• Clinical and Experimental Reproductive Medicine
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• v.30 no.3
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• pp.193-202
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• 2003

Objective: To evaluate the difference of implantation rate (IR) and clinical pregnancy rate (CPR) between two protocols of endometrial preperation in women undergoing frozen-thawed embryo transfer (FET) cycles. Methods: This study was performed during the different time periods: A retrospective study from January 2000 to June 2001 (phase I) and a prospective study from July 2001 to March 2002 (phase II). All the patients received estradiol valerate (6 mg p.o. daily) starting from day 1 or 2 of the menstrual cycle without pituitary down regulation. Progesterone was administered around day 14 after sonographic confirmation of endometrial thickness $\geq$7 mm and no growing follicle. In Group A (n=88, 99 cycles) of phase I, progesterone was administered i.m. at a dose of 50 mg daily from one day prior to thawing of pronuclear (PN) stage frozen embryo or three days prior to thawing of 6-8 cell stage frozen embryo and then each stage embryos were trasnsferred 2 days or 1 day later after thawing. In Group B (n=246, 299 cycles) of phase I, patients recieved progesterone 100 mg i.m. from one day earlier than group A; two days prior to PN embryo thawing, four days prior to of 6-8 cell embryo thawing. During the phase II, to exclude any differences in embryo transfer procedures, in Group 1 (n=23, 28 cycles) of phase II embryo was transfered by one who have used the progesterone protocol since the phase I. In Group 2 (n=122, 139 cycles) of phase II embryo was transfered by one who use the progesterone protocol from the phase II. Results: When compared across the phase and group, there were no significant differences in the characteristics. During the phase I, there were significant increase in IR (14.4% vs 5.9%, p=0.001) and CPR (28.3% vs 14.5%, p=0.000) in group A. During the phases II, IR (11.8% vs 10.6%) and CPR (27.6% vs 27.3%) show no differences between two groups. Conclusions: In FET cycles, IR and CPR are increased significantly by the change of dosage and timing of progesterone administraton. And the timing is considered to be more important factor because the dosage of progesterone did not affect implantation window in previous studies. Therefore, we suggest that progesterone administration in FET cycle should begin from one day prior to PN stage embryo thawing and three days prior to 6-8 cell stage embryo thawing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.560-569
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• 2016

Purpose The purpose of this study was not only to explore the factors associated with the survival of OHCA(Out-of-hospital Cardiac Arrest), but to provide ideas for improving the operation of emergency medical system in Korea. Method 90,734 OHCAs(Out-of-hospital Cardiac Arrest) with a cardiac etiology, who had been transported by 119 EMS ambulances for seven years from 2006 to 2012 in Korea, were analyzed. The data had a multilevel structure in that patient's survival in the same region is interrelated, so two-level (patient-region) logistic regression analysis was applied to adjust this correlation. Results The adjusted OR in group who were given CPR(Cardiopulmonary Resuscitation) by a bystander were 1.40 for survival to discharge. In addition, the adjusted OR in the group with an implementation of AED (automated external defibrillator) before arriving in hospital was 2.98 for survival to discharge. we categorized some continuous variables (number of emergency physician, OHCAs volume fo hospital, area deprivation level) into five quintiles. The adjusted OR in the number of emergency physician compared with Q1(lowest) was 1.29(Q2), 2.89(Q3), 3.39(Q4), 4.07(Q5), respectively. the adjusted OR in OHCAs volume of each hospital compared with Q1(lowest) was 2.06(Q2), 3.06(Q3), 3.46(Q4), 4.36(Q5), respectively. Lastly, the adjusted OR in deprivation level compared with Q1(least deprived area) was 0.72(Q4), 0.64(Q5) so that the adjusted OR of survival to discharge tended to decrease in more deprived districts. Conclusion The survival to discharge was better significantly in group given CPR by a bystander and with the implementation of AED before arriving in hospital. The survival to discharge tended to be significantly better in hospitals with a larger number of emergency physicians and higher volume of OHCAs in less deprived districts.

• Journal of radiological science and technology
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• v.35 no.1
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• pp.51-57
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• 2012

In this experiment, we investigated 82 patients who suffered adverse reactions due to contrast medium. We selected the subjects out of 21,178 people who had an intravenous injection of contrast medium to undergo MDCT examination at one university hospital in Busan in 2007. As a result, the largest groups of the patients were as follows. 52.4% of the patients were male when classify by gender; 28.0% of the patients were 50's by age; 45% of the patients got when it was spring(April and March); 75.6% of the patients had a side effects when the speed of injection is 2.5mL/sec; 58.5% of the patients were suffered when the volume of injected contrast medium is over 130mL. Urticaria was the main symptom of side effect as 26.8%. And the main treatment for the effect was alleviating the symptoms before making patients to return home. Thus, practical preventive measures are needed as follows : use the OCS system to observe warning signs at risky patients, secure warming spaces for patients to cope with season changing, prepare enough emergency kits for the patients in danger, and establish CPR call systems, explain the risk of contrast medium and get agree about using contrast medium.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.3
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• pp.197-205
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• 2007

