• Journal of Korea Soil Environment Society
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• v.2 no.2
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• pp.81-94
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• 1997

In many solute transport studies, either flux or resident concentration has been used. Choice of the concentration mode was dependent on the monitoring device in solute displacement experiments. It has been accepted that no priority exists in the selection of concentration mode in the study of solute transport. It would be questionable, however, to accept the equivalency in the solute transport parameters between flux and resident concentrations in structured soils exhibiting preferential movement of solute. In this study, we investigate how they differ in the monitored breakthrough curves (BTCs) and transport parameters for a given boundary and flow condition by performing solute displacement experiments on a number of undisturbed soil columns. Both flux and resident concentrations have been simultaneously obtained by monitoring the effluent and resistance of the horizontally-positioned TDR probes. Two different solute transport models namely, convection-dispersion equation (CDE) and convective lognormal transfer function (CLT) models, were fitted to the observed breakthrough data in order to quantify the difference between two concentration modes. The study reveals that soil columns having relatively high flux densities exhibited great differences in the degree of peak concentration and travel time of peak between flux and resident concentrations. The peak concentration in flux mode was several times higher than that in resident one. Accordingly, the estimated parameters of flux mode differed greatly from those of resident mode and the difference was more pronounced in CDE than CLT model. Especially in CDE model, the parameters of flux mode were much higher than those of resident mode. This was mainly due to the bypassing of solute through soil macropores and failure of the equilibrium CDE model to adequate description of solute transport in studied soils. In the domain of the relationship between the ratio of hydrodynamic dispersion to molecular diffusion and the peclet number, both concentrations fall on a zone of predominant mechanical dispersion. However, it appears that more molecular diffusion contributes to the solute spreading in the matrix region than the macropore region due to the nonliearity present in the pore water velocity and dispersion coefficient relationship.

• Tuberculosis and Respiratory Diseases
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• v.61 no.3
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• pp.265-272
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• 2006

Background: Chest wall deformities such as kyphoscoliosis, thoracoplasty, and fibrothorax cause ventilatory insufficiency that can lead to chronic respiratory failure, with recurrent fatal acute respiratory failure(ARF). This study evaluated the frequency and outcome of ARF, the physiologic status, and the long-term prognosis of these patients. Methods: Twenty-nine patients with chest wall disorders, who experienced the first requirement of ventilatory support from ARF were examined. The mortality and recurrence rate of ARF, the pulmonary functions with arterial blood gas analysis, the efficacy of home oxygen therapy, and the long-term survival rate were investigated. Results: 1) The mortality of the first ARF was 24.1%. ARF recurred more than once in 72.7% of the remaining 22 patients, and overall rate of successful weaning was 73.2%. 2) Twenty-two patients who recovered from the first ARF showed a restrictive ventilatory impairment with a mean FVC and TLC of 37.2% and 62.4 % of predicted value, respectively, and a mean $PaCO_{2}$ of 57mmHg. Among the parameters of pulmonaty functions. the FVC(p=0.01) and VC(p=0.02) showed a significant correlation with the $PaCO_{2}$ level. 3) There were no significant differences between the patients treated with conservative medical treatment only and those with additional home oxygen therapy due to significant hypoxemia in the patients with recurrent ARF and the mortality. 4) The 1, 3, 5-year survival rates were 75%, 66%, and 57%, respectively, in the 20 patients who had recovered from the first ARF, excluding the two patients managed by non-invasive nocturnal ventilatory support. Conclusion: These results suggest that active ventilatory support should be provided to patients with ARF and chest wall disorders. However, considering recurrent ARF and weak effect of home oxygen therapy, non-invasive domiciliary ventilation is recommended in those patients with these conditions to achieve a better long-term prognosis.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.1
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• pp.83-93
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• 1997

