• Title/Summary/Keyword: Effective diffusion

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Evaluations on Deodorization Effect and Anti-oral Microbial Activity of Essential Oil from Pinus koraiensis (잣나무 정유의 소취효과 및 구강균에 대한 항균활성 평가)

  • Hwang, Hyun Jung;Yu, Jung-Sik;Lee, Ha Yeon;Kwon, Dong-Joo;Han, Woong;Heo, Seong-Il;Kim, Sun Young
    • Korean Journal of Plant Resources
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    • v.27 no.1
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    • pp.1-10
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    • 2014
  • Essential oils of various plants have been known for potential biological effects such as antibacterial, antifungal, spasmolytic, antiplasmodial activities and insect-repellent property. Recently, the essential oils have attracted considerable interest in oral disease therapy. This essential oil has been known as being effective on easing sick house syndrome, giving forest aroma therapy effect and acting as repellent against pest. The essential oil of Pinus koraiensi, a native plant from Hongcheon-gun, Gangwon-do, was obtained by hydrodistillation. In light of its medicinal importance, in this study its composition, antibacterial activity and the reducing effect of offensive odor have been analyzed. The composition of essential oil was determined by GC and GC-MS. We have identified 14 compounds, of which 1R-${\alpha}$-pinene (19.38 %), 3-carene (10.21 %), camphene (9.82 %), limonene (9.00 %), bicyclo[2,2,1] heptan-2-ol (8.76 %) and ${\beta}$-phellandrene (7.98 %) were the main components. Essential oils from P. koraiensis, Chamaecyparis obtusa, Abies holophylla and Pinus densiflora were compared in terms of alleviating effect of malodors caused from formaldehyde, ammonia, trimethylamine and methylmercaptan. P. koraiensis essential oil was found to decrease the amounts of ammonia and trimethylamine by 75.17 % and 77.36 %, respectively. Antibacterial activity against Streptococcus mutans and Streptococcus sobrinus, which were known as oral cavity inducer, was investigated using the paper disc agar diffusion method. The inhibition zone was observed against S. mutans (5.97 mm) and S. sobrinus (1.40 mm), respectively. P. koraiensis essential oil shown effective deodorization and inhibitory activity against oral cavity in this study might be potential material in oral sanitary industry.

Physiological Activity of Supercritical Poria cocos back Extract and Its Skin Delivery Application using Epidermal Penetrating Peptide (초임계 복령피 추출물의 생리활성 및 경피투과 펩티드를 이용한 경피 약물전달의 응용)

  • Kim, Min Gi;Park, Su In;An, Gyu Min;Heo, Soo Hyeon;Shin, Moon Sam
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.3
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    • pp.766-778
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    • 2019
  • In this study, Poria cocos bark were extracted by supercritical process, and anti-inflammatory, whitening, and antioxidant effects were measured in comparison with ethanol extract. Also, An effective percutaneous permeation method using a selected formulation of the extract and a drug delivery peptide was proposed. Pachymic acid, known as the anti-cancer and anti-inflammatory compound of the ventricle, is an indicator component and the HPLC analysis shows that the supercritical extract of the pericardium is more than twice that of the Poria cocos bark extract. In order to confirm antioxidative effect of Bombyx mori, DPPH scavenging ability and ABTS scavenging ability test showed that the ethanol extract of Poria cocos Back had lower concentration than the supercritical extract of Poria cocos back. However, RAW 264.7 Measurements of Nitric oxide (NO) production in cells showed lower NO production at the same concentration than the Poria cocos back ethanol extract. In addition, after 72 hours of processing of $20{\mu}g/mL$ of the Poria cocos back extract in B16 melanoma cells, both the intracellular and extracellular melanin extract were effective and the supercritical extract was lower melanin content. No toxicity was observed at the concentration of $800{\mu}g/mL$ in RAW 264.7 cells used in NO production experiments. However, in B16 melanoma cells, even at $50{\mu}g/mL$, both Poria cocos back ethanol extract and supercritical extract showed a survival rate of less than 60%. The liposome formulation and drug delivery peptides were shown to be useful for percutaneous permeation of Supercritical Extract of Poria cocos back using a liposome formulation and a drug delivery peptide. it is expected that there will be great potential for development as a variety of cosmetic materials for Poria cocos back.

