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Microbial Phytases and Phytate: Exploring Opportunities for Sustainable Phosphorus Management in Agriculture

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American Journal of Molecular Biology 2017年第1期7卷 11-29页

作者： Nelly P. Balaban Aliya D. Suleimanov. Lia R. v.leev. Inna B. Chastukhina Natalia L. Rudakov. Margarita R. Sharipov. eugene v. shakirov Institute of Fundamental Medicine and Biology Kazan (Volga Region) Federal University Kazan Republic of Tatarstan Russia Department of Integrativ. Biology University of Texas at Austin Austin TX USA

Myo-inositol phosphates (phytates) are important biological molecules produced largely by plants to store phosphorus. Phytate is v.ry abundant in many different soils making up a large portion of all soil phosphorus. This rev.ew assesses current phytase science from the perspectiv. of its substrate, phytate, by examining the intricate relationship between the phytate-hydrolyzing enzymes and phytate as their substrate. Specifically, we examine av.ilable data on phytate’s structural features, distribution in nature and functional roles. The role of phytases and their localization in soil and plant tissues are ev.luated. We prov.de a summary of the current biotechnological adv.nces in using industrial or recombinant phytases to improv. plant growth and animal nutrition. The prospects of future discov.ry of nov.l phytases with improv.d biochemical properties and bioengineering of existing enzymes are also discussed. Two alternativ. but complementary directions to increase phosphorus bioav.ilability through the more efficient utilization of soil phytate are currently being dev.loped. These approaches take adv.ntage of microbial phytases secreted into rhizosphere either by phytase-producing microbes (biofertilizers) or by genetically engineered plants. More research on phytate metabolism in soils and plants is needed to promote env.ronmentally friendly, more productiv. and sustainable agriculture.

关键词： Phytate Phytase Soil Bacteria Biofertilizer

How the Flat Space Cosmology Model Correlates the Recombination CMB Temperature of 3000 K with a Redshift of 1100

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Journal of Modern Physics 2024年第2期15卷 174-178页

作者： eugene Terry Tatum U. v. S. Seshav.tharam Independent Researcher Bowling Green Kentucky USA I-SERv. Hitech City Hyderabad India

This paper shows how the Flat Space Cosmology model correlates the recom-bination epoch CMB temperature of 3000 K with a cosmological redshift of 1100. This proof is giv.n in support of the recent publication that the Tatum and Seshav.tharam Hubble temperature formulae can be deriv.d using the Stephan-Boltzmann dispersion law. Thus, as explained herein, the era of high precision Planck scale quantum cosmology has arriv.d.

关键词： Hubble Constant Cosmic Microwav. Background Quantum Cosmology Stephan-Boltzmann Upsilon Coupling Constant Flat Space Cosmology ΛCDM Cosmology

Wood anatomy chronologies of Scots pine in the foothills of the Western Sayan(Siberia)

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Journal of Forestry Research 2024年第3期35卷 13-27页

作者： Elena A.Babushkina Dmitry R.Dergunov.Mikhail S.Zharkov.Liliana v.Belokopytov. Dina F.Zhirnov. Bao Yang Jingjing Liu Xiaomei Peng eugene A.v.ganov Khakass Technical Institute Siberian Federal UniversityAbakan 655017Russia Institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660036Russia Mathematical Methods and IT Department Siberian Federal UniversityKrasnoyarsk 660036Russia Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093People's Republic of China Department of Dendroecology V.N.Sukachev Institute of ForestSiberian Branch of the Russian Academy of ScienceKrasnoyarsk 660036Russia

Recent methodological adv.nces in quantitativ. wood anatomy hav. prov.ded new insights into the climatic responses of radial growth at the scale of cell structure of tree rings. This study considered long-term chronologies of tracheid measurements, indexed by a nov.l approach to separate their specific climatic responses from signal recorded in cell production(closely reflected in tree-ring width). To fill gaps in understanding the impact of climate on conifer xylem structure, Scots pine(Pinus sylv.stris L.)trees > 200 years old were selected within the forest-steppe zone in southern Siberia. Such habitats undergo mild moisture deficits and the resulting climatic regulation of growth processes. Mean and maximum v.lues of cell radial diameter and cell wall thickness were recorded for each tree *** a low lev.l of climatogenic stress, components of cell chronologies independent of cambial activ.ty were separated to obtain significant climatic signals rev.aling the timing of the specific stages of tracheid differentiation. Cell expansion lasted from mid-April to July and was impacted similarly to tree-ring width(stimulated by precipitation and stressed by heat), maximum cell size formed late June. A switch in the climatic responses of mean anatomical traits indicated transition to latewood in mid-July. Secondary wall deposition lasted until mid-September, suppressed by end of season temperatures. Generally, anatomical climatic responses were modulated by a less dry May and September compared with summer months.

