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Significance Motile microorganisms commonly live in porous media comprising microhabitats filled with interfaces of complex shape. On such small scales, the interactions with these interfaces, rather than external gradients, dominate their motion in the search for favorable living conditions. We demonstrate with experiments and theory that the geometry of confining interfaces shapes the topology of the most likely, average trajectory, leading to directed fluxes of probability that are not exclusively localized at the near-wall region. Employing this principle allows us to actively shape a microbe’s average direction of movement, which could be of use in the design of topological transport mechanisms for microfluidic environments., When the motion of a motile cell is observed closely, it appears erratic, and yet the combination of nonequilibrium forces and surfaces can produce striking examples of organization in microbial systems. While most of our current understanding is based on bulk systems or idealized geometries, it remains elusive how and at which length scale self-organization emerges in complex geometries. Here, using experiments and analytical and numerical calculations, we study the motion of motile cells under controlled microfluidic conditions and demonstrate that probability flux loops organize active motion, even at the level of a single cell exploring an isolated compartment of nontrivial geometry. By accounting for the interplay of activity and interfacial forces, we find that the boundary’s curvature determines the nonequilibrium probability fluxes of the motion. We theoretically predict a universal relation between fluxes and global geometric properties that is directly confirmed by experiments. Our findings open the possibility to decipher the most probable trajectories of motile cells and may enable the design of geometries guiding their time-averaged motion.

The article substantiates the problem of forming baby economy as a factor of national economic development in the global environment. The main baby economy evolution directions as a component of the nanoeconomic system are formulated in the course of research. In addition, Ukraine’s baby economy subsystem, particularly the practice of growing up, socialization and relationship process, is analysed. It has been revealed how little people in this country can influence the course of economic development. The factor analysis is conducted on baby economy factors’ impact on GDP per capita which determines that our GDP manufacturing does not actively depend on the performance of baby economy. This dependence is 0.57. Therefore, it is necessary to introduce the levers of deploying baby economy processes in Ukraine’s economic environment. Furthermore, it has been estimated that the number of people with higher education is gradually increasing as well as the number of foreign students that results in attractiveness of Ukraine’s higher education. As a result of research, the conclusions are based on the necessity of updating baby economy and the beginning of the national economic system development, taking into account the formation of common approaches to education and upbringing. World experience shows that if the economic behaviour of a child is developed by the appropriate education, the level of national economy adaptation to the global environment becomes a decisive issue.Keywords: baby economy, nanoeconomics, human economy, nanotechnology economy, growing up, socialization, kinship, factor analysis. References1. Бажал Ю. Інформаційна економіка. http:// www.ekmair.ukma.edu.ua/bitstream/handle/123456789/2430/Bazhal_Informatsiyna_economica.pdf [Bazhal Yu. information economy. http: //www.ekmair.ukma.edu.ua/bitstream/handle/123456789/2430/Bazhal_Informatsiyna_economica.pdf]2. Балабанов В., Балабанов И. Нанотехнологии. Правда и вымысел. - М.: ЭКСМО, 2017. – 530с. [Balabanov IV, Balabanov I. Nanotechnology. True and fantasy. - M .: Eksmo, 2017. – 530 p.]3. Борисенко В.К. Весільні звичаї та обряди на Україні. К., 1988. [Borisenko VK Wedding customs and rituals in Ukraine. K., 1988.]4. Вовк Хв. Студії з української етнографії та антропології. К., 1995.[Vovk Hv. Studies in Ukrainian Ethnography and anthropology. K., 1995.]5. Годована Т.Л. Формування економічного мислення молодших школярів [Електронний ресурс] / Т.Л. Годована. – Режим доступу: http://www.klasnaocinka.com.ua/uk/article/formuvanna-ekonomichnogo-myslennia-molodshikh-shk.html [Hodovana T.L. Formation of economic thinking younger students [electronic resource] / T.L. Hodovana. - Access mode:http://www.klasnaocinka.com.ua/uk/article/formuvanna-ekonomichnogo-myslennia-molodshikh-shk.html]6. Грішнова О.А. Ефективність інвестицій в людський капітал в Україні: збірник матеріалів міжнародної науково-практичної конференції «Проблеми розвитку ринку праці та поліпшення зайнятості населення в умовах трансформації економіки України», (20-21 листопада 2003 року) / О.А. Грішнова. – Луганськ: Східноук. нац. університет ім. В. Даля, 2003. – С. 13 [Grishnova O.A. The efficiency of investment in human capital in Ukraine: Proceedings of the international scientific conference "Problems of the labor market and improve employment in the economic transformation of Ukraine" (20-21 November 2003) / A.A. Grishnova. - Lugansk: Shidnouk. nat. University. Dal, 2003. - S. 13]

