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Alginate/Carboxymethyl Scleroglucan Hydrogels for Controlled Release of Protein Drugs

  • Lee, Chang-Moon;Jeong, Hwan-Jeong;Kim, Dong-Woon;Lee, Ki-Young
    • Macromolecular Research
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    • v.16 no.5
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    • pp.429-433
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    • 2008
  • Alginate/carboxymethyl scleroglucan (CMSG) hydrogels were suggested as a novel carrier for the controlled release of protein drugs. The drug release characteristics of alginate hydrogels were improved by CMSG addition. Scleroglucan (Sclg) was carboxymethylated using monochloroacetic acid in aqueous alkaline medium. Alginate/CMSG hydrogels were prepared by dropping the mixture solution of alginate/CMSG into calcium chloride solution. The swelling behaviors and drug release characteristics of the hydrogels were investigated in the buffers of pH 1.2 or 7.4. As the CMSG content increased in the hydrogels, the swelling ratio of the alginate/CMSG hydrogel increased rapidly in the buffer of pH 7.4. At pH 1.2, however, the swelling ratio significantly decreased compared to that at pH 7.4. According to in vitro release tests, only 15% of ovalbumin, investigated as a model protein drug, was released from the alginate/CMSG hydrogels at pH 1.2 within 6 h. At pH 7.4, however, the drug release significantly increased due to the rapid swelling of the hydrogels. The release and swelling behaviors of the hydrogels could be controlled by changing the CMSG content in the hydrogels. These results supported the use of alginate/CMSG hydrogels as a suitable carrier for the controlled release of protein drugs in a pH responsive manner.

Prediction for Possibility of the Electric Fire by Tracking Breakdown (트래킹에 의한 전기화재 가능성 예측)

  • Jee, Seung-Wook
    • Fire Science and Engineering
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    • v.29 no.2
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    • pp.1-7
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    • 2015
  • Tracking, which is one of main reasons of the electric fire, progresses gradually, and therefore, the possibility of fire caused by tracking can be predicted by analyzing the stage of its progress. This paper is conducted in order to predict possibility of the electric fire caused by the tracking in the simulated electric equipment with load. Non-inductive resistance is used as the load. The tracking is happened in a Polyvinyl-chloride-sheathed flat cord, which is a part of the simulated electric equipment by means of dropping of electrolyte droplet. In order to predict the possibility of electric fire caused by tracking, we detect the whole current waveforms of the simulated electric equipment. The time-energy analysis and probability distribution are used for analysis of the tracking progress from the whole current waveforms. In accordance with the results is used for input date of Neural networks, the neural networks can be predict possibility of the electric fire in the electric equipment by 4 stages.

A Study on the Propagation Characteristics of Fire Alarm Sound in Buildings (화재비상경보음의 건물 내 전달특성에 관한 연구)

  • Baek, Eun-Sun
    • Fire Science and Engineering
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    • v.23 no.5
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    • pp.153-160
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    • 2009
  • This study aims to review the propagation characteristics of fire alarm sound in building through computer simulation. In order to achieve this goal, the sound power level of existing three different emergency alarms were measured in an anechoic chamber. Sound power level of alarm bell was 98.6dB and electronic-siren speaker was 95.7dB, and electronic-siren phon was 101.8dB at the voltage of DC 24V in the condition of anechoic chamber. As the results of acoustic simulation, it was shown that sound levels at the corridor of the building were relatively high and even. But, there were large difference in sound level at all the frequency bands between corridor and lecture rooms. This mean that alarm sound couldn't be recognized sometimes in lecture rooms. Through the computer simulation, the propagation characteristics of fire alarm sound could be forecasted and compared due to plans of buildings.

Effect of Tongqiao-tang on OVA Induced Allergic Rhinitis Mouse Model

  • Lee, Kyu-Jin;Nam, Hae-Jeong;Kim, Yoon-Bum
    • The Journal of Korean Medicine
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    • v.29 no.5
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    • pp.96-103
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    • 2008
  • Objectives : Tongqiao-tang(TQT) has been commonly used for the treatment of common cold, rhinitis etc. Nowadays, TQT becomes one of the most frequently used medicines for allergic rhinitis, but the mechanism of TQT in vivo isn't investigated yet. This study was performed to investigate the effect of TQT on OVA-induced allergic rhinitis mouse model by calculating serum cytokines and IgE. Methods : 8 weeks aged male BALB/c mice were divided into three groups: the normal group, the control group and the medicated group (the TQT group). Each group was consisted of 15 mice. The TQT group was administered TQT extract orally one time a day (1g/kg) from the $1^{st}$ day of experiment till the $26^{th}$ day. The control group and the normal group were administered normal saline by the same method of the TQT group. To induce the allergic rhinitis in the control group and the TQT group, mice of each group were sensitized intraperitoneally with ovalbumin (OVA) solution at the $1^{st}$, the $7^{th}$ and the $14^{th}$ day. After then, intranasal sensitization was performed by dropping 0.1% OVA solution in nasal cavity at the $22^{th}$, the $24^{th}$ and the $26^{th}$ day. At the $27^{th}$ day, the mice were killed and the changes of interferon-${\gamma}$, interleukin-4, interleukin-5, total IgE and OVA-specific IgE were checked. Results : IFN-${\gamma}$ was increased 36% more in the TQT group than that in the control group. IL-4, IL-5, the total IgE and OVA-specific IgE were decreased in the TQT group as compared with the control group and these results were statistically significant. Conclusions : Considering the above experimental results, this study showed that TQT could reduce the allergic reaction in allergic rhinitis. Advanced studies are required to investigate the further mechanisms of TQT.

