The aim of the present study was to evaluate the protective effect of L-glutamine (L-Gln) against cryopreservation injuries on boar sperm. In Experiment 1, L-Gln from 20 to 80 mM was evaluated as a supplement for a standard freezing extender (egg yolk - EY - 20%, and glycerol 3%). No significant improvement (P>0.05) was obtained for any post-thaw sperm parameter assessed (objective sperm motili...

Wood frogs (Rana sylvatica) exhibit marked geographic variation in freeze tolerance, with subarctic populations tolerating experimental freezing to temperatures at least 10-13 degrees Celsius below the lethal limits for conspecifics from more temperate locales. We determined how seasonal responses enhance the cryoprotectant system in these northern frogs, and also investigated their physiologic...

To evaluate the effects of industrial by-products materials on the performance of porous concrete for plant growth, this study investigated the physical, strength, and freeze/thaw resistances of porous concrete for plant growth, prepared by replacing cement with blast furnace slag powder at 60% by weight, and replacing natural stone aggregates with coarse blast furnace slag aggregates at rates ...

The effects of storage temperatures, repeated freeze-thaw cycles, or delays in separating plasma or serum from blood samples are largely unknown for heat shock protein 27 (HSP27). We evaluated (1) the imprecision of the HSP27 assay used in this study; (2) the in vitro stability of HSP27 in blood samples stored at 4°C for up to 6 hr with immediate and delayed serum/plasma separation from cells; ...

The effect of bacterial cellulose (BC) on the freeze-thaw stability of rice starch gels during 5 freeze-thaw cycles were investigated, using scanning electron microscopy (SEM), rapid visco analyzer (RVA), X-ray diffractometry (XRD), differential scanning calorimetry (DSC) and textural analyzer (TA). SEM micrographs of freeze-thaw gels showed that smaller pore size and a thicker surrounding matr...

Membrane water content is of vital importance to the freezing durability proton exchange membrane fuel cells (PEMFCs). Excessive could cause irreversible degradation cell components and deteriorate performance lifetime. However, there are few studies on critical content, a threshold beyond which damage occurs, for cold storage PEMFCs. In this work, we first proposed method measuring using resis...

Winter soil respiration (Rs) is becoming a significant component of annual carbon budgets with more warming in winter than summer. However, little is known about the controlling mechanisms of winter Rs in dryland. We made continuous measurements of Rs in four microsites (non-crust (BS), lichen (LC), moss (MC), and a mixture of moss and lichen (ML)) in a desert shrub-land ecosystem northern Chin...

BACKGROUND We designed this study to detect the cryoinjury rate on human sperm after serial freezing and thawing, taking into consideration the effects of using cryovials and straws. MATERIALS AND METHODS In this experimental study, semen specimens obtained from 15 subjects were divided into normozoospermic and oligozoospermic groups. Each of the normozoospermic and oligozoo spermic semen spe...

In the seasonally frozen soil regions of northern China, silty clay is widely used as a subgrade bed filler in heavy-haul railway construction. this paper, influence freeze-thaw cycles on dynamic strength properties (strength parameters and critical stress) fillers before after cement improvement was investigated by series triaxial tests under different confining pressure conditions, test resul...

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 ...