• Title/Summary/Keyword: water control

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Effects of Pretreatments of Surfactants, Germicides, Sucrose, or Hormones on the Vase Life of Cut Rose 'Red Sandra' (계면활성제, 살균제, 자당 및 호르몬 전처리가 절화장미(cv. Red Sandra) 수명에 미치는 영향)

  • Son, Ki-Cheol;Kim, Tae-Sik;Byoun, Hye-Jin;Chang, Myoung-Kap
    • Horticultural Science & Technology
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    • v.16 no.4
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    • pp.533-536
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    • 1998
  • In order to develop a pretreatment solution for cut rose, the effects of surfactants [Tween 20, Triton X-100, polyoxyethylene 4 lauryl ether (PLE)], germicides (aluminum sulfate, $AgNO_3$, dichloroisocyanuric acid, STS, benzalkonium chloride, 8-hydroxyquinoline sulfate), sucrose, and hormones (ABA and kinetin) on the longevity and quality of 'Red Sandra' were investigated in environment-controlled room. Although 20 and 50 ppm Tween 20, and 500 ppm PLE appeared, in appearance, to be effective in retarding blueing and wilting, respectively, they didn't show statistical differences as compared to distilled water control. Among germicides, $AgNO_3$ was the most effective in delaying petal blueing, petal withering, and reduction of fresh weight, regardless of its concentration, while, in the case of STS, only 1mM treatment was effective in delaying of petal withering. Only 5% sucrose treatment delayed petal blueing, petal withering, and bent neck, but showed no significant difference as compared to 500 ppm aluminum sulfate. Finally, single or combination treatments of ABA and cytokinin were found to rather stimulate the senescence of cut rose.

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Studies on Early Detection of the Chemical Hepatocarcinogenesis in Newborn Rats (신생랫드를 이용한 화학적 간암발생의 조기진단에 관한 연구)

  • 장민열;김형진;이영순
    • Journal of Food Hygiene and Safety
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    • v.6 no.1
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    • pp.13-26
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    • 1991
  • This study was performed for searching for non-hepatectomy medium-term bioassay model by using newborn female rats. Newborn female Sprague-Dawley rats (1 day old) were given an intraperitoneal injection of 150 mg/kg of diethylnitrosamine (DENA). After three weeks, all rats were weaned and divided into three groups. Group 1 were fed on diets containing 0.01% 2-acetylaminofluorene (2-AAF) as a promoter for three weeks. Group 2 were given 0.05% phenobarbital (PB) in drinking water as a promoter for 8 weeks. Group 3 was control group. The autopsy was carried out at 4 weeks and 8 weeks after weaning. Preneoplastic lesions were indentified with immunohistochemical staining for glutathione S-transferase placental form (GST-P). In liver weight to body weight ratios, group 2 showed significant difference from group 1 (p<0.001) at 4 weeks after weaning. Group 1 and group 2 showed significant difference from group 3 at 8 weeks after weaning (p<0.0I, p<0.001), respectively. In quantitative analysis for GST-P positive lesion area by using Image Analyzer, group 1 and group 2 represented significant difference in comparison with group 3 at early 4 weeks after weaning (p

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A Survey on the Sanitary Management in Food Service Institutions (집단급식소의 위생관리에 대한 실태 조사)

  • Soh, Gowan-Soon;Kim, Yong-Suk;Shin, Dong-Hwa
    • Journal of Food Hygiene and Safety
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    • v.22 no.1
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    • pp.63-75
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    • 2007
  • A survey on sanitary management at 98 food service institutions located in Jeollabuk-Do were conducted. Food service institutions included 13 hospitals, 38 schools, 40 enterprises, and 7 others. The sterilization in boiling water was used for disinfection of tableware, spoon and chopsticks, and dish towel. Cooking kit, refrigerator, chopping board, and knife were sterilized with disinfectant. Frequency of sanitary training program on employees was 56.1% for 1 time/month, 12.2% for 2-3 times/month, and 11.3% for 1 time/week. Preparing ratio of defrosting, warehouse and rest room, and washing and sterilization diary were 73.8, 60.5, and 54.5%, respectively. However, checking ratio of environments (9.5%), personal sanitation (10.8%), and sanitary training program diary(8.4%) were low. Major obstacle factors on the introduction of Hazard analysis critical control point (HACCP) system into food service institutions were lack of equipment and facilities (54.1%) and lack of understanding and data on HACCP system (17.3%). Therefore, in order to reduce the outbreak of food-borne diseases increasing frequency, we estimated that the introduction of sanitary management system and the conversion of dietician' perception on sanitary managements in food service institutions were needed.

