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Safety of Nano-sized Bee Pollen in both In-vitro and In-vivo Models (생체 외 및 생체 내 실험조건에서 나노화 벌 화분의 안전성 규명)

  • Pyeon, Hae-In;So, Soojeong;Bak, Jia;Lee, Seunghyun;Lee, Seungmin;Suh, Hwa-Jin;Lim, Je-Oh;Kim, Jung-Woo;Kim, Sun Youn;Lee, Se Ra;Lee, Yong Hyun;Chung, Il Kyung;Choi, Yun-Sik
    • Journal of Life Science
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    • v.28 no.5
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    • pp.605-614
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    • 2018
  • Bee pollen has an outer wall which is resistant to both acidic and basic solutions and even the digestive enzymes in the gastrointestinal tract. Therefore, the oral bioavailability of bee pollen is only 10-15%. A previous study reported on wet-grinding technology which increased the extraction of active ingredients from bee pollen by 11 times. This study was designed to investigate the safety of wet-ground bee pollen. First, a single dose of wet-ground bee pollen was tested in both rats and beagle dogs at dosages of 5, 10, and 20 g/kg and 1.5, 3, and 6 g/kg, respectively. In rats, compound-colored stools were found in those administered 10 g/kg or more of wet-ground bee pollen. In beagle dogs, 6 g/kg of wet-ground bee pollen induced diarrhea in one male for four hours. However, no obvious clinical signs were found through the end of the experiment in rats and beagle dogs. In addition, no histological abnormality was found in all animals. The data indicates that a single dose of up to 20 g/kg of wet-ground bee pollen is safe. Next, the genetic toxicity of nano-sized bee pollen was tested. This study employed a bacterial reverse mutation test, a micronucleus assay, and a chromosomal aberration assay. In the micronucleus assay, there was no genetic toxicity up to the dosage of 2 g/kg. There was also no genetic toxicity in the bacterial reverse mutation test and chromosomal aberration assay. This data provides important information in developing nano-sized bee pollen into more advanced functional foods and herbal medicines.

Comparision of Preparation Methods for Water Soluble Vitamin Analysis in Foods by Reversed-Phase High Performance Liquid Chromatography (역상 고속 액체 크로마토그래피에 의한 식품 중 수용성 비타민 분석을 위한 전처리법의 비교)

  • Kim, Hyung-Soo;Jang, Duck-Kyu;Woo, Dong-Kyun;Woo, Kang-Lyung
    • Korean Journal of Food Science and Technology
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    • v.34 no.2
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    • pp.141-150
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    • 2002
  • Owing to a need for simple extraction and purification for analysis of water soluble vitamins in food samples by RP-HPLC with UV-detector, the methods of bromelain and protease hydrolysis and $C_{18}$ Sep-Pak solid phase extraction were employed. The recoveries of standard water soluble vitamins by the bromelain and protease hydrolysis and $C_{18}$ Sep-Pak solid phase extraction were significantly high compared to AOAC methods in most of vitamins. The contents of pyridoxal determined with protest in the pork was similar, but in the bromelain hydrolysis and AOAC method, was high compared to the results of reference. The niacinamide, thiamin and riboflavin determined with bromelain and protease hydrolysis showed similar values to the results of references. In the potato, pyridoxamine was detected in the AOAC method, which was not detected in the bromelain and protease hydrolysis methods. Pyridoxal contents in the protease hydrolysis and AOAC methods were very similar to the results of references. The recoveries of fortified standard vitamins in food samples were significantly high and accurate compared to those of AOAC methods. The extraction and purification with $C_{18}$ Sep-Pak solid extractor might be considered superior method for the determination of water soluble vitamins in food samples.

