• Title/Summary/Keyword: freezing, thawing

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A Study of Frost Penetration Depth and Frost Heaving in Railway Concrete Track (콘크리트 궤도의 동결깊이 및 동상량 측정 연구)

  • Lee, Daeyoung;Kim, Youngchin
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.1
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    • pp.35-41
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    • 2014
  • Many infra suructure such as road, railway, building and utility foundations have been damaged by the repeated freezing and thawing of the soil during winter and spring every year in seasonal frost region. The frost penetration depth is most important factor in the design of structure such as road, railway and building in seasonal frost region. This paper presents the results of calculation of frost penetration depth and frost heaving in concrete track for railway construction. Model concrete track were installed near the railway track in Gangwon, Gyeonggi, Choongbuk province and frost penetration depth were measured using methylene blue frost penetration depth gauge. Model concrete track in Cheolwon, frost heaving of concrete track were also evaluated. The measure of maximum frost penetration depth and frost heaving can be applied to design railway track for cold region in Korea.

Expression of Matrix Metalloproteinases (MMPs) and Their Tissue Inhibitors (TIMPs) in Frozen Sperm of Rabbit (동결융해 후 토끼 정자의 Matrix Metalloproteinases (MMPs)와 Their Tissue Inhibitors (TIMPs) 발현 양상)

  • Kim, Sang Hwan;Choi, Hwa Sik;Yoon, Jong Taek
    • Journal of Animal Reproduction and Biotechnology
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    • v.34 no.3
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    • pp.247-252
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    • 2019
  • We observed MMPs expression in all sperm groups, with pro-MMP showing lower expression than active MMPs. According to the results from each freezing extender, the sperm membrane integrity (HOST: Hypoosmotic Swelling Test) analysis in TCGGD (Tris 250 mM, Citric acid 88 mM, Glucose 47 mM, Glycerol 3%, Dimethylsulpoxide 3.5 M) is 59.8 ± 0.7, TCGSD (Tris 250 mM, Citric acid 88 mM, Glucose 47 mM, Sucrose 0.1 M, Dimethylsulpoxide 3.5 M) is 59.3 ± 0.5 were significantly higher (p < 0.05) among the experimental groups. And MMPs analysis result, we observed MMPs expression in all sperm groups, with pro-MMP showing lower expression than active MMPs. The expression of active MMP-2 was the highest in sperms frozen in TCGSD and TCGD (Tris 250 mM, Citric acid 88 mM, Glucose 47 mM, Dimethylsulpoxide 3.5 M), Meanwhile, sperms from the TCGGD and TCGED (Tris 250 mM, Citric acid 88 mM, Glucose 47 mM, Ethylene glycol 3%, Dimethylsulpoxide 3.5 M) group showed lower level of active MMP-2 expression. Together, these results indicate that adding glycerol or sucrose to the sperm freezing buffer would not only suppress MMPs expression but also minimize DNA fragmentation, providing a mean to improve the success rate in the in vitro manipulation of rabbit sperms. Therefore, these results suggest that TCGGD or TCGSD extender method for freezing-thawing of rabbit sperm increased the viability after thawing.

A Comparative Study on Fresh and Frozen Embryo Transfer after Superovulation in Black Bengal Goats(Capra-hircus)

  • Mishra, O.P.;Pandey, J.N.;Gawande, P.G.
    • Journal of Embryo Transfer
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    • v.17 no.2
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    • pp.91-100
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    • 2002
  • The experiment was divided into two phases. In phase-I fresh embryos were transferred and in Phase-II frozen embryos were transferred. Embryos were collected by using Dulbecco's phosphate buffered saline. In phase-I total of 65 ova were collected out of 107 ovulation in 18 goats. Recovery of ova was 60.74%, of which 51 (78.46%) was fertilized. Sixteen embryos were transferred to 10 recipient goats and kidding was observed in 6 goats, that produced 10 kids. Thus, 62.50% embryo survival and 60% kidding were achieved in phase-I. In phase-II of the experiment, 17 regular cyclic Black Bengal goats were used. The main purpose was to study the viability of caprine embryos after cryopreservation. In this phase the embryos were collected and frozen using Bio-cool freezers. A two step addition of cryoprotectants (5% glycerol and 10% glycerol) and three-step dilution of cryoprotectants with 1mole (M) sucrose was used. Embryos were preserved for 10 to 45 days. Out of 27 embryos preserved, 18 were recovered after freezing and thawing (37$^{\circ}C$ water bath) with 33.33% embryonic loss. Seventeen frozen and thawed embryos were transferred in 9 recipient goats, out of which kidding was observed in 6 goats and 7 kids were produced, giving a 66.66% kidding and embryo survival of 41.17%. The technique utilized for fresh and frozen embryo transfer can be successfully utilized to produce goats of superior genetic merits. The protocol used for addition of cryoprotectant, freezing, thawing and dilution was found suitable for caprine embryo freezing.

