• Title/Summary/Keyword: natural barrier

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A Study on the Sanitation Management Status and Barriers to HACCP System Implementation of School Foodservice Institutions in Seoul Metropolitan Area (수도권 지역 학교급식소의 위생관리 현황 및 HACCP 시스템 적용 장애요인 연구)

  • Kim, Gyoung-Mi;Lee, Sim-Yeol
    • Korean Journal of Community Nutrition
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    • v.13 no.3
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    • pp.405-417
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    • 2008
  • The purpose of the study was to investigate the sanitation management status and implementation barriers of the HACCP system. A survey was conducted based on 760 schools through e-mail after having gone through phone interviews to dieticians in Seoul, Gyeonggi and Incheon areas from December 2006 to March 2007. The following statistics were drawn out from the 459 surveys out of the 760, thus giving a response rate of 60.4% (N = 459). The statistical data analysis was completed using the SPSS program. 92.6% of the respondents operated sanitary education once a month and 67.1 % used internet as their sanitary educational source. 50.5% of the pre-preparation rooms were not divided and 78.0% of kitchen floors were always kept wet. Only 15.7% of the respondents used heat and cold insulators and 73.2% of drinking water was natural or purified water. 60.3% of food trays were electronically sterilized and 70.2% of spoons and chopsticks were sterilized by boiling water. The main cause of food-borne diseases was the lack of facilities and equipment (33.1%). Also, the deficiency of facilities and equipment (4.07 points) acted as an implementation barrier of the HACCP system. Compared to Gyeonggi or Incheon area results, Seoul's facilities and equipment (p < 0.001) and implementing barriers of the HACCP system (p < 0.001) results came out relatively high. After the analysis of the implementation barriers of the HACCP system, 91.7% of school principals said it was difficult to apply the HACCP system due to lack of financial support. In consideration to the school foodservice support, solutions for the facilities of school foodservice and a systematic sanitary education of the HACCP system must be made for the employees and everyone else who are related.

Assessment on the Flame Retardancy for Polyethylene/Montmorillonite Nanocomposite (Polyethylene/Montmorillonite Nanocomposite의 난연성 평가)

  • Song, Young-Ho;Chung, Kook-Sam
    • Fire Science and Engineering
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    • v.20 no.4 s.64
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    • pp.72-76
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    • 2006
  • Polymer/clay nanocomposites have generated considerable interests in the past decade because adding just tiny amount of clay to the polymer matrix could produce a dramatic enhancement in physical, thermal and mechanical properties. Smectite clays, such as montmorillonite (MMT), are of great industrial value because of their high aspect ratio, plate morphology, intercalative capacity, natural abundance and low cost. In this study, PE/MMT nanocomposites were directly prepared by melt intercalating PE and the modified clay. The nanostructure was verified by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and their flame retardant properties were measured and discussed by limiting oxygen index (LOI), char yield and smoke mass concentration. And their thermal stabilities were measured by differential thermogravimetric (DTG) and thermogravimetric analysis (TGA). The PE/MMT nanocomposites proved more effective the conventional composites in reinforcement. Two functions in the thermal stability of the PE/MMT nanocomposite, one is the barrier effect to improve the thermal stability, and another is catalysis, leading to a decrease of the thermal stability. The flammability was greatly decreased due to the formation of the clay-enriched protective char during the combustion.

Effect of the concentrated-diatom of Caloneis schroederi and Rhaphoneis sp. for seedling production of Haliotis discus hannai (북방전복 종묘생산을 위한 농축 규조류 Caloneis schroederi와 Rhaphoneis sp.의 효과)

  • Kim, Seung-Hyern;Kim, Mi Jeong;Park, Se Jin;Hur, Sung Bum
    • The Korean Journal of Malacology
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    • v.29 no.3
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    • pp.197-205
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    • 2013
  • Even though seedling production of Haliotis discus hannai has fully developed, the culture of benthic diatom as a live food for larvae is still a barrier to solve in commercial hatchery. The farmer depends on mixed microalgae which are non-selectively attached on the plate by flowing of natural seawater. The adequate diatom on the plate for the larvae in terms of quality and quantity is always significant bottleneck in the hatchery. In this study, two benthic diatom species, Caloneis schroederi and Rhaphoneis sp. were separately cultured in mass and inoculated to four tons' settlement tank of the larvae. And the larvae and the spats were cultured for nineteen and nine weeks, respectively. The result on seedling production of H. discus hannai with this method was compared to that of the farmer's traditional method as a control. With regard to variation of species composition of benthic diatom on the plate, C. schroederi and Rhaphoneis sp. were dominant for first three weeks after inoculation. But the diverse diatoms mainly, Navicula, Amphora, Cylindrotheca, Licmophora, Pleurosigma began to attache on the plate from the 4th week. The larvae attached 2.5 times more in C. schroederi tank than in the control tank. The final total biomass of the seeds in Rhaphoneis sp. tank was 3.2 times more than that of the control tank. The retared-spats in the seedling production also showed significantly higher growth and survival in the spat fed Rhaphoneis sp. or C. schroederi than those in the control group. We suggest that C. schroederi is proper for settlement of the larvae and Rhaphoneis sp. is appropriate for the growth of the larvae and spats in the commercial hatchery of H. discus hannai.

