1.Deduction and Verification of Optimal Factors for Stent Structure and Mechanical Reaction Using Finite Element Analysis.
Dong Min JEON ; Won Gyun JUNG ; Han Ki KIM ; Sang Ho KIM ; Il Gyun SHIN ; Hong Seok JANG ; Tae Suk SUH
Korean Journal of Medical Physics 2010;21(2):201-208
Recently, along with technology development of endoscopic equipment, a stent has been developed for the convenience of operation, shortening of recovery times, and reduction of patient's pain. To this end, optimal factors are simulated for the stent structure and mechanical reaction and verified using finite element analysis. In order to compare to present commercialized product such as Zilver (Cook, Bloomington, Indiana, USA) and S.M.A.R.T (Cordis, Bridgewater Towsnhip, New Jersey, USA), mechanical impact factors were determined through Taguchi factor analysis, and flexibility and expandability of all the products including ours were tested using finite element analysis. Also, important factors were sought that fulfill the optimal condition using central composition method of response surface analysis, and optimal design were carried out based on the important factors. From the centra composition method of Response surface analysis, it is found that importat factors for flexibility is stent thickness (T) and unit area (W) and those for expandability is stent thickness (T). In results, important factors for optimum condition are 0.17 mm for stent thickness (T) and 0.09 mm2 for unit area (W). Determined and verified by finite element analysis in out research institute, a stent was manufactured and tested with the results of better flexibility and expandability in optimal condition compared to other products. Recently, As Finite element analysis stent mechanical property assessment for research much proceed. But time and reduce expenses research rarely stent of optimum coditions. In this research, Important factor as mechanical impact factor stent Taguchi factor analysis arrangement to find flexibility with expansibility as Finite element analysis. Also, Using to Center composition method of Response surface method appropriate optimized condition searching for important factor, these considering had design optimized. Production stent time and reduce expenses was able to do the more coincide with optimum conditions. These kind of things as application plan industry of stent development period of time and reduce expenses etc. be of help to many economic development.
Academies and Institutes
;
Finite Element Analysis
;
Indiana
;
New Jersey
;
Pliability
;
Stents
2.Effects of Resilience and Job Satisfaction on Organizational Commitment in Korean-American Registered Nurses.
Kum Sook SEO ; Miyoung KIM ; Jinhwa PARK
Journal of Korean Academy of Nursing Administration 2014;20(1):48-58
PURPOSE: The purpose of this study was to examine the effects of resilience and job satisfaction on organizational commitment in Korean-American registered nurses. METHODS: A cross-sectional study was conducted using a structured questionnaire survey with 203 Korean-American registered nurses living in New York State and New Jersey State. Data were collected from May 8 to August 25, 2012. Collected data were analyzed using t-test, ANOVA, Scheffe test and hierarchical multiple regression. RESULTS: The mean organizational commitment of Korean-American registered nurses was 3.34+/-0.59 out of a possible 5.00. The resilience and job satisfaction were significant variables predicting the level of organizational commitment among Korean-American registered nurses, accounting for 50% of the variability. CONCLUSION: The results of the study indicate that it is necessary to identify factors influencing job satisfaction and develop programs to strengthen personal resilience in order to increase organizational commitment.
Cross-Sectional Studies
;
Humans
;
Job Satisfaction*
;
New Jersey
;
Surveys and Questionnaires
3.Tibial Plateau Coverage in Total Knee Replacement Arthroplasty: Coverage on 12 quadrants.
Hyun Kee CHUNG ; Choong Hyeok CHOI ; Jong Heon KIM ; Kyoung Tae KIM ; Sun Il KIM ; Dong Pyo CHANG
The Journal of the Korean Orthopaedic Association 1999;34(6):1081-1086
PURPOSE: We investigated proximal tibial cutting surface in total knee replacement arthroplasty to improve its coverage and get basic data for developing more adequate tibial components for Koreans. MATERIALS AND METHODS: Of cases of total knee replacement arthroplasty performed by one surgeon between September 1995 and October 1996, we chose 100 cases with no bony defect on resected tibial surface. We traced the outline of tibial resection margin manually and then, decided the most adequate size for each tibial tray from 5 companies, AGC (Biomet, Warsaw, USA), Advantim (Wright medical technology, Arlington, USA), AMK (DePuy, Warsaw, USA), MGII (Zimmer, Indiana, USA), and Series 7000 (Osteonics, New Jersey, USA). We divided the tibial cutting surface with 12 quadrants by 30 degree radian. Then, we overlaped both images (traced tibial surface margin and tibial tray) on the computer and fixed the position when we got the largest coverage of area. From this position we calculated the coverage, underhang and overhang ratios by pixel counts. During this process, we discarded 20 cases because of inadequate overlapping. RESULTS: The overall average ratio of coverage was 82.3%, underhang 17.3%, and overhang 6.0%. The consequence of good coverage and minimal underhang were posterolateral, posteromedial, anterolateral, anteromedial and posterior aspects sequentially. But the posterior side was more overhanged by tibial component than anterior side. CONCLUSION: We feel that improving coverage on posterior and anteromedial portion is key to increasing the coverage ratio of proximal tibia in total knee replacement arthroplasty.
