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Human enamel thickness and ENAM polymorphism

International Journal of Oral Science 2016年第2期8卷 93-97页

作者： Diane M Daubert Joanna L Kelley yuriy g udod Carolina Habor Chris g Kleist Ilona K Furman Igor N Tikonov Willie J Swanson Frank A Roberts Department of Periodontics University of Washington Center for Reproductive Biology and School of Biological Sciences Washington State University Department of Oral and Maxillofacial Surgery University of Texas Southwestern Medical Center Department of genome Sciences University of Washington

The tooth enamel development gene, enamelin （ENAM）, showed evidence of positive selection during a genome-wide scan of human and primate DNA for signs of adaptive evolution. The current study examined the hypothesis that a single-nucleotide polymorphism （SNP） C14625T （rs7671281） in the ENAM gene identified in the genome-wide scan is associated with a change in enamel phenotype. African Americans were selected as the target population, as they have been reported to have a target SNP frequency of approximately 50%, whereas non-Africans are predicted to have a 96% SNP frequency. Digital radiographs and DNA samples from 244 teeth in 133 subjects were analysed, and enamel thickness was assessed in relation to SNP status, controlling for age, sex, tooth number and crown length. Crown length was found to increase with molar number, and females were found to have thicker enamel. Teeth with larger crowns also had thicker enamel, and older subjects had thinner enamel. Linear regression and generalized estimating equations were used to investigate the relationship between enamel thickness of the mandibular molars and ENAM SNP status; enamel in subjects with the derived allele was significantly thinner （P= 0.040） when the results were controlled for sex, age, tooth number and crown length. The derived allele demonstrated a recessive effect on the phenotype. The data indicate that thinner dental enamel is associated with the derived ENAM genotype. This is the first direct evidence of a dental gene implicated in human adaptive evolution as having a phenotypic effect on an oral structure.

关键词： enamel genetics polymorphisms tooth development

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Dependence of the E. coli promoter strength and physical parameters upon the nucleotide sequence

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第11期6卷 1063-1068页

作者： BEREZHNOY AndreyY. SHCKORBATOV yuriy g. National Scientific Center Kharkov Physical-Technical Institute Kharkov 61108 UkraineInstitute of Biology Kharkov National University Kharkov 61077 Ukraine

The energy of interaction between complementary nucleotides in promoter sequences of E. coli was calculated and visualized. The graphic method for presentation of energy properties of promoter sequences was elaborated on. Data obtained indicated that energy distribution through the length of promoter sequence results in picture with minima at –35, –8 and +7 regions corresponding to areas with elevated AT (adenine-thymine) content. The most important difference from the random sequences area is related to –8. Four promoter groups and their energy properties were revealed. The promoters with minimal and maximal energy of interaction between complementary nucleotides have low strengths, the strongest promoters correspond to promoter clusters characterized by intermediate energy values.

关键词： DNA sequence Promoter strength Nucleotide pair energy -35 sequence -10 sequence +7 sequence

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Trilayer anisotropic structure versus randomly oriented structure in heart valve leaflet tissue engineering

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Bio-Design and Manufacturing 2023年第4期6卷 423-438页

作者： yuriy Snyder Soumen Jana Department of Bioengineering University of MissouriColumbiaMO 65211USA

It has been hypothesized that leaflet substrates with a trilayer structure and anisotropicmechanical properties could be useful for the production of functional and long-lasting tissue-engineered *** investigate the influence of the anisotropic structural and mechanical characteristics of a substrate on cells,in this study,we electrospun trilayer anisotropic fibrous substrates and randomly oriented isotropic fibrous substrates(used as controls)from polycaprolactone ***,the random substrates had higher radial and lower circumferential tensile properties than the trilayer substrates;however,they had similar flexural *** valvular interstitial cells cultured on both substrates produced random and trilayer cell-cultured constructs,*** trilayer cell-cultured constructs had more anisotropic mechanical properties,17%higher cellular proliferation,14%more extracellular matrix(i.e.,collagen and glycosaminoglycan)production,and superior gene and protein expression,suggesting that more cells were in a growth state in the trilayer constructs than in the random ***,the random and radial layers of the trilayer constructs had more vimentin,collagen,transforming growth factor-beta 1(TgF-ß1),transforming growth factor-beta 3(TgF-ß3)gene expression than in the circumferential layer of the *** study verifies that the differences in structural,tensile,and anisotropic properties of the trilayer and random substrates influence the characteristics of the cells and ECM in the constructs.