This pre-specified analysis of DAPA-CKD assessed the impact of sodium-glucose cotransporter 2 inhibition on abrupt declines in kidney function in high-risk patients based on having chronic kidney disease (CKD) and substantial albuminuria. DAPA-CKD was a randomized, double-blind, placebo-controlled trial that had a median follow-up of 2.4 years. Adults with CKD (urinary albumin-to-creatinine ratio 200-5000 mg/g and estimated glomerular filtration rate 25-75 mL/min/1.73m2) were randomized to dapagliflozin 10 mg/day matched to placebo (2152 individuals each). An abrupt decline in kidney function was defined as a pre-specified endpoint of doubling of serum creatinine between two subsequent study visits. We also assessed a post-hoc analysis of investigator-reported acute kidney injury-related serious adverse events. Doubling of serum creatinine between two subsequent visits (median time-interval 100 days) occurred in 63 (2.9%) and 91 (4.2%) participants in the dapagliflozin and placebo groups, respectively (hazard ratio 0.68 [95% confidence interval 0.49, 0.94]). Accounting for the competing risk of mortality did not alter our findings. There was no heterogeneity in the effect of dapagliflozin on abrupt declines in kidney function based on baseline subgroups. Acute kidney injury-related serious adverse events were not significantly different and occurred in 52 (2.5%) and 69 (3.2%) participants in the dapagliflozin and placebo groups, respectively (0.77 [0.54, 1.10]). Thus, in patients with CKD and substantial albuminuria, dapagliflozin reduced the risk of abrupt declines in kidney function. HJLH and DC are co-primary authors. The DAPA-CKD Trial Committees and Investigators are listed in the Appendix.

laboratory, pilot and production tests were carried out aimed at the use of powder clinoptilolite jointly with aluminum sulfate to improve the quality of purification of the Dnieper river water. The article showed the advantages of a combined use of these reagents: higher degree of purification, lower consumption of regents, and smaller volume of deposits. The research has begun to obtain composite coagulant by treating with hot sulfuric acid of clinoptilolite and aluminum hydroxide. First research has been conducted of water coagulation under laboratory conditions using composite coagulant and its efficiency was demonstrated.

Characteristics of high and nano- technologies of global markets are discovered in the article. Exactly conditions of patenting of nano-technologies are defined in the world and in corresponding agencies of USA. Factors of publication of nano-articles in international editions and their quantity per million of inhabitants in different countries of the world are outlined. Chief states-producers of nano-knowledges are USA, Japan, Chine and Singapore. Latter is key if the field of expenditure per capita and in a sphere of implementation of data in production. Participation of R&D in increase of GDP is essential for this country. Peculiarity of scientific-technical policy and support of R&D organizations are the factors, which can be used in Ukrainian realities.

Structure functions, as measured in lepton-nucleon scattering, have proven to be very useful in studying the partonic dynamics within the nucleon. However, it is experimentally difficult to separately determine the longitudinal and transverse structure functions, and consequently there are substantially less data available in particular for the longitudinal structure function. Here, we present separated structure functions for hydrogen and deuterium at low four-momentum transfer squared, Q2

We present results on the effect of extension and compression on liquid crystal filaments formed in the B7 phase of bent-core mesogens. There are three distinct temperature regimes in which substantially different structures may form along the filament. The formation of these structures also depends on the velocity at which the filament is extended or compressed.

