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Effect of Electrolyzed Water Combined with Ultrasound and Organic Acids to Reduce Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus on Perilla Leaves (유기산 및 초음파 병용처리된 전해수를 이용한 들깻잎 중 Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus의 저감효과)

  • Kim, Se-Ri;Oh, Ki-Won;Lee, Myoung-Hee;Jung, Chan-Sik;Lee, Seo-Hyun;Park, Sun-Ja;Park, Jung-Hyun;Ryu, Kyoung-Yul;Kim, Byung-Seok;Kim, Doo-Ho;Yun, Jong-Chul;Chung, Duck-Hwa
    • Journal of Food Hygiene and Safety
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    • v.27 no.3
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    • pp.264-270
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    • 2012
  • This study was performed to compared the effectiveness of individual treatments (electrolyzed water: EW, organic acid, and ultrasound) and their combination on reducing foodborne pathogens from perilla leaves. Perilla leaves were innoculated with a cocktail of Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus. Inoculated perilla leaves were treated with EW combined with different concentration of acetic acid (0.5%, 1.0%, 1.5%, 2.0%) for 1 min at room temperature. Treatment of 3 pathogens on perilla leaves with electrolyzed water combined with ultrasound (25 kHz) and 0.5% acetic acid was also performed for 1 min. While the numbers of S. Typhimurium and B. cereus showed reduced with increasing acetic acid concentration, there is no difference in the number of S. aureus treated with EW containing 0.5% to 1.5% acetic acid. Discoloration was observed the perilla leaves treated with EW combined with more than 1.0% acetic acid. For all three pathogens, the combined treatment of EW and ultrasound resulted in additional 0.42 to 0.72 $log_{10}$ CFU/g. The maxium reductions of S. Typhimurium and B. cereus were 0.95, 1.23 $log_{10}$ CFU/g after treatment with EW combined with 0.5% acetic acid and ultrasound simultaneously. The results suggest that the treatment of EW combined with 0.5% acetic acid and ultrasound increased pathogens reduction compared to individual treatment.

COMPARISON OF THE MARGINAL LEAKAGE OF SEVERAL FILLING MATERIALS ON CLASS V CAVITIES (제오급와동(第五級窩洞) 수복(修復)에 사용(使用)되는 수종(數種) 충전재(充塡材)의 변연누출(邊緣漏出) 비교(比較))

  • Kim, Mi-Ok;Cho, Kyew-Zeung
    • Restorative Dentistry and Endodontics
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    • v.14 no.2
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    • pp.20-29
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    • 1989
  • The purpose of the study is to evaluate the degree of the marginal leakage of class V cavities with 4 brands of esthetic filling materials by means of the dye penetration at the enamel & dentinal margins. 160 cavities of class V were prepared on the buccal & lingual surfaces of 80 extracted premolar teeth, which divided into 4 groups. The four groups of cavities were filled with Durafill$^{(R)}$-Durafill bond$^{(R)}$(KuIzer & Co GmbH), Bisfil M$^{(R)}$-Resin bond$^{(R)}$(BISCO Inc.), Silux$^{(R)}$-Scotchbond$^{(R)}$(3M Co.) and Fuji ionomer$^{(R)}$(type II, G-C Co.) each. All specimens were immersed in 2% methylene blue dye solution for 24 hours at $37^{\circ}C$ after a 30-second thermocycling at $4^{\circ}C$ and $60^{\circ}C$ and longitudinally sectioned with diamond disk into two parts. The results were as follows : 1. At enamel margins, the group filled with Durafill$^{(R)}$-Durafill bond$^{(R)}$, Bisfil M$^{(R)}$-Resin bond$^{(R)}$ and Silux$^{(R)}$-Scotchbond$^{(R)}$ show no significant difference each other(p>0.05), and the above groups show less marginal leakage comparing with the group filled with Fuji ionomer$^{(R)}$(p<0.01). 2. At dentinal margins, the group filled with Silux$^{(R)}$-Scotchbond$^{(R)}$ or Fuji ionomer$^{(R)}$ show less marginal leakage than that with Durafill$^{(R)}$-Durafill bond$^{(R)}$ or Bisfil M$^{(R)}$-Resin bond$^{(R)}$(p<0.01). 3. The enamel margins show less marginal leakage than dentinal margins in all the class V cavities(p<0.01).

