• Title/Summary/Keyword: freezing days

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A study on freeze-thaw evaluation criteria for road tunnels considering climate characteristics (국내 기후특성을 고려한 도로터널의 동결-융해 평가기준 연구)

  • Moon, Joon-Shik;An, Jai-Wook;Kim, Hong-Kyoon;Lee, Jong-Gun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.1
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    • pp.121-133
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    • 2020
  • Globally, the frequency and intensity of abnormal climate events are increasing. Since this can directly damage lives and property, it is important to establish and implement an appropriate maintenance strategy in response to abnormal weather. Facilities built in cold regions where cold wave or heavy snow occurs frequently can be more damaged by freeze-thaw than facilities located in other regions. However, there are no clear criteria for quantitatively identifying the damage of freeze-thaw and how to cope with it. Therefore, based on the results of indoor freezing tests, the freezing conditions considering regional climate characteristics were selected as one day at -14℃, two days at -7℃ or three days at -5℃. As a result, it was confirmed that they were in the freeze-thaw environment in order of Daegwallyeing (8.3 times), Cheorwon (5.3 times) and Taebeak (4.9 times) in Gangwon region. Through this study, the evaluation criteria of freeze-thaw of road tunnels were newly proposed. The freeze-thaw evaluation criteria of the road tunnel presented in this study can be used for the quantitative evaluation and maintenance strategy of tunnels in cold regions.

Investigation on Techniques for Evaluating Hardiness to Low Temperature in Cereals (화곡류의 내한성 검정기술에 관한 연구)

  • Chae-Yun Cho;J. D. Hayes
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.14
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    • pp.97-109
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    • 1973
  • 1. The relatively lower prehardening temperature was more effective on increase of the hardiness of the intermediately hardy varieties than the higher one but either the extremely hardy or nonhardy varieties did not respond to the temperature as much as the intermediate types. 2. Five degree Centigrade was generally more favorable than $2^{\circ}C$ on hardening of the plants, especially when frozen at higher temperature for shorter duration. 3. It appears that photoperiod during prehardening and hardening did not play so important role as temperature on the hardiness. 4. The higher the soil moisture content, the higher the frost injury occurred. 5. Application of nitrogen increased markedly the hardiness and % DM of the plants. Percentage of dry matter of young seedlings might be used as an easy and rough criterion for evaluating hardiness since there was a highly significant regression of varietal frost injury on the %DM. 6. Four days appeared to be enough for hardening of plants although the plants increased gradually the hardiness as duration of hardening extended. Dehardening of the plants at relativity higher temperature took place rapidly within one to four days. 7. Under this controlled environment, freezing at about $-8^{\circ}C$ for 24 hours seemed the best for the purpose of evaluating the hardiness to low temperature. 8. It is believed that assessment of frost injury should be done at least one week after freezing. Some varieties showed strong ability to recover from the damage as recovery period was extended. 9. As a whole, Cd 80 and 83 were the most hardy and followed by Cappelle and Maris Otter. Four. winter oats varieties and Jufy I belonged to the intermediate type while the other three spring varieties were nonhardy at all. Peniarth was comparable with Maris Otter in hardiness. S 147 appeared the least hardy among the winter oats varieties. 10. It is evident that water-soluble carbohydrate content is associated with the hardiness to some extent but not primary factor involved in hardiness.

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Changes in the Microflora of Marine Fishes during Storage by Partial Freezing (해산어(海産魚)의 부분동결(部分凍結)에 의한 Microflora의 변화(變化))

  • Park, Chan-Sung;Choi, Kyoung-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.15 no.1
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    • pp.56-62
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    • 1986
  • Marine fishes, sardine(Sardinops melanosticta), scad kingfish(Caranx equula), horse mackerel(Trachurus japonicus) and file fish(Navodon modestus), were stored for fifty days with partial freezing at$-3.5^{\circ}C$. During the storage, the changes in microflora and volatile nitrogen content was investigated. The fishes exhibited $10^4\;to\;10^6$ of bacterial cells per square centimeter of their skin just before they were submitted to the storage. The bacterial cell number was increased as $10^6\;to\;10^8$ cells as the storage time passed over twenty-two days. Offensive odor which is typical in the spoilage of fishes became strong as increase the bacterial cell numbe. The major isolates among the three hundred strains of bacteria isolated from the fish skins were identified as Pseudomonas I/II, III/IV-H, Vibrio and Moraxella. The same was found in the spoiled fishes, however, Pseudomonas I/II, was predominant on contrast to that of fresh fishes. Pseudomonas III/IV-NH, Flavobacterium, Cytophaga and Micrococcus were also found in early period of storage, but they disappeared as the progress of storage. Nine per cent of isolates were unidentified.