Although IVF-ET is widely applied in the treatment of couples with male factor infertility, it may fail in many infertile couples with normal semen parameters, and certain couples cannot be accepted for standard IVF-ET due to unfertilization or extremely low fertilization rate of oocytes. Recently, several procedures of microassisted fertilization (MAF) using micromanipulation have been introduced, and pregnancies and births have been obtained after partial zona dissection (PZD), subzonal insertion (SUZI), and intracytoplasmic sperm injection (ICSI). This clinical study was performed to develop and establish ICSI as an effective procedure of MAF in infertile couples who could not undergo standard IVF-ET repetitively because of failure in fertilization or extremely low fertilization rate of oocytes with the conventional fertilization technique in the previous IVF-ET cycles. From March, 1995 to May, 1996, 27 cycles of IVF-ET with ICSI in 19 infertile patients were included in study group, and the outcomes of ICSI were analyzed according to fertilization rate, cumulative embryo score (CES), and pregnancy rate. The number of oocytes retrieved after controlled ovarian hyperstimulation (COH) was $10.50{\pm}6.13$ in 30 previous cycles, and $10.57{\pm}5.53$ in 27 ICSI cycles. In ICSI cycles, the number of oocytes optimal for ICSI procedure was $7.89{\pm}4.30$, and the fertilization rate of $67.9{\pm}20.2%$ could be obtained after ICSI. The number of embryos transferred was $1.43{\pm}2.40$ in previous cycles, and $4.36{\pm}1.77$ with the mean CES of $41.8{\pm}27.4$ in ICSI cycles. In ICSI cycles, the overall pregnancy rate was 29.6% (8/27) per cycle and 42.1% (8/19) per patient with the clinical pregnancy rate of 22.2% (6/27) per cycle and 31.6% (6/19) per patient. In conclusion, MAF of human oocytes with ICSI is a promising fertilization method for IVF-ET patients, especially with the past history of failure in fertilization or low fertilization rate of oocytes in the previous IVF-ET cycles, and ICSI using micromanipulation procedures applied to human oocytes will provide a range of novel techniques which may dramatically improve the pregnancy rate in IVF-ET program and contribute much to effective management of infertile couples.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.3
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• pp.193-202
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• 2008

Objective: To evaluate efficacy of assisted hatching by laser (AHL) and acidified Tyrode solution (AHA) in selected groups of IVF-ET patients who have a poor prognosis. Methods: From February 2006 to September 2006, total of 328 IVF-ET cycles with advanced female age (${\geq}38$ years), recurrent implantation failure (${\geq}3$ cycles), thick zona (${\geq}17{\mu}m$), and/or poor quality of embryo were randomly divided into assisted hatching by acidified Tyrode solution (AHA, n=180) and the assisted hatching using the ZILOS-tk laser (AHL, n=148) groups. Clinical outcomes were analyzed and compared between AHA and AHL group based on the patient characteristics. Results: In all AHL and AHA group, there were no significant differences in pregnancy (42.6%, 63/148 vs. 33.3%, 60/180) and implantation rates (17.4%, 82/470 vs. 16.0%, 89/556) However, in advanced female age group (Group 1), pregnancy (37.0%, 20/54 vs. 18.7%, 14/75) and implantation rates (14.4%, 23/160 vs. 7.1%, 15/210) in AHL group were significantly (p<0.05) higher than those of AHA, although there was no difference in patient parameters of both groups. And, the clinical outcome of groups with recurrent implantation failure (Group 2), thick zona pellucida (Group 3) and poor quality embryo (Group 4) were improved in AHL compared to those of AHA: 43.8% (21/48) and 31.6% (25/79) in Group 2, 43.8% (32/73) and 34.1% (28/82) in Group 3, 25.0% (7/28) and 14.6% (6/41) in Group 4, but no significance. Conclusion: The AHL improved the pregnancy and implantation rates in patients with advanced female age and recurrent implantation failure when compared to outcomes achieved from AHA. Therefore, this AHL technique may be a efficient and safe method for patients with poor prognosis.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.4
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• pp.305-312
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• 2007

Objective: To evaluate the efficacy of split insemination method in treatments for non-male factor infertility. Method: Laboratory and clinical data were collected from 505 cycles of split insemination during 2002$\sim$2005 in our center. The subjects were non-male factor infertility such as endometriosis, tubal, uterine, PCOS and idiopathic infertility without any sperm defects. Retrieved oocytes were randomly divided, and inseminated by conventional IVF or ICSI. Fertilized zygotes were cultured for 2$\sim$5 days to ET date, and surplus zygotes and embryos were frozen for subsequent frozen-thawed ET cycles. Clinical outcomes according to insemination method were compared by statistical analysis. Results: The overall fertilization per retrieved oocytes was significantly higher in ICSI than that of conventional IVF in sibling oocytes (62.5$\pm$22.3% vs 52.9$\pm$28.0%, p<0.01). Total fertilization failure occurred only in 2 of 505 cycles (0.4%) in split insemination cycles. Incidence of fertilization failure and poor fertilization rate less than 30% by ICSI were significantly lower than those of conventional IVF (1.1% and 7.5% vs 8.5% and 22.0%, p<0.01). Delivery rates after transfer of fresh and thawed embryos from split insemination cycles were 40.0% (185/462) and 35.0% (55/157), respectively. There was no significant difference in the implantation and delivery rates of ET with embryos from conventional IVF or ICSI. Conclusion: Taken together, the split insemination method improves poor fertilization rates resulting in successful clinical outcomes and thus could be used for non-male factor infertile couples in human ART program.