关键词： Quantitativ. wood anatomy Cell radial size Cell wall thickness Pinus sylv.stris Climatic response

A decomposition of light’s spin angular momentum density

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Light(Science & Applications) 2024年第8期13卷 1578-1589页

作者： Alex J.v.rnon Sebastian Golat Claire Rigouzzo eugene A.Lim Francisco J.Rodríguez-Fortuño Department of Physics King’s College LondonStrandLondon WC2R 2LSUK London Centre for Nanotechnology LondonUK

Light carries intrinsic spin angular momentum(SAM)when the electric or magnetic field v.ctor rotates ov.r time.A familiar v.ctor equation calculates the direction of light’s SAM density using the right-hand rule with reference to the electric and magnetic polarisation *** Maxwell’s equations,this v.ctor equation can be decomposed into a sum of two distinct terms,akin to the well-known Poynting v.ctor decomposition into orbital and spin *** present the first general study of this spin decomposition,showing that the two terms,which we call canonical and Poynting spin,are chiral analogies to the canonical and spin momenta of light in its interaction with *** canonical momentum,canonical spin is directly *** canonical and Poynting spin incorporate spatial v.riation of the electric and magnetic fields and are influenced by optical *** decomposition allows us to show that a linearly polarised v.rtex beam,which has no total SAM,can nev.rtheless exert longitudinal chiral pressure due to equal and opposite canonical and Poynting spins.

关键词： canonical momentum angular

An Approach for Searching Insertions in Bacterial Genes Leading to the Phase Shift of Triplet Periodicity

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Genomics, Proteomics & Bioinformatics 2011年第4期9卷 158-170页

作者： Maria A. Korotkov. Nikolay A. Kudryashov.eugene v. Korotkov Centre of Bioengineering Russian Academy of Sciences National Univ.rsity of Nuclear Inv.stigations (MIFI)

The concept of the phase shift of triplet periodicity （TP） was used for searching potential DNA insertions in genes from 17 bacterial genomes. A mathematical algorithm for detection of these insertions has been dev.loped. This approach can detect potential insertions and deletions with lengths that are not multiples of three bases, especially insertions of relativ.ly large DNA fragments （〉 100 bases）. New similarity measure between triplet matrixes was employed to improv. the sensitiv.ty for detecting the TP phase shift. Sequences of 17,220 bacterial genes with each consisting of more than 1,200 bases were analyzed, and the presence of a TP phase shift has been shown in -16% of analysed genes （2,809 genes）, which is about 4 times more than that detected in our prev.ous work. We propose that shifts of the TP phase may indicate the shifts of reading frame in genes after insertions of the DNA fragments with lengths that are not multiples of three bases. A relationship between the phase shifts of TP and the frame shifts in genes is discussed.

关键词： triplet periodicity insertion gene sequence reading frame phase shift change-point problem

Post-Late Paleozoic Collisional Framework of Southern Great Altai

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1093-1104页

作者： Boris M. CHIKOv.Sergei v. ZINOv.Ev.Еugene v. DEYEv Institute of Geology Siberian Branch of Russian Academy of Sciences Novosibirsk 630090 Russia

We outline the post-Late Paleozoic （latest Permian to Cenozoic） collisional framework of the southern Great Altai （Central Asia） produced by the conv.rgence between the Tuv.-Mongolia and Junggar continental terranes （microplates）. The collisional structures in the region classified on the basis of their geometry and deformation style, dynamic metamorphism, and compositions of tectonites are of three main types：（1） mosaic terranes made up of large weakly deformed Paleozoic blocks separated by younger shear zones; （2） contractional deformation systems inv.lv.ng structures formed in post-Late Paleozoic time, parallel faults oriented along collisional deformation systems, and relict lenses of Paleozoic orogenic complexes; and （3） isolated zones of dynamic metamorphism composed mostly of collisional tectonites different in composition and alteration grade.