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Anti-stress Effect of Pyroligneous Liquid in SD Rats and ICR Mice

  • Kim, Mi Kang;Yu, Gu Yong;Tan-Lee, Blendyl Saguan;Oh, Hyun Jin;Dong, Kyung Woo;Jeong, Seung Hwa;Han, Seong Wook;Cheong, Jae Hoon
    • Biomolecules & Therapeutics
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    • v.11 no.4
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    • pp.249-256
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    • 2003
  • Pyroligneous liquid(PL) is produced by carbonizing Oak in 350-40$0^{\circ}C$. It is traditionally used for treating stress-related disorder, hepatic disease, immune disorder, G-I disorder and inflammatory disease. The aim of this study is to investigate anti-stress effects of PL. The experiments were performed with the use of young(9 weeks of age) male rats of SD strain and the male ICR mice (20-25 g). Animals of the normal group were not exposed to any stress and the control group were exposed to stress. The rats of the Ginseng, diazepam(BZ) and PL supplementary group were orally administered once a day 100 g of Ginseng extract-kg body weight, 5 mg of BZ/kg body weight and 1 ml of PL100 g body weight and then exposed to stress. The mice of the Ginseng, BZ and PL supplementary group were given water containing 100 g of Ginseng extract/100 ml potable water, 5 mg of BZ/kg 100 ml of drinking water and 10 ml of PL/100 ml of drinking water and exposed to stress. Animals were given materials for 7 days after stabilizing them, and then were given supplementary materials for 5 days with stress. They were stressed by immobilization for 30 minutes and then the animals were exposed to electroshocks for 5 minutes. We recorded stress-related behavioral changes of experimental animals by stressing them using the Etho-vision system and measured the levels of corticosterone in blood While stress suppressed locomotor activity of animals, PL-supplementation partially blocked the stress effect of locomotion in rats and mice, and also partially blocked stress-induced behavioral changes such as freezing, burrowing, smelling and rearing activity in rats and freezing, grooming, tailing and rearing in mice. The staying time of stressed rats and mice in open area decreased and in closed area it increased relatively in elevated plus maze test. However, these changes also partially were blocked by PL-supplementation. PL-supplementation decreased levels of blood corticosterone increased by stress in rats. These results suggest that PL protects partially the living organism from stress attack in some cases.

Improvement of Reproductive Efficiency of Artificial Insemination Following Estrus Induction in Dog II. Semen Freezing and Artificial Insemination in Dog

  • Lee, Y. R.;S. Y. Choe
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.92-92
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    • 2002
  • Considerable attention has been focused on the cryopreservation of semen and estrus induction in dog, as consequence of poor productivity caused by long anestrus period, in order to enhance the productivity of youngs and to preserve the breeds. The objectives of this study were to evaluate semen quality after cryopreservation and to evaluate the Pregnancy rate after insemination (AI). Fifty infertilie dogs (age 2∼3 years) were selected for the study and divided into three different estrus induction treatment groups. Group 1: dogs (n=15) were given clomifene (0.1 mg/kg) orally for five days at 12 hr intervals. Group 2: dogs (n=15) were given bromocriptine (50 $\mu\textrm{g}$/kg) orally for five days at 12 hr intervals, followed by single injection intravenously of 500 IU GnRH (Group 3, n=20) when pro-estrus occurred. The rates of pregnancy in estrus inducted dogs mated naturally compared to those inseminated artificially with ejaculated fresh semen and frozen-thawed semen. Estrus detection was performed using the method of vaginal smear and confirmed by the plasma progesterone assay. The ejaculated semen to freeze was exposed to a mixture of Tris extender with cryoprotectant (Trisma, 81 mM: TES, 209 mM: citric acid, 6 mM; glucose, 5 mM; glycerol, 8%) and cryopreserved gradually by slow-cooling at 17 cm above the surface of liquid nitrogen (LN$_2$) for 23 min. The motility of frozen-thawed spermatozoa was assessed by phase-contrast microscopy. To assess their viability and acrosome content, spermatozoa were stained with a vital stain and Fluorescence conjugated lectin Pisum Savitum Agglutinin (FITC/PAS), respectively. Pregnancy was confirmed by ultrasonograpy on day 25, 35 and 55 post insemination. The use of fresh semen, the pregnancy rates were observed 66.6, 66.6, 75.0 and 83.3% in natural estrus, clomifene induced, bromocriptine induced and a combination of GnRH and bromocriptine, respectively. The use of frozen-thawed semen, the pregnancy rates were observed 66.6, 33.3, 50.0 and 60.0% in natural estrus, clomifene induced, bromocriptine induced and a combination of GnRH and bromocriptine, respectively. No difference was observed in the number of offspring produced among natural estrus and treated groups inseminated with fresh or frozen-thawed semen. In conclusion, the pregnancy rate of dogs treated with a combination of GnRH and bromocriptine was more effective than use of clomifene or bromocriptine only. In addition, frozen-thawed semen can be used successfully far artificial insemination in dog.

