• 대한치과교정학회지
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• 제45권3호
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• pp.121-129
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• 2015

Objective: This study aimed to assess three-dimensional changes in the temporomandibular joint positions and mandibular dimensions after correction of dental factors restricting mandibular growth in patients with Class II division 1 or division 2 malocclusion in the pubertal growth period. Methods: This prospective clinical study included 14 patients each with Class II division 1 (group I) and Class II division 2 (group II) malocclusions. The quad-helix was used for maxillary expansion, while utility arches were used for intrusion (group I) or protrusion and intrusion (group II) of the maxillary incisors. After approximately 2 months of treatment, an adequate maxillary arch width and acceptable maxillary incisor inclination were obtained. The patients were followed for an average of 6 months. Intraoral and extraoral photographs, plaster models, and cone-beam computed tomography (CBCT) images were obtained before and after treatment. Lateral cephalometric and temporomandibular joint measurements were made from the CBCT images. Results: The mandibular dimensions increased in both groups, although mandibular positional changes were also found in group II. There were no differences in the condylar position within the mandibular fossa or the condylar dimensions. The mandibular fossa depth and condylar positions were symmetrical at treatment initiation and completion. Conclusions: Class II malocclusion can be partially corrected by achieving an ideal maxillary arch form, particularly in patients with Class II division 2 malocclusion. Restrictions of the mandible in the transverse or sagittal plane do not affect the temporomandibular joint positions in these patients because of the high adaptability of this joint.

• 대한한의학회지
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• 제31권2호
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• pp.48-63
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• 2010

Objectives: Yonnyuniksoogobon-dan (Yan Nian Yi Shou Gu Ben Dan 延年益壽固本丹) is composed of 11 herbs (Polygoni Mutiflori Radix, Lycii Radicis Cortex, Polia, Rehmanniae Radix, Rehmanniae Radix Preparat, Asparagi Radix, Liriopis Tuber, Lycii Fructus, Acori Graminei Rhizoma, Angelicae Acutiloba Radix, and Pini Folium) based on Yonryunggobon-dan (Yan Ling Gu Ben Dan 延齡固本丹) and Yonnyuniksoobulrho-dan (Yan Nian Yi Shou Bu Lao Dan 延年益壽不老丹). This study evaluated hair growth promoting effect of Yonnyuniksoogobon-dan on the shaved C57BL/6 mice. Methods: Yonnyuniksoogobon-dan was treated by oral administration (Sample I) and oral administration plus skin application (Sample II) once a day for 12 days. Hair regrowth was photographically and histologically determined during the experimental period. Hair growth cycle related factors (EGF, TGF-${\beta}1$) and vascular factors (VEGF, iNOS) were also determined with immunohistochemistry. Results: 1. On gross observation of hair regrowth, Sample I and Sample II groups demonstrated acceleration of hair regrowth. 2. The hair regrowth index of the Sample I group increased significantly from 7 days (P<0.05) to 12 days (P<0.01) after the shave while that of the Sample II group significantly increased at 12 days (P<0.05). 3. On histological observation, both Sample I and Sample II groups demonstrated histological improvement and increases of number and diameter of the hair follicles. 4. EGF expressions on the root sheath of hair follicles were up-regulated in both Sample I and Sample II groups. 5. TGF-${\beta}1$ expressions on the root sheath of hair follicles were not regulated in Sample I or Sample II groups. 6. VEGF expressions in the surrounding tissues of hair follicles were up-regulated in both Sample I and Sample II groups. 7. iNOS expressions in the surrounding tissues of hair follicles were down-regulated in both Sample I and Sample II groups. Conclusions: These results suggest that Yonnyuniksoogobon-dan has hair growth-promoting activity and these effects relate to up-regulations of EGF and VEFG expressions and down-regulations of TGF-${\beta}1$ and iNOS expressions on hair roots.