关键词： Heart valve leaflet Trilayer Tissue engineering Fiber Electrospinning

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geothermal Model of the Fore-Yenisey Sedimentary Basin——Transitional Structure between the Ancient Siberian Platform and the Young West Siberian Plate

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Acta geologica Sinica(English Edition) 2022年第2期96卷 582-590页

作者： Dmitriy NOVIKOV Fedor DULTSEV yuriy FILIPPOV Trofimuk Institute of Petroleum geology and geophysics SB RASNovosibirsk 630090Russia Novosibirsk State University Novosibirsk 630090Russia

Results of the investigation into the geothermal regime of the Fore-Yenisey sedimentary basin, formed during the collision and subsidence of the Kas-Turukhan microcontinent and the western margin of the Siberian craton in the late Neoproterozoic and early Paleozoic are reported. It was established that the structural and geothermal conditions of the upper Precambrian–Paleozoic sections are similar to those in the western regions of the Siberian platform and are characterized by rather low geothermal gradients(12.5–25.5 ℃/km). In the western parts of the basin, formation temperatures in the uppermost pre-Jurassic sediments are 50℃–85℃, decreasing eastward to 30℃–55℃. For the first time, the detailed geothermal model of the basin sedimentary fill was developed. This model allows predictions of the geothermal conditions of Earth’s interior.

关键词： geothermal model formation temperature Fore-Yenisey sedimentary basin West Siberia

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Regularities in the E. coli promoters composition in connection with the DNA strands interaction and promoter activity

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第12期7卷 969-973页

作者： BEREZHNOY Andrey Yu SHCKORBATOV yuriy g. HISANORI Kiryu National Scientific Center Kharkov Physical-Technical Institute Kharkov 61108 Ukraine Institute of Biology Kharkov National University Maidan Svobody 4 Kharkov 61077 Ukraine Computational Biology Research Center National Institute of Advanced Industrial Science and Technology Koto-ku Tokyo 135-0064 Japan)

The energy of interaction between DNA strands in promoters is of great functional importance. Visualization of the energy of DNA strands distribution in promoter sequences was achieved. The separation of promoters in groups by their energetic properties enables evaluation of the dependence of promoter strength on the energetic properties. The analysis of groups (clusters) of promoters distributed by the energy of DNA strands interaction in ?55, ?35, ?10 and +6 sequences indicates their connection with the transcriptional activity.

关键词： DNA sequence Promoter strength DNA chains interaction energy DNA sequences classification

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Influence of polyolefin fibers on the strength and deformability properties of road pavement concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第4期6卷 407-417页

作者： Olga Smirnova Alexey Kharitonov yuriy Belentsov Department of Constructing Mining Enterprises and Underground Structures Saint-Petersburg Mining UniversitySaint Petersburg 199106Russia Department of Technology of Building Materials and Metrology Saint-Petersburg State University of Architecture and Civil EngineeringSaint Petersburg 190005Russia Department of Building Materials and Technologies Emperor Alexander I St.Petersburg State Transport UniversitySaint Petersburg 190031Russia

Influence of the type and quantity of polyolefin fibers on the strength properties(compression strength, tensile strength in bending, strength in uniaxial tension), the deformation properties(elastic modulus, Poisson’s coefficient) and the abrasion resistance of cement concrete with water-to-cement ratio within 0.31 e0.55 were stated in the *** ways of fibers introduction into fresh concrete were investigated. It was shown that the fibers introduction method and procedure of mixing are the ways to improve the fibers uniform distribution in fresh concrete. The increase of the bending tensile strength and the uniaxial tensile strength of concrete with fibers reinforcement in comparison with the reference concrete was observed with the water-to-cement ratio decrease. The increase of uniaxial tensile strength at age of 28 days for concrete with macrofibers in amount of4.5 kg/m^3 was 23% and 29%;for macrofibers in quantity of 3 kg/m^3 was 19% and 26% with water-cement ratio equal to 0.49 and 0.31, respectively. The maximum reduction of abrasion in the range of 7.5%e10% was observed in concrete with water-to-cement ratio within0.44 e0.55 for all investigated types of fibers. The influence of fibers on the concrete abrasion with lower W/C ratio was negligible. The results can contribute to the rational use of modified polyolefin fibers in road pavement concrete.

关键词： Road pavement concrete Polyolefin fibers Strength Elastic modulus Abrasion Water-to-cement ratio

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Optical absorption and photoelectron collection properties of silicon wafers with conical quantum nanocrystals structure

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Nano-Micro Letters 2010年第3期2卷 149-153页

作者： yuriy Vashpanov Jae-Il Jeong Electrical and Computer Engineering Division of Hanyang Institute of Technology Hanyang University

A conical form of nano-sized quantum cluster was formed on the surface of p-type crystalline silicon [111] wafer by anode electrochemical etching in HF-based *** conical surface is highly effective in absorbing sunlight and transporting photoelectrons to semiconductor *** are because each cone has a graded band gap with the energy level in the range from 1.1 to 3 eV which can be considered as consisting of quantum dots in different *** the boron concentration on the surface of each cone gradually decreases from top to bottom,a continuously varying electrical field is created along the cone *** electric field is forcing photoelectrons generated in the cone to move rapidly to the direction perpendicular to wafer *** the drift time of photoelectrons can be less than their recombination time within the thin layer close to the bottom of the cone.