Bactericidal Efficacy of a Disinfectant Spray Containing a Grapefruit-seed Extract, Citric acid, Malic acid and Benzalkonium Chloride against Salmonella Typhimurium and Brucella ovis

  • Cha, Chun-Nam;Park, Eun-Kee;Jung, Ji-Youn;Yoo, Chang-Yeul;Kim, Suk;Lee, Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.31 no.4
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    • pp.299-303
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    • 2016
  • Salmonella spp. and Brucella spp. can cause considerable diseases on both humans and animals. In addition, these microorganisms cause the economic loss in animal farming and food industry. In this study, the disinfection efficacy of a disinfectant spray, composed to grapefruit seed extract, citric acid, malic acid and benzalkonium chloride, was evaluated against S. Typhimurium and B. ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at $4^{\circ}C$. The disinfectant and test bacteria were diluted with hard water (HW) or organic matter suspension (OM) according to treatment condition. On HW condition, the bactericidal activity of the disinfectant spray against S. Typhimurium and B. ovis was 5 and 4 fold dilutions, respectively. On OM condition, the bactericidal activity of the disinfectant spray was 2 and 1 fold dilutions against S. Typhimurium and B. ovis, respectively. As the disinfectant spray possesses bactericidal efficacy against foodborne pathogens such as S. Typhimurium and B. ovis, the disinfectant spray can be used to control the spread of bacterial diseases.

Quantitative Cell Count of Vibrio vulnificus Cells Based on MPN-PCR Method (MPN-PCR 방법을 이용한 Vibrio vulnificus 균수 정량분석)

  • Jang, Yu-Mi;Park, Seul-Ki;Jeong, Hee-Jin;Lee, Jang-Won;Yoon, Yohan;Park, Kwon-Sam;Shin, Il-Shik;Kim, Young-Mog
    • Journal of Food Hygiene and Safety
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    • v.33 no.5
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    • pp.412-415
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    • 2018
  • The objective of this study was to establish a quantitative count method of Vibrio vulnificus cells. Plate count method is often used to count the number of V. vulnificus cells using thiosulfate citrate bile salts sucrose (TCBS) agar plate. However, this method is unsuitable for counting V. vulnificus cells due to growth inhibition and cell injuries in TCBS medium. In this study, we suggested a most probable number-polymerase chain reaction (MPN-PCR) method using alkaline peptone water medium for the quantification of V. vulnificus. This MPN-PCR method showed 2 log higher cell number than TCBS agar plate method. Similar results were also found in the control using, Luria-Bertani agar containing 2% NaCl. Thus, this MPN-PCR method can be used a sensitive method for quantitative count of viable V. vulnificus cells in fish and shellfish samples.

Phototaxis of Fish (2) - Response of Rook bream and Grass puffer to the white lights - (어류의 주광성에 관한 연구 (2) - 백색광에 대한 돌돔과 복섬의 반응 -)

  • 양용림
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.16 no.1
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    • pp.27-35
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    • 1980
  • The purpose of the present study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in' daytime and at night by using two species of commercial fishes: rock bream, Oplegnathus fasciatus(Temminet et Schlegel) and glass-puffer,\ulcorner Fugu.niphobles (Jordan \ulcorneret. Snyder). An experimental tank($360L{\times}50W{\times}55H cm$) was set up in a dark room. An illumination system was attached to one end of the tank to control horizontal light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the. experiment water depth was maintained 50 em level in the tank. The tank was marked into six longitudinal sections each, being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 40 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted40 times every 30 seconds, and the gathering rates were obtain from th~ average number of. fish' in each section. The light intensity inducing maximum gathering rate is as follows: rock bream: 162.0 lux (104,3--238, 1 lux) (day), 162.0 lux (104.3--238.1 lux) (night). grass puffer: 16.6 lux (10.6--24.5 lux) (day), 1. 9 lux (1. 2-2. 9 lUX) (night). Trend .of the gathering rate in illumination time revealed different results in two fish species. Gathering rate of rock bream showed the increasing trend fluctuately with the lapse of ' illumination time. However, that of grass puffer showed the increasing trend gradually at the early period of the illumination time and the uniform trend at the latter period with little distictive fluctuation.

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Improvements Caused by Silk Sericin Extract Derived from Silkworm in Blood Glucose and Lipid Concentration in Diabetic Rats (누에 유래 실크 세리신이 당뇨성 흰쥐의 혈당 및 지질 농도 개선에 미치는 영향)

  • Kim, Han-Soo;Seong, Jong-Hwan;Lee, Young-Guen;Xie, Cheng-Liang;Shin, Ji-Moon;Yoon, Ho-Dong
    • The Korean Journal of Food And Nutrition
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    • v.23 no.3
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    • pp.392-398
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    • 2010
  • The objective of this study was to assess improvements caused by silk sericin extract in blood glucose and lipid concentrations in the sera of streptozotocin(STZ, 55 mg/kg B.W., I.P. injection)-induced diabetic rats fed on experimental diets for 5 weeks. Serum concentrations of blood glucose, total cholesterol, atherosclerotic index, LDL, LDL-cholesterol, free cholesterol, cholesteryl ester ratio, triglyceride(TG) and phospholipids(PL) were remarkably higher in the diabetic group(group BSW) and STZ(I.P.)-plus-silk sericin extract group(group ESS) than in the control group(group CG, basal diet-plus-water). However, the serum concentrations of blood glucose, total cholesterol, atherosclerotic index, LDL, LDL-cholesterol, free cholesterol, cholesteryl ester ratio, TG and PL were lower in the ESS group than in the BSW group, whereas the ratio of HDL-cholesterol concentration to total cholesterol and HDL-cholesterol concentration in the ESS group were higher than in the BSW group. The activities of alkaline phosphatase(ALP) and aminotransferase(AST, ALT) in serum were lower in the ESS group than in the diabetic BSW group. The results shown above suggested that silk sericin extract effectively improves blood glucose and lipid concentrations in the sera of STZ-induced diabetic rats.