The formation of flexoelectric stripe patterns (flexodomains) was studied under the influence of external electric and magnetic fields in a nematic liquid crystal. The critical voltage and wavevector of flexodomains were investigated in different geometries by both experiments and simulations. It is demonstrated that upon altering the orientation of the magnetic field with respect to the director, the critical voltage and wavenumber behave substantially differently. In the geometry of the twist Freedericksz transition, a non-monotonic behavior as a function of the magnetic field was found.

We investigate the stability and structure of freely suspended filaments of columnar liquid crystal phases. In the hexagonal columnar phase, filaments with aspect ratios of the order of 20:1 and more can be formed. They can be cooled into a low-temperature body-centred orthorhombic columnar phase without breaking. The slow optic axis is perpendicular to the filament axis and the materials are negatively birefringent in the high-temperature phase. At the transition into the low-temperature phase, the sign of the birefringence is inverted. Within the lifetime of the filaments, three regimes can be distinguished. First, the filaments thin exponentially over a period of about 2 hours. Thereby, the axial alignment improves and the filaments adopt a cylindrical geometry. These cylindrical filaments can persist quasi-stationary for several hours. Fluctuations finally lead to slight inhomogeneities in the filament diameter. This causes Laplace pressure gradients and induces an axial redistribution of material, an...

The article gives a simplified model of water deironization on a filtering medium from natural clinoptilolite based on the results of pilot research and industrial tests. Advantages and disadvantages of the model were found. The possibilities of using this model have been shown in optimization of the water demanganization on natural modified clinoptilolite.

The recoil process of free-standing liquid crystal filaments is investigated experimentally and theoretically. We focus on two aspects, the contraction speed of the filament and a spontaneously formed undulation instability. At the moment of rupture, the filaments buckle similarly to the classical Euler buckling of elastic rods. The tip velocity decays with decreasing filament length. The wavelength of buckling affinely decreases with the retracting filament tip. The energy gain related to the decrease of the total length and surface area of the filaments is mainly dissipated by layer rearrangements during thickening of the fibre. A flow back into the meniscus is relevant only in the final stage of the recoil process. We introduce a model for the quantitative description of the filament retraction speed. The dynamics of this recoil behaviour may find relevance as a model for biology-related filaments.

We demonstrate an unusually strong magneto-optical response of elongated plate-shaped pigment particles in magnetic fields ranging from 0 to 25 T. In a weak field, the particles align perpendicular to the field and the dispersions exhibit the Cotton–Mouton effect. In a strong magnetic field, the magneto-optical behaviour is nonlinear and cannot be explained by a simple model of non-interacting diamagnetic rods in a thermal equilibrium. We also demonstrate that the addition of a small amount of magnetic particles results in a complex magneto-optical response, where the particles align parallel to a weak magnetic field and perpendicular to a strong one.

Microorganisms, such as bacteria and microalgae, often live in habitats consisting of a liquid phase and a plethora of interfaces. The precise ways in which these motile microbes behave in their confined environment remain unclear. Using experiments, Brownian dynamics simulations, and analytical theory, we study the motility of a single Chlamydomonas microalga in an isolated microhabitat with controlled geometric properties. We demonstrate how the geometry of the habitat controls the cell's navigation in confinement. The probability of finding the cell swimming near the boundary scales linearly with the wall curvature, as seen for both circular and elliptical chambers. The theory, utilizing an asymmetric dumbbell model of the cell and steric wall interactions, captures this curvature-guided navigation quantitatively with no free parameters., Comment: 9 pages, 5 figures, revised text

We have assessed, by means of the methods of statistics, the compliance of the treatment facilities of the Dnieper waterworks in Kiev with the state-of-the-art in the quality the Dnieper River water and, in the first place, with that of the organic component, which determines its color.

