• Journal of the Korea Concrete Institute
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• v.28 no.3
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• pp.309-316
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• 2016

In this study, performance of hardening accelerator types which promote setting and hardening of cement has been reviewed in order to develop early age strength of concrete with compressive strength of 21~27 MPa after examination of strength development of the concrete at early age according to curing temperature and unit cement(binder) content. As results, soluble mineral salt showed better hardening acceleration effect than organic salt in the scope of this study. Also, hydration reaction accelerating effect of $C_3S$ by Soluble mineral salt is effective on development of early age compressive strength and it was shown that the Pt's hydration reaction accelerating effect was the best. Construction duration reduction can be expected by securing compressive strength for prevention of early aged freezing damage in 25hour-curing time under curing temperature at $15^{\circ}C$. Also, it was shown that compressive strength of specimen cured at $5^{\circ}C$ was similar with plain specimen cured at $10^{\circ}C$. Therefore, it is expected that fuel costs and carbon dioxide can be reduced when the same construction duration is considered.

• 한국해양학회지
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• v.19 no.2
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• pp.217-227
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• 1984

Fish samples were collected by a trap net during 1981∼82 at the mouth of Cheonsu Bay to determine seasonal fluctuations in abundance and species composition. Examination of a series of trap net catches indicated that trap net data could be used, at least, for a qualitative analyses of a fish community and for a quantitative study of some pelagic fishes of Cheonsu Bay. Of the 64 species collected, a few temporal components predominated in abundance because of great seasonal fluctuations of water temperature. The early spring catch showed a low abundance value, and two cold weather seasonals, juvenile Enedrias fangi and Ammodytes personatus predominated in number and in weight. The number of species, abundance value in number and in biomass showed a peak in late spring when fishes move into bay for spawning and feeding after over-winterinig in the sea. Three pelagic species or warm weather seasonals, Harengula zunasi , Ammodytes personatus and Konosirus punctatus, predominated in abundance values. In this period night catch was significantly larger than day catch in terms of number of species, abundance in number and in weight Summer data showed a marked reduction of the number of species and abundance due to the loss of spawners probably by mortality or wide dipersion after spawning. A slight increase in abundance was observed in autumn by recruitment of the young-of-the-years. This catch was predominated by three juvenile fishes, H. zunasi, E. japonica and K. punctatus, which were the same species as in spring. The autumn catch showed no significant difference between day and night compositions.

• Korean Journal of Plant Tissue Culture
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• v.21 no.3
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• pp.161-166
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• 1994

Since garlics (Allium sativum L.) are propagated through cloves, infection by virus or other pathogens may become severe problem if not using high quality seed bulbs every year resulting in the reduction of yield and bulb quality, In order to solve this problem, the establishment of virus-free bulb production and its supply system have been required because no chemicals were found to eliminate viruses from seed bulbs. This experiment was conducted to develop an effective production technique of high quality seed bulbs using shoot-tip culture. Over 90% of shoot-tips explanted on January L 1990 were survived at constant temperature of either 20, 24 or 28$^{\circ}C$, wheres 88% at alternate temperature (28/20$^{\circ}C$). The growth of shoot and root was most vigorous at constant 24$^{\circ}C$, and least at alternate temperature (28/20$^{\circ}C$) condition. When shoot-tips were explanted June 21 to August 1,1991, survival and growth of shoot-tips was most vigorous on MS medium supplymented with 0.1 mg/L NAA and 2 mg/L kinetin and least 1 mg/L Gh$_3$. The shoot-tips taken from the seed bulbs stored at 4$^{\circ}C$ for 15 to 60 days were placed on MS medium, shoot growth and in vitro bulblet formation increased slightly as affected by the increase of told treatment period at 4$^{\circ}C$.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.71-80
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• 2005

