On the Rate of Convergence for a Characteristic of Multidimensional Birth-Death Process

We consider a multidimensional inhomogeneous birth-death process (BDP) and obtain bounds on the rate of convergence for the corresponding one-dimensional processes

Three Stages and Main Provisions of Institutionalization of International Forums in Solving Global Economic Problems (1997–2020)

This article examines the institutional development of a forum, taking SPIEF and the Roscongress Foundation as a case study. The organization and event can be loosely divided into three periods: parliamentary (1997–2005), governmental (2006–2015), and presidential (2016 — present day). The article sets forth the minimum criteria of the work involved. The three periods are analysed, along with the need for each transition, and the organizational process involved for each one. Factors underpinning the stability of the system as a whole also come under examination

Genetic Diversity in Local Taraxacum officinale L. Populations from Habitats Varied in Toxic Load

The level of lipid peroxidation (a stress indicator) and the quantitative traits of leaf tissue (the number and size of mesophyll cells and chloroplasts) were determined in Taraxacum officinale L. plants from five habitats near the city of Nizhniy Tagil that differ in terms of the heavy metal content in the soil. It is shown that in pollutedhabitats, the content of heavy metals (Cu2+ and Zn2+) in leaves is significantly higher compared to plants from background areas, with leaf thickness, mesophyll cell volume and chloroplast number per cell increasing. Both Inter Simple Sequence Repeat (ISSR) analysis and cluster analysis of dandelion genetic diversity based oneight primers have revealed that four groups of plants are closely related genetically. Of the observed differences between five local populations, 78% are caused by intrapopulation variability and 22% by interpopulation variability. It is supposed that Taraxacum officinale’s tolerance to heavy metal contamination in the studied localities is not genetically fixed adaptation, but acclimation within genetically selected rangesof tolerance. Keywords: heavy metals, local populations, ISSR markers, leaf trait

Prediction of some peroxidase functions in Arabidopsis thaliana L. By bioinformatic search

Peroxidases of class III are common in various organisms. They are involved in lignin biosynthesis and plant protection against stressors. Peroxidases are presented in many isoforms, whose role is not always clear. The aim of this study is to analyze the amino acid sequences of reference peroxidases with known functions and peroxidases from Arabidopsis thaliana L. whose functions are unknown and to consider their putative roles in lignin biosynthesis. The structural and functional organization of peroxidases was analyzed by bioinformatical methods applied to open Internet sources. Seven reference peroxidases were chosen from four plant species: Zinnia sp., Armoracia rusticana P.G. Gaertn., Lycopersicon esculentum L. N Populus alba L. Twenty-four amino acid sequences of homologous peroxidases from A. thaliana were selected for the analyses with the BLAST service. Their molecular weights and isoelectric points were calculated. Multiple alignments of amino acid sequences and phylogenetic analysis were done. Sites of binding to monolignol substrates were identified in seven peroxidases from A. thaliana, and the enzymes were assigned to the groups of S- or G-peroxidases. Amino acid replacements in the primary structures of peroxidases were analyzed. Peroxidases from A. thaliana were clustered with reference peroxidases. They formed six clusters on the phylogenetic tree, three of which contained only A. thaliana peroxidases. Peroxidases within each cluster had similar molecular weights and isoelectric points, common localization of expression, and similar functions. Thus, the use of bioinformatics, databases, and published data bring us to assumptions as to the functions of several A. thaliana class III peroxidases. AtPrx39 peroxidase was shown to be affine to sinapyl alcohol; AtPrx54, to p-coumaryl and coniferyl alcohols. They are likely to participate in lignin biosynthesis. © Tugbaeva A.S., Ermoshin A.A., Kiseleva I.S., 2019

Where to Go on Your Next Trip? Optimizing Travel Destinations Based on User Preferences

Recommendation based on user preferences is a common task for e-commerce websites. New recommendation algorithms are often evaluated by offline comparison to baseline algorithms such as recommending random or the most popular items. Here, we investigate how these algorithms themselves perform and compare to the operational production system in large scale online experiments in a real-world application. Specifically, we focus on recommending travel destinations at Booking.com, a major online travel site, to users searching for their preferred vacation activities. To build ranking models we use multi-criteria rating data provided by previous users after their stay at a destination. We implement three methods and compare them to the current baseline in Booking.com: random, most popular, and Naive Bayes. Our general conclusion is that, in an online A/B test with live users, our Naive-Bayes based ranker increased user engagement significantly over the current online system.Comment: 6 pages, 2 figures in SIGIR 2015, SIRIP Symposium on IR in Practic