• The korean journal of orthodontics
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• v.31 no.1 s.84
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• pp.1-13
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• 2001

The extraction lot orthodontic treatment can be adopted for aligning crowded dentition, improving facial esthetics and solving a skeletal discrepancy as alternative for a surgical option. Mandibular second premolar extraction was often selected as treatment plan when there we very little or no space shortage in lower arch or limited retraction of the lower incisors was required. The primary object of this study was evaluate a pretreatment condition and examine the amount of tooth movement ior a mandibular second premolar extraction in growing patients. Pretreatment and posttreatment lateral cephalograms of 14 cases that had their four first premolar extracted (4/4 group), 15 cases with upper first and lower second premolar extraction (4/5 group) were selected. Structural method superimposition was conducted to evaluate a difference of dental change between 4/4 and 4/5 group. The results were as follows, 1. Pretreatment factor for 4/4 extraction or 4/5 extraction choice included maxillary incisor axis to occlusal plane, Class II molar relationship, IMPA and interincisal angle. 2. The amount of molar anterior movement in 4/5 group was greater than that of 4/4 group(p<0.05). 3. There was no significant difference between 4/4 group and 4/5 group in aspects of maxillary tooth movement(p<0.05).

• The korean journal of orthodontics
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• v.26 no.2 s.55
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• pp.125-139
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• 1996

The author obtained some useful information for the class III treatment from long term observation on the growing patients with class III malocclusion. 8 patients were selected for this study and presentation. From these observation so far my conclusions might be as follows: First in the early correction of the anterior crossbite, considerable forward growth changes were observed in the maxilla Second, as for the growth modification of jaws by orthopedic treatment only limited effects were recognized from the long-term observation Thrid, at early age of patients with anterior crossbite, any data couldn't make me predict the stability after treatment on the long-term basis. Fortunately, however, genial angle showed a marginal possibility of it prediction. Fourth, at an advanced age/ retraction orthopedic force on the mandible and the rapid change in the mandibular position may cause some trouble in the T.M.joint. Finally, the followings are recommendable. As for the anterior crossbite, correct it early as possible, and use orthopedic force under the age of ten. Do not enter the phase II treatment directly. Just wait and observe until the growth were almost completed, focusiong on some important factors such as airway problem, tongue position, and third molar development. Of course, these factors may have some effects on the mandibular growth. for the female, at the age of around 14 years old and the male, around 17 years old, make a final decision whether the patients will continue to be treated orthodontically or surgically Thereby, (I think) the relapse and retreatment problem after treatemnt we have observed so far might be minimized. Furthermore, the active treatment time may be also reduced.

• The korean journal of orthodontics
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• v.34 no.2 s.103
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• pp.197-203
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• 2004

Tweed-Merrifield directional force technology is a very useful concept, especially for the treatment of Glass II malocclusion. It has contributed to treating a favorable counter-clockwise skeletal change and balanced face, while head gear force using high pull J-hook (HPJH) in an appropriate direction is also essential to influence such results. Clinicians have encountered some problems concerning patients' compliance; however skeletal anchorage has been used widely of late because it does not necessitate patients' compliance, yet produces absolute anchorage. In this case, a good facial balance was obtained by Tweed-Merrifield directional force technology using HPJH together with skeletal anchorage, which provided anchorage control in the maxillary posterior area, torque control in the maxillary anterior area, and mandibular response. This indicates 4hat skeletal anchorage can be used to reinforce sagittal and vortical anchorage in the maxillary posterior area during the retraction of anterior teeth. The author used HPJH for torque control, Intrusion, and the bodily movement of maxillary anterior teeth during on masse movement. However, it is thought that such a result nay also be achieved by substituting mini- or microscrews for HPJH. Consequently, Tweed-Merrifield directional force technology using skeletal anchorage for the treatment of Class II malocclusion not only maximiaes the result of treatment but can also minimize patients' compliance.