Arthroplasty*
;
Arthroplasty, Replacement, Knee*
;
Indiana
;
New Jersey
;
Tibia
4.Polyethylene Failure Following TKRA.
Hyun Kee CHUNG ; Choong Hyeok CHOI ; Kyeong Tae KIM ; Hoon YEO
Journal of the Korean Knee Society 2001;13(1):30-35
PURPOSE: We purpose to analyze the factors related to the polyethylene failure through the 7 exchanged polyethylene. MATERIALS AND METHODS: We experienced 7 cases of polyethylene failure from Apr. 1988 to Jan. 2000. The average duration of reoperation is 5 year 2 months(1 year 8 months-8 year 11 months), age at primary operation is 62 years old(55-64 years old), weight is 65kg(56-78kg) and height is 155cm(150-162cm). The used prostheses were AGC(Biomet, Warsaw, U.S.A) in 2 patients, AMK(Depuy, Warsaw, U.S.A) in 1 patient, ,MG II(Zimmer, Warsaw, U.S.A) in 1 patient, PFC(Johnson and Johnson, Warsaw U.S.A) in 2 patients and Series 7000(Osteonics, New Jersey, U.S.A.) in 1 patient. RESULTS: The thickness of polyethylene is Smm in 6 patients and 9mm in 1 patient. All of prostheses are cruciate retaining type with relatively flat surface geometry and low-height intercondylar eminence, and the minimal thickness of each system. CONCLUSION: We consider that the thicker polyethylene should be used when feasible in order to avoid reoperation which is caused by accelerated wear of polyethylene, and early detection of polyethylene wear is important. This can be got through knee standing AP, fluroscopic evaluation with varus and valgus stress.
Humans
;
Knee
;
New Jersey
;
Polyethylene*
;
Prostheses and Implants
;
Reoperation
5.Endoscopic Dacryocystorhinostomy Using Ultrasonic Bone Aspirator.
Soo Jung LEE ; Jung Yup KIM ; Jae Hwan KWON
Journal of the Korean Ophthalmological Society 2015;56(11):1667-1670
PURPOSE: To report the results of 15 endoscopic dacryocystorhinostomy (eDCR) cases using ultrasonic bone aspirator (UBA) and evaluate the UBA efficiency in these surgeries. METHODS: Fifteen eyes of 12 patients presenting with nasolacrimal duct obstruction were evaluated in the present study. eDCR and osteotomy were performed using UBA (Cusa excel, Integra, New Jersey, NJ, USA) from January 2014 to June 2014. RESULTS: All the patients showed complete resolution of the epiphora. There were no complications or recurrences for a minimum of 10 months postoperatively. CONCLUSIONS: This is the first report on eDCR using UBA. The surgeries were successful and no complications were observed. eDCR using UBA is an easy, safe and effective technique with minimal heat production, minimal damage to the surrounding soft tissue and quick and precise bone removal.
Dacryocystorhinostomy*
;
Humans
;
Lacrimal Apparatus Diseases
;
Nasolacrimal Duct
;
New Jersey
;
Osteotomy
;
Recurrence
;
Thermogenesis
;
Ultrasonics*
6.The Clinical Results of Primary Cementless Total Hip Arthroplasties Using Omnifit Microstructured System: A Five-Year Clinical Follow-Up Study and Roentgenographic Analysis.