Effects of low temperature ($8^{\circ}C$) on the hydraulic conductivity of young roots of a chilling-sensitive (cucumber; Cucumis sativus L.) and a chilling-resistant (figleaf gourd; Cucurbita ficifolia Bouche) crop have been measured at the levels of whole root systems (root hydraulic conductivity, $Lp_r$) and of individual cortical cells (cell hydraulic conductivity, Lp). In figleaf gourd, there was a reduction only in hydrostatic $Lp_r$ but not in osmotic $Lp_r$ suggesting that the activity of water channels was not much affected by low root temperature (LRT)treatment in this species. Changes in cell Lp in response to chilling and recovery were similar asroot level, although they were more intense at the root level. Roots of figleaf gourd recovered better from LRT treatment than those of cucumber. In figleaf gourd, recovery (both at the root and cell level) often resulted in Lp and $Lp_r$ values which were even bigger than the original, i.e. there was an overshoot in hydraulic conductivity. These effects were larger forosmotic (representing the cell-to-cell passage of water) than for hydrostatic $Lp_r$. After a short term (1 d) exposure to $8\;^{\circ}C$ followed by 1 d at $20\;^{\circ}C$, hydrostatic $Lp_r$ of cucumber nearly recovered and that of figleaf gourd still remained higher due to the overshoot. On the contrary, osmotic $Lp_r$ and cell Lp in both species remained high by a factor of 3 as compared to the control, possibly due to an increased activity of water channels. After pre-conditioning of roots at LRT, increased hydraulic conductivitywas completely inhibited by $HgCl_2$ at both the root and cell levels. Different from figleaf gourd, recovery from chilling was not complete in cucumber after longer exposure to LRT. It is concluded that at LRT, both changes in the activity of aquaporins and alterations of root anatomy determine the water uptake in both species. To better understand the aquaporin function in plants under various stress conditions, we examined the transgenic Arabidopsisand tobacco plants that constitutively overexpress ArabidopsisPIP1;4 or PIP2;5 under various abiotic stress conditions. No significant differences in growth rates were found between the transgenic and wild-type plants under favorable growth conditions. By contrast, overexpression of PIP1;4 or PIP2;5 had a negative effect on seed germination and seedling growth under drought stress, whereas it had a positive effect under cold stress and no effect under salt stress. Measurement of water transport by cell pressure probe revealed that these observed phenotypes under different stress conditions were closely correlated with the ability of water transport by each aquaporin in the transgenic plants. Together, our results demonstrate that PIP-type aquaporins play roles in seed germination, seedling growth, and stress response of Arabidopsis and tobacco plants under various stress conditions, and emphasize the importance of a single aquaporin-mediated water transport in these cellular processes.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.3
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• pp.554-561
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• 2009

Soyangin-Hyeongbangpaedok-san(SHBPDS) is a herbal formula used for the common cold or upper respiratory illness. In order to investigate the effect of SHBPDS, mice were orally administered with SHBPDS alcohol extract for 7 days followed by intravenous anti-CD3 injection. In addition, splenocytes and CD4 T cells were cultured with SHBPDS in response to anti-CD3 in vitro and cytokines and transcription factors were evaluated. In vivo treatment with SHBPDS significantly augmented the expressions of the percentage of CD4 T cells and CD 69, an indicator of early T cell activation. Serum levels of IL-4 were significantly increased but those of IFN-${\gamma}$ and IL-2 did not reach statistical significance. The expressions of IFN-${\gamma}$ and T-bet mRNA were significantly downregulated in SHBPDS treated mice while those of IL-4 and C-Maf were significantly upregulated. In vitro stimulation of splenocytes and CD4 T cells by SHBPDS resulted in a reduction in IFN-${\gamma}$ secretion and STAT4 activity. The IL-4 releases from both cells were slightly reduced, but STAT6 activity was rather increased. In conclusion, SHBPDS exerted an inhibition in the expression of IFN-${\gamma}$, T-bet and STAT4 while IL-4, C-Maf and STAT6 were increased. Further studies are required to examine its pharmacological effects using more appropriate animal experiments.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.220-228
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• 2017

Many crops including cereals, tuber crops, feeds, and turf grasses are often damaged by various environmental stresses such as drought, salt, cold, and high temperature, causing the reduction of their productivity. Plants are sessile and cannot escape from environmental stresses. Thus, plants evolve in the direction of overcoming the environmental stresses. Some plant genes such as ARF, ABI3, NAC, HSF, and WRKY are known to respond to environmental stresses as they transcriptionally regulate the stress response pathways. For example, the OsWRKY76 gene contributes to the enhanced resistance to low temperatures and pathogenic infections. The AtWRKY28 also plays a role in environmental stresses. Zoysiagrass (Zoysia japonica Steud.) is popularly grown for gardens and golf courses. However, the function of the WRKY gene, another environmental stress-related gene, is not known in zoysiagrass. In this study, the ZjWRKY3 and ZjWRKY7 genes with one shared WRKY domain have been isolated in zoysiagrass. The expression of these genes increased in response to low temperature, drought, and salt stresses. Furthermore, the infection of the brown patch-causing Rhozoctonia solani induced the expression of ZjWRKY3 and ZjWRKY7. The corresponding proteins bind to the W-box of the Zjchi promoter, possibly regulating their transcriptions. The researchers suggest that the ZjWRKY3 and ZjWRKY7 genes transcriptionally regulate abiotic and biotic stress related downstream genes.

