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1.
J Phys Condens Matter ; 33(3): 034003, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33078713

RESUMO

In this paper, we simulate the nucleation and growth of crystalline nuclei in a molybdenum film cooled at different rates confined between two amorphous walls. We also compare the results for the wall-confined and wall-free systems. We apply the same methodology as in the work (Kirova and Pisarev 2019 J. Cryst. Growth 528 125266) which is based on reconstructing the probability density function for the largest crystalline nucleus in the system. The size of the nucleus and the asphericity parameter are considered as the reaction coordinates. We demonstrate that in both the free and confined systems there are two mechanisms of crystal growth: the attachment of atoms to the biggest crystal from the amorphous phase and the merging of the biggest crystal cluster with small ones (coalescence). We show that the attachment mechanism is dominant in the melt cooled down at a slower rate, and the mechanism gradually shifts to coalescence as cooling rate increases. We also observe the formation of long-lived crystal clusters and demonstrate that amorphous walls do not affect their geometric characteristics. However, system confined between walls demonstrates higher glass-forming ability.

2.
Plant Biol (Stuttg) ; 13(5): 767-76, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21815981

RESUMO

Because of their unique tolerance to desiccation, the so-called resurrection plants can be considered as excellent models for extensive research on plant reactions to environmental stresses. The vegetative tissues of these species are able to withstand long dry periods and to recover very rapidly upon re-watering. This study follows the dynamics of key components involved in leaf tissue antioxidant systems under desiccation in the resurrection plant Haberlea rhodopensis and the related non-resurrection species Chirita eberhardtii. In H. rhodopensis these parameters were also followed during recovery after full drying. A well-defined test system was developed to characterise the different responses of the two species under drought stress. Results show that levels of H2O2 decreased significantly both in H. rhodopensis and C. eberhardtii, but that accumulation of malondialdehyde was much more pronounced in the desiccation-tolerant H. rhodopensis than in the non-resurrection C. eberhardtii. A putative protective role could be attributed to accumulation of total phenols in H. rhodopensis during the late stages of drying. The total glutathione concentration and GSSG/GSH ratio increased upon complete dehydration of H. rhodopensis. Our data on soluble sugars suggest that sugar ratios might be important for plant desiccation tolerance. An array of different adaptations could thus be responsible for the resurrection phenotype of H. rhodopensis.


Assuntos
Glutationa/metabolismo , Magnoliopsida/metabolismo , Fenóis/metabolismo , Aclimatação , Antioxidantes/metabolismo , Metabolismo dos Carboidratos , Craterostigma/metabolismo , Desidratação/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo
3.
Chem Pharm Bull (Tokyo) ; 44(12): 2338-9, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8996867

RESUMO

It has been proposed that the parameter of relative effectiveness coefficient (REC) be used for the qualitative assessment of toothpastes containing active ingredients. REC is the ratio between the concentration of the active component in water eluates obtained after three minutes and adequately prolonged (up to the reaching of equilibrium state) dispersion of the toothpaste in distilled water at a 1:4 ratio (condition simulating the use of toothpaste in the oral cavity). The change in REC after storage following its production, as well as testing the toothpaste stability at high and low temperatures, provides an evidence for deviations in its quality. REC was applied for the assessment of toothpastes containing 0.5% zinc citrate as an active ingredient.


Assuntos
Cremes Dentais/normas , Óxido de Alumínio , Carbonato de Cálcio , Fosfatos de Cálcio , Ácido Cítrico , Controle de Qualidade , Dióxido de Silício , Zinco
4.
Artigo em Russo | MEDLINE | ID: mdl-8597213

RESUMO

The effects of physiotherapeutic factors such as electric sleep, sinusoidal modulated currents. UV radiation, interference currents, decimeter waves, laser radiation were studied in 600 sportsmen active in cyclic and acyclic sports. Recommended are both single and course procedures because the above factors are found to diminish immunodeficiency and to increase muscular performance in sportsmen.


Assuntos
Aptidão Física/fisiologia , Modalidades de Fisioterapia/instrumentação , Esportes/fisiologia , Adulto , Terapia Combinada , Eletrocardiografia , Eletromiografia , Homeostase/imunologia , Homeostase/fisiologia , Humanos , Masculino , Modalidades de Fisioterapia/métodos
5.
Artigo em Russo | MEDLINE | ID: mdl-8779181

RESUMO

The effects of balneological factors on cardiovascular system, external respiration, muscular performance, neuromuscular system and blood biochemistry give grounds to believe that inclusion of these factors in one-year training cycle extends the armery of effective tools recovering and improving muscular performance, preventing diseases and traumas in sportsmen.


Assuntos
Balneologia , Aptidão Física , Esportes , Banhos , Eletrocardiografia , Metabolismo Energético , Tolerância ao Exercício , Humanos , Respiração , Terebintina
6.
Int J Legal Med ; 105(3): 173-5, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1419879

RESUMO

When skulls and bones were exhumed from a mass grave in Bulgaria and subjected to medicolegal examination they were found to originate from 39 humans aged 36-60 years old who had been buried approximately 45-50 years ago. Solid structures which strongly resembled shrunken human brain tissue were found inside 2 intact skulls. Among other bones 5 similar structures were found one of which was an almost entirely preserved human brain, and the others were fragments from different regions of the human brain. Samples of these structures were immersed in 15% aqueous glycerol solution to soften and were examined by light and electron microscopy. Samples of this material and of fresh human brain were subjected to elementary atomic spectral analysis. These complex studies indicated the samples to be naturally mummified human brain tissue and that this process had occurred due to specific conditions within the cranial cavities after burial.


Assuntos
Encéfalo/patologia , Medicina Legal/métodos , Múmias/patologia , Adulto , Encéfalo/ultraestrutura , Bulgária , Feminino , Histocitoquímica , Humanos , Masculino , Microclima , Microscopia Eletrônica , Pessoa de Meia-Idade , Neurofibrilas/patologia , Neurofibrilas/ultraestrutura
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