Objective: This study evaluated the pregnancy and implantation rates in fresh IVF-ET cycles or frozen-thawed ET (F-ET) cycles based on serum estradiol concentrations of controlled ovarian hyperstimulation (COH). Methods: Clinical outcomes of 1,565 cycles of fresh IVF-ET with COH and 670 cycles of F-ET were retrospectively analyzed. Serum estradiol levels on the day of human chorionic gonadotropin (hCG) administration were categorized into Group-A (1,000$\sim$2,000 pg/ml), Group-B (2,000$\sim$3,000 pg/ml), Group-C (3,000$\sim$4,000 pg/ml) and Group-D (> 4,000 pg/ml). Clinical pregnancy (CPR), implantation (IR) and delivery rates (DR) were compared among four groups subdivided into younger (< 35 years) and older ($\geq$ 35 years) women. Statistical analysis was performed by Student's t-test and chi-square test. Results: Overall clinical outcomes with fresh IVF-ET and F-ET cycles were similar: 41.2% vs 44.8% of CPR, 18.8% vs 19.6% of JR, and 33.2% vs 34.5% of DR, respectively. There were no significant differences in the clinical outcomes of all four groups between fresh IVF-ET and F-ET cycles of younger women according to the estradiol levels. However, the clinical outcomes of F-ET cycles of older women in Group-D were significantly higher than those of fresh IVF-ET cycles (51.3% vs 25.0% of CPR*, 18.6% vs 9.9% of IR and 33.3% vs 19.4% of DR;* p<0.05). Conclusion: Our results demonstrated that supraphysiological levels of estradiol during COH in fresh IVF-ET cycles of older women ($\geq$ 35 years) may be detrimental to implantation environments of endometrium and clinical outcomes, which could be improved by F-ET cycles.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.1
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• pp.49-56
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• 2010

Objective: To investigate assisted reproductive technology (ART) outcomes in women with WHO class I anovulation compared with control group. Design: Retrospective case-control study. Methods: Twenty-three infertile women with hypogonadotropic hypogonadism (H-H) who undertook ART procedure from August 2003 to January 2009 were enrolled in this study. A total of 59 cycles (H-H group) were included; Intra-uterine insemination with super-ovulation (SO-IUI, 32 cycles), in vitro fertilization with fresh embryo transfer (IVF-ET, 18 cycles) and subsequent frozenthawed embryo transfer (FET, 9 cycles). Age and BMI matched 146 cycles of infertile women were collected as control group; 64 cycles of unexplained infertile women for SO-IUI and 54 cycles of IVF-ET and 28 cycles of FET with tubal factor. We compared ART and pregnancy outcomes such as clinical pregnancy rate (CPR), clinical abortion rate (CAR), and live birth rate (LBR) between the two groups. Results: There was no difference in the mean age ($32.7{\pm}3.3$ vs. $32.6{\pm}2.7$ yrs) and BMI ($21.0{\pm}3.1$ vs. $20.8{\pm}3.1kg/m^2$) between two groups. Mean levels of basal LH, FSH, and $E_2$ in H-H group were $0.62{\pm}0.35$ mIU/ml, $2.60{\pm}2.30$ mIU/ml and $10.1{\pm}8.2$ pg/ml, respectively. For ovarian stimulation, H-H group needed higher total amount of gonadotropin injected and longer duration for ovarian stimulation (p<0.001). In SO-IUI cycles, there was no significant difference of CPR, CAR, and LBR between the two groups. In IVF-ET treatment, H-H group presented higher mean $E_2$ level on hCG day ($3104.8{\pm}1020.2$ pg/ml vs. $1878.3{\pm}1197.7$ pg/ml, p<0.001) with lower CPR (16.7 vs. 37.0%, p=0.11) and LBR (5.6 vs. 33.3%, p=0.02) and higher CAR (66.7 vs. 10.0%, p=0.02) compared with the control group. However, subsequent FET cycles showed no significant difference of CPR, CAR, and LBR between the two groups. Conclusion: H-H patients need higher dosage of gonadotropin and longer duration for ovarian stimulation compared with the control groups. Significantly poor pregnancy outcomes in IVF-ET cycles of H-H group may be due to detrimental endometrial factors caused by higher $E_2$ level and the absence of previous hormonal exposure on endometrium.