A Study on the Effect of Improving Permeability by Injecting a Soil Remediation Agent in the In-situ Remediation Method Using Plasma Blasting, Pneumatic Fracturing, and Vacuum Suction Method (플라즈마 블라스팅, 공압파쇄, 진공추출이 활용된 지중 토양정화공법의 정화제 주입에 따른 투수성 개선 연구)

  • Geun-Chun Lee;Jae-Yong Song;Cha-Won Kang;Hyun-Shic Jang;Bo-An Jang;Yu-Chul Park
    • The Journal of Engineering Geology
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    • v.33 no.3
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    • pp.371-388
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    • 2023
  • A stratum with a complex composition and a distributed low-permeability soil layer is difficult to remediate quickly because the soil remediation does not proceed easily. For efficient purification, the permeability should be improved and the soil remediation agent (H2O2) should be injected into the contaminated section to make sufficient contact with the TPH (Total petroleum hydrocarbons). This study analyzed a method for crack formation and effective delivery of the soil remediation agent based on pneumatic fracturing, plasma blasting, and vacuum suction (the PPV method) and compared its improvement effect relative to chemical oxidation. A demonstration test confirmed the effective delivery of the soil remediation agent to a site contaminated with TPH. The injection amount and injection time were monitored to calculate the delivery characteristics and the range of influence, and electrical resistivity surveying qualitatively confirmed changes in the underground environment. Permeability tests also evaluated and compared the permeability changes for each method. The amount of soil remediation agent injected was increased by about 4.74 to 7.48 times in the experimental group (PPV method) compared with the control group (chemical oxidation); the PPV method allowed injection rates per unit time (L/min) about 5.00 to 7.54 times quicker than the control method. Electrical resistivity measurements assessed that in the PPV method, the diffusion of H2O22 and other fluids to the surface soil layer reduced the low resistivity change ratio: the horizontal change ratio between the injection well and the extraction well decreased the resistivity by about 1.12 to 2.38 times. Quantitative evaluation of hydraulic conductivity at the end of the test found that the control group had 21.1% of the original hydraulic conductivity and the experimental group retained 81.3% of the initial value, close to the initial permeability coefficient. Calculated radii of influence based on the survey results showed that the results of the PPV method were improved by 220% on average compared with those of the control group.

The Utility of Immunological Markers and Pulmonary Function Test in the Early Diagnosis of Pulmonary Involvement in the Patients with Rheumatoid Arthritis (류마티스 관절염환자에서 폐침범의 진단에 있어서 면역학적 지표와 폐기능 검사의 유용성)

  • Lee, Dong-Suk;Lee, Chang-Beam;Koh, Hee-Kwan;Moon, Doo-Seop;Lee, Jae-Young;Lee, Kyung-Sang;Yang, Suck-Chul;Yoon, Ho-Joo;Bae, Sang-Cheol;Shin, Dong-Ho;Kim, Seong-Yoon;Park, Sung-Soo;Lee, Jung-Hee
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.6
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    • pp.878-887
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    • 1995
  • Background: It is reported that frequency of pulmonary involvement in the patients with rheumatoid arthritis reaches 10 to 50% and pulmonary involvement is a principal cause of death. As immunology and radiology has developed, interest for the early diagnosis of pulmonary involvement is increasing. Method: Among the patients at Hanyang University Hospital from March, 1990 to July, 1995, we compared the 29 patients having pulmonary involvement with the 18 patients controls in clinical and chest high resolution computed tomography(HRCT) findings by immunological markers and findings of pulmonary function test. We sought useful markers for early diagnosis of pulmonary involvement with noninvasive investigations. Results: The ratio of males to females was 14 : 15 in the group of pulmonary involvement, and all of the 18 patients were females in the control group. Smoking history was 31%(9/29) in the former group and none in the latter group. Rheumatoid factor(RF) was positive in 95.5%(28/29) of the pulmonary involvement group and in 100%(18/18) of the control group(p=0.12). Antiperinuclear factor(APF) showed a significant difference: 86.9%(20/23, average value: 2.0) was positive in the pulmonary involvement group and 50%(8/16, average value: 1.1) in the control group(p=0.04). Antinuclear antibody(ANA) was positive in 60.7%(17/28) of the pulmonary involvement group and in 72.2%(13/18) of the control group(p=0.33). Cryoglobulin also showed a significant difference: 72%(18/25) in the pulmonary involvement group was positive and 56.2%(9/16) in the control group was positive(p=0.02). Bony erosion was positive in 61.5%(16/26) of the pulmonary involvement group and in 77.7%(14/18) of the control group(p=0.8). On the pulmonary function test, the average value of alveolar volume corrected diffusion capacity and residual volume in the pulmonary involvement group and in the control group were 1.07mmol/rnin/KPa(predicted value: 64.2%), 1.32L(predicted value: 70%) and 1.44mmol/min/KPa, 3.75L(predicted value: 86.6%), respectively(p=0.003, p=0.004), showing a significant difference. Conclusion: APF or cryoglobulin on the serological test, the measurement of residual volume and alveolar volume corrected diffusion capacity may be used as effective markers in the diagnosis of pulmonary involvement of the patients with rheumatoid arthritis.

