The development tendencies of web analytics tools

The capabilities of website counters and methods of analyzing the tendencies of the development of various web-analytics tools are studied using Google Trends; promising approaches to more detailed research of the trends in the area of web analytics, a multi-aspect study of data from counters, services, and log analyzers aimed at optimization and promotion of websites of various organizations are presented. An overview is given for the sources of a comparative analysis of web-analytics tools, ratings, and data from the Ruward:Track laboratory on the number of added counters on the Russian Internet.     

Library Sites as Seen through the Lens of Web Analytics

This paper considers the potential of web-analytic tools for a detailed study of the main fields of work of libraries in the web environment, study of user behavior, and analysis of the relevance of library information products and services offered on the sites. It presents the parameters for assessing the audience of library web resources (attendance, traffic sources, geography of users, etc.) using plug-ins, log-analyzers, counters, ratings, and services (Google Analytics, Yandex.Metrics, and Hotlog). The sites of several world libraries are analyzed by marketing tools (Hubspot Website Grader, Nibbler, CheckTrust, Google page-speed insights, and Hemingway).     

Engineering of Escherichia coli L-serine O-acetyltransferase on the basis of crystal structure: desensitization to feedback inhibition by L-cysteine

L-Serine O-acetyltransferase (SAT) from Escherichia coli catalyzes the first step of L-cysteine synthesis in E.coli and is strictly inhibited by the second step product, L-cysteine. To establish a fermentation process to produce L-cysteine, we embarked on a mutational study of E.coli SAT to desensitize the feedback inhibition by L-cysteine. The crystal structure and the reaction mechanism of SAT from E.coli have shown that the substrate L-serine and the inhibitor L-cysteine bind to the identical region in the SAT protein. To decrease the affinity for only L-cysteine, we first built the structure model of L-serine-binding SAT on the basis of the crystal structure with bound L-cysteine and compared these two structures. The comparison showed that the Calpha of Asp92 underwent a substantial positional change upon the replacement of L-cysteine by L-serine. We then introduced various amino acid substitutions at positions 89-96 around Asp92 by randomized, fragment-directed mutagenesis to change the position of the Asp92. As a result, we successfully obtained mutant SATs which have both extreme insensitivity to an inhibition by L-cysteine (the concentration that inhibits 50% activity; IC(50) = 1,100 micromol/l, the inhibition constant; K(i) = 950.0 micromol/l) and extremely high emzymatic activities.     

Mechanical Properties and Corrosion Resistance of Hard β-W based CVD Coatings in Aqueous NaCl Solution

Protection of Metals and Physical Chemistry of Surfaces - The paper presents the results of studying the mechanical and anticorrosive properties of coatings based on the metastable tungsten phase...     

Corrosion and Electrochemical Behavior of β-W CVD Coatings in NaCl Solution

Protection of Metals and Physical Chemistry of Surfaces - The paper presents the results of a study of the corrosion-electrochemical behavior of coatings based on the metastable phase of tungsten...     

The influence of bridge groups nature in diepoxy compounds on kinetics of curing process by diamines and on physical and mechanical properties of forming polymers

Summary In the present work the initial monomer reactivity in curing reaction of epoxy compounds by aromatic diamines has been investigated. Also physical and mechanical properties of cured polumers of diglycidyl ethers 4,4-bisaromatic compounds with bridge groups have been examined.