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Shaping characteristics of two different motions nickel titanium file: a preliminary comparative study of surface profile and dentin chip (두 가지 다른 행정의 니켈 티타늄 파일의 성형 성상: 표면 성상, 상아질 삭편과 도말층에 대한 예비적 비교 연구)

  • Park, So-Ra;Park, Se-Hee;Cho, Kyung-Mo;Kim, Jin-Woo
    • Journal of Dental Rehabilitation and Applied Science
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    • v.30 no.2
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    • pp.121-130
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    • 2014
  • Purpose: To assess the surface profile of dentinal wall, dentin chips and smear layer during the canal shaping with rotary (ProTaper) and ProFile and reciprocating (WaveOne) nickel-titanium file. Materials and Methods: Sixty human extracted mandibular premolars and incisors with single canals were randomly selected. Three experimental groups (n = 20) were instrumented with ProTaper (F2), ProFile (25/.06), WaveOne (25/.08) with irrigation of 2.5% NaOCl. The dentin chips were collected from flute of file during each canal preparation. After canal preparation, roots were grinded and each group was divided into two subgroups (n = 10) for surface profile and smear layer of dentinal wall of shaped root canal. Each specimen was observed under scanning electron microscope for evaluating size of dentin chips, root canal surface recessions and smear layer. Scores of Smear layer were statistically analyzed using Kruskal Wallis test and Mann Whitney test at P = 0.05 level. Results: The size of dentin chips from ProFile, ProTaper and WaveOne was up to $7{\mu}m$, $6.5{\mu}m$, and$4{\mu}m$, respectively. In the surface profile, the width of surface irregularity was measured and Profile, ProTaper and WaveOne was up to $150{\mu}m$, $70{\mu}m$, and $80{\mu}m$, respectively. Completely cleaned root canals were not found. In the middle and apical third of the canals, WaveOne group showed higher smear layer score than ProFile and ProTaper groups (P < 0.05). Conclusion: Within limits of this study, reciprocating motion WaveOne group was not significant difference of shaping ability with the full-sequence ProFile and ProTaper systems except canal clearness of middle and apical third of root canal. When using WaveOne to shaping root canal, thorough root canal irrigation is recommended.

Comparison Study of the Pulmonary Function and Serum Carboxyhemoglobin Level Between the Traffic Policmen and Clerk Policemen (교통경찰과 비 교통경찰의 폐기능과 혈중 Carboxyhemoglobin 수치에 대한 비교연구)

  • Kim, Sung Min;Cheon, Gyu Rak;Kim, Young Wook;Kim, Joon Hyung;Lee, Ho Hak;Hong, Soon Chang;Lee, Seung Hee;Park, Sang Joon;Chung, Joon Oh;Kim, Yun Kwon;Kim, So Yon;Kim, Young Jung;Cho, Min Koo;Lee, Gwon Jun;Lee, Kyung In
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.6
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    • pp.560-569
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    • 2003
  • Background : A large number of pollutants such as sulfur dioxide, nitric oxide, carbon monoxide, particulate matter, and ozone influence on the body. These pollutants put a burden on the lung and the sequelae resulting from the oxidative stress are thought to contribute to the development of fibrotic lung disease, emphysema, chronic bronchitis and lung cancer. Also, carbon monoxide generated from the incomplete combustion of carbon-containing compounds is an important component of air pollution caused by traffic exhaust fumes and has the toxic effect of tissue hypoxia and produce various systemic and neurologic complications. The objective of this study is to compare the difference of pulmonary function and serum carboxyhemoglobin(CO-Hb) level between the traffic policemen and clerk policemen. Method : Three hundred and twenty-nine of traffic policemen, and one hundred and thirty clerk policemen were included between 2001 May and 2002 August. The policemen who took part in this study were asked to fill out a questionnaire which included questions on age, smoking, drinking, years of working, work-related symptoms and past medical history. The serum CO-Hb level was measured by using carboxyoximeter. Pulmonary function test was done by using automated spirometer. Additional tests, such as elecrocardiogram, urinalysis, chest radiography, blood chemistry, and CBC, were also done. Results : $FEV_1(%)$ was $97.1{\pm}0.85%$, and $105.7{\pm}1.21%$(p<0.05). FVC(%) was $94.6{\pm}0.67%$, and $102.1{\pm}1.09%$, respectively(p<0.05). Serum CO-Hb level was $2.4{\pm}0.06%$, and $1.8{\pm}0.08%$(p<0.05). After correction of confounding factors (age, smoking), significant variables were FVC(%), $FEV_1(%)$ and serum CO-Hb level(%)(p<0.05). Conclusion : Long exposure to air pollution may influence the pulmonary function and serum CO-Hb level. But, further prospective cohort study will be needed to elucidate detailed influences of specific pollutants on pulmonary function and serum carboxyhemoglobin level.