Improvement of L-Lysine Productivity by Using Cell Fusion and Immobilized System (세포융합과 고정화 시스템을 이용한 L-Lysine의 생산성 향상)

  • Ryu, Beung-Ho;Kim, Hye-Sung;Roh, Myung-Hoon;Park, Bob-Gyu;Chung, Jong-Soon;Bai, Ki-Chul
    • Korean Journal of Food Science and Technology
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    • v.21 no.1
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    • pp.154-163
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    • 1989
  • This studies were designed to improve the productivity of L-lysine by protoplast fusion and immobilized system of fusants using strains of Brevibacterium flavum ATCC 21528, Brevibacterium lactofermentum ATCC 21086 and Corynebacterium glutamicum 820. Mutants were isolated with concentration method of $300{\mu}g/ml$ penicillin-G after treatment of $250{\mu}g/ml$ N-methyl-N-nitro-N-nitrosoguanidine. B. flavum $37-2(Hos^-,\;Kan^r,\;AEC^r)$, B. lactofermentum $6-2(Ile^-,\;Val^-,\;Str^r,\;AEC^r)$ and C. glutamicum 57-5$(Met^-,\;Thr^-,\;Rif^r,\;AEC^r)$ were isolated from mutants. Protoplasts were induced by being incubated with $500{\mu}g/ml$ lysozyme of lysis solution for 6 hr and the ratio of protoplast formation and regeneration were ranging from 97-99% and 33-37%, respectively. Fusion frequencies of fusants of BBFL 21, BCFG 37 and BCLG 59 were shown in the range from $1.25{\times}10^{-6}\;to\;5.83{\times}10^{-7}$ under the optimum conditions. The fusant BBFL 21 showed the highest productivity of $411.1\;ng/ml{\cdot}hr$ L-lysine in the lysine productivity broth at $30^{\circ}C$ for 72hr. In the immobilization systems, fusant BBFL 21 was employed in various polymer matrices such as sodium alginate, polyacrylamide, agar and ${\alpha}-carrageena$. The immobilization of sodium alginate showed the highest productivity of $413\;ng/ml{\cdot}hr$ L-lysine in the batch system. Continuous fermentation of immobilization system by using tube fermentor was produced the highest productivity $416.7\;ng/ml{\cdot}hr $ L-lysine under optimum condition.

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A Study on Home Economics Teachers' Concern for Performance Assessment and Its Implementation (기술ㆍ가정과 교사의 수행평가에 대한 관심도, 실행수준, 실행실태 및 관련변수)

  • 정미정;채정현
    • Journal of Korean Home Economics Education Association
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    • v.16 no.1
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    • pp.79-91
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    • 2004
  • The purpose of this study was to examine how much secondary school home economics teachers paid attention to performance assessment, to what extent and in which way they carried it out and how much support was given to that. It's basically meant to help provide more systematic support for performance assessment. The instrument used in this study was an Interest-Based Reform Adoption Model developed by Hall. Hord and et. al. at Texas University Research & Development Center for Teacher Education. and the subjects in this study were home economics teachers from 95 secondary schools in Gyeonggi province. After a survey was conducted by mail. the responses from 157 teachers were chosen for analysis. For data handling. SPSS/WIN program was utilized, and statistical data on mean. standard deviation and percentage were obtained. In addition. t-test and ANOVA were employed. The major findings of this study were as follows: First. as for their type of interest in performance assessment. influential type(35.0%) was most common. followed by confident type (29.3%). indifferent type(20.4%) and task type(15.3%). Second, regarding their implementation. every teacher carried out performance assessment. The largest group of the teachers fulfilled it as part of routine daily schedule(60 teachers. 38.2%). which could be called the level 4. The second largest group tried to integrate performance assessment to education programs(53 teachers. 33.8%). which could be called the level 5. The third largest group implemented it without making careful preparations for that(26 teachers. 16.6%). which could be called the level 3. and the fourth largest group tried to reinvent it(11 teachers. 7.0%), which could be called the level 6. The fifth largest group was in the middle of researching it(5 teachers, 3.2%). which could be called the level 1. And the sixth largest group was in the course of making preparations for that(2 teachers. 1.3%) . which could be named the level 2. Third. concerning how much they found themselves to be supported about performance assessment. they eave three or less marks to that. which showed that they weren't supported sufficiently There was little gap among them in their concern for performance assessment and its implementation levels. and this fact suggested that there wasn't satisfactory backup for their performance assessment.

