Comparative analysis of universal methods no reference quality assessment of digital images

The main purpose of this article is to conduct a comparative study of two well-known no-reference image quality assessment algorithms BRISQUE and NIQE in order to analyze the relationship between subjective and quantitative assessments of image quality. As experimental data, we used images with artificially created distortions and mean expert assessments of their quality from the public databases TID2013, CISQ and LIVE. Image quality scores were calculated using the NIQE, BRISQUE functions and their average. The correlation coefficients of Pearson, Spearman and Kendall were analyzed between expert visual assessments and quantitative scores of the image quality, as well as between the values of three compared indicators. For the experiments, the Matlab system and values of its functions niqe and brisque normalized to the range [0, 1] were used. The computation time of niqe is slightly less. The investigated functions poorly estimate the contrast of images, but the additive Gaussian noise, Gaussian blur and loss in compression by the JPEG2000 algorithm are better. The BRISQUE measure shows slightly better results when evaluating images with additive Gaussian noise, while NIQE for blurred by Gaussian. The average of the normalized values of NIQE and BRISQUE is a good compromise. The results of this work may be of interest for the practical implementations of digital image analysis

Тransplastomic tobacco plants producing the hydrophilic domain of the sheep pox virus coat protein L1R

Sheep pox has a wide geographical range of distribution and poses a threat to sheep breeding worldwide, as the disease is highly contagious and is accompanied by large economic losses. Vaccines based on live attenuated virus strains are currently being used for prevention of this disease. Such vaccines are effective, but potentially dangerous because of the possible virus reversion to a pathogenic state. The development of safe recombinant subunit vaccines against sheep pox is very relevant. The high ploidy level of the plant chloroplasts makes it possible to obtain large quantities of foreign proteins. The purpose of this study was to create transplastomic Nicotiana tabacum plants producing one of the candidate vaccine proteins of sheep pox virus L1R. A vector containing a deletion variant of the SPPV_56 gene, which encodes the N-terminal hydrophilic part of the viral coat protein L1R, was constructed to transform tobacco plastids. It provides integration of the transgene into the trnG/trnfM region of the chloroplast tobacco genome by homologous recombination. Spectinomycin-resistant tobacco lines were obtained by biolistic gun-mediated genetic transformation. PCR analysis in the presence of gene-specific primers confirmed integration of the transgene into the plant genome. Subsequent Northern and Western blot analysis showed the gene expression at the transcriptional and translational levels. The recombinant protein yields reached up to 0.9 % of total soluble protein. The transplastomic plants displayed a growth retardation and pale green leaf color compared to the wild type, but they developed normally and produced seeds. Southern blot analysis showed heteroplasmy of the plastids in the obtained plants due to recombination events between native and introduced regulatory plastid DNA elements. The recombinant protein from plant tissue was purified using metal affinity chromatography. Future research will be focused on determining the potential of the chloroplast-produced protein to induce neutralizing antibodies against SPPV strains

Influence of nettle powder addition on bread quality indicators

This article reflects the results of a study on the effect of nettle leaf powder on the physicochemical and organoleptic characteristics of wheat bread. Nettle leaves is a good source of proteins, fibers, minerals and other bioactive compounds and it could be an ideal ingredient for improving the nutritional value of bread and bakery products. Nettle leaf powder was mixed with wheat flour in different ratios: 1 %, 3 % and 5 % to prepare bread samples. The results showed a significant increase in the protein, ash and fiber content of bread. The specific volume of the bread decreased as the level of nettle leaf powder increased due to a decrease in the gluten content of the mixture and due to the interaction between dietary fiber components, water and gluten. Substitutions of 1 %, 3 % and 5 % give parameter values at least the same as the control sample and give acceptable indicators of bread quality in terms of specific volume and organoleptic properties

Generation of Magnetic Field by Combined Action of Turbulence and Shear

The feasibility of a mean-field dynamo in nonhelical turbulence with superimposed linear shear is studied numerically in elongated shearing boxes. Exponential growth of magnetic field at scales much larger than the outer scale of the turbulence is found. The charateristic scale of the field is l_B ~ S^{-1/2} and growth rate is gamma ~ S, where S is the shearing rate. This newly discovered shear dynamo effect potentially represents a very generic mechanism for generating large-scale magnetic fields in a broad class of astrophysical systems with spatially coherent mean flows.Comment: 4 pages, 5 figures; replaced with revised version that matches the published PR

