Preservation of bacteria at the temperature of dry ice (-78.5 C) is a particularly valuable method for the maintenance of such organisms as Treponema pallidum which otherwise require continuous animal-to-animal passage. Turner (1938), Turner and Fleming (1939), and Turner and Brayton (1939) demonstrated that at the temperature of dry ice T. pallidum and relapsing fever spirochetes retain their ...

Permafrost thawing may lead to the release of carbon and nitrogen in high-latitude regions Northern Hemisphere, mainly form greenhouse gases. Our research aims reveal effects permafrost on CH4 N2O emissions from peatlands Xiaoxing’an Mountains, Northeast China. During four growing seasons (2011–2014), situ were monitored peatland under no-thawing, mild-thawing, severe-thawing conditions middle ...

Polyphenoloxidase (PPO), protease activities, melanosis and exudate loss of pre-cooked Pacific white shrimp (Litopenaeus vannamei) subjected to multiple freeze-thaw cycles (1, 3 and 5 cycles) using different thawing methods were studied. PPO and protease activities increased as freeze-thaw cycles increased (p < 0.05). Thawing using running tap water resulted in the higher increases in both PPO ...

OBJECTIVE The aim of the present study was to evaluate three thawing rates on the post thaw motility, viability and chromatin structure of buffalo semen frozen in 0.5-ml straws. MATERIALS AND METHODS In this experimental study semen was collected with artificial vagina (42℃) from four buffalo bulls.Split pooled ejaculates (n=4) were extended at 37℃ with a Bioxcell® extender. Semen was cooled ...

introduction: this study was performed to investigate the effect of vitrification procedure using ethyleneglycol as cryoprotectant on the follicular morphology of neonatal ovarian tissue of mouse after thawing andautotransplantation. material and methods: ovaries from 3 weeks neonate nmri mice were excised then vitrified in asolution of dmem medium containing ficol 70, sucrose, acetanied and et...

This experiment was designed to compare powdered egg yolk with fresh egg yolk in an extender for cryopreservation of Zebu bull semen. Sperm motility, plasma membrane integrity and viability were assessed at different stages of cryopreservation (post-dilution, pre-freezing and post-thawing). Sperm plasma membrane integrity remained similar at all the stages of cryopreservation. Sperm motility an...

A comparison between the physical, chemical, microbiological and technological properties of unpackaged pork Longissimus dorsi thawed at low ultrasound intensities and the properties of pork thawed by immersion in water (control) was carried out. Concurrently, the microbiological aspects of thawed meat were analysed. Ultrasound thawing was done at a constant frequency of 25 kHz and at low ultra...

Boar sperm TyrP32 is a 32-kDa tyrosine-phosphorylated protein that increases during the capacitation and acrosome reaction and during cryocapacitation. However, it is still unclear whether the increase in TyrP32 is an event that is limited to the process of sperm fertilization, including cryocapacitation. The aims of the present study were to demonstrate that TyrP32 is increased in dead spermat...