Application of Born series for modeling of Mie-resonant nanostructures

Born series formalism is a widely-used approach to solve a scattering problem in quantum mechanics and optics, including a problem of electromagnetic scattering on the ensembles of Mie-resonant nanoparticles. In the latter case, the Born series formalism can be used when the electromagnetic coupling between nanoparticles is weak. This can be violated near the multipole Mie-resonance of the nanoparticle. In this work, we analyze the applicability of the Born series approach for modeling the resonant optical response of Mie-nanoparticle ensembles and formulate quantitative criteria of Born series convergence and, subsequently, the applicability of this approach

Principles of development of the transport-transit potential of the primorskiy region

Розглянуто сукупність принципів формування транзитного потенціалу приморських регіонів. Обґрунтовано інструментарій ефективного використання пропускних здібностей морських портів на основі обліку підприємницького ефекту і синергії. Обґрунтовано напрямки підвищення національної складової транзитного потенціалу торгових портів.Рассмотрена совокупность принципов формирования транзитного потенциала приморских регионов. Обосновано инструментарий эффективного использования пропускных способностей морских портов на основе учёта предпринимательского эффекта и синергии. Обоснованы направления повышения национальной составляющей транзитного потенциала торговых портов

Light focusing by silicon nanosphere structures under conditions of magnetic dipole and quadrupole resonances

Metalens is a planar device for light focusing. In this work, we design and optimize c-Si nanosphere metalenses working on the magnetic dipole and quadrupole resonances of the c-Si nanoparticle. Resonant optical response of c-Si nanostructures is simulated by the multipole decomposition method along with the zero-order Born approximation. Limitations of this approach are investigated. The obtained results of optimization are verified by simulation via the T-matrix method

Evolutionary and genetic algorithms for design of metadevices working on electric dipole resonance

All-dielectric nanophotonics is a rapidly growing field of modern science. Metasurfaces and other planar devices based on all-dielectric nanoparticles lead to manage the light propagation at the nanoscale. Impressive effects such as perfect absorption, invisibility, chirality effects, negative refraction, light focusing in the area with size smaller than wavelength, nano-lasing etc - can be achieved with all-dielectric technologies. While it is needed to use more and more complicated designs for solution of modern nanophotonics' currents tasks, non-classical methods of optimization become relevant. For example, to design reconfigurable metalenses with an additional degree of freedom such as polarizability or temperature dependence, evolutionary or genetic algorithms show their high applicability. In this work, we show a new approach to design metalenses with evolutionary and genetic algorithms. © 2020 IOP Publishing Ltd

Enrichment of meat products with dietary fibers: a review

ArticleIn recent years, much attention has been paid to the development of food products with properties that can promote well-being and prevent disease. Tested strategies to improve the functional value of meat products through the introduction of dietary fiber are reviewed here. Based on the literature reviewed, the addition of dietary fiber in meat products contributes to the fabrication of products which enhance physiological functions. Furthermore, fibers can be used to improve the quality and yield of meat products

Polarization Switching Between Electric and Magnetic Quasi-Trapped Modes in Bianisotropic All-Dielectric Metasurfaces

A general strategy for the realization of electric and magnetic quasi-trapped modes located at the same spectral position is presented. This strategy's application makes it possible to design metasurfaces allowing switching between the electric and magnetic quasi-trapped modes by changing the polarization of the incident light wave. The developed strategy is based on two stages: the application of the dipole approximation for determining the conditions required for the implementation of trapped modes at certain spectral positions and the creation of the energy channels for their excitation by introducing a weak bianisotropy in nanoparticles. Since excitation of trapped modes results in a concentration of electric and magnetic energies in the metasurface plane, the polarization switching provides possibilities to change and control the localization and distribution of optical energy at the sub-wavelength scale. A practical method for spectral tuning of quasi-trapped modes in metasurfaces composed of nanoparticles with a preselected shape is demonstrated. As an example, the optical properties of a metasurface composed of silicon triangular prisms are analyzed and discussed

Chronobiological approach to study the physiological activity of <i>Candida</i> species

