• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.100-105
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• 2015

The calculation method of infiltration loss in greenhouse has different ideas in each design standard, so there is a big difference in each method according to the size of greenhouses, it is necessary to establish a more accurate method that can be applied to the domestic. In order to provide basic data for the formulation of the calculation method of greenhouse heating load, we measured the infiltration rates using the tracer gas method in plastic greenhouses equipped with various thermal curtains. And then the calculation methods of infiltration loss in greenhouses were reviewed. Infiltration rates of the multi-span and single-span greenhouses were measured in the range of $0.042{\sim}0.245h^{-1}$ and $0.056{\sim}0.336h^{-1}$ respectively, single-span greenhouses appeared to be slightly larger. Infiltration rate of the greenhouse has been shown to significantly decrease depending on the number of thermal curtain layers without separation of single-span and multi-span. As the temperature differences between indoor and outdoor increase, the infiltration rates tended to increase. In the range of low wind speed during the experiments, changes of infiltration rate according to the outdoor wind speed could not find a consistent trend. Infiltration rates for the greenhouse heating design need to present the values at the appropriate temperature difference between indoor and outdoor. The change in the infiltration rate according to the wind speed does not need to be considered because the maximum heating load is calculated at a low wind speed range. However the correction factors to increase slightly the maximum heating load including the overall heat transfer coefficient should be applied at the strong wind regions. After reviewing the calculation method of infiltration loss, a method of using the infiltration heat transfer coefficient and the greenhouse covering area was found to have a problem, a method of using the infiltration rate and the greenhouse volume was determined to be reasonable.

• Journal of Periodontal and Implant Science
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• v.27 no.3
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• pp.533-547
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• 1997

In periodontics, much progress was made in the understanding of periodontal disease from 1960s to 1980s and in prevention and management of periodontal disease since the end of 1980s. This presentation will discuss about the prevalence of periodontal disease, treatment need, and provision of periodontal treatment in Korea, and how we could manage the periodontal disease efficiently in the future. According to an epidemiological study in Korea, periodontal disease(including gingivitis) was present in 82% of general population and periodontitis in 30-40% in adult population over 30y and juvenile periodontitis in 0.1% of adolescents. If we consider that at least 17% of these patients may have recurrent or refractory forms, there is obviously an abundance of disease that needs treatment, As a result of increase in life expectancy, senile population over 65 y will be increased from 6% in 1996 to 6.9% in 2000, and tooth retention rate and periodontal treatment need are expected to increase. Periodontists need all the help they can get from the general dentists to control periodontal disease. As for provision, postgraduate course in periodontics started in 1957 in Korea and produced over 700 specialized dentists in periodontics. One report indicated that the periodontists as well as general practitioners did periodontal therapy on only a few periodontal patients, because of specific control by current medical insurance system in Korea. Comprehensive periodontal examination is rarely done in local dental clinic. Therefore, enhancement of periodontal care in medical insurance system and education of simplified periodontal examination such as Periodontal Screening & Recording will make dentists diagnose and manage the management of adult patients is based on the recognition that there are multiple diseases, including gingivitis, chronic adlt periodontitis, and other more aggressive forms of periodontitis, and requires the earliest possible recognition of these three disease categories. In this presentation, we discuss practical approach using PSR to diagnose, manage and refer the patients, to facilitate the separation of the simple from the complex and the predictable from the unpredictable form of periodontal diseases and to integrate diagnostic and therapeutic techniques into private practice today.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.2
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• pp.125-140
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• 2011

The remnant of temporary cement on the intaglio surface of cast restoration may have a negative effect on the retentive strength of permanent cement. This study was to evaluate the effect of temporary cement cleaning methods on the retentive strength of cementation type implant prostheses. Prefabricated implant abutments - height 5.5mm, diameter 4.5mm, 6 degree axial wall taper with chamfer margins were used. Forty copings-abutment specimens were divided into four groups(each n=10) according to the cleaning methods for temporary cement(Temp-$Bond^{(R)}$) as follows : no temporary cementation(the control group), orange solvent, ultrasonic cleaning, air borne-particle abrasion. After the application of temporary cement and the separation, the cleaning procedure was performed according to the protocol of each group. The specimens were cemented with $Premier^{(R)}$ Implant $Cement^{TM}$. After the permanent cementation, the specimens were subjected to thermocycling and pulled out from the specimens with a universal testing machine at a cross-head speed of 0.5mm/min. After the retentive strength test, all the specimens were cleaned using ultrasonic cleaning, abraded with air borne-particles, and steam-cleaned. Likewise, the specimens were temporarily cemented(Temp-$Bond^{(R)}$ NE), cleaned according to the protocol of each group, cemented with $Premier^{(R)}$ Implant $Cement^{TM}$ and subjected to thermocycling and measurement of their retentive strength. The mean of group with orange solvent were significantly lower than those of other groups(p<0.05). There was no significance between group with ultrasonic cleaning and group with air borne-particle abrasion. Group with ultrasonic cleaning and group with air-particle abrasion were no significance at control group. There was no significance between group cemented with Temp-$Bond^{(R)}$ and group cemented with Temp-$Bond^{(R)}$ NE. Within the limitation of this study, it can be concluded that the temporary cement cleaning method with only orange solvent may have a negative effect on the retentive strength of permanent cement. Ultrasonic cleaning and air borne-particle abrasion methods are recommended for the temporary cement cleaning method on cementation type implant prostheses.