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Effect of prosthetic designs and alveolar bone conditions on stress distribution in fixed partial dentures with pier abutments (중간 지대치가 존재하는 고정성 국소의치에서 보철물 설계 및 치조골 상태가 응력분포에 미치는 영향)

  • Cho, Wook;Kim, Chang-Seop;Jeon, Young-Chan;Jeong, Chang-Mo
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.3
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    • pp.328-334
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    • 2009
  • Statement of problem: Pier abutments act as a Class I fulcrum lever system when the teeth are incorporated in a fixed partial denture with rigid connectors. Therefore non-rigid connector incorporated into the fixed partial denture might reduce the stresses created by the leverage. Purpose: The purpose of this study was to evaluate, by means of finite element method, the effects of non-rigid connectors and supporting alveolar bone level on stress distribution for fixed partial dentures with pier abutments. Material and methods: A 2-dimensional finite element model simulating a 5-unit metal ceramic fixed partial denture with a pier abutment with rigid or non-rigid designs, the connector was located at the distal region of the second premolar, was developed. In the model, the lower canine, second premolar, and second molar served as abutments. Four types of alveolar bone condition were employed. One was normal bone condition and others were supporting bone reduced 20% height at one abutment. Two different loading conditions, each 150 N on 1st premolar and 1st molar and 300N on 1st molar, were used. Results: Two types of FPD were displaced apically. The amount of displacement decreased in an almost linear slope away from the loaded point. Non-rigid design tended to cause the higher stresses in supporting bone of premolar and molar abutments and the lower stresses in that of canine than rigid design. Alveolar bone loss increased the stresses in supporting bone of corresponding abutment. Conclusion: Careful evaluation of the retentive capacity of retainers and the periodontal condition of abutments may be required for the prosthetic design of fixed partial denture with a pier abutment.

A STUDY ON WEAR RESISTANCE OF FLOWABLE COMPOSITE RESINS (유동성 복합레진의 마모저항성에 관한 연구)

  • Yun, Yeon-Hee;Kim, Jung-Wook;Lee, Sang-Hoon;Hahn, Se-Hyun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.29 no.2
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    • pp.217-225
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    • 2002
  • When we use the flowable resin on the primary molars for quick handling, one of the most important property is the wear resistance. This study was performed to compare the wear resistance characteristics of four flowable composite resins [Arabesk flow (group 1), Tetric flow (group 2), Aeliteflow (group 3), Filtek flow (group 4)] to that of one control composite resin [Z100 (group 5)]. Specimen discs(n=10), 10mm wide and 2mm thick, were stored in distilled water at $37^{\circ}C$ for 7 days prior to testing. The specimens were subjected to 50,000 strokes at 2 Hz on the MTS system. During the test, the following parameters were maintained: the lateral excursion at 0.4mm, occlusal force at 2-100N with a force profile in the form of a half sine wave. The measurements of volume loss, depth of wear, and Vicker's hardness number of composite resins, and SEM observations of the polished and abraded surfaces were established. One-way ANOVA and Scheffe's multiple comparison test were employed to detect statistically significant differences among the flowable composite resin groups and the control composite group at P<.05. The following results were obtained: 1. Group 3 showed the least volume loss, while group 4 showed the greatest. The mean volume loss increased in the following order: group 3

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An Analysis of the Relationship between Climacteric Symptoms and Management of Menopause in Middle-aged Women (일 지역 중년여성의 폐경증상과 폐경관리와의 관계에 대한 연구)

