• Journal of the Korea Concrete Institute
• /
• v.22 no.3
• /
• pp.325-333
• /
• 2010

In this study, new moment-resisting precast concrete beam-column joint made up of hybrid steel concrete was developed and tested. This beam-column joint is proposed for use in moderate seismic regions. It has square hollow tubular section in concrete column and connecting plate in precast U-beam. The steel elements in column and beam members were connected using bolt. Furthermore, in order to prevent the premature failure of concrete in hybrid steel-concrete connection, ECC(engineered cementitious composite) was used. An experimental study was carried out investigating the joint behavior subjected to reversed cyclic loading and constant axial compressive load. Two precast beam-column joint specimens and monolithic reinforced concrete joint specimen were tested. The variables for interior joints were cast-in-situ concrete area and transverse reinforcement within the joint. Tests were carried out under displacement controlled reverse cyclic load with a constant axial load. Joint performance is evaluated on the basis of connection strength, stiffness, energy dissipation, and displacement capacity. The test results showed that significant differences in structural behavior between the two types of connection because of different bonding characteristics between steel and concrete; steel and ECC. The proposed joint detail can induce to move the plastic hinge out of the ECC and steel plate. And proposed precast connection showed better performance than the monolithic connection by providing sufficient moment-resisting behavior suitable for applications in moderate seismic regions.

• Clinical and Experimental Reproductive Medicine
• /
• v.30 no.1
• /
• pp.85-93
• /
• 2003

Objective : To evaluate the safety and efficacy of selective fetal reduction (SFR) and compare the outcome of twin pregnancy after SFR in multiple pregnancy induced by assisted reproductive technology (ART) with that of natural twin pregnancy. Methods : From September 1995 to March 2002 in Ajou University Hospital, SFR was performed in 79 patients whose gestational sacs were more than 3. Of these 79 patients, 47 patents resulted in twin pregnancy after SFR. SFR was performed using transvaginal intracardiac KCl injection at gestational age of $6{\sim}9$ weeks. Control group was composed of 264 patients with natural twin pregnancy, who delivered after intrauterine pregnancy at 24 weeks, from June 1994 through December 2002. We compared Obstetric and perinatal outcomes between SFR group and natural twin group. Results: Among 47 patients with twin pregnancy after SFR, 2 spontaneous abortion were occurred at intrauterine pregnancy at 8 and 19 weeks. Obstetrical and perinatal outcomes were available in 43 patients. Single intrauterine fetal death was occurred in 1 of 43 (2.3%) patients in SFR group. Incidence of preterm labor, premature rupture of membrane, preeclampsia and placenta previa were similar, but gestational diabetes mellitus (GDM) was occurred more frequently in SFR group (3 (7.0%) vs 4 (1.5%), p=0.02). Mean gestational age, mean birth weight, incidence of discordancy, use of intubation and ventilation, incidence of fetal anomaly, low (<7) Apgar score and intrauterine growth restriction were similar in both groups. Conclusion: Twin pregnancy after SFR has the increased incidence for GDM but other obstetric and perinatal outcome was similar compared with natural twin pregnancy. So SFR is a safe and effective procedure, so we suggest SFR is needed in multifetal pregnancy more than triplet.

• Clinical and Experimental Reproductive Medicine
• /
• v.31 no.4
• /
• pp.225-234
• /
• 2004

Objectives: To evaluate the efficacy of GnRH antagonist cetrorelix in women undergoing controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) and to determine changes in serum hormone concentrations during cetrorelix administration. Methods: We performed a clinical trial on 30 patients undergoing COH with highly purified follicular stimulating hormone (HP-FSH) and gonadotropin releasing hormone antagonist (GnRHant), cetrorelix. FSH was administrated from day 2 or 3 of cycle with fixed dose and adjusted according to individual response. 0.25 mg of cetrorelix was injected daily subcutaneously from stimulation day 5 until the day of hCG administration. Daily ultrasound monitoring was performed for growing follicles and serum levels of luteinizing hormone (LH), estradiol ($E_2$) and progesterone were measured daily during cetrorelix administration. Up to 4 embryos were transferred. Results: Mean age of enrolled patients was $32.0{\pm}3.4$ years (mean $\pm$ S.D.). All of 30 patients underwent oocyte pick-up, and embryo transfer was done in 28 patients. The total and mean numbers of received oocytes were 196 and $6.5{\pm}4.7$, the number of fertilized eggs was 111, and the fertilization rate was 56.6%. Total duration of FSH administration was $9.2{\pm}2.2$ days and mean of $24.3{\pm}7.7$ ampules of HP-FSH was administered. Total duration of cetrorelix administration was $5.7{\pm}1.9$ days. Serum LH and progesterone levels were maintained in the range of $1.4{\sim}2.9\;mIU/mL$ and $0.3{\sim}0.6\;ng/mL$, which respectively reflected effective prevention of premature LH surge. Clinical pregnancies were achieved in 9 patients, and overall clinical pregnancy rate was 30.0% per oocyte retrieval, and 32.1% per embryo transfer. Conclusion: GnRH antagonist is safe and convenient for COH for IVF-ET and effective with optimal pregnancy rate.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.26 no.2
• /
• pp.446-452
• /
• 1999

