• Parasites, Hosts and Diseases
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• v.25 no.2
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• pp.123-128
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• 1987

The author investigated the larvicidal action of liquid nitrogen against the metacercariae of Clonorchis sinensis, with an observation on the freshness and change of taste in the flesh of fishes. The results obtained were as follows: 1. The metacercariae in the mesh of Pseudorasbora parve, which were treated with liquid nitrogen ($-192^{\circ}C$), were not killed within 10 seconds, but completely killed over 30 seconds. In comparison, the metacercariae in the flesh of p. parka kept in a refrigerator ($-12^{\circ}C$) were killed only in 84% in 10-hour exposure group. 2. The freezing speed of fishes by liquid nitrogen was 4 min.(') and 15 seconds(") for Cyprinus carpio, 1'22" for Carassius carassius and only $30^{\circ}C$ for Pseudorasbora larva. 3. As for the freshness and taste of raw fresh water fishes, they were not deteriorated after the treatment with liquid nitrogen. 4. In animal infection experiment of C. sinensis metacercariae after freezing, they were found not infective after they were treated with liquid nitrogen. From the results, it is inferred that the treatment of fresh water fishes for longer than 30 seconds with liquid nitrogen is helpful to reduce the possibility of C, sinensis infection without alteration of the freshness and taste of fishes.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.546-549
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• 2002

The impact of storage conditions on the permeability of porcine buccal mucosa to [$^3H$]water and [$^{14}C$]mannitol was assessed. The fresh pocine buccal tissue (fresh tissue) was obtained by utilizing pig heads within 24 hours of slaughter. The stored and frozen porcine buccal tissues (stored tissue and frozen tissue) were obtained after the storage of the tissue intact in the pig heads at $4^{\circ}C$ or -$20^{\circ}C$, respectively, for 24 h. The results demonstrated that the barrier properties of the porcine buccal mucosa were maintained with regard to [$^3H$]water permeability when stored at $4^{\circ}C$ for 24 h. However, freezing the tissue resulted in tissue damage illustrated by a significant increase in [$^3$H]water permeability. [$^{14}C$]Mannitol does not appear to be a suitable model solute to assess the ex vivo permeability of porcine buccal mucosa due to its extremely low permeability.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.617-620
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• 2008

When fresh concrete is exposed to the cold weather, the concrete may happen frost damage because of freezing at early ages and the strength development may be go down. Therefore, this paper is intend to investigate the properties and availabilities of cold weather concrete using anti-freeze based formate-acetate for ensure of excellent concrete quality on cold temperature. According to test result for concrete in anti-freeze agent, strength properties in sub-zero temperature increases in comparison with concrete of non anti-freeze agent without decline of strength until later age. When anti-freezing agent is added by 3.0% to binder, it gives good effects on the performance of the fresh and harden concrete.

• KCI Concrete Journal
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• v.11 no.3
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• pp.29-43
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• 1999

The effects of superplasticizers on fresh and hardened concrete were investigated. The experimental program included tests on the workability and slump loss, bleeding, setting time, air content, compressive, tensile and flexural strength, permeability, shrinkage, freeze-thaw durability and creep deformation. Properties of superplasticized concrete were compared with those of conventional and base concretes. Superplasticizers were observed to have an appreciable fluidifying action in fresh concrete. They permitted a significant water reduction while maintaining the same workability. Bleeding of superplasticized concrete was much lower than that of conventional concrete of the same consistency. This indicates that the use of superplasticizers did not affect the tendency of segregation of fresh concrete. The compressive, tensile, and flexural strengths of superplasticized concrete were significantly higher than those of conventional concrete. The permeability and drying shrinkage and creep of superplasticized concrete were less than those of conventional concrete, but there were no significant differences between base and superplasticized concrete. Compared with base concrete, non-air-entrained superplasticized concrete had slightly higher freeze-thaw durability. and superplasticized concrete with an appropriate amount of entrained air Eave even better resistance to freezing and thawing.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.129-137
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• 2018

Objective: The objective of this research was to evaluate the physico-chemical, microbiological and sensorial qualities of restructured steaks processed from beef trimmings (grade I and II) and frozen beef (fresh beef as control and frozen beef). Methods: Beef trimmings from commercial butcher were collected, designated into 4 treatments differing in beef trimmings grade and freezing, processed into restructured steaks with 1% microbial transglutaminase and then analyzed for product quality. Results: The results showed that all meat from different groups could be tightly bound together via cross-linking of myosin heavy chain and actin as observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Microbial counts of psychrotrophic and mesophilic bacteria were not affected by treatments (p>0.05), and no detectable of thermophilic bacteria were found. Regarding effect of beef trimmings grade, steaks made from beef trimmings grade II (16.03% fat) showed some superior sensorial qualities including higher tenderness score (p<0.05) and tendency for higher scores of juiciness and overall acceptability (p<0.07) than those made from beef trimmings grade I (2.15% fat). Moreover, a hardness value from texture profile analysis was lower in steaks processed from beef trimmings grade II than those made from grade I (p<0.05). Although some inferior qualities in terms of cooking loss and discoloration after cooking were higher in steaks made from beef trimmings grade II than those made from beef trimmings grade I (p<0.05), these differences did not affect the sensory evaluation. Frozen beef improved the soft texture and resulted in effective meat binding as considered by higher cohesiveness and springiness of the raw restructured product as compared to fresh beef (p<0.05). Conclusion: The results indicated the most suitable raw beef for producing restructured steaks without detrimental effect on product quality was beef trimmings grade II containing up to 17% fat which positively affected the sensory quality and that frozen beef trimmings increased tenderness and meat binding of restructured beef steaks.