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Analyzing the User Intention of Booth Recommender System in Smart Exhibition Environment (스마트 전시환경에서 부스 추천시스템의 사용자 의도에 관한 조사연구)

  • Choi, Jae Ho;Xiang, Jun-Yong;Moon, Hyun Sil;Choi, Il Young;Kim, Jae Kyeong
    • Journal of Intelligence and Information Systems
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    • v.18 no.3
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    • pp.153-169
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    • 2012
  • Exhibitions have played a key role of effective marketing activity which directly informs services and products to current and potential customers. Through participating in exhibitions, exhibitors have got the opportunity to make face-to-face contact so that they can secure the market share and improve their corporate images. According to this economic importance of exhibitions, show organizers try to adopt a new IT technology for improving their performance, and researchers have also studied services which can improve the satisfaction of visitors through analyzing visit patterns of visitors. Especially, as smart technologies make them monitor activities of visitors in real-time, they have considered booth recommender systems which infer preference of visitors and recommender proper service to them like on-line environment. However, while there are many studies which can improve their performance in the side of new technological development, they have not considered the choice factor of visitors for booth recommender systems. That is, studies for factors which can influence the development direction and effective diffusion of these systems are insufficient. Most of prior studies for the acceptance of new technologies and the continuous intention of use have adopted Technology Acceptance Model (TAM) and Extended Technology Acceptance Model (ETAM). Booth recommender systems may not be new technology because they are similar with commercial recommender systems such as book recommender systems, in the smart exhibition environment, they can be considered new technology. However, for considering the smart exhibition environment beyond TAM, measurements for the intention of reuse should focus on how booth recommender systems can provide correct information to visitors. In this study, through literature reviews, we draw factors which can influence the satisfaction and reuse intention of visitors for booth recommender systems, and design a model to forecast adaptation of visitors for booth recommendation in the exhibition environment. For these purposes, we conduct a survey for visitors who attended DMC Culture Open in November 2011 and experienced booth recommender systems using own smart phone, and examine hypothesis by regression analysis. As a result, factors which can influence the satisfaction of visitors for booth recommender systems are the effectiveness, perceived ease of use, argument quality, serendipity, and so on. Moreover, the satisfaction for booth recommender systems has a positive relationship with the development of reuse intention. For these results, we have some insights for booth recommender systems in the smart exhibition environment. First, this study gives shape to important factors which are considered when they establish strategies which induce visitors to consistently use booth recommender systems. Recently, although show organizers try to improve their performances using new IT technologies, their visitors have not felt the satisfaction from these efforts. At this point, this study can help them to provide services which can improve the satisfaction of visitors and make them last relationship with visitors. On the other hands, this study suggests that they managers along the using time of booth recommender systems. For example, in the early stage of the adoption, they should focus on the argument quality, perceived ease of use, and serendipity, so that improve the acceptance of booth recommender systems. After these stages, they should bridge the differences between expectation and perception for booth recommender systems, and lead continuous uses of visitors. However, this study has some limitations. We only use four factors which can influence the satisfaction of visitors. Therefore, we should development our model to consider important additional factors. And the exhibition in our experiments has small number of booths so that visitors may not need to booth recommender systems. In the future study, we will conduct experiments in the exhibition environment which has a larger scale.