Fluctuation dynamo and turbulent induction at low magnetic Prandtl numbers

This paper is a detailed report on a programme of simulations used to settle a long-standing issue in the dynamo theory and demonstrate that the fluctuation dynamo exists in the limit of large magnetic Reynolds number Rm>>1 and small magnetic Prandtl number Pm<<1. The dependence of the critical Rm_c vs. the hydrodynamic Reynolds number Re is obtained for 1<Re<6700. In the limit Pm<<1, Rm_c is ~3 times larger than for Pm>1. The stability curve Rm_c(Re) (and, it is argued, the nature of the dynamo) is substantially different from the case of the simulations and liquid-metal experiments with a mean flow. It is not as yet possible to determine numerically whether the growth rate is ~Rm^{1/2} in the limit Re>>Rm>>1, as should be the case if the dynamo is driven by the inertial-range motions. The magnetic-energy spectrum in the low-Pm regime is qualitatively different from the Pm>1 case and appears to develop a negative spectral slope, although current resolutions are insufficient to determine its asymptotic form. At 1<Rm<Rm_c, the magnetic fluctuations induced via the tangling by turbulence of a weak mean field are investigated and the possibility of a k^{-1} spectrum above the resistive scale is examined. At low Rm<1, the induced fluctuations are well described by the quasistatic approximation; the k^{-11/3} spectrum is confirmed for the first time in direct numerical simulations.Comment: IoP latex, 27 pages, 25 figures, 3 tables. Accepted by New J. Physic

Evaluation of the technological properties of down based on the technology of dying the down of goats of coarse-haired, down and wool breeds

The article is devoted to the study and assessment of the technological properties of down based on the technology of dyeing down from goat wool from various genotypes of goats of the republic. The dyeing was carried out under laboratory conditions with Italian dyes. The dependence of the color intensity for downy fibers is described by polynomial equations of the second and third degree. It has been shown that goat down fibers have good dyeing ability, dyeing uniformity and show good dyeing performance in standard modes

Constructing the constitutively active ribosomal protein S6 kinase 2 from <i>Arabidopsis thaliana</i> (AtRPS6K2) and testing its activity <i>in vitro</i>

Ribosomal protein S6 (RPS6) is the only phosphorylatable protein of the eukaryotic 40S ribosomal subunit. Ribosomes with phosphorylated RPS6 can selectively translate 5’TOP-(5’-terminal oligopyrimidine)-containing mRNAs that encode most proteins of the translation apparatus. The study of translational control of 5’TOP-mRNAs, which are preferentially translated when RPS6 is phosphorylated and cease to be translated when RPS6 is de-phosphorylated, is particularly important. In Arabidopsis thaliana, AtRPS6 is phosphorylated by kinase AtRPS6K2, which should in turn be phosphorylated by upper level kinases (AtPDK1 – at serine (S) 296, AtTOR – at threonine (T) 455 and S437) for full activation. We have cloned AtRPS6K2 cDNA gene and carried out in vitro mutagenesis replacing codons encoding S296, S437 and T455 by triplets of phosphomimetic glutamic acid (E). After the expression of both natural and mutated cDNAs in Escherichia coli cells, two recombinant proteins were isolated: native AtRPS6K2 and presumably constitutively active AtRPS6K2(S296E, S437E, T455E). The activity of these variants was tested in vitro. Both kinases could phosphorylate wheat (Triticum aestivum L.) TaRPS6 as part of 40S ribosomal subunits isolated from wheat embryos, though the non-mutated variant had less activity than phosphomimetic one. The ability of recombinant non-mutated kinase to phosphorylate TaRPS6 can be explained by its phosphorylation by bacterial kinases during the expression and isolation steps. The phosphomimetically mutated AtRPS6K2(S296E, S437E, T455E) can serve as a tool to investigate preferential translation of 5’TOP-mRNAs in wheat germ cell-free system, in which most of 40S ribosomal subunits have phosphorylated TaRPS6. Besides, such an approach has a biotechnological application in producing genetically modified plants with increased biomass and productivity through stimulation of cell growth and division

Evidence that phosphorylation of the alpha-subunit of eIF2 does not essentially inhibit mRNA translation in wheat germ cell-free system.