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The Research on the Numbers of Workable Days for Earth Works in Different Regions in Korea (Part II) (한국의 지역별 토공가능일수에 관한 조사연구)

  • 안병기;민병섭;박승범
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.13 no.3
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    • pp.2372-2387
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    • 1971
  • 1. Being seen at the table (20), the number of days which monthy average air temperatures are three degrees of Celsius thermometer($3^{\circ}C$) or more, is the highest marks to be 365 days at Cheju, secondly, 334 days at Pusan, and, Ulsan, Pohang, Mokpo,Yosu and Ullung-Do which all are coastal region are all 306 days, besides, all north area of Taegu and Kwang ju have 275 days consquently, there are 90 days, differance between maximum and minimum. 2. Being seen at the table(22), freezing dates to be influenced upon earth works are obtained, if (1) item is subtracted from 365 days one year. 3. Being seen at the table(18), number of rainy days of which records are 1 millimeter and over to be influenced upon earth through works, days which monthly average air temperatures are $3^{\circ}$ or more, is the maximum to be 100 days at Cheju and its minimum is 60 days at Taegu. Every other region show 70 days or so. But Ullung-Do is 90 days. 4. Being seen at the table (26), the numbers of annual earth works possibility days(4) are obtained, if the values (3) which number of rainy days more than 1 millimeter during the same period are multiplied by 1.27(coefficient of hindrance to earth works) are subtracted from the number of days which monthly average air temperatures $3^{\circ}$ or more [(1)-(3)=(4)]. 5. The number of annual earth works possibility days by regional groups is the maximum to be 242 days at Pusan, and Cheju are 239 days. Other regions are from 218 days to 181 days, namely, they are about 200 days.

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Optimization of In Vivo Embryo Production and Pregnancy following Embryo Transfer in Hanwoo Cattle

  • Jeon, Soon-Hong;Jung, Kyoung Sub;Choi, Jae-Won;Heo, Young-Tae;Xu, Yong-Nan;Kim, Nam-Hyung
    • Journal of Embryo Transfer
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    • v.28 no.4
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    • pp.307-314
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    • 2013
  • Embryos formed in vivo were collected from 171 donors housed in Chung Cheong Buk-Do Institute of Livestock and Veterinary Research of the Chungbuk community during the years 2009~2012. We evaluated annual embryo collection, effect of follicle stimulating hormone (FSH), controlled internal drug release (CIDR) and prostaglandin (PG) administration to the donor for superovulation and controlling the estrus cycle, seasonal effects of embryo collection and compared the number of embryos recovered as per the collection days and pregnancy rate. In all, 1,243 embryos were collected from 118 donors with an average of $7.31{\pm}5.35$ embryos per donor, out of which 69.4% were transferable. Dosages of FSH required for inducing superovulation in various donors were compared. Average number of embryos collected from donors administered with 30 AU of FSH ($7.13{\pm}5.74$ per donor) was not significantly different from that of donors who were given an injection of 24 AU of FSH ($7.53{\pm}4.91$ per donor). However, the percentage of transferable embryos in the 30AU FSH-administered group (63.2 %, 449 of 711) was higher than that in the 24AU FSH-administered group (77.8%, 414 of 532). In the group of donors under a natural estrus cycle, the FSH dose administered did not influence the number of transferable embryos produced ($7.49{\pm}6.25$ per donor for 30 AU of FSH vs $7.49{\pm}4.92$ per donor for 24 AU of FSH). However, in donors administered with CIDR and PG for controlling the estrus cycle, the FSH dose affected the average number of transferable embryos collected ($4.25{\pm}2.87$ per donor for 30 AU of FSH vs $8.50{\pm}6.36$ per donor for 24 AU of FSH). We collected embryos from donors 6, 7 or 8 days after artificial insemination (AI). Results showed that the percentage of transferable embryos among those collected 8 days after AI was significantly higher than that among embryos collected 6 or 7 days after AI. Seasonal variations did not affect number of recovered embryos and pregnancy rates in natural estrus cycle and CIDR treatment groups (48.28% and 42.55%) but higher than pregnancy rate of frozen embryos (19.63%). These results indicated that administration of FSH beyond a threshold dose (at least 24 AU) has no beneficial effect on the production embryos and that collection of embryos 7~8 days after AI is optimal for embryo recovery. CIDR treatment induced superovulation in short term and had no influence on the natural estrus cycle. Finally, although good-quality embryos were transferred, freezing significantly reduced the pregnancy rates after transfer.

