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1.
Izv Akad Nauk Ser Biol ; (5): 477-86, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26638235

RESUMO

A comparative study of yellow-anthered and red-anthered forms of Scots pine, growing in hydrothermally contrasting bog and upland ecotopes, was performed by karyological traits and nuclear DNA content. Some differences were revealed between yellow-anthered and red-anthered forms of pine as components of intraspecific diversity in'the frequency of occurrence of violations in the number of chromosomes, chromosome sizes (total length of diploid set, absolute and relative lengths), the centromeric index, the localization of secondary constrictions in chromosomes, and the amount of DNA.


Assuntos
Núcleo Celular/genética , Cromossomos de Plantas/genética , DNA de Plantas/genética , Pinus/genética , Característica Quantitativa Herdável
2.
Tsitol Genet ; 48(3): 30-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25016826

RESUMO

Investigations on B chromosomes found for the first time for Picea abies (L.) H. Karst. have been conducted. Seeds of Picea abies from two populations of Western Rhodopes (Bulgaria) located at the southern border of species range, and protected according to Bern Convention and EC Habitat Directive were collected for this study. Mixoploidy was detected in some germinating seeds of Picea abies. It was found that metaphase cells of germinating seeds contain 0-4 B chromosomes of both metacentric and submetacentric types. The variability of B chromosomes number and their occurrence was observed. Along with B chromosomes, some chromosome aberrations such as fragments and ring chromosomes were revealed in metaphase cells of Picea abies from studied populations. The possible adaptive role of B chromosomes presence for Picea spp. is discussed.


Assuntos
Aberrações Cromossômicas , Cromossomos de Plantas/genética , Picea/crescimento & desenvolvimento , Picea/genética , Sementes , Bulgária , Germinação/genética , Metáfase/genética , Picea/ultraestrutura , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/ultraestrutura , Árvores
3.
Izv Akad Nauk Ser Biol ; (5): 510-7, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25720290

RESUMO

Cytogenetic studies on three species of submerged plants from different parts of the Yenisei river area subjected to radioactive impact of the Krasnoyarsk Mining-and-Chemical Plant and the Electrochemical Factory have been conducted. A high level of irregularities in anatelophase and metaphase of mitoses has been revealed in test samples compared to the control: agglutination and fragmentation of chromosomes, lagging chromosomes, bridges, fragments, misdivisions, and others. The natuie of the disorders indicates that they are related in part to the direct damage to the chromosome structure and in part to damage to the spindle.


Assuntos
Cromossomos de Plantas/genética , Hydrocharitaceae/genética , Resíduos Radioativos , Poluentes Radioativos da Água , Animais , Cromossomos de Plantas/efeitos da radiação , Hydrocharitaceae/efeitos da radiação , Mitose/genética , Mitose/efeitos da radiação , Rios , Federação Russa
4.
Genetika ; 50(9): 1059-66, 2014 Sep.
Artigo em Russo | MEDLINE | ID: mdl-25735136

RESUMO

We evaluated the population structure of the bog and dry land populations of the Siberian pine Pinus sibirica (P. sibrica) in Western Siberia using nuclear genome markers. Six pairs of nuclear microsatellite loci were used for this analysis. We detected 30 allelic variants in 120 individuals of four populations of P. Sibirica. We established that the studied populations differ by genetic structure. The most essential differences were identified between the Siberian pine population from oligotrophic bog and the group of populations from dry land within eutrophic bogs and near settlements P. sibirica forest (F(ST) = 0.019; D(N) = 0.053). We estimated that diversification of the West Siberian populations of P. sibirica exceeded 2.4% (F(ST) = 0.024), based on an analysis of SSR markers.


Assuntos
Loci Gênicos , Variação Genética , Repetições de Microssatélites , Pinus/genética , Sibéria
5.
Izv Akad Nauk Ser Biol ; (4): 417-22, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20799642

RESUMO

Chromosomal mutations and mixoploidy have been revealed in the seedlings of Scotch pine (Pinus sylvestris) growing in a hydromorphic environment. A giant chromosome was detected for the first time in gymnosperms.


Assuntos
Cromossomos de Plantas/genética , Pinaceae/genética , Cromossomos de Plantas/ultraestrutura , Mutação , Poliploidia , Cromossomos em Anel , Sibéria
6.
Izv Akad Nauk Ser Biol ; (2): 244-7, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17668465

RESUMO

Chromosomal mutations were studied in the Norilsk population of Siberian larch (Larix sibirica Ledeb.) growing at the northeastern boundary of the species range affected by airborne smelter emissions. Different types of frequent chromosomal mutations have been revealed in the Norilsk population of L. sibirica and B-chromosomes have been found in this species for the first time.


Assuntos
Aberrações Cromossômicas , Cromossomos de Plantas/genética , Larix/genética , Sibéria
7.
Radiats Biol Radioecol ; 47(1): 63-73, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17387996

RESUMO

The study was devoted to investigation of the contents of radionuclides and of heavy metals and to evaluate the frequency of chromosomal aberrations in samples of Elodea canadensis, a submerged plant, collected in different parts of the Yenisei River. The samples were collected in the area subjected to radioactive impact of the Mining-and-Chemical Combine (MCC) at Zheleznogorsk and in the control area, upstream of the MCC. The investigations shown that elodea biomass in the area affected by MCC operation contained a long inventory of artificial radionuclides typical for the MCC discharges. The upstream of the MCC, in the control sampling area, the sediments and the elodea biomass contained only one artificial radionuclide--137Cs. Thus, the exposure doses to elodea shoots and roots upstream of the MCC are small (not more than 8 microGy/d) and the main contribution info the dose is made by natural radionuclides. At the MCC discharge site (the village of Atamanovo) and at the downstream of it, the total dose rate increases almost an order of magnitude, reaching its maximal values--72 microGy/d for elodea shoots and 58 microGy/d for its roots. Cytogenetic investigations of elodea roots shown that at the MCC discharge site (the village of Atamanovo) and at downstream of it the occurrence of chromosomal aberrations in ana-telophase and in metaphase cells of elodea was considerably higher than in the control area. It is highly probable that this simultaneous dramatic increase in the total exposure rate and the occurrence of chromosomal aberrations in elodea is associated with the radiation factor. It is suggested that elodea is affected not only by the radiation factor but also by the chemical factor--toxicity of heavy metals.