• Current Photovoltaic Research
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• v.4 no.3
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• pp.114-118
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• 2016

$Cu_{1.8}Zn_{1.2}(Sn_{1-x}Ge_x)S_4$ (CZTGeS) nanocrystals were mechanochemically synthesized from elemental precursor powders without using any organic solvents and any additives. The composition of CZTGeS nanocrystals were systematically varied with different Ge mole fraction (x) from 0.1 to 0.9. The XRD, Raman spectroscopy, high-resolution TEM, and diffuse reflectance studies show that the as-synthesized CZTGeS nanocrystals exhibited consistent changes in various structural and optical properties as a function of x, such as lattice parameters, wave numbers for $A_1$ Raman vibration mode, interplanar distances (d-spacing), and optical bandgap energies. The bandgap energy of the synthesized CZTGeS nanocrystals gradually increases from 1.40 to 1.61 eV with increasing x from 0.1 to 0.9, demonstrating that Ge-doping is useful means to tune the bandgap of mechanochemically synthesized nanocrystals-based kesterite thin-film solar cells. The preliminary solar cell performance is presented with an efficiency of 3.66%.

• Current Photovoltaic Research
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• v.8 no.2
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• pp.54-59
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• 2020

Within the IEA (International Energy Agency) PVPS (Photovoltaic Power System) Programme Task 15, 'Enabling Framework for the Acceleration of BIPV,' a round-robin action focusing on the performance of vertical BIPV elements as a facade in different climatic environments was performed. The performance of identical (both, in construction and bill of materials (BOM)) glass-to-glass c-Si BIPV elements was monitored at seven outdoor test sites in 6 different countries in Europe and Asia. In this work, the comprehensive results of the electrical and corresponding meteorological data will be presented and discussed. The monitored data were merged, processed, and filtered for further analysis. The analysis includes the chracteristics of the module temperatures and the in-plane irradiation at the outdoor test locations, mean daily PR per test module, time series of mean daily performance ratio coefficients, and monthly yield.

• Current Photovoltaic Research
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• v.5 no.4
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• pp.140-144
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• 2017

$CuSbS_2$ (CAS) and $CuSbSe_2$ (CASe) nanocrystals (NCs), which consist of earth-abundant elements, were synthesized by a mechanochemical method. Elemental precursors such as copper, antimony, sulfur, and selenium were used without adding any organic solvents or additives. The NCs were synthesized by milling for a few hours. The sudden phase changes occurred by self-ignition and propagation, as previously observed in other mechanochemical synthetic processes. The XRD, Raman, and TEM analysis were carried out to determine the crystallinity and secondary phase of the as-synthesized CAS and CASe NCs, confirming the phase-pure synthesis of CAS and CASe. Optical properties were investigated by UV-Vis spectroscopy and it was observed that the band gap energies were about 1.1 and 1.5 eV, respectively for CAS and CASe, suggesting the potential for the use as solar cell materials. The NC colloids dispersed in anhydrous ethanol were prepared and coated on Mo substrates by a facile doctor-blade method. The investigation on the solar cell properties of the as-synthesized materials is underway.

• The Korean Journal of Emergency Medical Services
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• v.26 no.1
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• pp.7-19
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• 2022

Purpose: The purpose of this study is to evaluate the interrupted chest compression time during the use of an automated external defibrillator (AED) depending on different AED practice training methods, and to report differences in self-efficacy before and after training. Methods: We enrolled university freshmen who have had cardiopulmonary resuscitation (CPR) training but have not or have had AED training but over 6 months. We examined differences between the group that practiced only shockable rhythms during training and the group that practiced both shockable and non-shockable rhythms. Results: A total of 72 individuals participated in this study, with 36 individuals each in the control and experimental groups. There was no statistically significant difference in the proficiency of AED usage between the two groups. In non-shockable cases, the experimental group showed shorter chest compression interruption time than the control group (2.30±1.21sec vs. 3.16±1.73 sec; p<0.01). In terms of self-efficacy before and after training, both groups showed higher self-efficacy after than before training. Conclusion: Individuals who underwent training that provided practice on both shockable and non-shockable rhythms had a shorter interrupted chest compression time when using the AED.

• Journal of the Korean Electrochemical Society
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• v.4 no.4
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• pp.139-145
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• 2001

Various compositions of iron oxide based materials as a cathode of lithium secondary battery have been fabricated and tested with electrochemical method. A layered form of $LiFeO_2$ was synthesized by mixing and heating the initial materials of $FeCl_3\;6H_2O,\;LiOH$ and NaOH at low temperature. The effect of changing the precursors composition was investigated. As a result, when increasing the additive amount of NaOH, the capacity of the electrode is decreased but the performance and declining rate of capacity became smaller. $LiFeO_2$ synthesized with the weight ratio of $NaOH/FeCl_3/LiOH,\;2/1/7$ showed the largest capacity, but the discharging efficiency was sharply decreased after 30 cycles. Charge-discharge tests of lithium cells with $LiFeO_2$ cathode having the layer structure were performed. This cell showed the reversibility in the range of 1.5-4.5V of cell voltage. By using CPR method, chemical diffusion coefficients were measured in 1M $LiPF_6/EC/DEC$ solution. The value of chemical diffusion coefficient decreased with increasing the lithium content x, In 0.5$10^{-11}^cm^2/s$.