A RURAL HEALTH SERVICE MODEL FOR KOREA BASED OH A PRIMARY CARE NURSING SERVICE SYSTEM

  • Hong, Yeo-Shin
    • Journal of Korean Academy of Nursing
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    • v.11 no.2
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    • pp.5-8
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    • 1981
  • This study concerns itself with the development of a new model of comprehensive health service for rural communities of Korea. The study was conceived to resolve the problems of both underservice in rural communities and underutilization of valuable health manpower, namely the nurses, the disenchanted elite health personnel in Korea. On review of the current situation, the greatest deficiencies in the Korean health care system were found in the availability of primary care at the peripheries of md communities, in the dissemination of knowledge of disease prevention and health care, and in the induction of and guidance for active participation by the clientele in health maintenance at the personal, family and community level Abundant untapped health resources were identified that could be brough to bear upon the national effort to extend health services to every member of the Korean Population. Therefore, it was Postulated that the problem of underservice in rural communities of Korea can be structurcturally resolved by the effective mobilization and organization of untapped health resources, and that. a primary care Nursing Service System offers the best possibility for fulfillment of rural health service goals within the current health man-power situation. In order to identify appropriate strategies to combat the present difficulties in Korean rural health services and to utilize nurses and other health personnel in community-centered health programs, a search was made for examples of innovative service models throughout the world. An extensive literature survey and field visits to project sites both in Korea and in the United States were made. Experts in the field of world health, health service, planners, administrators, and medical and nursing practitioners in Korea, in the United States as well as visitors from other Asian countries were widely consulted. On the basis of information and inputs from these experts a new rural health service model has been constructed within the conceptual framework of community development, especially of the innovation diffusion Model. It is considered especially important that citizens in each community develop capacities for self-care with assistance and supports from available health professionals and participate in health service-related decisions that affect their own well-being. The proposed model is based upon the regionalization of health care planning utilizing a comprehensive Nursing Service System at the immediate delivery level The model features: (1) a health administration unit at each administrative level; (2) mechanisms for community participation; (3) a continuous source of primary health care at the local community level; (4) relative centralization of specialty care and provision of tertiary or super-specialty care only at major national metropolitan centers; and (5) a system for patient referral to the appropriate level of care. This model has been built around professional nurses as the key community health workers because their training is particularly suited and because large numbers of well-trained nurses are currently available and being trained. The special element in this model is a professional nurse-guided, self-care facilitating primary care Community Nursing Service System. This is supported by a Nursing Extension Service as a new training and support structure. (See attached diagrams). A broad spectrum of programs was proposed for the Community Nursing Service System. These were designed to establish a balance of activities between the clinic-centered individual care component and the field activity-centered educational and supportive component of health care services. Examples of possible program alternatives and proposed guidelines for health care in specific situations were presented, as well as the roles and functions of the key health personnel within the Community Nursing Service System. This Rural Health Service Model was proposed as a real alternative to the maldistributed, inequitable, uncoordinated solo-practice, physician-centered fee-for-service health care available to Koreans today.

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A STUDY ON THE CHANGE OF SALIVARY FLUORIDE CONCENTRATION WITH TIME AFTER VARIOUS TOPICAL FLUORIDE TREATMENTS (각종 불소처치 이후 시간변화에 따른 타액내 불소농도 변화에 관한 연구)

  • Park, Soo-Jin;Kim, Hyung-Doo;Kim, Chong-Chul
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.2
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    • pp.262-274
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    • 1999
  • Several alternatives for increasing the fluoride concentration in the mouth, such as water fluoridation, ingestion of fluoride supplements, fluoride paste, fluoride mouthrinse, application of fluoride gel are available. There is an impressive body of evidence that the topically deliverd fluorides are clinically effective in inhibiting the progression of dental caries. Recent studies on the cariostatic action of fluoride have indicated the importance of fluoride in the fluid environment of the teeth. The fluoride levels in unstimulated whole saliva can be considered indicative of F in the aqueous phase available for interaction with the tooth surface at a given time. The retention of F in the mouth after topical fluoride treatment is considered to be an important factor in the clinical efficacy of F. The aim of this study was to determine the elevation and clearance of fluoride in whole saliv after the following topical flouride treatments using HMDS-diffusion technique and fluoride ion electrode. The obtained results were as follow: 1. Average salivary fluoride concentration in the unstimulated whole saliva was $0.0152ppm{\pm}0.0091ppm$. Unstimulated salivary flow rate was between 0.34-0.36ml/min and there was no statistically significant difference among the groups(p>0.05). 2. Except for the immediate time after treatment, fluoride levels followed as APF gel>neutral gel>F-rinse>F-paste. There was no statistical difference between the salivary F concentration of F-paste group and that of control group after 2 hours. In case of F-rinse group, after 3 hours the concentration had dropped to baseline value. But there was statistically significant difference among the F concentraion of F gel groups and that of control group(p<0.05). 3. The mean $AUC_{0-120min}$ values were followed as neutral gel>APF gel>F-rinse>F-paste, and the values of the two former groups were significantly higher than those of the two latter groups(p<0.05).