• Journal of Chest Surgery
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• v.24 no.1
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• pp.54-63
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• 1991

Post-thoracotomy pain is so severe that lead to postoperative complications, such as sputum retention, segmental or lobar atelectasis, pneumonia, hypoxia, respiratory failure due to the patient`s inability to cough, deep breathing and movement. Many authors have been trying to reduce the post-thoracotomy pain, but there is no method of complete satisfaction. In 1974, Nelson and associates introduced the intercostal nerve block using the cryoprobe. The application of cold directly to the nerves causes localized destruction of the axons while preserving the endoneurium and connective tissue, thereby introducing a temporary pain block and able to complete regeneration of intercostal nerves. One hundred and two patients, who undergoing axillary or posterolateral thoracotomy at the Department of Thoracic and Cardiovascular Surgery in Korea University Medical Center between April 1990 and August 1990, were evaluated the effects of cryoanalgesia for the post-thoracotomy pain reduction. The patients were divided into two groups: Group A, control, the patients without the cryoanalgesia[No.=50], Group B, trial, the patients with cryoanalgesia[No.=52]. Before the thorax closed, in the group A, local anesthetics, 2% lidocaine 3cc, were injected to the intercostal nerves[one level with the thoracotomy, one cranial and caudal intercostal level and level of drainage tube insertion]. In the group B, cryoprobe was directly applied for 1 minute at the same level. Postoperative analgesic effects were evaluated by the scoring system which made arbitrary by author: The pain score 0 to 4, The limitation of motion score 0 to 3, The analgesics consumption score 0 to 3, The total score, the sum of above score, 0 to 10. For the evaluation of immediate analgesic effects, the score were evaluated at the operative day, the first postoperative day, the second postoperative day, and the seventh postoperative day. The effects of incision type, and rib cut to the post-thoracotomy pain were also evaluated. The results were as follows; 1. The intercostal block with cryoanalgesia reduced the immediate postoperative pain significantly compare with control group. 2. The intercostal block with cryoanalgesia improved the motion of the operation side significantly compare with control group. 3. The intercostal block with cryoanalgesia reduced the analgesics requirements at the immediate postoperative periods significantly. 4. The intercostal block with cryoanalgesia lowered the total score significantly compare with control group. 5. The intercostal block with cryoanalgesia were more effective to the mid-axillary incision than to the posterolateral incision 6. The intercostal block with cryoanalgesia were more effective to the patients without rib cut than to the patients with rib cut. 7. No specific complication need to be treated were not occurred during follow-up.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.930-936
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• 2004

Effects of rice cultivars and degree of milling (DM) on composition, pasting properties, total phenolic contents, and distribution of phenolic acids were investigated. Rice and bran fractions with 94.4, 92.0, and 90.4% milling yields from brown rice of four cultivars (Odae, Nampyung, Chucheong, and Ilmi) were used. Fat and ash contents of milled rices decreased with increasing DM, whereas protein contents were not affected. In rice bran, differences in fat and ash contents by cultivars were higher than those caused by DM. With increasing DM, gelatinization temperature of rice flour decreased, whereas peak viscosity and hold viscosity at $95^{\circ}C$ increased. While cold viscosity, final viscosity, and setback varied among cultivars, DM had little effect. Total polyphenolic contents in brown rice, milled rice, and rice bran were 93.9-88.8, 30.3-71.9, and 310.0-541.6 mg catechin eq/100g, respectively. Major phenolic compounds were identified as ferulic and p-coumaric acids. Total phenolic content of brown rice (65.9-27.9 mg%) decreased with increasing DM, whereas ratio of ferulic acid composition increased. Chucheong and Ilmi varieties showed biggest reduction of phenolic acid contents by milling. In rice bran, ferulic and p-coumaric acids were 157.8-240.2 and 31.8-90.4 mg%, respectively. Contents of sinapinic, benzoic, and m-hydroxybenzoic acids in rice bran were higher than those of brown and milled rices.