  • Song, Ae-Ri
    • The Journal of Korean Academic Society of Nursing Education
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    • v.7 no.2
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    • pp.308-322
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    • 2001
  • The purpose of this study was to investigate the relationship between climacteric symptoms and management of menopause of middle -aged women. The subjects of this study were 261 women(40 to 60 years old). Data were collected from Jun. 1 to Jul. 15, 2001 by a structured questionnaire. The instruments employed were : 1) The Climacteric Symptoms Scale developed by Aeri Song and Eun soon Chung(1998). 2) The Management of Menopause Scale developed by Aeri Song(1997). The data were analyzed by the SPSS p.c. program using t-test, ANOVA and Pearson correlation coefficient. The results of the study were as follows : 1. Mean score of climacteric symptoms was $2.18{\pm}0.39$(Maximum 4, Minimum 1). The mean scores among the categories of climacteric symptoms, in descending order, were : a) physical and physiological reactions ($2.62{\pm}0.53$), b) social and family relationships ($2.23{\pm}0.50$), c) psychiatric and psychological reactions ($2.08{\pm}0.49$), d) relationship with sexual partner($1.73{\pm}0.54$), e) genitourinary reactions ($1.72{\pm}0.55$). 2. Mean score of management of menopause was $1.79{\pm}0.45$ (Maximum 4, Minimum 1). The mean scores among the categories of management of menopause, in descending order, were : a) dietary management($2.57{\pm}0.52$), b) self control ($2.24{\pm}0.57$), c) management of exercise and physical activity($2.14{\pm}0.75$), d) management of sex life($1.71{\pm}0.47$), e) management of professional health maintenance($1.61{\pm}0.59$). 3. There were statistically significant differences in the score of middle-aged women's self reported climacteric symptoms according to : a) occupation (t=-2.79, p<0.001) b) marriage state (t=-2.29, p<0.05) c) age of menarche (F=4.66, p<0.001) d) method of Sanhujori (post natal care & treatment) (F=4.22, p<0.001) e) hormone replacement therapy (t=-3.09, p<0.05). From the above statistics, several significant findings were noted : a) There were more climacteric symptoms from those who were unemployed, those who had no partner or were divorced and those who started a menarche earlier. b) There were less climacteric symptoms reported from those on hormone replacement therapy and those who followed their parents or parents-in-law advice regarding Sanhujori (postnatal care) 4. There were statistically significant differences in the score of middle-aged women's self reported management of menopause according to : The educational background (F=7.63, p<0.001), religion (F=3.74, p<0.001), income (F=3.65, p<0.001), number of parity (F=4.87, p<0.001), method of Sanhujori(postnatal care) (F=5.73, p<0.001), period of Sanhujori (postnatal care) (F=2.81, p<0.05), hormone replacement therapy (t=3.81, p<0.001). Women with higher educational background, strong religion, higher income, large number of parity, managed their post natal care well, were on HRT, managed their menopause significantly better than the others who took part in the survey. 5. It will be noted from the above that women's degree of climacteric symptoms showed a negative correlation to the management of menopause(r=-0.2146, p<0.001). The findings shown above suggest the need to develop a variable management of menopause, in order to improve climacteric symptoms of middle-aged women. It is hoped that the above findings will stimulate more detailed research into this matter, and thereby enable guidance to be given to women going through the menopause to cope with it in a less stressful way.

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A Study on the Effect of Donors' Utility on Their Intention for Donation Continuity Focusing on Private Contribution to Social Welfare Organizations (사회복지기관 개인기부자들의 기부효용감이 기부지속의도에 미치는 영향 -기관신뢰감과 자기수용감의 매개효과와 경제수준의 조절효과를 중심으로-)

  • Lee, Wonjune
    • Korean Journal of Social Welfare
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    • v.66 no.1
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    • pp.333-361
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    • 2014
  • By viewing donors for social welfare organization as both givers and beneficiaries, this study aims to address the correlations between the continuity of donors' contributions and enhanced sense of satisfaction as a consequence of participating in donation activities. The predominant concern of this study centers on: (1) the direct effects of individuals' emotional utility, demonstrable utility, trust toward donee organization, self acceptance on the continuation of their donation; (2) the direct effects of individuals' emotional utility, demonstrable utility, trust toward donee organizations on individuals' self-acceptance; (3) the direct effects of individuals' emotional utility, demonstrable utility on their trust toward a donee organization; (4) the indirect effects of individuals' self acceptance on two paths i.e. emotional utility${\rightarrow}$trust${\rightarrow}$self acceptance, and demonstrable utility${\rightarrow}$trust${\rightarrow}$self acceptance; (5) the indirect effects of individuals' individuals' trust toward donee organization on self acceptance on four paths i.e. emotional utility${\rightarrow}$trust${\rightarrow}$continuity of donation; demonstrable utility${\rightarrow}$trust${\rightarrow}$continuity of donation; emotional utility${\rightarrow}$trust${\rightarrow}$self-acceptance, and demonstrable utility${\rightarrow}$trust${\rightarrow}$self-acceptance; (6) the moderating effects of 'financial status' on the causal relationships in the prescribed structural equation model(SEM). In order to verify the moderating effect of 'financial status', multi-group analysis between each of the two groups were conducted. Research is based on a survey among 1116 donors who had made charitable, monetary contributions to social welfare organizations in Daegu and Kyungpook province. Data was collected from 29 organizations. In order to address the research questions, structural equation were employed. A variety of tests are conducted(metric invariance, critical ratio for difference, structural invariance, multi-group analysis, bias-corrected boot-strapping, latent mean analysis including Cohen's effect test).