• Korean journal of applied entomology
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• v.27 no.2
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• pp.103-110
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• 1988

The behavior and circadian rhythm of emergence, copulation and oviposition in the Oriental tobacco budworm (Heliothis assulta Guenee) were studied to obtain the following results. More than three quarters of adults emerged within 3 hours after the light-off. It took about 33 min for an adult to expand and tan its wings after emergence. Adult male showed a sequential pattern of mating behavior, such as antennal movement, wing elevation and vibration, exten¬sion of hairpencils, and tapping of female ovipositor leading to a copulation. However, adult female revealed a rather simple behavior, such as protraction and retraction of her terminal abdomen and vibration of wings. All of the mating took place during the early part of the scotophase, with the peak from 1 hr to 2 hrs after the light-off. But the mating peak in virgin females tended to advance with age. Adult females showed the highest rate of mating among 24 hr-olds and the rate declined with age. The rate of first matings in males gave a very similar pattern to that of females. The duration of copulation was $77\pm$14min. Oviposition occurred throughout the entire scotophase, with the peak during the first 2 hrs. The most nu¬mber of eggs deposited daily was seen on the 3rd day after the mating. Mating rate, number of eggs laid and longevity we~e compared under different sex ratio. Unmated adults lived longer than mated adults.

• Elastomers and Composites
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• v.37 no.1
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• pp.21-30
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• 2002

Core-shell polymers of methyl methacrylate/styrene pair were prepared by sequential emulsion polymerization in the presence of sodium dodecyl benzene sulfonate(SDBS) as an emulsifier using ammonium persulfate(APS) as an initiator. The characteristics of these core-shell polymers were evaluated. Core-shell composite latex has the both properties of core and shell components in a particle, where as polymer blonds or copolymers show a combined properties from the physical properties or two homopolymers. This unique behavior of core-shell composite latex can be used in many industrial fields. However, in preparation of core-shell composite latex, several unexpected phenomina are observed, such as, particle coagulation, low degree of polymerization, and formation of new particles during shell polymerization. To solve the disadvantages, we studied the effects of surfactant concentrations, initiator concentrations, and reaction temperature on the tore-shell structure or PMMA/PSt and PSt/PMMA. Particle size and particle size distribution were measured by using particle size analyzer, and the morphology of the core-shell composite latex was observed by using transmission electron microscope. Glass transition temperature($T_g$) was also measured by using differential scanning calorimeter. To identify the core-shell structure, pH of the composite latex solutions were measured.

• The Korean Journal of Zoology
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• v.31 no.3
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• pp.165-176
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• 1988

Stmcturai changes at the surfaces of oocytes of Pseudopotamilla occelata were examined by electron microscopy. The oocytes, which grow up to the flnai stage in the same coelomic fluid, once released from the ovary at 5 $\mu$ m stage, change in the structure of the vitelilne envelopes. Microvilli were found to change gready in structure, abundance and behaviour dudng oogenesis. Microvilli are short and bifurcated at the previtellogenic stages and grow in size, but the number increases only during previtellogenesis but decreases during vitellogenesis. Glycocaiyx structures begin to form at the tips of microvitli at the early previtellogenic stages and become more abundant as oocytes grow and remain at the final stage of oogenesis. The tips of microvilli are separated from the stems at the late vitellogenic stages to form vesicles simultaneously with retraction of the microvilli. Vitelline envelope consists of outer, intermediate and inner layers at the previtellogenic stages. However, the inner layer becomes thickened and differendated into two sublayers at 80 $\mu$m stage, - while the outer and intermediate layers remain constant in the thickness. These structural changes were presumably the results of functional differentiation of the vitelline envelope throughout oogenesis even in the same milleu.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.39.1-39
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• 1981

The author presents clinical study for 111 cases of tinnitus with pure tone audiometry from Jan. 1, 1978 to Dec. 31, 1980 in department of otolaryngology, Ewha Womans University Hospital. The results were as follows; 1) Male to Female ratio was as 1 : 1, and peak age incidence was in the age group of 21 to 30. 2) Most frequent duration was 1 month to 1 year in the cases of the tinnitus. 3) The patient who complained tinnitus only was 10.0% and the patient who complained tinnitus with hearing impairment was 72.0% in the cases of tinnitus. 4) The affected site in the tinnitus, in order of frequency were; Both ear 38.7% Left ear 32.4% Right ear 28.9% 5) The drum finding, in order frequency were; Normal 48.0% Retraction 33.1% Perforation 8.4% 6) The degree of hearing loss in the audiometry were; Normal 29.2% Moderate severe 22.7% 7) The shape of hearing impairments were; High tone loss 46.9% Flat 33.0% Low tone loss 11.9% 8) The occurrence of $C_{5}$ dip was 11.0% in cases of the tinnitus. 9) The classification of hearing loss were; Sensorineural hearing loss 46.9% Mixed hearing loss 33.1 % Conductive hearing loss 20.1%