Ectopic eruption of the first permanent molar means the first permanent molar assumes an atypical path of eruption resulting in premature atypical resorption of the second primary molar. If the reversible eruption does not occur, early loss of the second primary molars results in space loss, mesial tipping of the first permanent molar, impaction of the second premolar, buccal segment crowding and overeruption of opposing tooth. The main objectives of treatment are (1) to prevent loss of the second deciduous molars so it can continue to serve as a space maintainer and (2) to regain lost arch length, allowing the second premolar to erupt into normal position. The optimal treatment approach depends on a number of factors including the clinical eruption status of /6/, the change in position of /6/, the amount of enamel ledge of /E/ entrapping /6/, the mobility of /E/, and the presence of pain or infection. Unilateral appliance to correct the mesial angulation of ectopic permanent first molars, as in the majority of the appliance designs, would produce a resultant force that would further enhance the space loss. A bilateral support similar to the holding arch design is recommended to maximize the anchorage. These case reports present the successful result of preserving space for the second premolar in treatment of ectopic eruption of the first permanent molar using Halterman appliance with bilateral anchorage on patients visiting department of pediatric dentistry in Samsung Medical Center.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.37 no.2
• /
• pp.260-266
• /
• 2010

Trauma to the primary teeth may have an effect on the successive permanent teeth. Thus, the treatment plans should be focused on safety of their permanent teeth. The degree of developmental disturbances in those permanent teeth depends upon many factors including the age of the children, developmental conditions of the affected teeth, types and severities of trauma and time interval from the moment of trauma to the initial treatment the patients received. The complications of the effected permanent teeth vary from the mild enamel hypoplasia to the premature finishing of teeth development. In this study, children whose ages were 33 months, 5 years, and 26 months presented the developmental disturbances to their permanent teeth, which resulted from the trauma to the primary teeth: the intrusion, the avulsion, and the subluxation. There showed a mild complication in the case of subluxation resulting in enamel hypoplasia, but, the more severe complication of the root dilacerations occurred in the case of intrusion. Furthermore, the 5-year-old patient whose primary dentition was near in transition period to the permanent one, the more complicated problem such as stop of root development of the permanent teeth was resulted from the avulsion. Thus, one should assume that the types of trauma and the age of the children at the moment of trauma have different effects on those successive permanent teeth. In conclusion, when the trauma that causes changes in the position of primary teeth happened, it is important to arrange an appropriate treatment procedure considering the types of trauma and the developmental conditions of the permanent teeth.

• Child Health Nursing Research
• /
• v.20 no.3
• /
• pp.225-235
• /
• 2014

Purpose: The purpose of this study was to analysis the effects of nasal Continuous Postive Airway Pressure (nCPAP) for preterm infants using systematic review and meta-analysis. Methods: Thirteen peer-reviewed journals including preterm infants and apnea and nCPAP published between 1973 and 2013 were included. Effect size and statistics of homogeneity were done using STATA 10.0. Results: The design for 9 studies was Randomized Control Trial. In most of studies the pressure of nCPAP was set to 4-6 cm$H_2O$. The effect size of 5 studies for the effect on apnea rate using nCPAP compared to nasal Intermittent Positive Pressure Ventilator (nIPPV) showed that the Standardized Mean Difference (SMD) was -0.11 and was not significantly different (Z=0.41, p=.680). But the difference in nCPAP for nasal Synchronizes Intermittent Positive Pressure Ventilator (nSIPPV) (subgroup) was significant (SMD=-.44). The effect size of 7 studies on effect for ventilator weaning of using nCPAP compared to nIPPV showed the Risk Ratio (RR) as 1.60 and was not significantly different (Z=1.12, p=.268). But the difference between nCPAP and nSIPPV (subgroup) was significant (RR=3.94). Conclusion: The results indicate a need for an advanced care system and suggest continuous studies of apnea in preterm infants.

• The Journal of the Korean bone and joint tumor society
• /
• v.6 no.1
• /
• pp.41-46
• /
• 2000

We experienced the case of familiar hypercholesterolemia with multiple xanthomas which was treated by combined surgical and medical therapy. He was 26-year-old male patient of familiar hypercholesterolemia with multiple xanthomas in 22 sites on whole body, and was treated by 17 surgical excisions of the xanthomas and by medical therapy of the hypercholesterolemia. There was a normal healing process of the surgical wounds. Continual postoperative medical therapy of the hypercholesterolemia was done. There was no recurrence of the symptoms during more than 13 months of follow-up. But the serum level of the cholesterol was not lowered significantly, so we are treating him with drug therapy. Familial hypercholesterolemia is caused by a specific disorder of lipid metabolism, and is characterized by increased LDL cholesterol, tendon xanthomas, coronary disease associated with autosomal dominant transmission. Xanthomas usually appear in the second decade of life with familiar hypercholesterolemia which may have high risk for premature coronary atherosclerosis, which might be prevented with early diagnosis and medical treatment. So, orthopedic surgeons do not only excise the xanthomatosis surgically but also can diagnose the underlying hypercholesterolemia.