The Use of Unmanned Aerial Vehicle for Monitoring Individuals of Ardeidae Species in Breeding Habitat: A Case study on Natural Monument in Sinjeop-ri, Yeoju, South Korea (백로류 집단번식지의 개체수 모니터링을 위한 무인항공기 활용연구 - 천연기념물 209호 여주 신접리 백로와 왜가리 번식지를 대상으로 -)

  • Park, Hyun-Chul;Kil, Sung-Ho;Seo, Ok-Ha
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.1
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    • pp.73-84
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    • 2019
  • In this research, it is a basic study to investigate the population of birds using UAVs. The research area is Ardeidae species(ASP) habitat and has long-term monitoring. The purpose of the study is to compare the ASP populations which analyzed ground observational survey and UAVs imagery. We used DJI's Mavic pro and Phantom4 for this research. Before investigating the population of ASP, we measured the escape distance by the UAVs, and the escape distances of the two UAVs models were statistically significant. Such a result would be different in UAV size and rotor(rotary wing) noise. The population of ASP who analyzed the ground observation and UAVs imagery count differed greatly. In detail, the population(mean) on the ground observation was 174.9, and the UAVs was 247.1 ~ 249.9. As a result of analyzing the UAVs imagery, These results indicate that the lower the UAVs camera altitude, the higher the ASP population, and the lower the UAVs camera altitude, the higher the resolution of the images and the better the reading of the individual of ASP. And we confirmed analyzed images taken at various altitudes, the individuals of ASP was not statistically significant. This is because the resolution of the phantom was superior to that of mavic pro. Our research is fundamental compared to similar studies. However, long-term monitoring for ASP of South Korea's by ground observation is a barrier of the reliability of the monitoring result. We suggested how to use UAVs which can improve long-term monitoring for ASP habitat.

Korean Red Ginseng attenuates ultraviolet-mediated inflammasome activation in keratinocytes

  • Ahn, Huijeong;Han, Byung-Cheol;Hong, Eui-Ju;An, Beum-Soo;Lee, Eunsong;Lee, Seung-Ho;Lee, Geun-Shik
    • Journal of Ginseng Research
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    • v.45 no.3
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    • pp.456-463
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    • 2021
  • Background: Keratinocytes form a physical barrier and act as an innate immune cell in skin. Keratinocytes secrete pro-inflammatory cytokines, such as interleukin (IL)-1β, resulting from inflammasome activation when exposed to ultraviolet (UV) irradiation. Korean Red Ginseng extracts (RGE) have been well-studied as modulators of inflammasome activation in immune cells, such as macrophages. In the study, we elucidated the role of RGE on the UV-mediated inflammasome activation in keratinocytes compared with that in macrophages. Methods: Human skin keratinocyte cells (HaCaT), human epidermal keratinocytes (HEK), human monocyte-like cells (THP-1), and mouse macrophages were treated with RGE or a saponin fraction (SF) or non-saponin fraction (NS) of RGE before and after UV irradiation. The secretion levels of IL-1β, as an indicator of inflammasome activation, were analyzed. Results: The treatment of RGE or SF in macrophages after UV irradiation inhibited IL-1β secretion, but similar treatment in HaCaT cells did not. However, the treatment of RGE or SF in HaCaT cells in the presence of poly I:C, a toll-like receptor (TLR) 3 ligand, before UV exposure elicited the inhibition of the IL-1β secretion. The inhibition was caused by the disruption by RGE or SF of the TLR mediating up-regulation of the pro-IL-1β and NLRP3 genes during the priming step. Conclusion: RGE and its saponins inhibit IL-1β secretion in response to UV exposure in both keratinocytes and macrophages. In particular, RGE treatment interrupted only the priming step in keratinocytes, although it did attenuate both the priming and activation steps in macrophages.