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A Study on the Indoor-Outdoor $NO_2$ Levels and Personal Exposures to $NO_2$ with Analysis of factors Affecting the $NO_2$ Concentrations - Centering on Urban Homes and Housewives - (실내외 $NO_2$농도 및 $NO_2$개인폭로량과 이들에 영향을 미치는 요인에 관한 연구 -도시지역 주택 및 주부를 대상으로-)

  • Chun, Jin-Ho;Lee, Chae-Un;Kim, Joon-Youn;Chung, Yo-Han
    • Journal of Preventive Medicine and Public Health
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    • v.21 no.1 s.23
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    • pp.132-151
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    • 1988
  • This study was conducted to establish the control program for preventing unfavorable health effects of nitrogen dioxide($NO_2$) exposure in homes by preparing the fundamental data for evaluation of relation-ships between $NO_2$ levels and influencing factors through measurements of indoor-outdoor $NO_2$ levels and personal $NO_2$ exposures for housewives with questionnaire survey on 172 homes in Pusan area from April to June, 1987 $NO_2$ measurements were made by using diffusion tube samplers(Palmes tube $NO_2$ sampler) for one week at 4 sites in homes ; kitchen(KIT), bedroom(BED), living room(LIV), outdoor(OUT) and near the collar of housewives(personal exposure livel, PNO). The details of questionnaire were number of household members(FAM), number of regular smokers (SMOKER), daily number of meals eaten(MEAL), type of housing units(HOUSE), location of house with distance from the heavy traffic roads as walking time(DIST), and of kitchen(KAREA), kind of cooking fuels(FUEL), cooking time of each meal(CTIME), usage of kitchen fan for cooking(FAN), type of heating facilities(HEAT) and so on of subject homes. The Obtained results were as fellows : 1) The mean $NO_2$ level was significantly higher at indoors than outdoors(p<0.01) and the kitchen $NO_2$ level was the highest with $33.7{\pm}13.6ppb$(9.5-81.5ppb). The mean personal exposure level of $NO_2$ for housewives was $20.6{\pm}8.8ppb$(3.1-46.9ppb). 2) The mean indoor $NO_2$ level was significantly higher in the group of household members above 5 than below 4(p<0.05), in detached dwellings than apartments(p<0.001), within 5 minutes of distance than over 5 minutes(p<0.001), in the group of unusing fan(p<0.001), in the group of longer cooking time(p<0.001), and it was in order of coal briquette, gas, electricity and oil by kind of cooking fuels(p<0.05). 3) Variables showing significant correlation(p<0.001) with indoor $NO_2$ level were kitchen $NO_2$ level(r=0.8677), cooking time(r=0.5921), outdoor $NO_2$ level(r=0.5192), personal $NO_2$ exposure level(r=0.4615), usage of kitchen fan(r=0.3573) and location of house(r=-0.2988) 4) As a result of multiple regression analysis, the most significant influencing variable to the kitchen $NO_2$ level was cooking time[KIT=$-0.378{\pm}11.772$(CTIME)+0.298(OUT)+3.102(FAN)], it was kitchen $NO_2$ level to the indoor $NO_2$ level[IND=6.996+0.458(KIT)+0.230(OUT)-1.127(KAREA)], and it was indoor $NO_2$ level to the personal $NO_2$ exposure level[PNO=15.562+0.729(IND)-4.542(DIST)-0.200(KIT)] 5) It was recognized that aritificial ventilation in the kitchen, suppression of unnecessary combustion and replacement of cooking fuel, as much as possible, were effective means for decreasing indoor $NO_2$ levels in homes.

