BACKGROUND: Freezing is a common way and one of the best methods of seafood preservation for long periods of time; however, the freeze thawing process may influence the quality of food. OBJECTIVES: Oxidation and denaturation of proteins, sublimation and recrystallization of ice crystals can cause changes in the quality of the frozen products. This study was aimed to evaluate the effect of three...

A series of experiments were conducted to determine the suitable freezing and thawing temperatures for the freezing of boar semen in 5 ml maxi-straws. The ultrastructure, in vitro fertilization (IVF) and artificial insemination (AI) of frozen-thawed semen were also be evaluated. The 5 cm freezing height gave the best results not only in post-thaw motility rate (54.00%), but also in normal acros...

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BACKGROUND The clinical efficacy of the current methods used for cryopreservation of metaphase II human oocytes is low. Meiotic spindle disorders are thought to be largely responsible for this situation. METHODS Supernumerary fresh metaphase II human oocytes were cryopreserved in 1,2-propanediol with 0.1 M sucrose using a slow freezing/rapid thawing programme. Meiotic spindles were analysed i...

introduction: to evaluate the quick cryopreservation technique on parameters of motility, morphology, and vitality of spermatozoa from normozoospermic ejaculates. materials and methods: in this prospective study, a total of 37 normal ejaculates were evaluated according to who criteria, then each sample was divided into two aliquets and sample was cryopreserved with quick freezing method. sperm ...

The surface displacement by seasonally freezing bulge and thawing subsidence are main hazards for engineering construction in permafrost regions, especially for the Qinghai-Tibet railway. For detecting the distortion at permafrost area, we try to study the interferometric method of monitoring the deformation at permafrost area with time-series EnviSat ASAR data. In this paper, the coherence cha...

The effects of different freezing and thawing rates on the post-thaw motility and membrane integrity of boar spermatozoa, processed as split samples in Maxi-straws or flat PET-plastic packages (FlatPack) were studied. A programmable freezing device was used to obtain freezing rates of either 20, 50 or 80 degrees C/min. Thawing of the samples was performed in a bath of circulating water; for 40s...

Germinating conidiospores of Neurospora crassa that were exposed to 45 degrees C, a temperature that induces a heat shock response, were protected from injury caused by freezing in liquid nitrogen and subsequent thawing at 0 degrees C. Whereas up to 90% of the control spores were killed by this freezing and slow thawing, a prior heat shock increased cell survival four- to fivefold. Survival was...

In this study, thermal conductivity of aloe was determined in the cooling process from 20°C to -11°C, and in the thawing process from -11°C to 20 °C using the tiny thermal probe method. The tiny thermal probe measurement system had the advantages of high accuracy, short test time, low temperature rise and little water removal and was found to give accurate and consistent experimental results. T...