High-Q bismuth silicate nonlinear glass microsphere resonators

The fabrication and characterization of a bismuth-silicate glass microsphere resonator has been demonstrated. At wavelengths near 1550 nm, high-modes can be efficiently excited in a 179 µm diameter bismuth-silicate glass microsphere via evanescent coupling using a tapered silica fiber with a waist diameter of circa 2 µm. Resonances with Q-factors as high as were observed. The dependence of the spectral response on variations in the input power level was studied in detail to gain an insight into power-dependent thermal resonance shifts. Because of their high nonlinearity and high- factors, bismuth-silicate glass microspheres offer the potential for robustly assembled fully integrated all-optical switching devices

An SMS fiber structure based on a chalcogenide multimode fiber

We theoretically and experimentally investigate a singlemode-multimode-singlemode (SMS) structure based on chalcogenide (As2S3) multimode fiber and conventional silica singlemode fibers. The experimental results show a general agreement with the numerical simulation results based on a wide angle-beam propagation method (WA-BPM). The chalcogenide fiber and silica fibers were mechanically spliced and packaged using a UV cured polymer with a low refractive index on a microscope slide. Multimode interference variation was observed by photo-induced refractive index changes resulting from both a localized laser irradiation at a wavelength of 405 nm and a UV lamp. Our result provides a platform for the development of compact, high-optical-quality, and robust photonic nonlinear devices

Optical bistability in a GaAs based polariton diode

We report on a new type of optical nonlinearity in a polariton p-i-n microcavity. Abrupt switching between the strong and weak coupling regime is induced by controlling the electric field within the cavity. As a consequence bistable cycles are observed for low optical powers (2-3 orders of magnitude less than for Kerr induced bistability). Signatures of switching fronts propagating through the whole 300 microns x 300 microns mesa surface are evidenced.Comment: 5 pages 3 figure

Investigation of interaction femtosecond laser pulses with skin and eyes mathematical model

We present a mathematical model of linear and nonlinear processes that takes place under the action of femtosecond laser radiation on the cutaneous covering. The study is carried out and the analytical solution of the set of equations describing the dynamics of the electron and atomic subsystems and investigated the processes of linear and nonlinear interaction of femtosecond laser pulses in the vitreous of the human eye, revealed the dependence of the pulse duration on the retina of the duration of the input pulse and found the value of the radiation power density, in which there is a self-focusing is obtained. The results of the work can be used to determine the maximum acceptable energy, generated by femtosecond laser systems, and to develop Russian laser safety standards for femtosecond laser systems

FUNCTIONAL FOOD COMPOSITIONS BASED ON WHEY PROTEIN ISOLATE, FISH OIL AND SOY PHOSPHOLIPIDS

The aim of the research was to study the impact of whey protein isolate on the solubility and oxidative stability of the lipid composition based on soy phosphatidylcholine and fish oil. The relationship between the molecular parameters (density; ζ-potential) of the formed complex particles and their functional properties was found using laser light scattering (static, dynamic, electrophoretic) and spectrophotometry. The studied compositions could be used as the basis for the development of multifunctional food additives with an objective of the enrichment of foods and beverages with omega-3 polyunsaturated fatty acids (PUFAs). The main advantages of such composition are a high level of protection of the lipids against oxidation and degradation, a high solubility in an aqueous medium and the clean label.The aim of the research was to study the impact of whey protein isolate on the solubility and oxidative stability of the lipid composition based on soy phosphatidylcholine and fish oil. The relationship between the molecular parameters (density; ζ-potential) of the formed complex particles and their functional properties was found using laser light scattering (static, dynamic, electrophoretic) and spectrophotometry. The studied compositions could be used as the basis for the development of multifunctional food additives with an objective of the enrichment of foods and beverages with omega-3 polyunsaturated fatty acids (PUFAs). The main advantages of such composition are a high level of protection of the lipids against oxidation and degradation, a high solubility in an aqueous medium and the clean label

