THE RELATION BETWEEN FROST RESISTANCE AND THE PHYSICAL STATE OF PROTOPLASM: I. THE PROTOPLASM AS A WHOLE

1940 ◽  
Vol 18c (11) ◽  
pp. 550-561 ◽  
Author(s):  
J. Levitt ◽  
D. Siminovitch
Keyword(s):  
Frost Resistance ◽  
Physical State ◽  
Injury Rate ◽  
Mechanical Injury ◽  
Brownian Movement

The protoplasm of hardy and non-hardy cells was compared with regard to displacement by centrifuging, rounding-up time on plasmolysis, deplasmolysis injury, rate of Brownian movement, resistance to and recovery from distortion by micromanipulation. The conclusions are: (i) When the cells are in the normally hydrated (i.e., turgid) condition there is either no difference in the consistency of hardy and non-hardy protoplasm, or else it is slightly less m the latter; (ii) when the cells are plasmolysed to the same degree (i.e., with a weaker plasmolyte in the case of the non-hardy) there is no difference in consistency; (iii) when the cells are in equilibrium with one and the same concentration of plasmolyte, the protoplasmal consistency of the non-hardy is greater than that of the hardy; (iv) the non-hardy are more susceptible to mechanical injury.

THE RELATION BETWEEN FROST RESISTANCE AND THE PHYSICAL STATE OF PROTOPLASM: II. THE PROTOPLASMIC SURFACE

1941 ◽  
Vol 19c (1) ◽  
pp. 9-20 ◽  
Author(s):  
D. Siminovitch ◽  
J. Levitt
Keyword(s):  
Refractive Index ◽  
Frost Resistance ◽  
Physical State ◽  
Surface Membrane ◽  
Protoplasmic Surface

Deplasmolysis injury, ductility of cytoplasmic strands, and the shape assumed by injected oil drops on deplasmolysis were investigated. The surface membrane of the protoplast of non-hardy cells stiffened when dehydrated osmotically. As a result, it ruptured readily when subjected to tension. The stiffening either failed to occur in hardy cells, or it arose only as a result of a much greater dehydration (depending on the degree of hardiness). The refractive index of the protoplasmic surface increased more on dehydration in the case of non-hardy than of hardy cells. Plasmolysis, if maintained for some time, induced a clumping of plastids and granules (systrophy) in non-hardy but not in hardy cells. All these facts indicate a greater hydrophily in hardy than in non-hardy cells—both of the surface membrane of the protoplasm and, as shown in Part I, of the protoplasm as a whole, although it is probably less marked in the latter.

Features of radiothermoluminescence of polypropylene and ethylene propylenediene elastomer SKEPT-4044 compositions with nanoscale metal-containing fillers

2020 ◽  
pp. 66-73
Author(s):  
A.M. Magerramov ◽  
◽  
N.I. Kurbanova ◽  
M.N. Bayramov ◽  
N.A. Alimirzoyeva ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Molecular Mobility ◽  
Fe3o4 Nanoparticles ◽  
Low Temperatures ◽  
Frost Resistance ◽  
Relaxation Processes ◽  
Ethylene Propylene ◽  
Temperature Range ◽  
Β Relaxation

Using radiothermoluminescence (RTL), the molecular mobility features in the temperature range of 77-300 K were studied for the polypropylene (PP)/ethylene propylene diene elastomer SKEPT-4044 with NiO, Cu2O and Fe3O4 nanoparticles (NPs) based on ABS-acrylonitrile butadiene or SCS-divinyl styrene matrices. It has been shown that the introduction of nanofillers in PP significantly affects the nature and temperature of γ- and β-relaxation processes, while the region of manifestation of the β-process noticeably shifts to the region of low temperatures. Composites with Cu2O NPs have a higher β-transition temperature Tβ than composites with other NPs. It was found that PP/SKEPT-4044 composites with Cu2O NPs with a dispersion of 11-15 nm and acrylonitrile butadiene thermoplastics have optimal frost resistance compared to other compositions.

Influence of Electro-Surface Properties of Mineral Filler on Frost Resistance of Powder Concretes

2019 ◽  
Vol 775 (10) ◽  
pp. 12-15
Author(s):  
Sh.M. RAKHIMBAEV ◽  
◽  
N.M. TOLYPINA ◽  
A.A. KOSINOVA ◽  
E.N. KHAKHALEVA ◽  
...  
Keyword(s):  
Surface Properties ◽  
Frost Resistance ◽  
Mineral Filler

Disseminated intravascular coagulation syndrome

2020 ◽  
pp. 22-40
Author(s):  
A. Kulikov
Keyword(s):  
Clinical Practice ◽  
Disseminated Intravascular Coagulation ◽  
Blood Cells ◽  
Physical State ◽  
Clinical Manifestations ◽  
Vascular Wall ◽  
Stages Of Development ◽  
Intravascular Coagulation ◽  
Hemostatic Disorder

Presented material reveals main links in the pathogenesis of hemostatic disorder. In particular, attention is paid to the role of the lungs, liver and other organs in the development of this process. Role of vascular wall and blood cells in regulation of the physical state of blood is described in detail. The most frequent factors leading to hypercoagulation are indicated. Difference between hypercoagulation and thrombophilia is shown. The latter is found in clinical practice quite often, but at the same time, it is poorly diagnosed. Such a terrible complication of hemostatic disorder as disseminated intravascular coagulation is described. Its classification, stages of development, clinical manifestations are offered to the readers.

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