• Journal of Embryo Transfer
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• v.11 no.2
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• pp.137-144
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• 1996

The present study was carried out to obtain the pregnancy and delivery rate following transfer of fresh and frozen-thawed Korean native cattle(KNC) blastocysts(1~4 em-bryos / head) produced in vitro to Holstein recipients. The pregnancy rate of fresh and frozen-thawed KNC blastocysts produced in vitro was 50%(7 /14 heads) and 38.5%(5 /13 heads), respectively. The pregnancy rate of frozen-thawed KNC blastocysts produced in vitro frozen using 1.5M ethylene glycol and 1.4M glycerol for cryoprotectant was 33.3%(2 /6 heads) and 42.9 %(3 /7 heads), respectively. Seven calves including 2 sets of twin were born fiom 5 pregnant recipients receiving eleven fresh blastocysts. Three pregnant recipients were aborted among four pregnant recipients receiving twelve frozen-thawed blastocysts and one calf was born from the rest of one pregnant recipient.

• Food Science of Animal Resources
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• v.39 no.6
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• pp.1008-1014
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• 2019

This study investigated the effects of pressure-mediated protein changes on the ice nucleation temperature of pork loins. To variate chemical state of meat proteins, pork loin was pressurized at varying pressure levels (100-500 MPa) for 3 min, and moisture content, expressible moisture (EM) and differential scanning calorimetry (DSC) were analyzed. Although, all treatments showed similar moisture content, EM and degree of protein unfolding of pork loin showed different features as of 300 MPa. At moderate pressure treatments (100-200 MPa), all protein fractions were detected in DSC experiments, and pork loin had lower EM than control (p<0.05). Meanwhile, myosin and actin of pork loin treated at greater than 300 MPa were completely unfolded, and the treatments showed high EM compared to control (p<0.05). Unfolding of meat proteins was a factor suppressing ice nucleation, and the ice nucleation temperature tended to decrease with increasing applied pressure level. The ice nucleation characteristics of pressurized pork loin exhibited a potential application in freezing storage of pressurized meat with less tissue damage comparing to freeze fresh meat, and further exploration regarding the quality change after freezing of fresh and pressurized meat was warranted.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.4
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• pp.373-378
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• 2011

The freeze desalination cycle with seawater heat pump system is simulated and designed for the basic data for the design of freeze desalination system. The basic model of seawater heat pump system is refrigeration cycle and indirect freeze desalination method is used for seawater desalination. The cycle performance of seawater heat pump such as COP, compressor work, condensing capacity was analyzed and the desalination performance such as fresh water productivity and energy per unit fresh water productivity was compared with respect to the seawater temperature of condenser inlet and ice ratio in the evaporator. The compressor work and condensing capacity decreased with respect to the decrease of seawater inlet temperature. The energy per unit fresh water productivity in case of $8^{\circ}C$ seawater inlet temperature showed 28.9% lower than that of $20^{\circ}C$.

• Reproductive and Developmental Biology
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• v.29 no.3
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• pp.193-199
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• 2005

The cryopreservation of germ cells, sperm and embryos, has been largely used to increase the effect of artificial reproductive techniques for human infertility, but the efficiency of germ cell cryopreservation has been conkoversial till now. Thus, the effect of the cryopreservation of human sperm used for ICSI and the effect of the cryopreservation of embryos produced by ICSI on fertilizatiof development and pregnancy were investigated. Sperm freezing did not affect fertilizatiort development and pregnancy rates. Also, there was no significant difference between ejaculated and testicular sperm in ferclizatiort development and pregnancy. Embryo freezing methods, slow freezing and vitrificatior did not differ each other in viability and pregnncy rates. However, ICSI embryo freezing significantly decreased pregnancy rate compared to fresh embryos freezing (p<0.05). In conclusiof this result suggested that cryopreservation of sperm for ICSI did not affect on the resulted embryo development and pregnancy, but ICSI embryo cryopreservation would significantly inhibit pregnancy.

• Korean Journal of Animal Reproduction
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• v.20 no.1
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• pp.9-17
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• 1996

This study was conducted to investigate freezability of in vitro and in vitro matured rabbit oocytes, possibility of NT using frozen-thawed unfertilized oocytes, and NT efficiency by zona-slit micromanipulation. After freezing of in vitro matured oocytes, 33 to 49% of oocytes appeared normal morphology and 1.0M DMSO and 1.5M glycerol showed slightly high survival rate, but there was no difference in survival between two cryoprotectants. Freezability of in vitro matured oocytes was low in 1.5M glycerol and more sensitive to freezing. Efficiency of enucleation and fusion rate in method B was higher than that in method A and no difference in this efficiency was between 3 groups of oocytes in method B. Cleavage rate and developmental capacity to M＋B stage of fused embryos derived from frozen oocytes was greatly lower than that from fresh oocytes, respectively(39.1% : 79.5% ; 3.1% : 19.3%) and there was no difference in cleavage rate between DC voltages in two group oocytes. Additional incubation in cytochalasin B after electrical stimulation did not affect embryo development. In conclusion, it is suggested that enucleation and nucelar transfer by slitting of zona is more effective method in rabbit and that further study on optimum freezing conditions for in vitro matured oocytes is necessary to use as recipient oocytes.