Assuntos
Indústria Química , Hydrocharitaceae/química , Monitoramento de Radiação , Rios/química , Poluentes Radioativos da Água/análise , Poluição da Água , Radioisótopos de Césio/análise , Radioisótopos de Césio/toxicidade , Aberrações Cromossômicas , Análise Citogenética , Variação Genética , Sedimentos Geológicos/química , Hydrocharitaceae/genética , Hydrocharitaceae/efeitos da radiação , Metais Pesados/análise , Metais Pesados/toxicidade , Raízes de Plantas/citologia , Raízes de Plantas/genética , Doses de Radiação , Sibéria , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Poluentes Radioativos da Água/toxicidade
8.
Phys Rev Lett ; 94(22): 227003, 2005 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-16090428

RESUMO

The influence of magnetic Ni and nonmagnetic Zn impurities on the normal-state pseudogap (PG) in the c-axis optical conductivity of (Sm,Nd)Ba(2){Cu(1-y)(Ni,Zn)(y)}(3)O(7-delta) crystals was studied by spectral ellipsometry. We find that these impurities, which strongly suppress superconductivity, have a profoundly different impact on the PG. Zn gives rise to a gradual and inhomogeneous PG suppression while Ni strongly enhances the PG. Our results challenge theories that relate the PG either to precursor superconductivity or to other phases with exotic order parameters, such as flux phase or d-density wave states, that should be suppressed by potential scattering. The apparent difference between magnetic and nonmagnetic impurities instead points towards an important role of magnetic correlations in the PG state.

9.
Phys Rev Lett ; 93(16): 167003, 2004 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-15525022

RESUMO

Using spectral ellipsometry, we measured the dielectric function of a Na(0.82(2))CoO2 crystal that exhibits bulk antiferromagnetism with T(N)=19.8 K. We identify two prominent transitions as a function of temperature. The first one at 280 K involves marked changes of the electronic and lattice responses that are indicative of charge ordering in the CoO2 layers. The second transition occurs around T(N)=19.8 K and reveals sizable spin-charge coupling. The data are discussed in terms of charge ordering and formation of magnetopolarons due to a charge-induced spin-state transition of adjacent Co3+ ions.

10.
Phys Rev Lett ; 92(3): 037202, 2004 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-14753902

RESUMO

The electronic and magnetic properties of SrFeO(3-delta) single crystals with controlled oxygen content (0< or =delta< or =0.19) have been studied systematically by susceptibility, transport, and spectroscopic techniques. An intimate correlation between the spin-charge ordering and the electronic transport behavior is found. Giant negative as well as positive magnetoresistance are observed.

11.
Tsitologiia ; 45(5): 515-20, 2003.
Artigo em Russo | MEDLINE | ID: mdl-14521060

RESUMO

Results of chromosome mutation investigation in Abies sibirica populations growing in fen and dry valley in Western Siberia are presented. The frequency of chromosome aberrations and mitotic irregularities is higher in dry valley population of the fir, than in its fen population. However, the spectrum of abnormalities registered in metaphase and ana-telophase cells of the fir from fen is broader, compared to that from dry valley. These features may be due to the fir genome reorganization in different environmental conditions, and indicate the plant reaction to stress factors.


Assuntos
Abies/genética , Cromossomos de Plantas , Ecologia , Mutação , Sibéria
12.
Phys Rev Lett ; 89(27): 277001, 2002 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-12513232

RESUMO

The far-infrared (FIR) c axis conductivity of a Bi2223 crystal has been measured by ellipsometry. Below T(c) a strong absorption band develops near 500 cm(-1), corresponding to a transverse Josephson plasmon. The related increase in FIR spectral weight leads to a giant violation of the Ferrell-Glover-Tinkham sum rule. The gain in c axis kinetic energy accounts for a sizable part of the condensation energy. We also observe phonon anomalies which suggest that the Josephson currents lead to a drastic variation of the local electric field within the block of closely spaced CuO2 planes.

13.
Vestn Khir Im I I Grek ; 143(9): 104-7, 1989 Sep.
Artigo em Russo | MEDLINE | ID: mdl-2617761

RESUMO

A comparative analysis of effectiveness of anti-ischemic defense of the myocardium performed in operations on the heart in 128 patients has shown that use of ion-balanced solutions is preferential since it allows reducing intrahospital lethality related with acute cardiac insufficiency from 13.3% to 6.3%.


Assuntos
Soluções Cardioplégicas/administração & dosagem , Eletrólitos/administração & dosagem , Parada Cardíaca Induzida , Cardiopatias/cirurgia , Adolescente , Adulto , Cálcio/administração & dosagem , Humanos , Isquemia/prevenção & controle , Magnésio/administração & dosagem , Pessoa de Meia-Idade , Potássio/administração & dosagem , Sódio/administração & dosagem
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