A mechanism based on reversible phosphorylation of the α-subunit of eukaryotic initiation factor 2 (eIF2α) has been confirmed as an important regulatory pathway for inhibition of protein synthesis in mammalian and yeast cells, while plants constitute the significant exception. We studied the induction of TaeIF2α phosphorylation in germinated wheat (Triticum aestivum) embryos subjected to different adverse conditions. Data confirmed that formation of TaeIF2(αP) was not a general response, as no phosphorylation was observed under salt, oxidative or heat stress. Nevertheless, treatment by salicylic acid, UV-light, cold shock and histidinol did induce phosphorylation of TaeIF2α of wheat, as has been established previously for AteIF2α in Arabidopsis (Arabidopsis thaliana). Influence of TaeIF2α phosphorylation on translation of reporter mRNA with different 5′-untranslated regions (5′UTRs) was studied in wheat germ cell-free system (WG-CFS), in which TaeIF2α was first phosphorylated either by heterologous recombinant human protein kinase, HsPKR (activated by double-stranded (ds)RNA), or by endogenous protein kinase TaGCN2 (activated by histidinol). Pre-treatment of WG-CFS with HsPKR in the presence of dsRNA or with histidinol resulted in intense phosphorylation of TaeIF2α; however, the translation levels of all tested mRNAs decreased by only 10–15% and remained relatively high. In addition, factor OceIF2 from rabbit (Oryctolagus cuniculus) bound GDP much more strongly than the homologous factor TaeIF2 from wheat germ. Furthermore, factor OceIF2B was able to stimulate guanine nucleotides exchange (GDP→GTP) on OceIF2 but had no effect on the similar exchange on TaeIF2. These results suggest that the mechanism of stress response via eIF2α phosphorylation is not identical in all eukaryotes and further research is required to find and study in detail new plant-specific mechanisms that may inhibit overall protein synthesis in plants under stress

Demarcation of the Boundaries of the Central Asian Desert Natural Focus of Plague of Kazakhstan and Monitoring the Areal of the Main Carrier, <I>Rhombomys opimus</I>

The aim of the study was to clarify the boundaries of the Central Asian natural plague focus of Kazakhstan and the modern boundaries of the areal of the great gerbil (Rhombomys opimus) in order to improve epizootiological monitoring and increase the effectiveness of preventive (anti-epidemic) measures.Materials and methods. Data from the epizootiological monitoring of the great gerbil populations in 14 autonomous foci of the Central Asian desert natural plague focus in the Republic of Kazakhstan between 2010 and 2020 were used for the analysis. An epizootiologic survey of an area of 875350 km2 was carried out. When processing the data, epidemiological, epizootiological, statistical research methods, as well as GIS technologies were used.Results and discussion. An increase in the total area of the Central Asian desert natural plague focus of the Republic of Kazakhstan by 79710 km2 (9.98 %) has been established for the period of 1990–2020. It is noted that the change in the area of plague-enzootic territory was a consequence of the ever changing areal of the main carrier of plague pathogen – the great gerbil – under the influence of climatic and anthropogenic factors. The most significant changes were found in the southeastern part of the plague-enzootic territory, including those for the Betpakdala (50 %), Balkhash (34.3 %), Taukum (13.3 %) and Mojynkum (0.32 %) autonomous foci. The area of the Aryskum-Dariyalyktakyr autonomous focus decreased by 2100 km2 (4 %). In 2000–2002, new Alakol’sky and Ili intermountain autonomous foci with a total area of 26759 km2 were discovered. It is shown that due to the regression of the Aral Sea, the areal of the great girbil expanded and the area of the North Aral and Kyzylkum natural plague foci increased by 10500 km2 (29.2 %) and 560 km2 (0.4%), respectively. The areas of the Aral-Karakum and UralEmba desert autonomous foci, on the contrary, decreased by 2000 km2 (2.6 %) and 12300 km2 (17.6 %), respectively. Passportization and landscape-epizootiologic zoning of the territory of the Central Asian desert natural plague focus of the Republic of Kazakhstan has been completed