Laboratory experiments, modeling compaction of sediments building up in sedimentation tanks of water stations under the influence of a GKZh-11 hydrophobizing liquid, the solution of polyhexamethylene guanidine (Aquaton), aluminum sulfate, were carried out. We have determined optimal doses of reagents. It has been shown that the greatest effect of compacting of sediments (21–23%) is achieved by the use of a GKZh-11 hydrophobizing agent and also with a joint action of the hydrophobizing agent and aluminum sulfate (13–18%). The obtained data present a practical interest when developing the technology of treating sediments of washing waters of the sedimentation tanks and filters of water-treatment facilities.

Quality-control dosimetry is important to the routine operation of a radiation processing facility. For many applications this dosimetry must be traceable to a national primary standard. After irradiation at an industrial facility, National Institute of Standards and Technology (NIST)-supplied transfer dosimeters are certified by measurement and dose interpolation from the NIST calibration curve. However, prior to computing the absorbed dose the dosimeter response must be adjusted for the temperature difference between irradiation temperature for the alanine system calibration and the irradiation temperature for the industrial process. For most industrial applications, the temperature is not controlled and varies during the irradiation process. The alanine dosimeter response has a dependence on irradiation temperature, which is compensated for by applying a correction factor to the dosimeter response to compute the absorbed dose. Moreover, there is no consensus protocol to estimate the irradiation temperature and apply this correction. This work approximates industrial temperature profiles using a 60 Co source with a temperature-controlled irradiation chamber, and then compares the relative effectiveness of commonly used industrial methods to correct for irradiation temperature influence on the alanine dosimeter response.

The mechanism of hydrogen-deuterium isotopic exchange was studied in crystalline layer forms of silica (hydrous and cation-substituted SiO2-X2 and SiO2-Y varieties) and alumina (hydrargillite and boehmite) in contact with liquid D2O at temperatures of 20–200°C and saturated vapor pressure. Extensive exchange was observed between adsorbed H2O and D2O molecules via the self-diffusion mechanism in all silica varieties and boehmite at a temperature of 20°C. Deuterium substitution for hydrogen in structural OH groups was observed at 20°C only in the H-form of SiO2-Y (0.7%) and boehmite (1.2 or 17% with molecular deuteration). When the temperature of the hydrothermal treatment of samples was raised up to 200°C, the degree of structural deuterium exchange increased up to 12% (35% with molecular deuteration) in the former case and up to 34% in the latter case. In the former case, the process of isotopic exchange occurred by the nucleophile substitution SNi near surface silicon atoms, and in the latter case, the electrophile substitution ENi in surface OH groups.

Kinetic parameters of mullite formation from oxides in the presence of mineralizers (B2O3 and AlF3) and with a kaolinite additive (20%) are experimentally studied. The degree of completion, the activation energy, and the velocity constants of the mullite-formation reaction in different mixtures are determined. It is demonstrated that AlF3 and kaolinite have the most perceptible accelerating effect.

The properties of hard alloys based on fine-grained hard-alloy mixtures, obtained by coreduction of tungsten oxide with the oxides CoO and Co3O4, are discussed. A linear relation is shown between the strength and the abrasive resistance: the relative abrasive resistance increased and the wear resistance under friction on steel decreased as the strength increased. Fine-grained mixtures obtained by coreduction and carbidization of WO3 and Co3O4 and sintered at 1440–1450°C were found to have the best strength and abrasive resistance. Sintering after homogenizing preannealing enhances the mechanical properties of hard metals.

Correction for ‘Peculiarities of the magneto-optical response in dispersions of anisometric pigment nano-particles’ by A. Eremin et al., RSC Adv., 2016, 6, 80666–80669.

