intensive way of development. That is why the purpose of this research is development and improvement of methodological approach to formation of priority variants of production factors intensification on the basis of method of hierarchies analysis. For solution ofthis task the method of hierarchies analysis is usedwhich is systematic procedure for hierarchical expressing the elements determining the essence of any problem.
The assessment of mutual influence of production factors and priorities of their formation by the example of coal industry enterprise on the basis of structural-hierarchic approach is given in the article. On the basis of structural-hierarchic approach the criteriawere formed, which, each in different ways and with different level of intensity, make influence on meaning of coal enterprise factors. There were proved the possibilities and conditions of multipart influence of labor factors and capital on decrease of labor and capital intensity of coal-face works, which will allow giving rise in increasing effectiveness while securing necessary labor safety. Practicability of method of hierarchies analysis, with the help of which the comparison-of-pairs matrix were built, was proved. Investigation conducted allowed choosing the directions of capital investments for the purpose of getting maximum effect.
Keywords: production factors intensification, comparison-of-pairs matrix, method of hierarchies analysis, structural-hierarchic method, production factors
Стратегічні пріоритети подолання демографічної кризи в Україні
We report a computational study on the spontaneous self-assembly of spherical particles into twodimensional crystals. The experimental observation of such structures stabilized by spherical objects appeared paradoxical so far.We implement patchy interactions with the patches point-symmetrically (icosahedral and cubic) arranged on the surface of the particle. In these conditions, preference for self-assembly into sheet-like structures is observed. We explain our findings in terms of the inherent symmetry of the patches and the competition between binding energy and vibrational entropy. The simulation results explain why hollow spherical shells observed in some Keplerate-type polyoxometalates (POM) appear. Our results also provide an explanation for the experimentally observed layer-by-layer growth of apoferritin - a quasi-spherical protein
Predator-Prey Interactions between Droplets Driven by Nonreciprocal Oil Exchange
Chemotactic interactions are ubiquitous in nature and can lead to
nonreciprocal and complex emergent behavior in multibody systems. Here we show
how chemotactic signaling between microscale oil droplets of different
chemistries in micellar surfactant solutions can result in predator-prey-like
chasing interactions. The interactions and dynamic self-organization result
from the net directional, micelle-mediated transport of oil between emulsion
droplets of differing composition and are powered by the free energy of mixing.
The nonreciprocal behavior occurs in a wide variety of oil and surfactant
conditions, and we systematically elucidate chemical design rules for tuning
the interactions between droplets by varying oil and surfactant chemical
structure and concentration. Through integration of experiment and simulation,
we also investigate the active behavior and dynamic reorganization of
multi-droplet clusters. Our findings demonstrate how chemically-minimal systems
can be designed with controllable, non-reciprocal chemotactic interactions to
generate emergent self-organization and collective behaviors reminiscent of
biological systems
Two-Stage Dynamics of In Vivo Bacteriophage Genome Ejection
Biopolymer translocation is a key step in viral infection processes. The transfer of information-encoding genomes allows viruses to reprogram the cell fate of their hosts. Constituting 96% of all known bacterial viruses [A. Fokine and M. G. Rossmann, Molecular architecture of tailed double-stranded DNA phages, Bacteriophage 4, e28281 (2014)], the tailed bacteriophages deliver their DNA into host cells via an “ejection” process, leaving their protein shells outside of the bacteria; a similar scenario occurs for mammalian viruses like herpes, where the DNA genome is ejected into the nucleus of host cells, while the viral capsid remains bound outside to a nuclear-pore complex. In light of previous experimental measurements of in vivo bacteriophage λ ejection, we analyze here the physical processes that give rise to the observed dynamics. We propose that, after an initial phase driven by self-repulsion of DNA in the capsid, the ejection is driven by anomalous diffusion of phage DNA in the crowded bacterial cytoplasm. We expect that this two-step mechanism is general for phages that operate by pressure-driven ejection, and we discuss predictions of our theory to be tested in future experiments
Ethyl cellulose nanoparticles as stabilizers for Pickering emulsions
Pickering emulsions stabilized by ethyl cellulose nanoparticles have recently received –great attention for their remarkable stability and numerous industrial applications. De- spite this, the exact stabilization mechanism of such Pickering emulsions is still not fully understood. Both the stabilization of the emulsion by particle adsorption at the inter- face and through network formation in the continuous phase (leading to a yield stress) have been suggested. In this work we study soybean oil-in-water emulsions stabilized by ethyl cellulose nanoparticles and find, by the use of confocal microscopy and interfa- cial tension measurements, that the main stabilization mechanism of this nanoparticle- stabilized emulsions is the adsorption of the particles at the interface, instead of forming a network in the continuous phase. At the same time, oscillatory rheology measurements reveal that the emulsions exhibit a yield stress well below the random close-packing limit for hard spheres, suggesting short-range interactions between the droplets caused by the presence of the particles at the interface. The presence of the particles at the interface in combination with the observed rheological behavior of an attractive emulsion gives a strong indication for a particle-bridged stabilized emulsions
Інформаційно-аналітичні технології в сфері фінансового контролю державного бюджету
Розглянуто основні особливості використання інформаційно-аналітичних технологій у сфері фінансового контролю державного бюджету. Запропоновано методику побудови моделі предметної області фінансового контролю держбюджету, в основі якої лежіть багатовимірне представлення даних. Використання цієї моделі дозволило з достатнім ступенем деталізації побудувати ядро сучасної інформаційноаналітичної системи.Рассмотрены основные особенности использования информационно-аналитических технологий в сфере финансового контроля государственного бюджета. Предложена методика построения модели предметной области финансового контроля госбюджета, в основе которой лежит многомерное представление данных. Использование этой модели позволило с достаточной степенью детализации построить ядро современной информационно-аналитической системы.Main features of using information-analytical technologies in the sphere of the financial control of the state budget are considered. The methods of building domain models for financial control of the state budget are offered. The domain model is based on the multivariate data model. Using this model allowed to build the kernel of the modern information-analytical system with sufficient granularity
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