Rythmometric markers can be identified within a day during the study of biological characteristics in order to be used for differential diagnostics of pathogens of different patients’ physical condition. These principles are based on analysis of clinical isolates С. albicans, С. tropicalis and C. krusei allocated from the vaginal microbiota at Candida dysbiosis condition. Control examples were the master samples from the American Type Culture Collection (ATCC). Detailed research was conducted on physiological characteristics through the formation of biofilms by yeast pathogens. Biological activity of Candida sp. biofilming was observed within 2 days with 4 hours interval in winter. Daily cultures were used for the experiment to correspond to their maximum adhesion to the glass surface. It was important to obtain 6 measurements per day with 3-5 times repetition of experiment conditions during the specified timeline. In order to determine the periodicity of the parameters studied, the data was statistically processed by Student’s t-test, using Mann–Whitney criteria and nonparametric method of least square method.It was found out that biofilming activity during 24 hours (р &lt; 0.05) of fungi exists and that all species have many principles in common. It was attested that the main rhythmometric parameters of diagnostic significance are the rhythm period and amplitude-phase stability. It was found that the daily dynamics of C. albicans 24433 biofilm formation from American Type Culture Collection was characterized by an ultradian (about 12-hours) contribution of the rhythm in the morning – 4 A.M and in the evening – 4 P.M. Significant circadian (approx. daily) rhythms of adhesion glass surface activity were revealed in C. non-albicans from American Type Culture Collection. The dynamic of biofilm formation isolates of yeast from female reproductive organs with Candida pathology was characterized by reliable ultradian (about 12-hour) harmonics which biological significance defines resistance to external impact and the ability to adaptively respond to periodic stimuli.To sum up, implementation of the chronobiological approach has opened up new prospects for studying the physiology of Сandida sp., as it enables us to predict the dynamics of microbial states and takes into account the specificity of emergency and long-term adaptation to different environmental factors. The detection of the circadian rhythm of biofilm formation activity of different Candida sp. strains provides the possibility to manage the vitality of the Society of Bacteria and Fungi and predicts its resistance to various antibiotics

Combinatorial CRISPR-Cas9 screens for de novo mapping of genetic interactions.

We developed a systematic approach to map human genetic networks by combinatorial CRISPR-Cas9 perturbations coupled to robust analysis of growth kinetics. We targeted all pairs of 73 cancer genes with dual guide RNAs in three cell lines, comprising 141,912 tests of interaction. Numerous therapeutically relevant interactions were identified, and these patterns replicated with combinatorial drugs at 75% precision. From these results, we anticipate that cellular context will be critical to synthetic-lethal therapies

Bioregulation of amplitude-phase biological activity of Candida albicans by women reproductive tract microsymbionts

In this study, we propose a chronobiological method for examining inter-microbial interactions in bacterial and fungal associations in female reproductive tract. Fungal and bacterial species were isolated in 45 women of reproductive aged 19–35, with regular menstrual cycle, applying no hormonal contraceptives, without previous gynecological surgery, abortions, miscarriages with vaginal eubiosis and dysbiosis in history. Sexually transmitted diseases (HIV infection, syphilis, gonorrhea, trichomoniasis, chlamydiosis) were excluded in all subjects. Proliferation rate, morphogenesis and phospholipase activity were examined within the 48-hour period every 4 hours, in winter time, Moon phase IV. The data obtained were assessed by using Student’s t-test, Wilcoxon test, and least squares method. All subjects were divided into the groups: group 1 — women with vaginal eubiosis, group 2 — women with vaginal dysbiosis. It was shown that in all subjects experimental parameters of C. albicans cultures showed a diurnal dynamics characterized in healthy women by circadian rhythms with a single peak of activity. However, in women with vaginal dysbiosis C. albicans was characterized by significant ultradian (around 12 hours long) rhythms with two peaks of biological activity. Concurrence and consistency in manifested physiological functions related to clinical isolates was coupled to temporal pattern of distributed biological resources in fungi depending on course of infectious process. It was found that in vaginal eubiosis exometabolites released by dominant associated microbiota did not significantly change microbiota-related amplitude-phase parameters. The data obtained evidenced that temporal pattern of parameters related to C. albicans from healthy individuals was stable and independent on bacterial metabolites. In contrast, dominant microsymbiont in vaginal dysbiosis inhibited fungi-related rhythms, which might be important in establishing lactobacillus-associated biotope colonization resistance. Effects of metabolites released by the associated microbiota typical to dysbiosis was revealed by increased mesor, amplitude, preserved biorhythm spectral pattern in examined properties as well as amplitude-phase characteristics indicating at enhanced or sustained C. albicans adaptive potential. Therefore, the amplitude-phase parameter of C. albicans physiological activity served as a marker of opposite (enhanced/weakened) effect of microsymbiont survival described in “microbial dominant-associate” pairs