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The Anti-inflammatory Effect of Cheongyeonsan for Allergic Rhinitis (알러지성 비염에 대한 청연산 추출물의 항염증효과)

  • Kim, Jeong Won;Ahn, Sang Hyun;Kim, Ki Bong
    • The Journal of Pediatrics of Korean Medicine
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    • v.32 no.1
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    • pp.19-29
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    • 2018
  • Objectives This study investigated the effects of Cheongyeonsan for allergic rhinitis. Methods First, the GS/MS was used to analyze the effects of Cheongyeonsan by measuring inflammatory markers. Second, 3 groups of 10 6-week-old BALB/c mice were divided into Ctrl (no treatment), ARE (allergic rhinitis-induced without treatment), and CRT (allergic rhinitis-induced after Cheongyeonsan treatment) groups. Ovalbumin (OVA) was used as an antigen to induce allergic rhinitis and sensitization was performed by intraperitoneal injection of 0.1% OVA solution 21, 14, and 7 days before the onset of allergic rhinitis. Allergic rhinitis was induced by dropping OVA solution on the nasal cavity of each mouse for 5 days after the last sensitization. Seven days after the first induction, second induction was introduced by the same method. After making the section, MMP-9, substance P, $TNF-{\alpha}$, $NF-{\kappa}B$ p65, COX-2, iNOS and Nrf, apoptotic cells were observed by Masson trichrome staining, immunohistochemical staining, TUNEL of nasal mucosal tissues of each group. Results GC/MS results showed undecanoic acid. Masson trichrome results showed that the CRT group had less respiratory epithelial damage. Immunohistochemical staining showed CRT group had 58% decrease in MMP-9, 61% decrease in substance P, 55% decrease in $TNF-{\alpha}$, 38% decrease in $NF-{\kappa}B$ p65, 53% decrease in COX-2, 54% decrease in iNOS, 87% increase in Nrf compared to those of the ARE group. TUNEL showed a positive reaction of 84% increase in apoptotic cells greater than that of the ARE group. Conclusions Cheongyeonsan alleviates nasal mucosal damage and reduces inflammatory mediators from allergic rhinitis-induced mice.

Ability of children to perform touchscreen gestures and follow prompting techniques when using mobile apps

  • Yadav, Savita;Chakraborty, Pinaki;Kaul, Arshia;Pooja, Pooja;Gupta, Bhavya;Garg, Anchal
    • Clinical and Experimental Pediatrics
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    • v.63 no.6
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    • pp.232-236
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    • 2020
  • Background: Children today get access to smartphones at an early age. However, their ability to use mobile apps has not yet been studied in detail. Purpose: This study aimed to assess the ability of children aged 2-8 years to perform touchscreen gestures and follow prompting techniques, i.e., ways apps provide instructions on how to use them. Methods: We developed one mobile app to test the ability of children to perform various touchscreen gestures and another mobile app to test their ability to follow various prompting techniques. We used these apps in this study of 90 children in a kindergarten and a primary school in New Delhi in July 2019. We noted the touchscreen gestures that the children could perform and the most sophisticated prompting technique that they could follow. Results: Two- and 3-year-old children could not follow any prompting technique and only a minority (27%) could tap the touchscreen at an intended place. Four- to 6-year-old children could perform simple gestures like a tap and slide (57%) and follow instructions provided through animation (63%). Seven- and 8-year-old children could perform more sophisticated gestures like dragging and dropping (30%) and follow instructions provided in audio and video formats (34%). We observed a significant difference between the number of touchscreen gestures that the children could perform and the number of prompting techniques that they could follow (F=544.0407, P<0.05). No significant difference was observed in the performance of female versus male children (P>0.05). Conclusion: Children gradually learn to use mobile apps beginning at 2 years of age. They become comfortable performing single-finger gestures and following nontextual prompting techniques by 8 years of age. We recommend that these results be considered in the development of mobile apps for children.