Cold Adaptation of Lactobacillus paraplantarum C7 Isolated from Kimchi

  • Kim, Su-Jung;Kim, Jong-Hwan;Park, Jae-Yong;Kim, Han-Taek;Jeong, Seon-Ju;Ha, Yeong-Lae;Yun, Han-Dae;Kim, Jeong-Hwan
    • Journal of Microbiology and Biotechnology
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    • v.14 no.5
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    • pp.1071-1074
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    • 2004
  • The effect of preadaptation at low temperature on cryoprotection was studied for Lactobacillus paraplantarum C7, a bacteriocin producer isolated from kimchi. L paraplantarum C7 cells in their log growth phase were incubated at $15^\circ{C}$, $10^\circ{C}$, or $5^\circ{C}$ for 2, 4, and 6 h, respectively, before being frozen at $-70^\circ{C}$. After 24 h of freezing, viable cells were counted after brief thawing. The freezing-thawing cycles were repeated three more times. Cells preadapted at $10^\circ{C}$ or $5^\circ{C}$ before freezing survived better than control cells, but preadaptation at $15^\circ{C}$ did not confer cryoprotection. Chloramphenicol addition did not destroy the cryoprotection, indicating that protein synthesis was not required for the development of cryoprotection. SDS-PAGE showed induction of a 6.5-kDa protein, a major cold-shock protein, in preadapted cells.

Practical Procedure of Sperm Cryopreservation of the Bar-tailed Flathead Platycephalus indicus (양태, Platycephalus indicus의 정자의 냉동보존)

  • Kim, Do-Hyung;Kong, Il-Keun;Rha, Sung-Ju;Yun, Ji-Won;Han, Kyeong-Ho;Kho, Kang-Hee
    • Korean Journal of Ichthyology
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    • v.23 no.1
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    • pp.75-79
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    • 2011
  • This study was conducted to investigate protocol standardization for cryopreservation spermatozoa of the bar-tailed flathead Platycephalus indicus. The suitability of the cryoprotectants, dimethyl sulphoxide (DMSO), glycerol and methanol were tested against three freezing rates and three thawing temperatures. DMSO and glycerol gave significantly higher motile index and survival rates than methanol. Among the freezing rates, freezing at a height of 2 cm above $LN_2$ surface for $10\;min^{-1}$ gave higher motile index and survival rates. In terms of best thawing temperature, $20^{\circ}C$ obtained the highest motility.

Effects of Butylated Hydroxytoluene on Freezability of Ram Spermatozoa

  • Farshad, A.;Khalili, B.;Jafaroghli, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.10
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    • pp.1276-1281
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    • 2010
  • The present study was conducted to investigate the effects of butylated hydroxytoluene (BHT) supplementation on diluted, cooled and frozen-thawed ram spermatozoa. After primary evaluation of collected ejaculates, only semen samples with motility of more than 70% and sperm concentration higher than $3{\times}10^3$ sperm/ml were used for cryopreservation. The selected semen samples were then pooled and diluted 1:4 with Tris Citrate Fructose Yolk (TCFY) extender supplemented with different concentrations of BHT (0.5, 10, 2.0 and 3.0 mM). As the control, semen was diluted and frozen in the diluent without BHT. Motility, progressive motility, viability, membranes and acrosome integrity were evaluated after dilution (part 1), cooling (part 2) and freezing and thawing (part 3). The results of the first part of the experiment showed that there were no significant difference between treatments in the motility, progressive motility, viability, membranes and acrosome integrity of spermatozoa, but the results with 2.0 mM BHT were slightly better than obtained with other levels of BHT and control extender. Significantly better results (p<0.05) were observed in the second part of the experiment for cooled spermatozoa characteristics, when extender was supplemented with 2.0 and 3.0 mM BHT. Furthermore, the results obtained in the third part of the experiment indicated that, after freezing and thawing, all evaluated semen characteristics were improved significantly (p<0.05) by increasing BHT levels, with the best results obtained for extender containing 2 mM BHT. Comparison of these results with those of control diluent, the effects of supplementation were significantly (p<0.01) better. However, the higher concentration of BHT (3.0 mM) reduced the motility, acrosomal integrity, viability and hypo-osmotic swelling response of spermatozoa compared to extender containing 2.0 mM BHT. In conclusion, the results obtained in this study showed that the semen quality of rams was improved when BHT was added to extender used before the freezing process.

Studies on Histological Changes in Marine Foods during Processing and Storage 2. Changes in muscular tissue of the eel, Anguilla japonica, by freezing storage (수산식품의 가공 및 저장중의 조직학적 변화에 관한 연구 2. 뱀장어 동결저장중의 조직변화)

  • SONG Dae-Jin;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.15 no.3
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    • pp.199-206
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    • 1982
  • Histological changes occurred by freezing storage and subsequent thawing, and changes of muscle fiber after heating and drying of the eel (Anguilla japonica) were observed under microscope . The results are as follows : (1) After one month of freezing storage the muscular tissue produced considerable number of extracellular and intracellular ice crystals. The sample stored at the temperature of $-40^{\circ}C$ produced ice crystals inside the muscle cells while sample stored at $-20^{\circ}C$, outside. (2) No changes were observed in the hypodermic fat after thawing regardless of storage temperature, while insufficient recovering of muscle cells were detected in the muscular tissue. Muscular tissues which have been stored $-20^{\circ}C$ showed severe change in shape due to dehydration. (3) Microscopic observation on muscle homogenate showed loss of transparency due to free-zing, disfiguration and contraction by drying and water seperation, and elasticity by heating.