Effects of Salt, Glucono-${\delta}$-Lactone and High Pressure Treatment on Physico-Chemical Properties of Restructured Pork (소금과 Glucono-${\delta}$-Lactone의 첨가 및 초고압 처리가 재구성 돈육의 이화학적 특성에 미치는 효과)

  • Bong Geun-Pyo;Park Sung-Hee;Kim Jee-Yeon;Ko Se-Hee;Min Sang-Gi
    • Food Science of Animal Resources
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    • v.26 no.2
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    • pp.204-211
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    • 2006
  • This study investigated the effect of salt and glucono-${\delta}$-lactone (GdL) on the cold-set binding of restructured pork washed and pressurized at 200 MPa. Binding strength, PH, water holding capacity (WHC) and color were determined. NaCl improved pH, WHC and binding strength. GdL also increased binding strength while decreased WHC and pH significantly (p<0.05). However, low GdL level combined with NaCl showed high pH and WHC, compared to control. In color, NaCl decreased $L^*$-value with increasing $a^*$-value significantly (p<0.05). In contrast to NaCl, GdL increased $L^*$-value and decreased $a^*$-value. GdL tended to decrease $b^*$-value and significant differences were found when GdL was added above 1%. Pearson's correlation coefficients presented that NaCl had a significant effect on binding strength (0.6632) and lightness (-0.7330) while GdL had a significant correlation with all parameters barring binding strength. The results indicated that under washing and pressure treatments, GdL had a potential effect on cold-set binding with reducing NaCl concentration, especially when low GdL concentration combined with NaCl was added.

Development of U-shaped Arterialvenous Shunt Using Porous Polyurethane (다공성 폴리우레탄을 이용한 동정맥 누관의 개발)

  • 정재승;김희찬;박광석;최진욱;민병구
    • Journal of Biomedical Engineering Research
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    • v.20 no.2
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    • pp.221-230
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    • 1999
  • A new technique for the preparation of porous polyurethane vascular prostheses was investigated. Synthetic vascular grafts with porous wall have been widely proposed, claiming that strength, suture retention, kink resistance, and other handling properties are improved over those with nonporous solid wall. Related to these facts, the control of pores and compliance match have been very important and interesting issues. Two kinds of polymer sheets were compared. One was the porous PU-sheet made at room temerature by the solvent/non-solvent exchange. And the other was the porous PU-sheet fabricated by thermal phase transition and solvent/non-solvent exchange in the thermal controlled bath. According to the result of the above experiments, polyurethane solution was injected into a mold designed for U-type graft. After freezing at low temperature, solvent was dissolved out with alcohol at < $0^{\circ}C$ and water at room temperature to form porous vessels. The average pore size and pore occupation were easily changed by changing polyurethane concentration and freezing rate. This technique can give a proper pore size for tissue ingrowth, and suitable compliances for matching with arteries and veins. In addition, the fabrication of more complicated shaped vessels such as the U-type vascular grafts is easily controlled by using a mold. This method might give a desired compliact graft for artificial implantaion with the commercially available medical polymers.

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Effects of Sediment and Cyanobacterium Microcystis aeruginosa on the Feeding Behavior of Omnivores Gold Fish Carassius auratus (잡식어 붕어의 섭식활동에 퇴적물 및 독성 남조 Microcystis aeruginosa의 영향)

  • Kim, Baik-Ho;Kim, Keun-Hee;Kim, Yong-Jae;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.212-220
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    • 2010
  • Effects of sediment and toxic cyanobacterium Microcystis aeruginosa on feeding behaviors of an omnivorous fish, gold fish (Carassius auratus) were examined in laboratory and in situ mesocosm. Laboratory feeding experiments were performed in small aquaria (7 L) with cyanobacterial blooms (mainly M. aeruginosa) under the condition of sediments and no-sediments, and toxic (NIES-298) and non-toxic M. aeruginosa (NIES-101). In situ feeding experiments were conducted at the shore of eutrophic lake (Lake Ilgam, Seoul) in the mid-July, 2005. Results showed that fish introduction decreased the concentration of Chlorophyll-a (Chl-a) at higher rate in no sediment-containing aquaria. In contrast, there was a drastic increase of Chl-a in the sedimentcontaining aquaria. Fish effectively removed the M. aeruginosa cells without algal toxin (microcystin). Fish also selectively removed the large size Chl-a (>$50{\mu}m$), although all kinds of nutrients were increased after fish introduction, especially ammonia. Our results indicate that the strategic introduction of domestic omnivores Carassius auratus, to control cyanobacterial bloom in eutrophic lake will negatively play in the water quality improvement via a sediment disturbance and a density-dependent digestion.