Young Min KIM ; Hee Joong KIM ; Han Koo LEE ; In Ho CHOI ; Sang Hoon LEE ; Tae Joon CHO ; Kwang CHANG ; Jeong Joon YOO
The Journal of the Korean Orthopaedic Association 1998;33(2):221-231
We reviewed 64 primary cementless porous-coated total hip arthroplasties using Omnifit Microstructured system (Osteonics, Allendale, New Jersey, U.S.A.). They were followed up for an average of 6 years (range, 5 years to 7 years and 11 months). The average Harris score was improved from 60.8 preoperatively to 86.2 postoperatively. The results were excellent in 3i cases(48.4%), good in 22 cases(34.4%), fair in 7 cases(I0.9%) and poor in 4 cases(6.3%). According to the last t'ollow-up radiologic findings, 61 cases(95.3%) were considered to he stable bony fixation and 3 cases(4.7%) to he stahle fibrous fixation. Neither unstahle fixation nor loosening of component was ohserved. But osteolysis was occured in 32 cases(50.0%) around prosthetic stem and in l6 cases(25.0%) around prosthetic cup. The mean linear wear of polyethylene insert was 1.46mm(range, 0.1 mm to 5.83mm). the linear wear rate was 0.23mm/year (range, 0.02mm/year to 0.81mm/year) and the excessive wear more than 2mm was ohserved in 15 cases. Reoperation was required in 18 cases(28. l%) after followup of 6 years (range, 4 years and 3 months to 7 years and 2 months); 11 had been reoperated and 7 were awaiting reoperation. The causes of reoperation were osteolysis and excessive polyethylene wear (more than 2mm) in 15 cases and osteolysis only in 3 cases. The result of primary cementless porous-coated total hip arthroplasties using Omnifit Microstructured system was acceptahle up to 5 years, but then increasing reoperation appeared to he due to polyethylene wear and osteolysis. Therefore, the routine follow-up of cementless porous-coated total hip arthroplasties is essential, especially after 5 years in order to detect and manage such prohlems early. And the modification in materials suhstituting metal-on-polyethylene articulation is required to reduce them.
Arthroplasty*
;
Arthroplasty, Replacement, Hip
;
Follow-Up Studies*
;
Hip*
;
New Jersey
;
Osteolysis
;
Polyethylene
;
Reoperation
7.Tibial Plateau Coverage in total knee Replacement arthroplasty.
Hyunkee CHUNG ; Choonghyeok CHOI ; Jongheon KIM ; Kyoungtae KIM ; Sunil KIM ; Kongpyo CHANG
Journal of the Korean Knee Society 1998;10(2):135-140
Maximizing tibial coverage is an important consideration in total knee replacement arthroplasty to provide stability and even load transfer and to improve long term survival rate of the implants. We evaluated the coverage, underhang and overhang ratio for the proximal tibial resection surface during total knee replacement arthroplasty in Koreans. After cutting the proximal tibia, the outline of tibial resection surface was traced manually. We compared 5 tibial tray designs, AGC(Biomet, Warsaw, U.S.A.), Advantim(Wright medical technology, Arlington, U.S.A.), AMK(DePuy, Warsaw, U.S.A), MG II(Zimmer, Indiana, U.S.A.), Series 7000(Osteonics, New Jersey, U.S.A.), which have been commercially used in Korea for total knee replacement arthroplasty. The average percentage of coverage area were 83.3% in AGC, 81.6% in AMK, 80.3% in MG II, 80.2% in Advantim and 76.9% in Series 7000. The average percentage of underhang were 16.7% in AGC, 18.4% in AMK, 19.6% in MG II, 19.8% in Advantim and 23,1% in Series 7000. The average percentage of overhang were measured 7.97% in AGC, 7.86% in AMK, 8.01% in MG II, 8.77% in Advantim and 10.14% in Series 7000. So average coverage percentage of tibial cutting surface was 80.5% in Koreans. The factors which affect the optimal coverage, were the shape, dimensional interval of tibial trays and the number of practically useful tibial trays for Koreans.
Arthroplasty*
;
Arthroplasty, Replacement, Knee*
;
Indiana
;
Korea
;
New Jersey
;
Survival Rate
;
Tibia
8.Clinical Effects of Dihydroxyacetone Solution for Vitiligo Patients.
Hyo Jin KIM ; Hyun Chul SUNG ; Gun Yoen NA ; Weon Ju LEE ; Seok jong LEE ; Do Won KIM
Korean Journal of Dermatology 2006;44(2):131-136
BACKGROUND: Vitiligo is a common, acquired, progressive depigmenting disorder. It is not physically destructive, however often leaves patients visibly disfigured by uneven color of the exposed areas such as the face or hands, especially in colored races. Most treatment protocols for vitiligo usually require a long treatment duration and do not result in complete repigmentation. Therefore, cosmetically-acceptable and easily-usable alternatives are needed. OBJECTIVE: The purpose of this study was to evaluate the clinical effects of dihydroxyacetone (DHA) solution for Korean vitiligo patients. METHODS: Thirty eight patients were treated with DHA, who suffered from vitiligo affecting the face, hands, trunk and thighs. They were instructed to apply DHA once every other day. Thereafter, the number of applications and intervals were adjusted according to the status of coloring. We surveyed the grade of subjective satisfaction, and also measured the L*, a* and b* values of normal skin, vitiligo lesion, DHA-applied site (n=10) and autologous suction blister graft site (n=6) and compared color difference between those areas using the Minolta Chromoameter gap (Minolta, Ramsey, New Jersey, USA). RESULTS: The characteristic pigmentation showed an acceptable cosmetic improvement in 27 of the 38 patients after 4-6 weeks of treatment. L* value was improved after DHA application, while a* and b* values showed more discrepancy than normal skin color. As a whole, the color difference between normal skin and vitiligo lesion was decreased after DHA application. CONCLUSION: The results suggest that DHA could be used for Korean vitiligo patients as an additional option for cosmetic correction.