• Journal of Preventive Medicine and Public Health
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• 제38권1호
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• pp.45-52
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• 2005

Objectives : To investigate the fatigue subjective symptoms and VDT related risk factors in bank workers. Methods : A total of 2178 workers (62.8% male, 37.2% female) were surveyed with a self-administered and structured questionnaire consisting of 30 fatigue symptoms and other VDT related factors regarding work characteristics, work postures, work environments, personal medical histories, etc. Fatigue subjective symptoms were divided into 3 groups of 10 questions each: a dull, drowsy and exhausted feeling (Group I), a mental decline of working motivation (Group II), or a feeling of incongruity in the body and dysfunction of autonomic nervous system (Group III). Each question was weighted as 0 for 'none', 1 for 'sometimes', and 2 for 'always'. Results : Mean age was $35.8{\pm}7.2$ years ($38.9{\pm}6.0$ in males, $30.6{\pm}5.8$ in females), Mean work duration was $7.7{\pm}7.1$ years ($8.4{\pm}7.4$ in males, $6.5{\pm}6.4$ in females). Mean symptom score in males was $11.0{\pm}8.1$ ($4.9{\pm}3.1$ in Group I, $3.0{\pm}3.1$ in Group II, $3.1{\pm}2.8$ in Group III) and in females was $17.5{\pm}9.5$ ($7.0{\pm}3.8$ in Group I, $4.6{\pm}3.5$ in Group II, $5.9{\pm}3.4$ in Group III). Mean scores were higher in the order of Group I>III>II. Females had significantly higher scores than males in all three groups (p<0.001). Most common symptoms complained of as 'always' or 'sometimes' were feel strained in the eyes' (85.4%) among Group I, 'find difficulty in thinking'(54.2%) among Group II, and 'feel stiff in the shoulders (72.3%) among Group III. In multiple regression analysis, female, non-straight spine at workstation, more VDT work hours, history of physical therapy, glare of screen, overtime work, young age, and non-horizontal elbow position were significantly related with high score of symptoms. Conclusions : More supportive VDT work environment and education for correct work postures for VDT workers are recommended.

• 대한기계학회논문집
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• 제15권1호
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• pp.201-208
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• 1991

본 연구에서는 균일 열유동이 접합면에 수직으로 흐르고 접합 경계면 균열의 열경계조건이 단열되어 있는 경우에 균질 및 접합재료 모두에 적용될 수 있는 열응세 기계수를 복소해석방법을 이용하여 구하고자 한다.

• 한국의류학회지
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• 제19권5호
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• pp.699-712
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• 1995

The purpose of this study was 1) to identify the constructing factors of jeans brand image 2) to analyze the domestic jeans market using perceptual maps of three benefit segments based on stdy(I). The questionnaire consisted of brand preference, attribute of brand image and wearer image was selected from the previous studies or developed for this study. The subjects were 350 male and female university students who have purchased at least one of the nine jeans wear brand selected for the study. For statistical analysis, reliability test, factor analysis, MANOVA, and multiple regression were used. The results of this study were as follows: 1. Symbolism, quality, and economy were found out as constricting factors of brand image in the attribute dimensions, while innovative and active image were found out in the wearer image dimensions. 2. 9 Perceptual maps of attribute dimensions and 3 perceptual maps of wearer image dimensions were constructed and each ideal vector was drawn.

• The Korean Journal of Ecology
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• 제21권4호
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• pp.321-328
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• 1998

To describe the major environmental factors operating in coastal wetland and to characterize the distribution of the plant species over the wetland in relation to the major environmental gradients, 12 soil physical and chemical properties were determined. The gradient of water and osmotic potential of soil, electrical conductivity, sodium and chloride content and soil texture alsong the three habitat types of salt marshes, salt swamp and sand dune were occurred. The 24 coastal plant communities from principal component analysis (PCA) on the 12 variables were at designated as a gradient for soil texture and water potential related with salinity by Axis I and as a gradient for soil moisture and total nitrogen gradient by Axis II On Axis I were divided into 3 groups (1) 9 salt marsh communities including Salicornia herbacea communities (2) 5 salt swamp communities including Scirpus fluviatilis communities and (3) 10 sand dune communities including Jmperata cylindrica communities on Axis II were divided into 2 groups (1) salt marsh and sand dune communities, and (2) 3 salt swamp communities. The results could account for the zonation of plant communities on coastal wetland observed alsong envionmental gradients.