• Journal of the Korean Society of Food Culture
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• v.18 no.2
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• pp.139-150
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• 2003

The objective of this study consists in promoting seafood consumption by increasing its intake opportunities for children through analysis of seafood using frequency in the elementary school lunch program. For that purpose, randomly sampled out from elementary schools through the county were 155 dietitians and 5th grade 3581 children, on whom a mail survey was conducted to analyse their seafood using frequency, and preference, and lunch menu by seasons. Results of this study are as follows : The seafood using frequency of the respondents represented the highest value in one or two times a week, while obstacles in seafood use presented high values in the safety of food by 71.6% and children preference by 68.4%. The seafood intake frequency of the respondents showed the highest value in three or four times a week by 34.5% and the places of seafood intake indicated the highest response in the home by 43.5% and then school lunch and dining out. The dietitians responded that children for the most part had not a preference for seafood, whereas the children pointed out average by 46.2%. As for reasons for avoidance of seafood, the dietitians expressed the highest response in it depends cooking methods by 45.8%, while the children because of its peculiar taste and smell by 42.1%. Their required improvement showed the highest response in the taste improvement by 51.8%. The children most preference for seafood that dietitians thought included fried Alaska pollack and shrimp cutlet, while dislikes braised mackerels and seasoned cold jelly fish. Cooking methods frequently used were represented in order of soup, hot soup, and stew, and the children's preferred cooking method was from fried food. Above results suggested that the intention to increase seafood using frequency is needed to at the time of planning the menus so that more seafood-providing opportunities can be given. The development of cooking methods is urgently needed that can change the taste or the smell of seafood, and concurrently with this conveniences be taken into account in eating such as elimination of bones, etc. as early as the states of purchase or checking of seafood. The reflection of the preferred cooking methods is thought to contribute to the enhancement of satisfaction with the seafood as well as to the reduction of food remnants. The recommendation of intake of low preference but nutritionally good seafood is required to be expanded in nutrition education.

• Horticultural Science & Technology
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• v.30 no.4
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• pp.417-425
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• 2012

Salinity stress is one of the most serious factors limiting the productivity of agricultural crops. The aim of this study was to assess inter-cultivar (intraspecific) variation for salinity tolerance in six Korean rapeseed (Brassica napus L.) cultivars at the seedling stage. The effect of three different salinity stress levels (EC 4, 8, and 16 $dS{\cdot}m^{-1}$) on seedlings of six cultivars was investigated through leaf size, leaf dry weight, and leaf chlorosis. At the highest salinity level (16 $dS{\cdot}m^{-1}$), the mean decrease of leaf dry weight in 'Sunmang', 'Tammi', 'Tamla', 'Naehan', 'Youngsan', and 'Halla' was about 56.2, 56.9, 78.4, 79.3, 77.4, and 80.9%, respectively. 'Tammi' and 'Sunmang' showed much less reduction in leaf dry weight than all the other cultivars. In addition, diluted seawater treatments increased the occurrence of leaf chlorosis in six cultivars. At EC 8 and 16 $dS{\cdot}m^{-1}$, 'Naehan', 'Youngsan', and 'Halla' showed a higher level of leaf chlorosis than 'Tammi' 'Sunmang', and 'Tamla'. On the basis of these results, six cultivars were placed into salinity-tolerant and sensitive groups. 'Tammi' and 'Sunmang' were the salinity-tolerant cultivars, while 'Naehan', 'Halla', 'Youngsan', and 'Tamla' were the salinity-sensitive cultivars. 'Tammi' and 'Naehan' rated as the most tolerant and most sensitive cultivar, respectively. To further analyze protein expression profiles in 'Tammi' and 'Naehan', 2-D proteomic analysis was performed using the plants grown under diluted seawater treatments. We identified eight differentially displayed proteins that participate in photosynthesis, carbon assimilation, starch and sucrose metabolism, amino acid metabolism, cold and oxidative stress, and calcium signaling. The differential protein expressions in 'Tammi' and 'Naehan' are likely to correlate with the differential growth responses of both cultivars to salinity stress. These data suggest that 'Tammi' is better adapted to salinity stressed environments than 'Naehan'.