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.531-536
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• 2013

We developed a simple, sensitive, and specific analytical method for prometryn using gas chromatography-mass spectrometry (GC-MS). Prometryn is a selective herbicide used for the control of annual grasses and broadleaf weeds in cotton and celery crops. On the basis of high specificity, sensitivity, and reproducibility, combined with simple analytical operation, we propose that our newly developed method is suitable for use as a Ministry of Food and Drug Safety (MFDS, Korea) official method in the routine analysis of individual pesticide residues. Further, the method is applicable in clams. The separation condition for GC-MS was optimized by using a DB-5MS capillary column ($30m{\times}0.25mm$, 0.25 ${\mu}m$) with helium as the carrier gas, at a flow rate of 0.9 mL/min. We achieved high linearity over the concentration range 0.02-0.5 mg/L (correlation coefficient, $r^2$ >0.998). Our method is specific and sensitive, and has a quantitation limit of 0.04 mg/kg. The average recovery in clams ranged from 84.0% to 98.0%. The reproducibility of measurements expressed as the coefficient of variation (CV%) ranged from 3.0% to 7.1%. Our analytical procedure showed high accuracy and acceptable sensitivity regarding the analytical requirements for prometryn in fishery products. Finally, we successfully applied our method to the determination of residue levels in fishery products, and showed that none of the analyzed samples contained detectable amounts of residues.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.2
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• pp.141-149
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• 2017

To examine the cause of acute diarrheal disease in children and adolescents, 521 fecal samples underwent multiple-PCR for a period of two years, between March 2015 and February 20178, in the Jeju region of Korea. Based on the analysis of 179 positive samples, 102 samples were male (56.98%) and 77 were female (43.02%), and highest positive rates were shown in the age group of 3~4 years (51.96%) and 5~6 years (12.29%). When 209 cases (40.12%), including double infection were analyzed, there were 88 cases (16.89%) of norovirus-GII infection, 26 cases (4.99%) of Campylobacter spp. infection, 18 cases (3.45%) of rotavirus infection, 18 cases (3.45%) of Clostridium difficile Toxin B infection, 17 cases (3.26%) of adenovirus infection, 16 cases (3.07%) of Clostridium perfringens infection, 11 cases (2.11%) of astrovirus infection, 5 cases (0.96%) of Salmonella spp. infection, 3 cases (0.58%) of norovirus-GI, Yersinia spp. and Aeromonas spp. infections, and 1 case (0.19%) of verocytotoxin-producing E. coli infection. Based on a seasonal separation of early childhood, norovirus-GI and norovirus-GII mainly prevailed during the winter, when the temperature is low. Typical enteritis with an increased prevalence of rotavirus during the spring. Astrovirus prevailed between the months of April and October, when norovirus-GI, norovirus-GII, and rotavirus did not prevail. With increasing age, acute diarrheal disease was not only induced by a virus, but also by bacteria. Although a test for virus is an effective method when trying to identify the cause during early childhood by multiplex-PCR, it would be desirable to undergo tests for both virus and bacteria concurrently as age increases.

• Journal of Sericultural and Entomological Science
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• v.25 no.1
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• pp.1-20
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• 1983