A Study on Preschool Teachers' Dental Health Recognition and Behaviors about Preschoolchildren Dental Health Care (어린이집 교사의 구강보건실태와 유아구강보건관리에 대한 인식)

  • Lee, Hyang-Nim;Shim, Hyung-Sun
    • Journal of dental hygiene science
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    • v.8 no.4
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    • pp.283-289
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    • 2008
  • This study was performed to obtain data about dental health to develop childrens' dental health education program. This research surved from from 22 July 2008 to 11 August 2008 and questionaire given to 140 teacher from Gwangsan-gu and Buk-gu and Dong-gu in Gwangju city. Collected data were analyzed with SPSS 12.0 program. The results of this study were as follows: 1. The dental health condition which teacher is recognizing is most with the facility 52.9% which is healthy, one day toothbrush qualitative number of times 3 times 67.1% and the dental floss qualitative number of times is 49.3%. Uses most the oral hygiene device which plentifully is 51.4% with the dental gargle solution, the dental problem which is knowing dental caries with 45.7% to be highest, perception dental sensitivity was 30.7%. 2. Periodical dental prosecuting says that 93.6% is executing, also the case which a dental inspection result in the parents notifies was 78.6%, after notifying treat, the case which confirms was 60.7%. The case which is the toothbrush qualitative time which is systematic was 95.0%, about dental healthily and food the case which executes an education was 93.6%. 3. About educational background by infantile dental health care of teacher with recognition currently the effectiveness of dental health care is higher from below junior college graduating (p < 0.05). dental hygienic relation experience event participation intention (p < 0.01) comes from the above of university graduation from infantile dental health care from important degree of teacher role was higher the junior college graduation group (p < 0.05). 4. Recognition there was not a difference which is beneficial with an educational background by about career by infantile dental health care of teacher. For the buccal cavity hygiene management of the infants thinks with the fact that also the development of the curricular material and the educational program and teacher buccal cavity hygiene education will be necessary.

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Initial nutritional status of stomach cancer patients (위암환자의 입원시 영양상태)

  • An, Su-Mi;Yun, Gi-Yeong;Kim, Eun-Sil;Gang, Won-Geun;Ryu, Dong-Won;Kim, Tae-Hyeon;Choe, Gyeong-Hyeon;Jeong, Eun-Ae;Im, Seon-Gye;Kim, Hong-Seon;Lee, Geum-Suk;Kim, Jong-Suk;Lee, Seon-Ok
    • Journal of the Korean Dietetic Association
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    • v.8 no.3
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    • pp.217-226
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    • 2002
  • The purpose of this study is to investigate initial nutritional status of stomach cancer patients. The study subjects were 88 patients with stomach cancer admitted at Kosin University Gospel Hospital in Busan. We assessed the initial nutritional status by anthropometric, biochemical and dietary intake data along with subjective global assessment(SGA). The results are as follows. 1. The mean age, weight, height, triceps skinfold thickness, mid arm circumference, and mid arm muscle circumference of the subjects were 55.9$\pm$11.0years, 60.0$\pm$9.8kg, 162.4$\pm$8.5cm, 10.9$\pm$5.7mm, 26.8$\pm$3.8cm, and 23.4$\pm$3.5cm respectively. The mean body mass index was within the normal range, with 22.7$\pm$2.8kg/m2, while 15.4% of the patients was underweight. The result shows that body fat mass and body protein mass of the patients with stomach cancer were decreased. 2. The mean biochemical data of the subjects were 4.0$\pm$0.5g/dl for albumin, 174.7$\pm$41.9mg/dl for cholesterol, 107.6$\pm$57.2mg/dl for triglyceride, 92.1μg/dl for Zn,  297.0$\pm$103.1mg/dl for transferrin, 1980.0$\pm$0.8$mm^3$ for total lymphocyte count. 3. Daily energy intake was 1997.8$\pm$579.3kcal. And the ratio of carbohydrate, protein, and lipid to energy intake was 72:14:14. 4. The patients were divided into three groups according to SGA performed by an observer. Group A(well nourished) was 55.7% with 49 patients, Group B(moderately malnourished) was 22.7 % with 20 patients, and Group C(severely malnourished) was 21.6 % with 19 patients. The three groups showed a significant difference in body weight(p<0.01), 1 month weight loss %(p<0.001), 6 months weight loss %(p<0.001), body mass index(p<0.01), and mid arm circumference(p<0.05), albumin(p<0.01), energy intake(p<0.05) as well as carbohydrate intake(p<0.05). From these results, it may be concluded that SGA can be used as a nutrition screening tool, and comprehensive nutrition assessment is desirable for those malnourished.