• Korean Chemical Engineering Research
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• 제59권2호
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• pp.219-224
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• 2021

Ion flotation is an efficient method to remove metal ions from aqueous solution. In this work, ion flotation was applied to calcium removal from aqueous solution. The parameters used included sodium stearate (SS) and sodium dodecyl sulfate (SDS) as collectors, 1-butanol and 1-propanol as frothers, pH, and air-flow rate. An L16 orthogonal array was chosen according to the mentioned factors and levels, and experimental tests were conducted according to the Taguchi orthogonal array. The results showed that all of the factors except one had significant effect on the flotation performance. The percentage contribution of parameters showed that type of frother and type of collector made the greatest (43.14%) and the lowest (9.86%) contribution, respectively. In optimal conditions, the recovery of Ca (II) ion was 45.67%. Also, the results illustrated that the Taguchi method could predict calcium removal from aqueous solution by ion flotation with 2.63%. This study showed that the use of ion flotation was an effective method for Ca (II) ion removal from aqueous solution.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1222-1227
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• 2003

Pitting wear is a dominant form of polyethylene surface damage in total knee replacements, and may originate from surface cracks that propagate under repeated tribological contact. In this study, stress intensity factors, $K_{I}$ and $K_{II}$, were calculated for a surface crack in a polyethylene - CoCr - bone system under the rolling and/or sliding contact pressures. Crack length and load location were considered in determination of probable crack propagation mechanisms and fracture modes. Positive $K_{I}$ values were obtained for shorter cracks in rolling contact and for all crack lengths when the sliding load was apart from the crack. $K_{II}$, was the greatest when the load was directly adjacent to the crack $(g/a={\pm}1)$. Sliding friction caused a substantial increase of both $K_{I}^{max}$ and $K_{II}^{max}$. The effective Mode I stress intensity factors, $K_{eff}$, were the greatest at $g/a={\pm}1$, showing the significance of high shear stresses generated by loads adjacent to surface cracks. Such behavior of $K_{eff}$ suggests mechanisms for surface pitting by which surface cracks may propagate along their original plane under repeated rolling or sliding contact.

• Asian-Australasian Journal of Animal Sciences
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• 제8권1호
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• pp.51-58
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• 1995

To examine whether colostral growth factors are transferred to the general circulation, concentrations of plasma cortisol, insulin, prolactin, growth hormone, insulin-like growth factors(IGFs) -I and -II, IGF-binding proteins(IGFBPs) and total protein were measured in newborn calves fed colostrums, milk of milk replacer before and after feeding at 12 h intervals during the first two days after birth. Plasma protein concentrations increased with time after than in milk- or milk replacer-fed calves. The mean protein concentration was greater in colostrum-fed than in milk- or milk replacer-fed calves. Plasma cortisol levels transiently declined after each feeding regardless of the type of diet, while insulin levels tended to increase. Mean concentrations of these hormones did not differ between dietary groups, nor did they change with time after birth. Plasma concentrations of prolactin and growth hormone did not differ between dietary groups and also did not change with time after birth or after feeding. Concentrations of IGF-I and IGF-II transiently increased at the second feeding period, but these, as well as plasma IGFBP profiles, were not different between groups or before and after feeding. Results did not indicate significant transfer of colostral growth factors across the newborn ruminant small intestine.

• 대한치과교정학회지
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• 제23권3호
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• pp.341-358
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• 1993

This study was investigated to evaluate the morphologic characteristics of deepbite tendency as multiple factors. The subjects consisted of 60 control subjects(male 25, female 35) and 137 deephite patients(68 male, 69 female). The deepbite group was composed of 4 subgroups(Class I 44, Class II div. 1 40, Class II div. 2 13, Class III 40). The mean age was 21.57 year for the control group 21 year for deepbite group lateral cephalograph in centric occlusion were taken, traced, and digitized for each subject. The statistically computerized analysis was carried out with SAS program. The results were as follows ; 1. In deepbite group, saddle angle is lesser than that of normal group. 2. The vertical dysplasia is prominent on anterior lower face and is closely related with mandibular form and inclination. 3. Without consideration of sagittal relationship, the dental factors such as curve of Spee, interincisal angle, U1 to upper lip length were prominent in the deepbite group. 4. Although there were individual variances in the perioral soft tissue profile, the lip presented more protruded pattern. 5. There was no significant difference in hyoid bone position and inclination between normal and deepbite group. 6. The multivariate discriminant analysis between normal and Class I deepbite group showed that curve of Spee, AB-MP angle, interincisal angle, articular agnle were critical in the determination of deepbite as multiple factors.