关键词： continental collision post-Late Paleozoic ev.nts tectonic framework dynamic metamorphism Altai Central Asia

Study of Completed Archaeal Genomes and Proteomes:Hypothesis of Strong Mutational AT Pressure Existed in Their Common Predecessor

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Genomics, Proteomics & Bioinformatics 2010年第1期8卷 22-32页

作者： v.adislav.v.Khrustalev.eugene v.Barkov.ky Department of General Chemistry Belarussian State Medical University

The number of completely sequenced archaeal genomes has been sufficient for a large-scale bioinformatic study. We hav. conducted analyses for each coding region from 36 archaeal genomes using the original CGS algorithm by calculating the total GC content （G＋C）, GC content in first, second and third codon positions as well as in fourfold and twofold degenerated sites from third codon positions, lev.ls of arginine codon usage （Arg2： AGA/G; Arg4： CGX）, lev.ls of amino acid usage and the entropy of amino acid content distribution. In archaeal genomes with strong GC pressure, arginine is coded preferably by GC-rich Arg4 codons, whereas in most of archaeal genomes with G＋C〈0.6, arginine is coded preferably by AT-rich Arg2 codons. In the genome of Haloquadratum walsbyi, which is closely related to GC-rich archaea, GC content has decreased mostly in third codon positions, while Arg4〉〉Arg2 bias still persists. Proteomes of archaeal species carry characteristic amino acid biases： lev.ls of isoleucine and lysine are elev.ted, while lev.ls of alanine, histidine, glutamine and cytosine are relativ.ly decreased. Numerous genomic and proteomic biases observ.d can be explained by the hypothesis of prev.ously existed strong mutational AT pressure in the common predecessor of all archaea.

关键词： G+C 3GC arginine mutational pressure archaea entropy

Topology in Biology: Singularities and Surgery Transformations in Metazoan Dev.lopment and Ev.lution

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Applied Mathematics 2014年第17期5卷 2664-2674页

作者： v.leria v. Isaev. Nickolay v. Kasyanov.eugene v. Presnov A.N. Sev.rtsov.Institute of Ecology and Ev.lution of the Russian Academy of Science Moscow Russia A.v. Zhirmunsky Institute of Marine Biology Far East Branch of Russian Academy of Sciences Vladivostok Russia Institute of Theory and History of Architecture and Town Planning Moscow Russia The v.lcani Center Gilat Israel

The rev.ew presents a topological description and interpretation (analysis) of some ev.nts in metazoan dev.lopment and ev.lution through the use of well-known mathematical concepts and theorems (using topological approach). It is the topological language that can prov.de strict and adequate description of v.rious phenomena in dev.lopmental and ev.lutionary transformations. Topological singularities inev.tably arising and transforming during early dev.lopment destroy the preexisting pattern of symmetry. The symmetry breaking of preexisting spatial pattern plays a critical role in biological morphogenesis in dev.lopment and ev.lution. Some ev.nts of early dev.lopment are interpreted in terms of symmetry breakdown and related to well-known mathematical theorems. A topological inev.tability of some dev.lopmental ev.nts through the use of classical topological concepts is discussed. The topological approach makes it possible to consider the succession of spherical surgeries, which change the topological genus of an animal body surface. We model the biological shape as a set of smooth, closed, oriented surfaces—membrane or epithelial layers. Membrane and epithelial surfaces are boundary layers, interfaces between a liv.ng structure and its env.ronment, ensuring metabolism. Toroid forms as well as fractal structures in metazoans can be considered as functionally optimized biological design and attractors in biological morphogenesis. The epithelial surface is an interface between the internal medium of an organism and the outside env.ronmental medium;topological and fractal transformations during metazoan ev.lution and dev.lopment increase this interface, ensuring better adaptation of organism to the env.ronment. Fractal structures as well as toroid forms can be considered as a functionally optimized design in Metazoa. Topological methodology rev.als a certain set of topological rules constraining and directing biological morphogenesis during ev.lution and dev.lopment.

关键词： Topological Surgery Singularity Symmetry Breakdown Ev.lutionary Biology Embryology

A 96-antenna radioheliograph

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Research in Astronomy and Astrophysics 2014年第7期14卷 864-868页

作者： Sergey v.Lesov.i Alexander T.Altyntsev.eugene F.Iv.nov.Alexey v.Gubin Institute of Solar-Terrestrial Physics

Here we briefly present some design approaches for a multifrequency 96-antenna radioheliograph. The configuration of the array antenna, transmission lines and digital receiv.rs is the main focus of this work. The radioheliograph is a T-shaped centrally condensed radiointerferometer operating in the frequency range 4–8 *** justification for the choice of such a configuration is discussed. The signals from antennas are transmitted to a workroom by analog optical links. The dynamic range and phase errors of the microwav.-ov.r-optical signal are considered. The signals after downconv.rting are processed by digital receiv.rs for delay tracking and fringe stopping. The required step of delay tracking and data rates are considered. Two 3-bit data streams（I and Q） are transmitted to a correlator with the transceiv.rs embedded in Field Programmed Gate Array chips and with PCI Express cables.

关键词： telescopes -- instrumentation: interferometers -- Sun: radio radiation