Contribution of the technique of thermostimulated currents for the elucidation of the nature of the Johari-Goldstein and other secondary relaxations in the vitreous state

2014 ◽  
Vol 21 (5) ◽  
pp. 2301-2309 ◽  
Author(s):  
Herminio P. Diogo ◽  
J. J. Moura Ramos
Keyword(s):  
Vitreous State ◽  
Secondary Relaxations ◽  
Thermostimulated Currents

Cryosectioning plant roots prepared by high-pressure freezing

1987 ◽  
Vol 45 ◽  
pp. 662-663
Author(s):  
R.E. Crang ◽  
M. Mueller ◽  
K. Zierold
Keyword(s):  
High Pressure ◽  
Cell Walls ◽  
Plant Tissues ◽  
Ice Crystal ◽  
High Pressure Freezing ◽  
Vitreous State ◽  
Radial Depth ◽  
Irregular Topography ◽  
Considerable Depth ◽  
Conventional Freezing

Obtaining frozen-hydrated sections of plant tissues for electron microscopy and microanalysis has been considered difficult, if not impossible, due primarily to the considerable depth of effective freezing in the tissues which would be required. The greatest depth of vitreous freezing is generally considered to be only 15-20 μm in animal specimens. Plant cells are often much larger in diameter and, if several cells are required to be intact, ice crystal damage can be expected to be so severe as to prevent successful cryoultramicrotomy. The very nature of cell walls, intercellular air spaces, irregular topography, and large vacuoles often make it impractical to use immersion, metal-mirror, or jet freezing techniques for botanical material.However, it has been proposed that high-pressure freezing (HPF) may offer an alternative to the more conventional freezing techniques, inasmuch as non-cryoprotected specimens may be frozen in a vitreous, or near-vitreous state, to a radial depth of at least 0.5 mm.

Modification of the Ornstein-Zernike equation as applied to the vitreous state

2006 ◽  
Vol 32 (2) ◽  
pp. 167-171
Author(s):  
A. S. Nesterov ◽  
D. S. Sanditov ◽  
Yu. V. Agrafonov ◽  
Sh. B. Tsydypov
Keyword(s):  
Vitreous State

Primary and secondary relaxations in bis-5-hydroxypentylphthalate

2005 ◽  
Vol 122 (8) ◽  
pp. 084511 ◽  
Author(s):  
S. Maślanka ◽  
M. Paluch ◽  
W. W. Sułkowski ◽  
C. M. Roland
Keyword(s):  
Secondary Relaxations

Primary and secondary relaxations in bis-5-hydroxypentylphthalate revisited

2005 ◽  
Vol 123 (20) ◽  
pp. 204507 ◽  
Author(s):  
K. L. Ngai ◽  
E. Kamińska ◽  
M. Sekuła ◽  
M. Paluch
Keyword(s):  
Secondary Relaxations

scholarly journals Tasa de preñez post vitrificación en los embriones de équidos producidos in vivo. Revisión

2020 ◽  
Vol 11 (4) ◽  
pp. 1142-1149
Author(s):  
Christian Urías-Castro ◽  
Ana Myriam Boeta
Keyword(s):  
The Other ◽  
Dramatic Reduction ◽  
High Permeability ◽  
Vitreous State ◽  
Preservation Method ◽  
Two Factors ◽  
Cryo Preservation ◽  
Transfer Index ◽  
Year 2000

Vitrification is a cryo-preservation method often used in embryos obtained from mares or jennies. It consists in the dramatic reduction of temperature to levels close to -196 °C, that allows the cryopreserving solution containing the embryo to pass from liquid to vitreous state. Several improvements to vitrification protocols have made possible to cryo-preserve embryos with different sizes; since during the first decade after the year 2000, only small embryos were successfully vitrified.  Embryos collected at the sixth day post ovulation (PO) are usually smaller or equal to 300 micrometers in diameter (≤ 300 µmØ) and can be  routinely vitrified following simple protocols; they have a higher post vitrification pregnancy rate (PVPR) when compared to large embryos which have more than 300 micrometers in diameter (˃ 300 µmØ).  The high PVPR of embryos ≤ 300 µmØ is due to an embryo capsule (EC) that is not fully developed yet and has a high permeability to cryo-preserving solutions. At present time, embryos collected either the seventh or eighth day PO are ˃ 300 µmØ and are characterized to have a low post vitrification survival; in order to increase their PVPR their EC might be punctured to make it permeable to cryopreserving solutions. Additionally, there are at least two factors that can be manipulated to increase the PVPR of embryos ˃ 300 µmØ; one is to reduce their size by aspiring their blastocoelic liquid (BL), and the other is to induce a high temperature transfer index (TTI) to rapidly reach -196 °C. 

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