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1.
Phys Rev Lett ; 128(15): 153602, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35499869

RESUMEN

Coherent quantum systems are a key resource for emerging quantum technology. Solid-state spin systems are of particular importance for compact and scalable devices. However, interaction with the solid-state host degrades the coherence properties. The negatively charged silicon vacancy center in diamond is such an example. While spectral properties are outstanding, with optical coherence protected by the defects symmetry, the spin coherence is susceptible to rapid orbital relaxation limiting the spin dephasing time. A prolongation of the orbital relaxation time is therefore of utmost urgency and has been tackled by operating at very low temperatures or by introducing large strain. However, both methods have significant drawbacks: the former requires use of dilution refrigerators and the latter affects intrinsic symmetries. Here, a novel method is presented to prolong the orbital relaxation with a locally modified phonon density of states in the relevant frequency range, by restricting the diamond host to below 100 nm. Subsequently measured coherent population trapping shows an extended spin dephasing time compared to the phonon-limited time in a pure bulk diamond. The method works at liquid helium temperatures of few Kelvin and in the low-strain regime.

2.
Biofizika ; 60(2): 337-42, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26016030

RESUMEN

We consider the propagation of autowaves in the moving liquid excitable medium. The shapes of the autowave fronts in cases of the Poiseuille and Couette flows are determined in flat capillaries within a kinematic approach. We show the existence of a critical velocity for the flows above which the autowave fronts should break off. The possibility of a diode effect--the one-way capillary conductivity--is studied. The results of computer simulations are in good agreement with the theoretical predictions.


Asunto(s)
Capilares/fisiología , Modelos Biológicos , Viscosidad , Fenómenos Biomecánicos , Simulación por Computador , Difusión
3.
Prikl Biokhim Mikrobiol ; 43(1): 102-8, 2007.
Artículo en Ruso | MEDLINE | ID: mdl-17345867

RESUMEN

The effects of intercultivar substitution of individual chromosome pairs (except for 1B, 6D, and 7A) in the wheat cultivars Saratovskaya 29 and Janetzkis Probat, differing in quality, on specific lipoxygenase activity, the grain yield per spike, and the main technological properties of flour and dough were studied. It was demonstrated that the substitution of individual chromosomes of the recipient cultivar Saratovskaya 29 with the homologous chromosomes of the donor cultivar Janetzkis Probat caused significant changes in lipoxygenase activity and several other quality characteristics. The correlations between the lipoxygenase activity and the parameters of physical dough properties were determined. Three molecular forms of lipoxygenase (Lpx-1, Lpx-2, and Lpx-3), differing in the value of surface charge and enzymatic activity, were detected by native PAGE.


Asunto(s)
Cromosomas de las Plantas/genética , Harina , Lipooxigenasa/metabolismo , Proteínas de Plantas/genética , Triticum/genética , Cruzamientos Genéticos , Activación Enzimática , Isoenzimas/genética , Isoenzimas/metabolismo , Lipooxigenasa/genética , Proteínas de Plantas/metabolismo , Triticum/enzimología
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 66(3 Pt 2A): 036207, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12366224

RESUMEN

The evolution of excitation wave fronts in a spatially modulated light-sensitive Belousov-Zhabotinsky system is investigated experimentally and theoretically. The excitation wave propagates in a thin, quasi-two-dimensional reaction layer, which is illuminated through a periodical gray level mask. The light-induced differences in excitability and velocity give rise to a temporal and spatial modulation of the initially flat fronts. The experimental front evolution is described in the framework of a kinematical theory as developed earlier for nonuniformly curved systems.

5.
Med Tekh ; (2): 34-6, 1979.
Artículo en Ruso | MEDLINE | ID: mdl-431361

RESUMEN

The results of investigations made by the authors showed that the signal spectra of the bioelectrical and mechanical activity of the ureteral smooth muscles lie within the range of 0.05--1 Hz. The developed devices for registration of electro-and dynamograms of ureters may be utilized in investigating the functional state of the urinary system of the organism.


Asunto(s)
Electrodiagnóstico/instrumentación , Uréter/fisiopatología , Urodinámica , Potenciales de Acción , Humanos , Cateterismo Urinario , Enfermedades Urológicas/diagnóstico
6.
Aviakosm Ekolog Med ; 33(6): 36-8, 1999.
Artículo en Ruso | MEDLINE | ID: mdl-10656133

RESUMEN

The mechanism of Ukhtomskii's dominant was used to improve operator's performance activity. Recognition of visual images--obscured Arabic numerals--in a sensorially rich environment (classic or rock music records) turned to be more successful: time of the task was reduced and the probability of correct identification increased. A reverse U-shaped dependence between the intensity of music and identification was stated. Repetition of music fragments at a constant value marred the positive effect.


Asunto(s)
Ambiente Controlado , Actividad Nerviosa Superior/fisiología , Sensación/fisiología , Humanos , Música , Estimulación Luminosa/instrumentación , Estimulación Luminosa/métodos , Tiempo de Reacción/fisiología , Percepción Visual/fisiología
10.
J Biol Phys ; 25(2-3): 87-100, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23345690

RESUMEN

We study theoretical and numerical propagation of autowave fronts in excitable two-variable (activator-inhibitor) systems with anisotropic diffusion. A general curvature-velocity relation is derived for the case that the inhibitor diffusion is neglected. This relation predicts the break of an activation front when the front curvature exceeds a critical value, which is corroborated by computer simulations of a particular reaction-diffusion model. Some qualitative effects associated with the inhibitor diffusion are studied numerically. It is found that the critical value of curvature decreases with an increase in the inhibitor diffusion coefficient. The core of a spiral wave increases in size and turns through an angle which depends on the inhibitor diffusion coefficient. PACS Numbers: 05.50. +q, 05.70. Ln., 82.40. -g, 87.10. +e.

11.
Antibiotiki ; 25(8): 626-9, 1980 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-7406476

RESUMEN

Twenty five children suffering from acute and chronic hematogenic osteomyelitis were subjected to lincomycin therapy in addition to surgical and general tonic treatment. The antibiotic was administered by means of electrophoresis in 15 children and by means of electrophoresis together with intramuscular injections in 10 children. It was found that administration of the drug by means of electrophoresis 1 hour after its intramuscular injection provided the highest lincomycin levels in the bone cavity favourable for the disease treatment.


Asunto(s)
Iontoforesis , Lincomicina/metabolismo , Osteomielitis/metabolismo , Adolescente , Huesos/metabolismo , Niño , Preescolar , Humanos , Lincomicina/administración & dosificación , Osteomielitis/tratamiento farmacológico , Factores de Tiempo , Distribución Tisular
12.
Nature ; 413(6857): 716-8, 2001 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-11607027

RESUMEN

The discovery of nanostructured forms of molecular carbon has led to renewed interest in the varied properties of this element. Both graphite and C60 can be electron-doped by alkali metals to become superconducting; transition temperatures of up to 52 K have been attained by field-induced hole-doping of C60 (ref. 2). Recent experiments and theoretical studies have suggested that electronic instabilities in pure graphite may give rise to superconducting and ferromagnetic properties, even at room temperature. Here we report the serendipitous discovery of strong magnetic signals in rhombohedral C60. Our intention was to search for superconductivity in polymerized C60; however, it appears that our high-pressure, high-temperature polymerization process results in a magnetically ordered state. The material exhibits features typical of ferromagnets: saturation magnetization, large hysteresis and attachment to a magnet at room temperature. The temperature dependences of the saturation and remanent magnetization indicate a Curie temperature near 500 K.

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