We report on a series of measurements on the microscopic structure and the magneto-optical properties of a calamitic liquid crystalline compound in its nematic phase. Structural studies show the existence of short-range, tilted smectic order consistent with pretransitional effects above an underlying smectic phase. Concomitantly, magneto-optical results exhibit the existence of an optic axis not collinear with the uniaxial director. This apparent biaxial nature is discussed within the context of coupling between the tensor nematic and the smectic order parameters.

Using a magnetic Frederiks transition technique, we measure the temperature and concentration dependences of splay K 1, twist K 2, and bend K 3 elastic constants for the lyotropic chromonic liquid crystal sunset yellow formed through noncovalent reversible aggregation of organic molecules in water. K 1 and K 3 are comparable to each other and are an order of magnitude higher than K 2. At higher concentrations and lower temperatures, K 1 and the ratios K 1/K 3 and K 1/K 2 increase, which is attributed to elongation of self-assembled lyotropic chromonic liquid crystal aggregates, a feature not found in conventional thermotropic and lyotropic liquid crystals formed by covalently bound units of a fixed length.

A large set of cross sections for semi-inclusive electroproduction of charged pions ($��^\pm$) from both proton and deuteron targets was measured. The data are in the deep-inelastic scattering region with invariant mass squared $W^2$ > 4 GeV$^2$ and range in four-momentum transfer squared $2 < Q^2 < 4$ (GeV/c)$^2$, and cover a range in the Bjorken scaling variable 0.2 < x < 0.6. The fractional energy of the pions spans a range 0.3 < z < 1, with small transverse momenta with respect to the virtual-photon direction, $P_t^2 < 0.2$ (GeV/c)$^2$. The invariant mass that goes undetected, $M_x$ or W', is in the nucleon resonance region, W' < 2 GeV. The new data conclusively show the onset of quark-hadron duality in this process, and the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark --> pion production mechanisms. The x, z and $P_t^2$ dependences of several ratios (the ratios of favored-unfavored fragmentation functions, charged pion ratios, deuteron-hydrogen and aluminum-deuteron ratios for $��^+$ and $��^-$) have been studied. The ratios are found to be in good agreement with expectations based upon a high-energy quark-parton model description. We find the azimuthal dependences to be small, as compared to exclusive pion electroproduction, and consistent with theoretical expectations based on tree-level factorization in terms of transverse-momentum-dependent parton distribution and fragmentation functions. In the context of a simple model, the initial transverse momenta of $d$ quarks are found to be slightly smaller than for $u$ quarks, while the transverse momentum width of the favored fragmentation function is about the same as for the unfavored one, and both fragmentation widths are larger than the quark widths.

The differential cross-section for the exclusive process p(e, e0p) has been measured at Q2 5.7 and 7.0 (GeV/c)2, which represents the highest momentum transfer measurement of this to date, significantly higher than the previous highest at Q2 3.6 (GeV/c)2. Data was taken for centre-of-mass energies from threshold to 1.8 GeV, encompassing the S11(1535) resonance, which dominates the pη channel. The total cross section is obtained, from which is extracted the helicity-conserving transition amplitude A1/2, for the production of the S11(1535) resonance. This quantity appears to begin scaling as Q-3, a predicted signal of the dominance of perturbative QCD, within the Q2 range of this measurement. No currently available theoretical predictions can account for the behaviour of this quantity over the full measured range of Q2.

We report on measurements of magnetic-field induced nematic order in the bent-core liquid crystal 4-chlororesorcinol bis[4-(4-$n$-dodecyloxybenzoyloxy) benzoate]. Using the 31 T solenoid at the National High Magnetic Field Laboratory, we have observed, at temperatures less than 1\ifmmode^\circ\else\textdegree\fi{} above the clearing point, a first-order transition to the nematic phase. The critical magnetic field at which this occurs increases with temperature. We discuss these results within the context of both Maier-Saupe and Landau--de Gennes mean-field models for the nematic-isotropic transition. The implications of possible tetrahedratic order are also discussed. To our knowledge, this is the first observation of such a magnetic-field induced transition in a thermotropic liquid crystal; the reasons for which this behavior is now attainable are discussed.