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Study on Factors Determining Labor Force Participation Rate of Older males : The Elderly Poverty Labor Hypothesis and Skill-Biased Technological Change Hypothesis (고령남성의 경제활동참가 결정요인 연구 - 노후빈곤노동가설 및 숙련편향기술진보설을 중심으로 -)

  • Ji, Eun-Jeong
    • Korean Journal of Social Welfare
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    • v.60 no.3
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    • pp.31-58
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    • 2008
  • This study examines applying the elderly poverty labor hypothesis and skill-biased technological change hypothesis to labor force participation rate(LFPR) of older males in Korea. These hypotheses have hardly been examined on the this group. The analysis is based on the data "Summary of economically active population($1965{\sim}2007$)", "Population projection($1965{\sim}2007$)", "Report on wage structure survey($1993{\sim}2005$)" and "Korea Labor and Income Panel Study($1998{\sim}2006$)". The method employed for this study is logistic regression. The main results from this analysis are summarized in five points. Firstly, Korean older males' LFPR have been increasing since 1965 when industrialization was expanding at full steam. This trend has been different from the decreasing trend of industrialized countries. The second finding is that poor older males' LFPR is, on the average, 5.2% higher than that of non-poor older males from 1998 to 2005. The third result is that the non-elderly man has been increasingly positioned at higher grade occupations, while the elderly man has been held at lower grade occupations. The fourth is that labor demand for highly educated workers has exceeded the increased labor supply of the group, while the demand for low educated workers has decreased far beyond the declined labor supply. As a result, college premium has increased from 139% in 1993 to 157.8% in 2005. The final main implication of this study is that the industrialization theory and modernization hypothesis still holds for the LFPR of Korean older males. However, the elderly affluence hypothesis of the LFPR of older males are hardly persuasive in explaining Korean phenomenon. Especially, we find that the elderly poverty is the main mechanism in determining the Korean LFPR in old ages. This supports the elderly poverty labor hypothesis presented in this study. Skill-biased technological change hypothesis partially explains the LFPR of older man. However, we believe that other factors; human capital specially high school education rather than university education and skill required in less skill biased occupations or the poverty; also have taken effect.

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Study on the Availability of Repeated Flexible Bronchoscopy(RFB) (반복적 굴곡성 기관지경검사(RFB)의 유용성에 대한 연구)

  • Lee, Hong-Lyeol;Moon, Tae-Hoon;Cho, Jae-Hwa;Ryu, Jeong-Seon;Kwak, Seung-Min;Cho, Chul-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.3
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    • pp.365-376
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    • 2000
  • Background : Ever since Flexible Fiberoptic Bronchoscopy was introduced into clinical practice, it has played an important role in both diagnosis and therapy of respiratory diseases. Repeated bronchoscopic examinations is are not so uncommon. This study was designed prospectively to assess the clinical availability of the Repeated Flexible Bronchoscopy (RFB). Methods : Pre-established indications were as follows : 1) To confirm diagnosis or the cell type in proven malignancy 2) to diagnose or locate hemoptysis 3) to follow-up or confirm recurrence 4) to use in therapy. We performed RFB and analyzed the data in 156 patients during 28-month period. Results : The frequency of RFB was 23.0%. The indication for diagnosis or cell type of malignancy was 25 cases, of which 2 cases were confirmed by a third bronchoscopic examination and 3 cases by surgical procedures. Localization of the bleeding site was confirmed in 53.8%. RFB for small cell lung cancer yielded more information on residual or recurred lesion not apparent even with the CT scan in 30%. Previous cases of bronchostenosis due to endo-bronchial tuberculosis was shown to have worsened in 66.7%. Therapeutic manipulations were done in 126 cases, and bronchial suction was most common. Complications showed decreasing tendency with repeated examinations. Conclusion : The RFB for diagnosis or cell type of malignancy was useful in that comfirmation of diagnosis was possible in 85.7% of malignancy. More aggressive procedures should be employed including TBLB or TBNA. The RFB showed possible usefulness in the follow-up of patients with small cell lung cancer. For the patients with hemoptysis or endobronchial tuberculosis, the RFB did not the significance did not show significance because its results did not influence the diagnosis, therapy or clinical course.

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