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Causative Pathogens and Therapeutic Assessment of Cefprozil in Acute Otitis Media (급성 중이염의 원인 병원균과 Cefprozil 치료의 임상적 평가)

  • Kang, Jin-Han;Kim, Jong Hyun;Park, Yong-Soo;Choi, Young-Chul;Noh, Heil;Yang, Hoon Shik;Kim, Kyu Sung;Moon, Yeon Sook;Hong, Young Jin
    • Clinical and Experimental Pediatrics
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    • v.46 no.5
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    • pp.459-466
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    • 2003
  • Purpose : AOM is the most common bacterial URI in children. The bacteriology and antibiotic Tx of AOM in children has been studied in many countries. But, there is few study of causative pathogens and antibiotic Tx of AOM in our country. In this aspect, we performed prospective clinical study to confirm the causative pathogens and assess the clinical responses of cefprozil in AOM patients. Methods : Thirty three AOM patients enrolled in this study. Tympanocentesis for isolation of causative pathogens were performed before Tx of cefprozil. The study patients received cefprozil with dose of 15 mg/kg/bid.po/day for 10-12 days, and initially assessed the clinical response at 4-5 days after receiving cefprozil and finally at the end visit. In vitro susceptibility tests of cefprozil to isolated pathogens were done by disc diffusion method, and in vitro susceptibility tests of cefaclor and cefixime to isolated pathogens were simultaneously performed. Results : Bacterial pathogens[S. pneumoniae(10), H. influenzae(5), S. aureus(2), M. catarrhalis(1) and Group A stretococcus(1)] were isolated from 19 patients. Clinically, all patients had history of abrupt high fever except one. Tympanic perforation was dominant in pathogens isolated cases, and otalgia was significantly developed in non-pathogens isolated cases. The ages of pathogens isolated cases were usually below 2 years. Eighty four point nine percent of the patients including two cases with isolation of intermediate resistant S. pneumoniae were clinically improved. Antimicrobial in vitro activity to S. pneumoniae of cefprozil were superior than that of cefacor and cefixime. Conclusion : We confirm that bacteria has the causative role in about 60% cases, and S. pneumoniae is the most common pathogen. Clinically, there were some differences in symptoms, signs and ages between pathogens isolated and non-pathogens isolated cases. The clinical responses of cefprozil in our patients revealed similar outcomes to other countries. And we reconfirm that cefprozil may be clinically effective in cases of AOM due to intermediate resistant S. pneumoniae.

Release Characteristics of Fission Gases with Spent Fuel Burn-up during the Voloxidation and OREOX Processes (사용후핵연료의 연소도 변화에 따른 산화 및 OREOX 공정에서 핵분열기체 방출 특성)

  • Park, Geun-Il;Cho, Kwang-Hun;Lee, Jung-Won;Park, Jang-Jin;Yang, Myung-Seung;Song, Kee-Chan
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.1
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    • pp.39-52
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    • 2007
  • Quantitative analysis on release behavior of the $^{85}Kr\;and\;^{14}C$ fission gases from the spent fuel material during the voloxidation and OREOX process has been performed. This thermal treatment step in a remote fabrication process to fabricate the dry-processed fuel from spent fuel has been used to obtain a fine powder The fractional release percent of fission gases from spent fuel materials with burn-up ranges from 27,000 MWd/tU to 65,000 MWd/tU have been evaluated by comparing the measured data with these initial inventories calculated by ORIGEN code. The release characteristics of $^{85}Kr\;and\;^{14}C$ fission gases during the voloxidation process at $500^{\circ}C$ seem to be closely linked to the degree of conversion efficiency of $UO_2\;to\;U_3O_8$ powder, and it is thus interpreted that the release from grain-boundary would be dominated during this step. The high release fraction of the fission gas from an oxidized powder during the OREOX process would be due to increase both in the gas diffusion at a temperature of $500^{\circ}C$ in a reduction step and in U atom mobility by the reduction. Therefore, it is believed that the fission gases release inventories in the OREOX step come from the inter-grain and inter-grain on $UO_2$ matrix. It is shown that the release fraction of $^{85}Kr\;and\;^{14}C$ fission gases during the voloxidation step would be increased as fuel burn-up increases, ranging from 6 to 12%, and a residual fission gas would completely be removed during the OREOX step. It seems that more effective treatment conditions for a removal of volatile fission gas are of powder formation by the oxidation in advance than the reduction of spent fuel at the higher temperature.

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