20 research outputs found

    Propionate and butyrate dependent bacterial sulfate reduction at extremely haloalkaline conditions and description of Desulfobotulus alkaliphilus sp. nov.

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    Evidence on the utilization of simple fatty acids by sulfate-reducing bacteria (SRB) at extremely haloalkaline conditions are practically absent, except for a single case of syntrophy by Desulfonatronum on acetate. Our experiments with sediments from soda lakes of Kulunda Steppe (Altai, Russia) showed sulfide production with sulfate as electron acceptor and propionate and butyrate (but not acetate) as an electron donor at a pH 10–10.5 and a salinity 70–180 g l−1. With propionate as substrate, a highly enriched sulfidogenic culture was obtained in which the main component was identified as a novel representative of the family Syntrophobacteraceae. With butyrate as substrate, a pure SRB culture was isolated which oxidized butyrate and some higher fatty acids incompletely to acetate. The strain represents the first haloalkaliphilic representative of the family Desulfobacteraceae and is described as Desulfobotulus alkaliphilus sp. nov

    Genomics of alkaliphiles

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    Alkalinicity presents a challenge for life due to a “reversed” proton gradient that is unfavourable to many bioenergetic processes across the membranes of microorganisms. Despite this, many bacteria, archaea, and eukaryotes, collectively termed alkaliphiles, are adapted to life in alkaline ecosystems and are of great scientific and biotechnological interest due to their niche specialization and ability to produce highly stable enzymes. Advances in next-generation sequencing technologies have propelled not only the genomic characterization of many alkaliphilic microorganisms that have been isolated from nature alkaline sources but also our understanding of the functional relationships between different taxa in microbial communities living in these ecosystems. In this review, we discuss the genetics and molecular biology of alkaliphiles from an “omics” point of view, focusing on how metagenomics and transcriptomics have contributed to our understanding of these extremophiles.https://link.springer.com/bookseries/10hj2021BiochemistryGeneticsMicrobiology and Plant Patholog

    A Novel Image Transformation For Solving Complex Image Mapping Problems

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    The paper proposes a novel image transformation called Image Local Response (ILR) that can be used for solving complex image mapping problems. The proposed transformation brings together two approaches based on the pixel value distribution and image features. Image local response is defined as the average value of the difference between the transformed and the original copies of the same image whereby the transformation is small, i.e., the components of the corresponding parameter vector have sufficiently small unit values. The response has a few interesting properties useful in image mapping. The validity of the proposed image transformation is shown on sample complex image mapping problems formulated as the multi-objective piecewise imaging optimization problem

    Russian company investment project valuation with the built-in abandon option

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    This paper is dedicated to development of models and numerical methods for evaluating investment projects of Russian companies using the real options model. In the current economic conditions, it is highly necessary to properly reflect the flexibility of the company’s in adapting management decisions in response to changing market conditions. In this regard, the traditional models of investment analysis can be supplemented, and in some cases replaced by alternative approaches, for example, by estimating the present value of a call (put) option using the Black-Scholes-Merton formula. The above given statement determines the relevance of the study. The paper presents theoretical and practical aspects of the use of traditional and optional approaches to the evaluation of investment projects. It also presents practical calculations for investment project related to implementation of automated information system for compiling consolidated statements for a group of companies whose assessments need to take into account a real option to abandon the project
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