Effect of Coptidis Rhizoma and Evodiae Fructus Mixture on Esophageal Mucosa in Chronic Reflux Esophagitis (만성 역류성 식도염에서 황련과 오수유 혼합물이 식도 점막에 미치는 효과)

  • Lee, Jin A;Shin, Mi-rae;Lee, Ji Hye;Roh, Seong-soo
    • Korean Journal of Pharmacognosy
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    • v.51 no.4
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    • pp.349-359
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    • 2020
  • Gastroesophageal reflux disease (GERD) is a disease that stomach contents continually refluxing, and is currently on the rise worldwide. The purpose of this study is to find natural materials that can reduce side effects and effectively treat chronic acid reflux esophagitis (CARE), one of GERD. First, the antioxidant activity was confirmed by varying the mixing ratio of Coptidis Rhizoma and Evodiae Fructus, which are effective against chronic reflux esophagitis. After, animal experiments were conducted using a 1:1 (CE) and 1:2 (CEE) combination ratio of Coptidis Rhizoma and Evodiae Fructus, which had the best antioxidant efficacy. Gross lesion of esophageal mucosa after CE or CEE treatment showed a superior enhancement compared with that of CARE control rats. Additionally, its inhibited MAPK phosphorylation and led NF-κB inactivation through the suppression of IκBα phosporylation by regulating Nrf2/Keap-1, and NF-κB inactivation induced reduced protein expressions including inflammatory mediators and cytokines. Moreover, its improved esophageal barrier function through upregulating protein expressions of tight junction protein, whereas downregulating protein expressions of MMPs. Taken together, a mixture of Coptidis Rhizoma and Evodiae Fructus can attenuate the esophageal mucosal ulcer by inhibiting MAPK and NF-κB pathway, and upregulating proteins associated with tight junction.

Ginsenoside Rd protects cerebral endothelial cells from oxygen-glucose deprivation/reoxygenation induced pyroptosis via inhibiting SLC5A1 mediated sodium influx

  • Li, Suping;Yu, Nengwei;Xu, Fei;Yu, Liang;Yu, Qian;Fu, Jing
    • Journal of Ginseng Research
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    • v.46 no.5
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    • pp.700-709
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    • 2022
  • Background: Ginsenoside Rd is a natural compound with promising neuroprotective effects. However, the underlying mechanisms are still not well-understood. In this study, we explored whether ginsenoside Rd exerts protective effects on cerebral endothelial cells after oxygen-glucose deprivation/reoxygenation (OGD/R) treatment and its potential docking proteins related to the underlying regulations. Method: Commercially available primary human brain microvessel endothelial cells (HBMECs) were used for in vitro OGD/R studies. Cell viability, pyroptosis-associated protein expression and tight junction protein degradation were evaluated. Molecular docking proteins were predicted. Subsequent surface plasmon resonance (SPR) technology was utilized for validation. Flow cytometry was performed to quantify caspase-1 positive and PI positive (caspase-1+/PI+) pyroptotic cells. Results: Ginsenoside Rd treatment attenuated OGD/R-induced damage of blood-brain barrier (BBB) integrity in vitro. It suppressed NLRP3 inflammasome activation (increased expression of NLRP3, cleaved caspase-1, IL-1β and GSDMD-N terminal (NT)) and subsequent cellular pyroptosis (caspase-1+/PI + cells). Ginsenoside Rd interacted with SLC5A1 with a high affinity and reduced OGD/R-induced sodium influx and potassium efflux in HBMECs. Inhibiting SLC5A1 using phlorizin suppressed OGD/R-activated NLRP3 inflammasome and pyroptosis in HBMECs. Conclusion: Ginsenoside Rd protects HBMECs from OGD/R-induced injury partially via binding to SLC5A1, reducing OGD/R-induced sodium influx and potassium efflux, thereby alleviating NLRP3 inflammasome activation and pyroptosis.

