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1.
J Chem Phys ; 122(21): 214726, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15974781

RESUMO

An analytic expression for the electromagnetic enhancement of the spontaneous emission rate and Raman scattering cross-section for an excited atom or molecule in close proximity to a metal nanocylinder has been derived by quantum theory. Coupling of the atomic or molecular optical radiation into the TM0 surface plasmon mode of the nanocylinder results in reradiation by the cylinder, a process that is most efficient when the incident radiation is linearly polarized, with the electric field oriented parallel to the axis of the nanocylinder. For a silver cylinder having a radius and length of 5 and 20 nm, respectively, the enhancement in the spontaneous emission rate is >10(7) for variant Planck's over 2pi omega0 approximately 2.4 eV (lambda=514 nm), which corresponds to an increase of approximately 10(14) in the Raman scattering cross section. This result, as well as the prediction that the atomic dipole generates broadband, femtosecond pulses, are in qualitative agreement with previously reported experiments involving metal nanoparticle aggregates. The theoretical results described here are expected to be of value in guiding future nonlinear optical experiments in which carbon nanotubes or metal nanowires with controllable physical and electrical characteristics are patterned onto a substrate and coupled with emitting atoms or molecules.

2.
Artigo em Russo | MEDLINE | ID: mdl-15554306

RESUMO

The strategy of the adaptation of S. typhimurium population to water environment under the influence of temperature factor was studied by scanning electron microscopy. Salmonellae were found to adhere to the surface of the Daphnia chitin covering. The study revealed that S. typhimurium population existed in water in the form of covered microcolonies as well as in the form of spheroplast-type cells and small cells in the L-form, joined with bands. The viability of salmonellae in water environment was studied without interaction and following interaction with Daphnia.


Assuntos
Daphnia/microbiologia , Ecossistema , Formas L/fisiologia , Salmonella typhimurium/fisiologia , Adaptação Fisiológica , Animais , Aderência Bacteriana , Quitina/química , Daphnia/química , Formas L/crescimento & desenvolvimento , Formas L/isolamento & purificação , Formas L/ultraestrutura , Microscopia Eletrônica , Salmonella typhimurium/crescimento & desenvolvimento , Salmonella typhimurium/ultraestrutura , Temperatura , Fatores de Tempo , Microbiologia da Água
3.
Opt Lett ; 26(7): 408-10, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18040336

RESUMO

A novel analytical treatment of the transport of broadband radiation arbitrarily directed through a bleaching medium is presented. The emphasis is on the principle features of photodecomposition (bleaching) wave formation. Considering radiation from a uniform planar source with stable radiative characteristics and media with a uniform initial distribution of the absorptive component, we show that this problem has an asymptotic stationary solution for a wave propagating through a medium characterized by a photodecomposition spectrum without any portion in which the absorption cross section continually runs down to zero.

5.
Ross Med Zh ; (2): 6-8, 1992.
Artigo em Russo | MEDLINE | ID: mdl-1643345

RESUMO

Radionuclide study of ejection fraction of the right heart ventricle was carried out in lung tuberculosis patients with respiratory insufficiency and cor pulmonale. Oxygen therapy was found to promote reduction of right ventricle heart failure in effective treatment of lung tuberculosis. The greatest reduction of heart failure was recorded in cases where oxygen therapy was combined with cardiac glycosides. As the tuberculosis process progresses, oxygen therapy does not decrease right ventricle heart failure. The treatment by antibacterial agents alone without using oxygen does not lead to the rise of ejection fraction of the right ventricle of the heart.


Assuntos
Oxigenoterapia , Volume Sistólico , Tuberculose Pulmonar/terapia , Antituberculosos/uso terapêutico , Glicosídeos Cardíacos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Doença Cardiopulmonar/tratamento farmacológico , Doença Cardiopulmonar/etiologia , Doença Cardiopulmonar/fisiopatologia , Ventriculografia com Radionuclídeos , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Tuberculose Pulmonar/complicações
6.
Khirurgiia (Mosk) ; (10): 44-8, 1989 Oct.
Artigo em Russo | MEDLINE | ID: mdl-2593573

RESUMO

The authors analysed 368 clinical cases with gastroduodenal hemorrhages. The changes in blood microcirculation and nonspecific immunity were studied in 62 patients. They proposed a method of complex nonoperative treatment of gastrointestinal hemorrhages, including ganglionic block, which made it possible not only to reduce the operative activity but also to achieve epithelialization of ulcers in patients with peptic ulcer. As the result of the study, a unique classification of the severity of blood loss is suggested which is based on the degree of deviation off the tests studied from the normal values. If gastroduodenal hemorrhage continues, an operation is recommended, the character of which is determined by the patient's age, the severity of blood loss, and the source of bleeding and its localization.


Assuntos
Úlcera Péptica Hemorrágica/cirurgia , Úlcera Duodenal/complicações , Feminino , Humanos , Masculino , Métodos , Microcirculação , Úlcera Péptica Hemorrágica/etiologia , Úlcera Péptica Hemorrágica/fisiopatologia , Úlcera Gástrica/complicações
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