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An Experimental Study on Evaluation Methods for Scaling Resistance of Cement Concrete Pavement (시멘트 콘크리트 포장의 스케일링 저항성 평가방법에 관한 실험적 연구)

  • Lee, Hyeon-Gi;Oh, Hong-Seob;Sim, Jong-Sung;Shim, Jae-Won
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.19 no.3
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    • pp.30-38
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    • 2015
  • In cold-climate regions, deicing agents is used for smooth traffic on the road due to freezing and snowdrift in winter. The use of de-icing salts has resulted in the accelerated scaling damage of concrete with salt damage under freezing and thawing condition. Scaling is the deterioration of concrete where in the paste-mortar structure delaminates in flakes from the surface of the concrete. Due to such damage, concrete pavement causes various problems such as early deterioration according to the decrease in the thickness of cover concrete and user's stability issues. Accordingly, various tests and evaluation methods have been suggested in order to evaluate these phenomena in other countries. However, there have been no regulations for the evaluation method in South Korea, and related studies are also very rare. Therefore, in this study, the evaluation methods proposed by each institution and country were investigated and the experiments were performed according to each regulation, followed by the comparison and analysis of the results. Furthermore, this study aims to suggest the optimized experimental method adopted to domestic field through the discussion of such experimental methods and results.

Green tea extract addition into a Tris-based egg yolk extender improves Bali bull sperm quality

  • Ragil Angga, Prastiya;Tri Wahyu, Suprayogi;Aldea Erian, Debora;Ani, Wijayanti;Anny, Amalia;Deny, Sulistyowati;Aras Prasetiyo, Nugroho
    • Animal Bioscience
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    • v.36 no.2
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    • pp.209-217
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    • 2023
  • Objective: The conservation of Bali bulls, the Indonesian native breed of cattle, is crucial for cattle breeding in Indonesia. To guarantee the spread of Bali bulls through artificial insemination the quality of the frozen semen must be high. To this end, adding an extender material to semen that increases spermatozoa's survival during cryopreservation is important. Green tea extract (GTE) can be used as cryoprotectant because its high antioxidant activity can help avoid reactive oxygen species formation. Methods: Semen of five Bali bulls from the National Artificial Insemination Center at Singosari, Indonesia was collected routinely twice a week. First, fresh semen inspection was performed to determine the feasibility of using Bali bulls as animal samples. The extender used in this study was Tris-based egg yolk. The samples were divided into four treatments: T0, no GTE added to the extender; T1, 0.05 mg GTE plus 100 mL extender; T2, 0.10 mg GTE plus 100 mL extender; and T3, 0.15 mg GTE plus 100 mL extender. The semen freezing process was conducted according to standard procedures and sperm quality parameters, i.e., sperm motility, viability, abnormalities, and membrane integrity observed pre-freezing and post-thawing. Results: There were significant differences in total motility, progressive motility, viability, and integrity membrane of Bali bull sperm at both pre-freezing and post-thawing after adding GTE into the extender. In contrast, there were no differences in abnormalities among treatments. Conclusion: Adding GTE at a 0.15 mg into 100 mL Tris-based egg yolk extender can improve the quality of cryopreserved Bali bull sperm.

Extraction Characteristics on Soaked Liquor of Omija (Schisandra chinensis) by Freeze-thawing Process (냉해동 처리에 따른 오미자 담금주의 추출 특성)

  • Lee, Eun Suk;Jee, Yun-jeong;Lee, Seung Eun;Kim, Hyung Don;Choi, Jehun;Kang, Min Hye;Kim, Geum Soog;Choi, Su Ji;Jang, Gwi Yeong
    • The Korean Journal of Food And Nutrition
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    • v.34 no.3
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    • pp.263-271
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    • 2021
  • Fresh Omija (Schisandra chinensis) has good marketability, but its quality is difficult to maintain during storage and distribution. Freezing and freeze-thawing treatments can be utilized for the quality maintenance and processing of cold press juice. In this study, the color, antioxidant properties, and the major components of soaked liquor from Omija with freeze-thawing treatment were analyzed during the extraction periods. Each of the frozen and freeze-thawed Omija samples was soaked in 35% ethanol, extracted for 15 days, and used for analysis. The frozen and freeze-thawed samples showed a tendency toward better color and higher antioxidant activity and major component levels than the controls, and freeze-thawing was the best. The results of this study showed that freeze-thawing treatment improved the color, antioxidant properties, and level of the major components of Omija soaked liquor, and freeze storage is suitable for making soaked liquor.