Assessment of Cryogenic Material Properties of R-PUF Used in the CCS of an LNG Carrier

  • Song, Ha-Cheol
    • Journal of Ocean Engineering and Technology
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    • v.36 no.4
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    • pp.217-231
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    • 2022
  • Reinforced polyurethane foam (R-PUF), a material for liquefied natural gas cargo containment systems, is expected to have different mechanical properties depending on its stacking position of foaming as the glass fiber reinforcement of R-PUF sinks inside R-PUF under the influence of gravity. In addition, since R-PUF is not a homogeneous material, it is also expected that the coordinate direction within this material has a great correlation with the mechanical properties. So, this study was conducted to confirm this correlation with the one between the mechanical properties and the stacking position. In particular, in this study, R-PUF of 3 different densities (130, 170, and 210 kg/m3) was used, and tensile, compression, and shear tests of this material were performed under 5 temperatures. As a result of the tests, it was confirmed that the strength and modulus of elasticity of the material increased as the temperature decreased. Specifically, the strength and modulus of elasticity in the Z direction, which was the lamination direction, tended to be lower than those in the other directions. Finally, the strength and elastic modulus of different specimens of the material found at the bottom of their lamination compared to the specimens with these properties found at positions other than their lamination bottom were evaluated. Further analysis confirmed that as the temperature decreased, hardening of R-PUF occurred, indicating that the strength and modulus of elasticity increased. On the other hand, as the density of R-PUF increased, a sharp increase in strength and elastic modulus of R-PUF was observed.

Current status of interprofessional education learning activities in wards provided by tertiary hospitals and secondary general hospitals and barriers

  • Kang, Joonsung;Sin, Hye Yeon
    • Korean Journal of Clinical Pharmacy
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    • v.32 no.2
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    • pp.106-115
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    • 2022
  • Background: The World Health Organization (WHO) has focused on the need for interprofessional education (IPE) to improve interprofessional collaboration competency and patient health outcomes. Accordingly, most European and North American medical colleges have established IPE for students. However, IPE learning activity in medical wards for the clinical experience of pharmacy students has not been fully reviewed in Korea. Therefore, this study aims to examine the current status of IPE learning activities in wards at tertiary and secondary hospitals in order to identify ways to improve the program. Methods: The official document of cooperation consists of six self-administered questions regarding IPE learning activities in wards. The preceptor's response in each hospital was evaluated. Results: Of the 22 hospitals, 9 tertiary hospitals and 12 secondary general hospitals responded. For the introductory pharmacy practice experience (IPPE), participating in intensive care (IC) was provided at one secondary general hospital (8.3%) and no tertiary hospital. Ward rounds with medical staff members were provided at two tertiary hospitals (22.2%) and one (8.3%) secondary general hospital. A major barrier to executing IPE was lack of rewards and incentives for the faculty and preceptors who participated in the program. Conclusion: In both tertiary hospitals and secondary general hospitals, pharmacy students have limited exposure to IPE learning activities in wards at hospital, and IPPE at most hospitals was carried out in pharmacy settings only. This study suggests that it is necessary for the hospitals to improve and support IPE learning activities in wards in order to improve learners' competency.

Anti-inflammatory Effect of Biotin and Plant extracts

  • Y. J. Joo;S. W. Jung;Kim, B. R.;Kim, I. Y.;Lee, J. D.;H. C. Ryoo;Lee, S. H.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.601-610
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    • 2003
  • Biotin is a water-soluble vitamin used as a skin conditioning agent and promotes the formation of intercellular lipid layers through increased lipid synthesis, which improves the skin's natural barrier function. The anti-inflammatory effects of biotin have been investigated using in vitro assay models, such as MTT assay, measurements of concentrations of nitric oxide(NO), prostaglandin E2(PGE$_2$), and inhibition rate of 5-lipoxygenase(5-LOX). In comparison with biotin, other plant extracts were tested at the same time which were kudzu vine extract, sage extract, paeonia extract, and dipotassium glycyrrhetinate. Nitric oxide is a signal molecule with functions such as neurotransmission, local vascular relaxation, and anti-inflammation in many physiological and pathological processes. NO can cause apoptosis and necrosis of target cells such as keratinocytes and is generated from L-arginine by nitric oxide synthase (NOS). Prostanoids, including prostaglandins and thromboxanes, are generated by the phospholipase $A_2$/cyclooxygenase(COX) pathway, and leukotrienes are generated by the 5-lipoxygenase pathway from arachidonic acid. Prostaglandin E2 recently have been shown to be beneficial in the resolution of tissue injury and inflammation, also has been implicated as an immunosuppressive agent and plasma levels of PGE$_2$ are elevated in patients sustaining thermal injury. Lipoxygenase metabolites from arachidonic acid have been implicated in inflammation, anti-inflammatory activity of the raw materials was evaluated in vitro by the offered inhibition of lipoxygenase.

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