关键词： Silicon Nanocrystals Electrochemical etching Solar cells

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Ectomycorrhiza of Larix sibirica Ledeb. along the gradients of main ecological factors and elevation at the Northern and Subpolar Urals

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Journal of Mountain Science 2018年第12期15卷 2603-2613页

作者： SIZONENKO Tatyana Alexandrovna DUBROVSKIY yuriy Alexandrovich Institute of Biology of Komi Scientific Centre of the Ural Branch of the Russian Academy of Sciences Russia SyktyvkarKommunistieheskaya str28Syktyvkar167000Russian Federation

Siberian larch(Larix sibirica Ledeb.) forests cover the largest areas in the Eurasian boreal zone, but there are insufficient data on its root system including the structure and functional traits of ectomycorrhizas(EM). The aim of this research is to find out if the morphological parameters of Larix sibirica EMs responded to the changes in elevation and main ecological factors(soil humidity, soil richness, soil acidity and habitat illumination). Using light microscopy, we studied EM diameter, root diameter, mantle width, and mantle volume share, share of tannin cells layers, EM density and EM length of Larix sibirica in two main types of plant communities along the elevation gradient at the Northern and Subpolar Urals. Differences in the environment were traced using phytoindication approach and the Ellenberg ecological scales. All the studied traits depend on the elevation and studied ecological factors. The diversity of fungal mantles is low, and the proportion of unstructured and pseudoparenchymatous mantles is high in response to the deterioration of the humidity, soil nitrogen content and acidity at higher-altitude habitats. Results of EM quantitative parameters measurements confirmed this pattern. We found a decline in the EM linear dimensions accompanied by a compensatory growth of the EM density with the raised elevation and the deterioration of environmental conditions.

关键词： Ectomycorrhiza Larix sibirica Anatomy Fungal mantles diversity Elevation Urals

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Thermal Stresses and Theorem on Decomposition

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Transactions of Nanjing University of Aeronautics and Astronautics 2014年第2期31卷 175-179页

作者： Valeriy Lokhov yuriy Nyashin Department of Theoretical Mechanics and Biomechanics Perm National Research Polytechnic University

The thermal expansion strain is considered as a special case of *** authors proved the theorem on decomposition of eigenstrain existing in a body into two constituents:Impotent eigenstrain(not causing stress in any point of a body)and nilpotent eigenstrain(not causing strain in any point of a body).According to this theorem,the thermal stress can be easily found through the nilpotent *** the eigenstrain is an impotent one,the thermal stress *** this case,the eigenstrain must be *** authors suggest a new approach to measure of eigenstrain incompatibility and hence to estimate of thermal stresses.

关键词： eigenstrain thermal stresses decomposition impotent eigenstrain nilpotent eigenstrain functional space

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The vertical structure of the vegetative canopy of the brown algae Cystoseira(Black Sea)

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Journal of Oceanology and Limnology 2020年第1期38卷 124-132页

作者： ALEXSANDR VPRAZUKIN yuriy KFIRSOV YURY KAMENIR The A.O.Kovalevsky Institute of Marine Biological Researches Russian Academy of SciencesSevastopol 299011Russia The Mina&Everard goodman Faculty of Life Sciences Bar-Ilan UniversityRamat-Gan 5290002Israel

In the coastal ecosystems of the Black Sea,macrophytobenthos and,in particular,the association of Cystoseira crinite,***,Cladostephus verticillatus,and Corallina mediterranea,with its thick vegetative canopy(VC),is the key contributor to primary production(PP).Though the vertical structure of the canopy,formed by the algal association,is of principal importance to the PP level,this subject has been long-neglected by *** goal of our work was to compare vertical structures of the vegetative canopy of Cystoseira brown algae under diverse hydrodynamical conditions of the Crimean Peninsula *** were collected using the 50 cm×50 cm counting frame at eight stations positioned in shallow(55-60 cm deep)sites of Sevastopol Bay(Crimean Peninsula).Dry weight biomass of the VC was determined for all algae assemblage and for each algal species individually,per horizontal surface unit,at each height(Z).The study shows that:1)the VC is characterized by unimodal vertical distribution of biomass,with maximum estimate in the lower part,where the biomass increases to 85%of the total biomass;2)a series of single-peaked curves reliably describes the unimodal distribution of the biomass;thalli of different age groups are found along the canopy profile;and 3)algae found in epiphytic synusia prefer inhabiting the upper part of the *** role of environmental factors(seawater turbulence and solar radiation)is discussed in reference to the formation of the vertical structure,made up of the associations of the brown algae Cystoseira.

关键词： vertical structure of the canopy phytobenthos phytocenosis Cystoseira epiphyte biomass multicellular algae Black Sea

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