The impact of freeze-drying on the glycoproteomic profiles of human milk

  • Hahn, Won-Ho;Bae, Seong-Phil;Lee, Hookeun;Park, Jong-Moon;Park, Suyeon;Lee, Joohyun;Kang, Nam Mi
    • Analytical Science and Technology
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    • v.33 no.4
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    • pp.177-185
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    • 2020
  • Human milk (HM) glycoproteins play important roles protecting infants against various pathogens. Recently, freezing HM is reported to affect some glycoproteins and freeze-drying is suggested as an alternative method. However, the effects of freeze-drying on HM glycoproteins were not evaluated yet. Six fresh HM samples were collected from three healthy mothers at 15 and 60th days of lactation from each mother. Each sample was divided into frozen and freeze-dried subgroups yielding totally 12 samples, and the glycoproteomic analysis was performed by liquid chromatography mass spectrometry. The results were compared between samples of 15 and 60th days of lactation, and before and after the freeze-drying. Totally, 203 glycoproteins were detected. The glycoprotein levels were not different between two groups of 15/60th day of lactation and before/after freeze-drying groups (P > 0.050). In addition, significant correlation of glycoprotein levels was found between the different lactation stages (r = 0.897, P < 0.001) and the status of freeze-drying (r = 0.887, P < 0.001) in a partial correlation analysis. As no significant change of HM glycoproteins was not found after the freeze-drying, we hope that introducing freeze-drying to HM banks is supported by the present study. This work was supported by the National Research Foundation (NRF) of Korea grant funded by the Korea government (MSIP) (No.2017R1D1A1B03034270; No.2020R1A2C1005082).

Stress Related Activities of Gardenia Jasminoides: Comparative Study with the Effects of Red Ginseng (치자의 스트레스 관련 생리 활성: 홍삼과의 비교 연구)

  • Ko Hong Sook;Lee Geum Seon;Tan-Lee Blendyl Saguan;Park Hyung Geun;Yoo Gu Young;Yim Dong Sool;Jung In Kyung;Oh Sei Kwan;Cheong Jae Hoon
    • YAKHAK HOEJI
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    • v.49 no.4
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    • pp.291-298
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    • 2005
  • Gardenia Jasminoides(GJ) is traditionally used for treatment of hepatic disease, insomnia, anxiety, and inflammatory disease. The aim of this study is to examine effects of GJ extract in response to stress. Animals of the normal group were not exposed to any stress and the control group were exposed to stress. The rats of the Ginseng and GJ supplementary group were orally administered once a day with 100mg of red ginseng extract, 100mg of GJ extract/kg body weight. The mice were given water containing 200mg of red ginseng extract, 200mg of GJ extract/100ml potable water. Animals were given supplements for 7 days without stress, and then were given supplements for 5 days with restraint and electroshock stress. After loading final stress, we examined stress related behavioral changes of experimental animals and measured the levels of blood corticosterone. GJ-supplementation partially blocked the stress effect on locomotion and elevated plus maze test in rats, and also partially blocked stress-induced behavioral changes such as freezing, burrowing, face-washing, smelling and rearing behavior in rats. The effect was almost equipotent to Ginseng's effect. GJ-supplementation didn't influence on fatigue related behavior or physical stress resistance. GJ-supplementation decreased the levels of blood corticosterone which is increased by stress in rats. These results suggest that GJ protects partially the living organism from stress attack and it has the potential to be used as a functional material to alleviate stress response.

Quality Improvement of Frozen and Chilled Beef biceps femoris with the Application of Salt-bicarbonate Solution

  • Sultana, A.;Nakanishi, A.;Roy, B.C.;Mizunoya, W.;Tatsumi, R.;Ito, T.;Tabata, S.;Rashid, H.;Katayama, S.;Ikeuchi, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.6
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    • pp.903-911
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    • 2008
  • The effects of salt and bicarbonate solution on overall meat quality in beef biceps femoris muscle were investigated with the application of chilling and freezing conditions. Muscles were injected to a target of 120% of original meat weight with a solution containing 1.2 M sodium chloride, 0.25 M sodium bicarbonate and 0.1% ascorbic acid (pH 7.2). Half of the meat samples, considered as chill treatment and chill control, were stored at $4^{\circ}C$ up to five days; while the other half, frozen treatment and frozen control, were kept in a freezer at $-20^{\circ}C$ for seven days. Compared with untreated control, treated meats had higher water holding capacity (p<0.05), lower drip loss (p<0.05) and lower shear force (p<0.07) with higher overall acceptability (p<0.05) in sensory evaluation. Morphological observations demonstrated smooth and gummy meat surface due to the solubilization of myofibrillar proteins and the distortion of connective tissue in treated raw meats; and in the case of cooked meat, treatment caused the fragmentation of myofibrils, which might be responsible for a lower shear value in salt-bicarbonate treated beef biceps femoris muscle.