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Effects of Elevated $CO_2$ Concentration and Temperature on the Response of Seed Germination, Phenology and Leaf Morphology of Phytolacca insularis(Endemic species) and Phytolacca americana(Alien species) ($CO_2$농도와 온도증가에 따른 한국특산식물 섬자리공과 귀화식물 미국자리공의 발아, 식물계절 및 잎의 형태학적 반응연구)

  • Kim, Hae-Ran;You, Young-Han
    • Korean Journal of Environment and Ecology
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    • v.24 no.1
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    • pp.62-68
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    • 2010
  • This study was conducted to find out how the germination, phenology and leaf morphology of Phytolacca insularis(endemic species of Korea) and P. americana(alien species) react to the global warming situation. Seed and seedlings of two species were sampled and placed under two separate conditions for the experiment. One of the seed and seedlings was treated in the glass house with control(ambient $CO_2$+ambient temperature, (AC-AT), and the other with control(elevated $CO_2$+ elevated temperature, EC-ET), over the period of one year, 2008-2009. The germination rate of two species was fast, and the time of their germination started early, when they were treated at EC-ET than at AC-AT. Furthermore, the germination rate of Phytolacca insularis(endemic species of Korea) was found to be comparatively lower than that of P. americana(alien species). The former showed only vegetative growth whereas the latter showed both vegetative growth and reproductive growth in one year period. The more $CO_2$ degree and temperature increased, phenological responses of two species, including leaf growth, the formation of flower stems, flowering, and fruit maturing, became much faster, and the time of their leaf-yellowing was delayed. The lamina length of P. insularis was not significantly affected by elevated $CO_2$ and temperature. The lamina length of P. americana, on the other hand, became longer at EC-ET than at AC-AT, but the leaf width of both species increased at EC-ET. As for the number of leaves, both species showed no difference. Finally, the ratio of the leaf area of P. insularis was high at AC-AT, but P. americana was high at EC-ET. These results indicate that P. americana, aliens species, reacts more sensitively to global warming than P. insularis, endemic species, does.

'Jangseong Pyunbaek Healing Forest(JPHF)' Visitors: Socio-demographic Characteristics, Use Patterns and Motivational Factors by Types of Visitors ('장성 편백치유의 숲' 방문객 유형에 따른 인구사회학적 특성, 이용행태 및 방문동기 요인)

  • Kim, Sang-Oh;Kim, Sang-Mi
    • Korean Journal of Environment and Ecology
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    • v.32 no.2
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    • pp.203-214
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    • 2018
  • This study was conducted to investigate the types, socio-demographic characteristics, use patterns, and visit motivations of visitors to "Jangseong Pyunbaek Healing Forest (JPHF)." Data were collected from 216 samples selected by convenient sampling method using questionnaire survey between October and November 2016. Data obtained from 476 respondents of the same type of survey during the same period were partly used to examine the types of activities of visitors to the study site. The results showed that 77.0 percent of respondents were categorized as "visitor for recreation" (VR: Those who visit JPHF for the purpose of general recreational experiences such as appreciating landscapes, tourism, social interactions rather than better health or healing). On the other hand, only 10.3 percent of respondents were "visitor for healing" (VH: Those who visit JPHF for the purpose of better health or physical and mental healing). VH showed a higher level of visit experiences to JPHF than VR and tended to expect JPHF as "the place to enjoy calm and natural experiences" more than VR did. VH tended to visit JPHF "alone" more, and their group size was also smaller than VR. About 26.8 percent of all respondents were not aware that JPHF was the "healing forest," and VH showed higher awareness of it than VR. About 66.8% of respondents assessed the managerial and operating states of JPHF positively while only 6.2% assessed them negatively. There was no difference in the assessment of managerial and operating states between VR and VH. The visitors of JPHF showed the markedly high use in main forest roads (use rate: 47.4%) and "Healing Field" (use rate: 59.2%) of JPHF. Regarding the visit motivations to JPHF, VH showed higher importance on "quietude," "health," and "tension release" than VR while VR rated higher importance on "social interaction." The paper discussed the managerial implications, findings, limitations and further studies.