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.139-144
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• 2014

This study examined the efficacies of Cynanchum wilfordii and Phlomis umbrosa extracts on serum insulin like growth factor-I (IGF-I) and bone growth by raising rats in vivo. C. wilfordii and P. umbrosa extracts significantly increased serum IGF-I by 42% and 22% than the control, respectively. Treatment with ${\alpha}$-amylase when manufacturing these extracts remarkably increased the concentration of IGF-I by 63% and 36% above the control, respectively. This meant that these extracts, especially ${\alpha}$-amylase treated extracts, maintained a higher level of IGF-I secretion in the treated groups. In addition, increases of 6% in femur length were found after 8 weeks of oral administration with these extracts. These results indicate that C. wilfordii and P. umbrosa extracts have beneficial effects on bone growth via IGF-I.

• Archives of Plastic Surgery
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• v.36 no.5
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• pp.649-653
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• 2009

Purpose: Double - eyelid operation is one of the most common cosmetic operations among Korean patients. In such operations, however, the complexity of and individual differences in the patients' anatomical structures may cause various complications, such as asymmetry, retraction of the eyelid, and the occurrence of a high fold. A high fold occurs frequently, and its correction is not very simple. Many methods have been developed to correct it, and among these, the operation involving the excision of the skin between the previous double - eyelid line and the new double - eyelid line is usually selected by plastic surgeons. In many cases, however, patients have insufficient eyelid skins for this operation. In this study, the authors introduce an operation procedure for high - fold correction that does not involve skin excision Methods: From June 2005 to June 2009, 246 cases were treated with this procedure. After the incision of the new double - eyelid line, dissection was done between the previous scar tissue and the levator aponeurosis. Then the orbital septum, orbital fat or the retro - orbicularis oculi fat was slid down and sutured with a tarsal plate. Such sutures were repeated at four to five points, including the lateral and medial limbus, to prevent the reattachment of the previous scar and to create a new double - eyelid line at the end of the orbital septum. Results: Most of the high - fold patients were satisfied with the procedure described above. Their previous scar was hidden under the new double - eyelid line after the operation. In the six cases, the scar was visible in the patients who had a very high and deep inner line. As such, scar revision was undertaken three months after the operation. It is known that scar revision is also required after an operation involving skin excision in the case of a very high inner - eyelid line. Conclusion: This method is an appropriative procedure for high - fold correction for patients who have insufficient upper - eyelid skin.

• Journal of Chest Surgery
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• v.54 no.5
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• pp.377-382
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• 2021

Background: Subclavian vein (SV) catheterization is a method for the delivery of fluids, drugs, and blood products, venous blood sampling, and central vein pressure monitoring in cardiac surgery. Catheter occlusion is a serious complication of SV catheterization during cardiac surgery, especially after sternal retractor expansion. Methods: In this observational study, 303 patients who had successful right infraclavicular SV catheterization from September 2019 to April 2020 were enrolled to determine the incidence of catheter occlusion. After catheterization, the lumens of all catheters were checked for the ability to infuse and withdraw blood from the catheter before and after sternal retractor expansion. The patients' characteristics, cannulation approach, on-pump or off-pump technique, occlusion of the catheter and its lumens, and any associated complications were recorded. The data were analyzed using IBM SPSS ver. 22.0 (IBM Corp., Armonk, NY, USA). Results: Of the 303 patients studied, 205 were male (67.7%) and 98 were female (32.3%). Catheter occlusion occurred in 11 patients with on-pump cardiopulmonary bypass (CPB) (227 patients) and 4 patients with off-pump CPB (76 patients) (p=0.863). The incidence of catheter occlusion was 4.95% (15 of 303 patients) with no cases of simultaneous 3-lumen occlusion in a catheter. The most commonly occluded lumen was the distal lumen (57.92%). Simultaneous 2-lumen occlusion occurred in 4 patients. Catheter occlusion was found in 3 of 13 malpositioned catheters (23.07%). Conclusion: The current study showed that malpositioning of the catheter tip was a risk factor for catheter occlusion and that the distal lumen of a triple-lumen catheter was the most commonly occluded lumen.