Blister
;
Clinical Protocols
;
Continental Population Groups
;
Dihydroxyacetone*
;
Hand
;
Humans
;
New Jersey
;
Pigmentation
;
Skin
;
Suction
;
Thigh
;
Transplants
;
Vitiligo*
9.A Study on Body Image Perception and Eating Disorders by Birth-Place and the Length of Residence in USA in Korean American College Students.
Ho Kyung RYU ; Isobel R CONTENTO
Korean Journal of Community Nutrition 2011;16(1):113-125
This study was conducted to compare the body image perception, weight control experiences and the eating disorders according to where they were born, and the length of residence in USA among Korean-American college students. Three hundred college students participated in the study: 144 males and 156 females, 122 America-born (AB) and 171 Korea-born (KB) who live in New York City and New Jersey. Subjects responded to a self-administered questionnaire. The results showed that the ratio of overweight (23.2%) and obesity (26.8%) of males was higher than females' (16.1% and 6.3%, respectively). There were no significant differences according to born-place or the length of residence in USA of KB. People who had tried to control their weight were 58%. The ratio of weight control experiences of females (72.4%) was higher than males' (42.4%) as well as people who were normal or underweight than who were overweight or obesity. There were no significant differences according to born-place or the length of the residence in the USA of KB. In body image perception, the subjects who were normal and underweight overestimated their body figure, and the subjects who were overweight and obese underestimated their body figure. The desired and ideal figure of female students was significantly thinner than the current figure and also that of male students. There were no significant differences according to born-place or the length of the residence in USA of KB. The ratio of eating disorder was 8.7%, and females had higher percentage than males. And shorter they lived in USA, the percentage of eating disorder was higher.
Asian Americans
;
Body Image
;
Eating
;
Feeding and Eating Disorders
;
Female
;
Humans
;
Male
;
New Jersey
;
New York City
;
Obesity
;
Overweight
;
Surveys and Questionnaires
;
Thinness
;
Weight Perception
10.Effects of Flow Rate and Dilution during Anesthesia Induction with Propofol.
Ho Yeong KIL ; Hoon PARK ; Hyun Hwa LEE ; Tae Hyun HAN ; Bong Soo CHAE ; Sung Jun HONG
Korean Journal of Anesthesiology 2001;41(6):676-680
BACKGROUND: The Pharmacokinetic parameter and the degree of dilution can have an effect on induction time and vital signs during general anesthesia with propofol. Induction time, induction dose and vital signs according to various flow rates and the degrees of dilution during anesthesia induction with propofol were studied. METHODS: After institutional review board approval, and informed consent, One hundred and eighty ASA I or II adult patients undergoing elective surgery were assigned to one of four groups according to their degree of dilution. One group was undiluted and another 3 groups were diluted with 5% D/W (1:1, 1:2, 1:3). Each group was divided into 3 subgroups according to their flow rates of 25, 50, 100 mg/kg/hr. No premedication was given. With routine monitoring including radial arterial cannulation, propofol was infused using a syringe or infusion pump (Becton Dickinson pump, Franklin Lakes New Jersey, USA) in the previously designed manner. Induction time defined as loss of eyelash reflex, induction dose, and vital signs were checked. RESULTS: The faster the flow rate and the more diluted a drug, the shorter the induction time. The faster the flow rate and the less diluted a drug, the greater the induction dose. The more diluted a drug, the less the decrease in systolic blood pressure. Flow rate has little influenced decreasing systolic blood pressure. CONCLUSIONS: We concluded that it is reasonable to reduce flow rate and dilute propofol when the hemodynamic changes of the patient should be minimal during propofol based sedation/anesthesia.
Adult
;
Anesthesia*
;
Anesthesia, General
;
Blood Pressure
;
Catheterization
;
Ethics Committees, Research
;
Hemodynamics
;
Humans
;
Informed Consent
;
Infusion Pumps
;
Lakes
;
New Jersey
;
Premedication
;
Propofol*
;
Reflex
;
Syringes
;
Vital Signs