Cross sections for semi-inclusive electroproduction of charged pions ($\pi^{\pm}$) from both proton and deuteron targets were measured for $0.2, Comment: 15 pages, 4 figures. Fit form changed to include Cahn effect Minor revisions. Added one new figure

A large data set of charged-pion electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark-to- pion production mechanisms., Comment: 11 pages, 3 figures, accepted in Phys. Rev. Lett. Tables added

We report results on the high-field magneto-optical response of four aqueous, lyotropic, chromonic liquid crystal formulations in the isotropic phase. Measurements of the field-induced birefringence at temperatures above the isotropic-nematic coexistence region at high magnetic fields reveal qualitative differences in different materials; these differences can be attributed to the nature of aggregation and are discussed within the context of competing aggregation models. Extending these measurements to very high fields and large optical phase differences reveals the presence of an unexpected optical phenomenon: magnetic field-induced circular birefringence, measured in the Voigt geometry, in a system containing no molecularly chiral species. Possible origins of this effect are discussed.

An investigation was carried out into the effect of porosity in the range 2–46% and grain size in the range (5–140)·10−6 m on the mechanical properties of boron carbide. It is shown that the level of mechanical properties of boron carbide produced by hot pressing from powders synthesized from the elements is 1.5 times higher than that of boron carbide produced by other methods. Increasing the porosity of boron carbide to 46% decreases its strength by a factor of six or seven. Increasing the grain size to 140·10−6 m has the same effect. An analysis is made of equations describing the dependence of the mechanical properties of boron carbide on porosity and grain size. The constants of these equations have been determined.

Researches designed to improve the strength properties of hot-pressed parts made of carbide (B4C) involve mainly exploring possible ways of reducing their porosity, preserving their fine-grained structure, and lowering internal stresses in them. In [i, 2] it is shown that compacts produced from B4C powders by hot pressing at temperatures of 2323~ and higher are characterized not only by low porosity but also by a large grain. It has been established [3] that an increase in the grain size of hot-pressed B~C from 5 to 140 Dm lowers its strength to the same extent as does an increase in its porosity from 2 to 46%. Yet published data on the effect of hot-pressing pressure on the structure and properties of boron carbide are apparently nonexistent.

1. A study was made of the densification kinetics of B4C in hot pressing at temperatures in the range 1800–2200°C under a pressure of 225 kgf/cm2. 2. The effects of applied pressure in hot pressing at a temperature of 2100°C were investigated over the range 75–375 kgf/cm2. 3. It is demonstrated that the densification of boron carbide is controlled by a process leading to non-linear creep, whose rate is a function of the square of stress.

This article investigates the kinetics of boron carbide oxidation at high temperatures in air and in water vapor from a chemical and crystallographic viewpoint, identifies the oxidation products as various forms of boron oxides, carbon dioxide, hydrogen, and hydrogen borates, and explores the roles played by porosity, temperature, and boron content on the oxidation of the carbide.

Hot-pressed silicon nitride parts of 1.5–4% porosity containing a 10 wt. % activating addition of MgO are resistant to corrosion by nitric acid at room temperature and by 1% NaOH solution at 100°C under steady-state conditions. The presence of 1–20 wt. % CaF2 added with the aim of improving antifriction properties results in corrosion in nitric acid, obeying the law m2=Kτ, where K ∼ 5.5·10−5· C3 %2/h). The corrosion is due to attack on specimens by hydrofluoric acid forming during the reaction between the CaF2 and HNO3.

A hot-pressed Si3N4-10% MgO material possesses goodoxidation resistance in air at temperatures in the range 1100–1200‡C. When such a material contains an antifriction lubricant (1–20% CaF2), raising the latter's concentration increases its rate of oxidation by decreasing the viscosity of the oxide layer, which facilitates access of oxygen to the specimen surface. At CaF2 contents of more than 5% the material lacks mechanical strength owing to the formation of a thick oxide layer and appearance of cracks.