Retailer's Store Brand Product Line Design and Product Assortment Decision in the Vertically Differentiated Product Category (수직적으로 차별화된 제품 카테고리 내에서 소매상의 스토어 브랜드 제품군 디자인 및 제품구색에 대한 의사결정)

  • Chung, Hwan
    • Journal of the Korean Operations Research and Management Science Society
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    • v.36 no.3
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    • pp.107-120
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    • 2011
  • The increased availability of store brand suppliers now provides retailers with opportunities to create their own lines of vertically differentiated multiple store brands within a product category. As the number of store brands increase, the retailer's shelf space becomes more crowded, which may force the retailer to consider dropping some national brands from its assortment. Despite these trends, the problem of product line design in a vertically differentiated product category has been analyzed mainly from a manufacturer's perspective in the marketing literature and it is not known to what extent the findings of the existing product line design literature provide applicable strategic guidelines for the new problem faced by retailers. In this study, we address this deficiency in the literature and conduct an in-depth study of the retailer's strategic design of a line of store brands and its assortment decision within the context of retail category management. We analyze the retailer's decision about not only how to design a line of store brands but also which national brand to drop from its assortment. The results of our analysis are as follows. First, if the retailer has to drop one of national brands from its assortment, it is the best for the retailer to drop the low-quality national brand rather than the high-quality national brand. Second, the retailer has to position the high-quality store brand relatively close to the high-quality national brand, remained on its shelf, in terms of quality so as to maximize the size of retail margin from the national brand. On the other hand, the retailer should set the quality of the low-quality store brand at a lower level than that of the low-quality national brand to increase the total category demand by attracting more price sensitive consumers. By doing so, the retailer can also minimize cannibalization between two store brands. Lastly, our analysis shows that the introduction of a line of store brands improves consumer welfare by increasing real values of all products on the shelf.

The Holding Power of the Oil Boom Anchor (오일 펜스 Anchor의 파주력)

  • CHANG Duk Jong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.6
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    • pp.743-748
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    • 2003
  • An oil boom was set up in order to contain diffused oil from spills and for the retrenchment of damage caused by oil Pollution. Therefore, the oil boom anchor needed proper holding power to endure high resistance from flowing streams and to secure the oil boom around the spill, and must dredge directly into the seabed when it is dropped and block oil outflow immediately. This study investigated the holding power of the danforth anchor and the coastal fishing vessel anchor used for oil booms in the KMPRC (Korea Marine Pollution Response Corporation). For each type, a 30 kg and 20 kg anchor were used. The holding power of the danforth anchors were measured by dropping both weights 10 times. However the coastal fishing vessel anchors were dropped only 5 times each, because no substantial differences were found between drops. In the results of the danforth anchors, an anchor awoke occurred in 2 drops of the 30 kg anchor and in 4 drops of the 20 kg anchor, wherein there was no holding power to be measured. With exception to the anchor awoke cases, the maximum holding power of the danforth 30 kg and 20 kg anchors was 250-520 kg and 123-233 kg, respectively. In the case of the coastal fishing vessel anchors of 30 kg and 20 kg, throughout the experiment, there was no occurrence of an anchor awoke. For the 30 kg and 20 kg anchors, the maximum holding power was measured to be 209-230 kg and 155-170 kg, respectively. Therefore, the holding power of the coastal fishing vessel anchor was shown to be much poorer than that of the danforth anchor. However, the holding power of the danforth anchor was very unstable. Due to the occurrences of anchor awoke, there was no holding power and the measurement value of maximum holding power showed too much variation among the drop tests. Also, after the maximum holding power was achieved, anchor awoke occurred easily. In the case of the coastal fishing vessel anchor was much more stabile, because there was no anchor awoke and no instance where holding power failed. Also the maximum holding power was reached quickly and almost no variation occurred among the drop tests.

Development of Soybean Sprouter Using Principle of Siphoning (싸이폰원리를 이용한 콩나물 자동재배기 개발)

  • Kim, Joong-Man;Choi, Yong-Bae;Yang, Dong-Kun
    • Korean Journal of Food Science and Technology
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    • v.29 no.3
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    • pp.460-463
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    • 1997
  • One of the major problems in automation of soybean sprouter is watering method. This study was conducted solve this problem. The soybean sprouter consisted of three parts: water-receiving chamber with siphon, water spraying bowl and sprout cultivating bowl. It functions as automatic-watering without manpower and electric power, and is not noisy and has duration. Watering interval, watering time and amount could be controlled by regulation of dropping times/min from a tap. Chlorine contained in tap water is naturally decreased during its (water) storage in the water receiving chamber. Among three types of sprouter (siphon type, wet paper type and water pump type) the siphon type can be used at $25{\sim}30^{\circ}C$ that is the optimum temperature for soybean sprout.

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Rheological Properties of Soymilk and Curd Prepared with Micronized Full-fat Soyflour (콩미세분말로 제조된 두유 및 전두부의 물성)

  • 심재진;서지현;소한섭;유병승;이삼빈
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.1
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    • pp.75-81
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    • 2003
  • Rheological properties of micronized full-fat soyflour (MFS ) milk were determined according to solid content, heat-treatment and type of coagulants. Heat-treated MFS milk showed a pseudoplastic flow pattern. The consistency and flow index of heated MFS milk was greatly affected by increasing the concentration of MFS and/or soy protein isolate (SPI). Apparent viscosity of MFS milk was gradually decreased by heating below 6$0^{\circ}C$, but was drastically increased by raising temperature further. Addition of coagulants and SPI resulted in dropping the temperature that allows to increase apparent viscosity drastically. A coagulant for MFS tofu was formulated based on the gelling Property of a single coagulant. The textural properties of MFS tofu were improved using 7.1% total protein fortified with SPI.