Directions to improve economic efficiency of regional production

The paper provides theoretical grounding and the directions for improving the economic efficiency of the regional feedstuff production. The study develops a conceptual model of distributing management functions of feedstuff production between the regional authorities of state sectoral and economic management and the district level. The authors suggest the methodology for calculating potential capacity of intraregional feedstuff market, considering the demands of all categories of agricultural manufacturers. The study examines possibilities for implementing the strategy of diversified growth and development of the intraregional feedstuff market, including the terms of interaction between the large and micro-business inside the industry and cooperation of micro-business feedstuff manufacturers with agricultural production. The authors have developed the methodology for assessing the efficiency of feedstuff production, based on the aggregate estimation of the management organization, conditions for the development of feedstuff production and changes in the feedstuff production and livestock breeding industry.peer-reviewe

Experimental Demonstration of Nanolaser with sub-μ\muA Threshold Current

We demonstrate a photonic crystal nanolaser exhibiting an ultra-low threshold of 730 nA at telecom wavelengths. The laser can be directly modulated at 3 GHz at an energy cost of 1 fJ/bit. This is the lowest threshold reported for any laser operating at room temperature and facilitates low-energy on-chip links.Comment: 3 pages with 2 figure

Postslaughter state of muscle tissue of pigs depending on the duration of pre-slaughter fasting

Changes in the muscle tissue microstructure lead to changes in meat quality. One of the causes of the myopathy development is animal stress. Pigs experience the strongest stress during pre-slaughter holding. The study of the postmortem meat structure depending on fasting time is a topical task. The objects of the research were samples of m. L. dorsi obtained after slaughter from pigs that differed in fasting time: 4 (group 1), 8 (group 2), 10 (group 3), 16 (group 4) and 18 (group 5) hours (N = 20, n = 4). Investigation of the microstructure and morphometric measurements were carried out on preparations stained with hematoxylin and eosin. Myopathic changes in muscle tissue were assessed using a semi-quantitative method developed earlier. All studied samples were characterized by the uniform condition of muscle tissue. Statistically significant differences between individual groups were observed regarding the number and area of giant fibers, sarcomere length, diameter of muscle fibers and proportion of muscle fibers, which diameter was lower or higher by 1/3 than the mean fiber diameter. An increase in the pre-slaughter holding time reduced the number and area of giant fibers (r = –0.8437 and –0.5796, respectively), as well as the diameter of “normal” fibers (r = –0.5337), which positively influenced pork quality. Groups 1, 2 and 3 were characterized by the presence of signs of moderate and pronounced myopathy. Only one carcass with pronounced myopathic signs was revealed in each of groups 4 and 5. In group 4, one carcass did not have signs of myopathy. Pre-slaughter holding during 4, 8 and 10 hours led to deterioration of pork quality. The recommended fasting time is 16 hours

A comparison of the characteristics of extreme drought during the late 20 th and early 21st centuries over Eurasia and North America

The atmospheric general circulation character during summer droughts over Eastern Europe / Western Russia and North America from 1970-2020 is examined here. A criterion to examine atmospheric drought events encompassed the summer season was used to determine which years were driest using precipitation, evaporation, and areal coverage. The relationship between drought and atmospheric character using the Dzerzeevsky climatic classification scheme, atmospheric blocking, teleconnections, and information entropy are used to study the atmospheric dynamic

Strawberry resistance to the major fungal phytopathogens: R-genes and their DNA markers

The garden strawberry Fragaria × ananassa (Duchesne ex Weston) Duchesne ex Rozier (1785) is a perennial herbaceous plant of the Rosaceae family; it is cultivated all around the world. It accounts for more than half of the global volume of berries production. In Russia, more than 160 tons of garden strawberries are grown annually, but according to Russian scientists, this crop has a much higher productivity potential. Various pathogens, including bacterial, viral and fungal infections, negatively affect the productivity of strawberry. Anthracnose (caused by Colletotrichum Corda.), crown rot (Phytophthora cactorum Lebert & Cohn), red core disease (Phytophthora fragariae var. fragariae Hickman), fusarium wilt (Fusarium oxysporum f. sр. fragariae Winks & Williams ) and strawberry powdery mildew (Podosphaera aphanis [Sphaerotheca macularis] (Wallr.) U. Braun & S. Takam) are among the most important fungal diseases of strawberry. This review discusses the current data about the known genes and quantitative trait loci (QTLs) associated with resistance to listed plant pathogens. The review also offers information about molecular markers of different types: SDRF, AFLP, SSR, SCAR, SNP, associated with these genes/QTLs and used in the molecular screening of strawberry collections for practical purposes