• Korean Journal of Clinical Pharmacy
• /
• v.15 no.1
• /
• pp.9-20
• /
• 2005

Cholestatic liver disease is a frequent complication of prolonged parenteral nutrition, especially in premature infants. Numerous factors have been cited as contributing to TPN associated cholestasis. However the exact etiology remains obscure. Ursodeoxycholic acid (UDCA) has been reported to be beneficial far children and adults with various chronic cholestatic liver disease. The aim of this prospective, randomized, double-blind, placebo-controlled study was to determine the preventive effects of UDCA administration during TPN. Seventeen pediatric patients (8 boys and 9 girls) undergoing TPN were assigned randomly to two groups, UDCA and placebo group. UDCA group (n=9) received 15 mg/kg/day UDCA and placebo group (n=8) received 15 mg/kg/day placebo enterally during the TPN period. Liver function tests (total bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase) were per-formed before TPN and weekly or three times a week. The patients' weights, complete blood count, composition of TPN, and the infusion rate of TPN and lipid were monitored everyday. Calcium and phosphate were monitored twice a week. Between the UDCA and placebo groups, there were no differences in weight at the onset of TPN, birth weight, duration of TPN, respiratory distress syndrome associated with prematurity, age at the onset of TPN, gestational age, the number of days the patients received antibiotics, the number of patients received enteral nutritions and the composition of TPN. In contrast, there was a significant difference between the UDCA and placebo groups in alanine aminotransferase levels during TPN. It doesn't seem that UDCA administration during TPN correlates directly with improvement of liver function. But the preventive administration of UDCA may be effective in reducing liver enzyme, alanine aminotransferase and has no adverse effects.

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.1 s.35
• /
• pp.47-56
• /
• 2007

The Build-Transfer-Lease(BTL) system is a new way of attracting private capital to social infrastructure construction projects. Private companies will get back their investment by leasing facilities to the government. In January 2005, government introduces a 'Korean New Deal Policy' to initiate BTL system in the field of social infrastructure development such as education, public welfare, housing, culture etc. As BTL being still in premature phase, thus it is lack of knowledge in BTL and there is no such studies about problems and impacts of BTL projects. However, there could be so many problems underlying within BTL projects. Therefore, the purpose of this paper is to identify various risk factors during implementation of BTL projects. For this purpose, five BTL undertaking projects were studied. Field survey was conducted based-on interview instruments. Prevailing risk factors in operating the BTL Project were collected from the both officials of project promoters and concessionaires. In addition, a distinct need has emerged for analysis of risk factors for BTL projects. Based on real cases, this study resulted in risk factors influencing every phases and grouped risk factors into each phase. Moreover, this study also perform sensitivity analysis in order to know how risk factors affect to BTL projects. From analyzing the data, the study addresses that both major BTL project participants 'the competent authority' and 'Special purpose company(SPC)' have many problems and difficulties to operate the projects.

• Neonatal Medicine
• /
• v.18 no.2
• /
• pp.234-239
• /
• 2011

Purpose: Ibuprofen is used for prevention and treatment of patent ductus arteriosus as an alternative drug of indomethacin in very premature infants. We aimed to determine the effect of prophylactic ibuprofen on patent ductus arteriosus and clinical outcomes in preterm infants less than 1,250 g. Methods: A retrospective review of 39 preterm infants who were admitted to our neonatal intensive care unit from November 2009 to July 2010 was performed. Patients were divided into a prophylactic group (n=13) and a matched historical control group (n=26), where prophylactic ibuprofen were administrated within 24 hours after birth. The rate of ductal closure, side-effects of drug treatment and clinical outcomes were compared between two groups. Results: Comparison of the prophylactic and control groups revealed no significant differences in the rate of ductal closure (69.2% vs 77.7%, P=0.825) and surgical ligation (23.1% vs 30.8%, P=0.719). Occurrence of bowel perforation was more frequent in the prophylactic group than the control group, but was not significant (30.8% vs 11.5%, P=0.194). The frequency of intraventricular hemorrhage (grade${\geq}$3) and other outcomes did not differ between the groups. Conclusion: Ibuprofen prophylaxis in preterm infants did not decrease the rate of ductal closure, the need for surgical ligation and the incidence of intraventricular hemorrhage. Further studies are needed to investigate the beneficial effect and associated adverse events attributed to ibuprofen prophylaxis.