A Survey of the Basic Protection Manners of Dental Personnels Against Hepatitis B in and around Seoul (수도권 치과의료 종사자들의 B형 간염에 대한 기초방호실태 및 수행에 관한 조사)

  • Yoon, Mi-Sook;Park, Mi-Young
    • Journal of dental hygiene science
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    • v.1 no.1
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    • pp.46-52
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    • 2001
  • The purpose of this study was to examine dental personnels' concern for health, their personal protection manner, and whether or not they were inoculated against hepatitis B and made an inquiry of patients about that. It's ultimately meant to serve as a basis for the preparation of an anti-infection guide for the protection of dental personnels against all sorts of infectious diseases. After a survey was conducted from March 29 through May 9, 2001, the following findings were obtained: (1) The dental personnel group that had worked for 5 to less than 7 years took health examination the most, with 71.4%, before joining the hospital, and 61.5% of those who had served for 9 years or more, the greatest percentage, took medical checkup after joining the hospital(P<0.05). (2) The largest percentage of being inoculated against the anti-B type hepatitis after employment was 71.4% of the dental personnels over 35, and 57.7% of those with 9-year or more working experiences. Therefore, their age and service term made a significant difference(P<0.05). (3) There was no significant gap in personal protection practices between the dental hygienists and nurse aids(P>0.05). But the use of safety goggles for treatment was not properly done, with just 1.48 on the basis of 3 points, whereas the use of mask was scored 2.40 and the use of gloves was scored 1.96. (4) After a narcotic was used once, the leftovers were wasted by 89.7% of the dental hygienists and 70.0% of the nurse aids. More dental hygienists wasted them(P<0.05). (5) For hand washing, antibiotic liquid soap was used by 19.3% of the dental hygienists and 10.0% of the nurse aids, which were both very low percentage. And just 37.2% of the dental hygienists utilized a disposable paper towel to dry their hands, and only 36.0% of the nurse aids used the same(P<0.05).

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Extraction Characteristics of Saponin and Acidic Polysaccharide Based on the Red Ginseng Particle Size (홍삼의 입자크기에 따른 사포닌 및 산성다당체의 추출 특성)

  • Cho, Chang-Won;Kim, Sang-Wook;Rho, Jeong-Hae;Rhee, Young-Kyung;Kim, Kyung-Tack
    • Journal of Ginseng Research
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    • v.32 no.3
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    • pp.179-186
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    • 2008
  • Effect of pulverization on total solid, crude saponin, and acidic polysaccharide contents of dried red ginseng main root were tested. Several particle size samples, including red ginseng main root (non pulverized), $10{\sim}40$ mesh powder, $40{\sim}100$ mesh powder, and >100 mesh powder were used in the extraction. The sequential solvent extraction method (1st: 70% EtOH at $70^{\circ}C$ for 12 hr, 2nd: 70% EtOH at $70^{\circ}C$ for 12 hr, 3rd: water at $70^{\circ}C$ for 12 hr) was applied to extract the saponins and acidic polysaccharide. Extraction yield of total solid of pulverized red ginseng ($10{\sim}40$ mesh size) was increased to 20% compared with that of non-pulverized. Especially, the crude saponin content of pulverized red ginseng ($10{\sim}40$ mesh size) showed an increase of 47% over non-pulverized. No difference in the component ratio was observed by pulverization, when the individual ginsenosides were quantified by HPLC. Also, extraction yield of acidic polysaccharide of pulverized red ginseng ($10{\sim}40$ mesh size) was increased 57% compared with that of non-pulverized. The results suggested that pulverization might be useful for increasing the extraction yield of red ginseng components.