It has been known that the insect molting hormone and its analogues exist also in plant kingdom and their concentration has been found to be about 0.1~2.0% of dry matter, which is equivalent to $10^3{\sim}10^5$ times of those in insects. This study was carried out; 1) to isolate the phytoecdysones from Korean Achyranthes radix and characterize their physico-chemical properties. 2) to investigate the biological activity of this phytoecdysone on Bombyx mori larvae. The resuls were summarized as follows; 1. The extraction method of phytoecdysones was optimized by three consecutive reflux for 1hr using 200g of dried and milled radix per 1l methanol. 2. The purification from the crude extract was made by a series of steps such as precipitation of gum-type polymer with n-Butyl acetate, adsorption on technical grade silica and chromatography with neutral alumina. The conditions of each step were optimized and the resulting crude crystal was about 500mg per kg dry radix. 3. The crude crystal from the cultivated Achyranthes(Achyranthes japonia) contained ecdysterone (20-hydroxyecdysone) and inokosterone in the proportion of one to one. In order to separate these, a series of processes such as acetylation, separation by alumina column chromatography deacetylation by alcoholysis, deionization and crystallization were introduced and optimized 125mg of ecdysterone and 18mg of inokosterone per kg dry radix were thus obtained. 4. The wild Achyranthes (Achyranthes obtusifolia) radix was found to contain the ecdysterone only. A 285mg of ecdysterone was crystallized per kg dry radix. 5. Isolated ecdysterone, inodosterone and acetylated compounds were characterized by IR., UV., NMR spectroscopy, mp, TLC and densitometry. 6. Ligation experiment was undertaken to confirm the biological activity of the purified ecdysterone; the ecdysterone could induce larval-pupal metamorphosis in the ligated abdomen of 4th instar larvae injecting 0.5~1.0${\mu}g$. 7. By ecdysterone feeding experiment using artificial diet, it was elucidated that the critical time of feeding would be the first half of each instar resulting in increased weight of silk layer. 8. The ecdysterone was fed to 5th instar silkworm at the level of 1, 2, 3, 5ppm of dry feed of artificial diet containing 5% mulberry leaves for 72hrs. At 2ppm of the concentration. body weight and silk layer weight were arrived at maximum. But at higher concentrations body weight and silk layer weight decreased than the control group. At 2ppm of the concentration, body weight was increased by 12.5%. 9. Feeding 2ppm of ecdysterone at the later half of 5th instar, the duration of larvae was shortened.

• Journal of Society of Preventive Korean Medicine
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• v.6 no.1
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• pp.51-95
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• 2002

1. As a point at issue of occidental medicine examination, followings have been indicated, 1) Occidental medical examination is performed by mainly test and instrument and therefore, role of doctors could be excluded and it could be diagnosed only for target disease and 2) in Korea, it could not be conducted in public medical system and therefore improvement effect of public health promotion could not be made due to increase of total medical expenses and infirmity of post management. These points are substantial limit of paradigm resided in occidental medicine and also problem caused by unique characteristics of medical system of Korea. In Korea, result of occidental medical examination show increased health risk from aged thirties and major diagnosed diseases are circulatory disease or chronic disease such as hepatic, hyperlipemic, hypertensional disease and diabetes, etc. Accounting that those chronic disease make a role as major public health risk, it is difficult that medical examination by only occidental medicine make effect on public health promotion. 2. Characteristics of oriental medicine examination could be summarized as diagnosis (information acquisition based on the facts) and demonstration (speculation based on acquired information) and in addition, quadruple diagnosis, as a medical examination method, include test as well as basic examination. Accounting on oriental medical examination, principally it is performed by independent herbalist and therefore, herbalist could acquire systemic result during first medical examination. Based on the theory of inner-outer examination, oriental medical examination has a principle of universe theory, systemic analysis of quadruple diagnosis, demonstration & reasoning. In addition, root of oriental medical examination could be found in pre-disease theory, a principal theory of oriental medicine. Pre-disease service could prove the advantage of oriental medicine in medical examination activities and therefore, it is needed that content of oriental medical examination should be actualized in current medical system. 3. In this study, oriental medical examination program, comprised of pulse-diagnosis, contrast muscular taking and medical consultation of herbalist is progressed communally with occidental medical examination. As pre-examination, questionary was given of general characteristics, health promoting life style, physical constitution and subjective symptom of musculoskeletal system. In addition, post-examination notification was given to subjects about health promoting control, physical constitution regimen and management of musculoskeletal system. During this study program, verification was conducted for input of acquired information and difference of each information after analysis and in addition, performed was analysis of factor influencing health promoting life style and musculoskeletal subjective symptom and evaluation of relationship of physical constitution and health promoting life study. In addition, it was verified of difference between musculoskeletal subjective symptom and result of muscle contrast picture evaluation. 4. Evaluation of oriental medical examination model is divided into 2 categories of oriental medical examination-consultation and result evaluation -post management. Oriental medical examination-consultation demands establishment of examination system, standardization of examination and establishment of examination form and in addition, it should be admitted as enlarged examination assists systemic quadruple diagnosis of herbalist not a key of oriental medical examination. In addition, information acquisition for research purpose should be performed according to the systemic research plan based on the separation of questionary for examination purpose and research purpose. For evaluation of the result, it was concluded that needed are result evaluation meets oriental medical system and post-notification system, informing health management information, based on examination result. 5. Accounting on satisfaction for oriental medical examination model, affirmative reply was much higher (66%) than negative (8.64%). Satisfaction of each area was in order of consultation of herbalist, systemic muscle contrast taking, pulse examination, post-notification and questionary fill-up and dissatisfaction was in order of post-notification, questionary fill-up, consultation of herbalist, systemic muscle contrast taking and pulse measurement. Satisfaction for collaborative examination of occidental and oriental medicine was over 60% and over 75% hope oriental examination would be included in later medical examination program. Based on this result, collaborative examination including occidental and oriental medicine could increase satisfaction of subjects for medical examination program.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.4
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• pp.263-267
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• 2007

Parabens are used in nearly all types of cosmetics and toiletries because they are formulated well and have broad spectrum of activity, interness, low costs and excellent chemical stability in relation to pH. 2-phenoxyethanol and chlorphenesin are common preservatives which are usually used in combination with parabens in cosmetics. Toxicity of parabens is generally low but application of parabens to damaged or broken skin has resulted in sensitization. Moreover, the possibility of their estrogenic potential, anesthetic effects and reproductive toxicity has been reported. Consequently there are some regulations in use of parabens. And the maximum permitted concentrations of chlorphenesin and 2-phenoxyethanol in cosmetic products are authorized by the same reasons. So it is important to control and estimate the amount of parabens in products. In this article, we proposed a valid method for the simultaneous determination of 8 preservatives including parabens in a short time using ultra performance liquid $chromatography^{TM}\;(UPLC^{TM})$. Separation of eight components was achieved in less than 10 min and resolutions were reasonable (USP resolution ${\geqq}\;2$). And limit of detection and quantification were evaluated. The method was suitably validated for specificity, linearity, precision (repeatability, intermediate precision) and accuracy for assay (recovery) based on International conference on harmonisation (ICH) guideline. The method was applicable to analysis of preservatives in cosmetic products.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.560-567
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• 1997

A new approach to obtain stable $W_1/O/W_2$ multiple emulsions has been studied ; The basis of the interfacial interaction between a PCL-PEO-PCL triblock copolymer and a lipophilic emulsifier in the dispersed oil phase was examined. $W_1/O/W_2$ multiple emulsions were prepared by the two-step method. Arlacel P-l35 was used as a liphophilic emulsifier and Synperonic PE/F 127 as a hydrophilic one. Eutanol-G was used as an oil phase. NaCl was encapsulated within the multiple emulsion droplets as the internal marker and its release rate studies were carried out. The suability of the multiple emulsions have been assessed by measuring Separation Ratios(%) and microscopic observations. The release of NaCl was significantly reduced in $W_1/O/W_2$ multiple emulsions containing PCL-PEO-PCL triblock copolymer(2k-4k-2k or 6k-4k-6k) in the oil phase. It may be concluded that the copolymer and the emulsifier form effective interfacial complex to enhance stability and to control the release rate. The effective diffusion coefficients of the NaCl were estimated as $2.64{\times}10^{-15}s$and $3.23{\times}10^{-16}gcm^2/s$ for the $W_1/O/W_2$ multiple emulsion containing 1.2 wt % of PCL-PEO-PCL triblock copolymers with compositions of 2k-4k-2k and 6k-4k-2k, respectively. The rate of release decreased with the increase of the initial concentration of NaCl. The results were examined in view of Higuchi mechanism. A kinetic model which is similar to the model for release of dispersed drugs from a polymeric matrix was found to be suitable for the release of NaCl from $W_1/O/W_2$ multiple emulsions.

• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.81-96
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• 2018

In this study, physicochemical properties of the natural jadeite powder were investigated and also the wash-off pack and liquid foundation containing the jadeite powder were prepared. In addition, each of these formulations was evaluated by various functional effects, sensory evaluation, stability and skin safety. In the wash-off pack, the far-infrared ray emissivity and radiation energy values increased as a function of the jadeite powder content. At a 3% jadeite powder content, the skin temperature increased by about $0.5^{\circ}C$ when the jadeite powder-containing formulation was applied to the skin. Besides, the chroma of the liquid foundation containing the jadeite powder more clearly expressed the original color of the skin. Moisture content measurements of the wash-off pack and liquid foundation containing the jadeite powder showed the highest moisture uptake of 5.0% and 63.0%, respectively. In sensorial test, the wash-off pack formulations containing the jadeite powder demonstrated improved affinities toward a skin, adherency, and moistness and combatted itching. The liquid foundation containing jadeite powder showed also improved affinities except for the coverage when compared to control formulations. Furthermore, the stability evaluation for 8 weeks revealed neither discoloration nor separation phenomenon for the formulations containing the jadeite powder. Moreover, the pH was found to be stable up to 8 weeks and the viscosity up to 4 weeks. Skin safety assessments showed that all formulations containing the jadeite powder were non-irritating. These results suggest that the jadeite powder as an inorganic pigment may serve as a new multi-functional cosmetic ingredient with stability and safety.