• The korean journal of orthodontics
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• v.37 no.3 s.122
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• pp.171-181
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• 2007

Objective: The present study was aimed at an analytical formulation of the micro-implant related torque as a function of implant size, i.e. the diameter and length, screw size, and the bony resistance at the implant to bone interface. Methods: The resistance at the implant to cancellous bone interface $(S_{can})$ was assumed to be in the range of 1.0-2.5 MPa. Micro-implant model of Absoanchor (Dentos Inc. Daegu, Korea) was used in the course of the analysis. Results: The results showed that the torque was a strong function of diameter, length, and the screw height. As the diameter increased and as the screw size decreased, the torque index decreased. However the strength index was a different function of the implant and bone factors. The whole Absoanchor implant models were within the safe region when the resistance at the implant/cancellous bone $(=S_{can})$ was 1.0 or less. Conclusion: For bone with $S_{can}$ of 1.5 MPa, the cervical diameter should be greater than 1.5 mm if micro-implant models of 12 mm long are to be placed. For $S_{can}$ of 2.0 MPa, micro-implant models of larger cervical diameter than 1.5 mm were found to be safe only if the endosseous length was less than 8 mm.

• Journal of Life Science
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• v.28 no.2
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• pp.240-246
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• 2018

Efferent and afferent sympathetic nerves are closely related to the development of hypertension and heart failure. Catheter-based renal sympathetic denervation (RDN) is implemented as a strategy to treat resistant hypertension. We investigated whether RDN procedure causes inflammatory damage on myocardium in the early phase of sympathetic denervation. Twenty-five female swine were divided into 3 groups: normal control (Normal, n=5), sham-operated control (Sham, n=5), and RDN groups (RDN, n=15). The RDN group was further subdivided into 3 subgroups according to the time of sacrifice: immediately (RDN-0, n=5), 1 week (RDN-1, n=5), and 2 weeks (RDN-2, n=5) after RDN. There were no significant changes in the clinical parameters between the normal control and sham-operated group using contrast-media. In the myocardium, inflammatory cytokines, $IL-1{\beta}$ and $TNF-{\alpha}$ increased at the first week, and then decreased at the second week after RDN. Anti-inflammatory cytokine, IL-10 increased immediately, and then decreased at the second week after RDN. Caspase-1 activity and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) expression increased immediately after RDN until the second week. However, nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing protein 3 (NLRP3) expression did not show any significant differences among the groups. The RDN can cause acute myocardial inflammation through activation of caspase-1 and $IL-1{\beta}$. We should pay attention to protecting against early inflammatory myocardial damage after RDN.

• Clinical and Experimental Reproductive Medicine
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• v.36 no.4
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• pp.275-281
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• 2009

Objective: This study was performed to evaluate the effect of oxytocin antagonist on the outcome of IVF/ICSI cycles in infertile patients with repeated failure of IVF/ICSI treatment. Method: Forty patients who had experienced two or more failures of IVF/ICSI treatment without low ovarian reserve, were recruited for this prospective randomized study. All patients received controlled ovarian stimulation (COS) using GnRH antagonist multidose protocol (MDP). For the intervention group, intravenous administration of atosiban (mixed vasopressin $V_{1A}$/oxytocin antagonist) started with a bolus dose 6.75 mg one hour before embryo transfer (ET) and continued at an infusion rate of 18 mg/hour. After ET, administered atosiban was reduced to 6 mg/hour and continued for 2 hours. The main efficacy endpoints were clinical pregnancy rate and implantation rate. Results: Patients' characteristics were comparable in the intervention and control groups. COS parameters and IVF results were also similar. The number of uterine contractions for 3 minutes measured just before ET was significantly lower in the intervention group than control group ($3.5{\pm}1.4$ vs $8.7{\pm}2.2$, p<0.001). While there was no statistically significant difference in the clinical pregnancy rate between control group and intervention group (20.0% and 40.0%, p=0.168), the implantation rate was significantly higher in the intervention group, with 16.9% (11/65) compared with 6.0% (4/67) in the control group (p=0.047). There were no differences in ectopic pregnancy rate and miscarriage rate between the two groups. Conclusion: This study demonstrates that administration of oxytocin antagonist during ET can improve the implantation rate probably by decreasing the frequency of uterine contractions in infertile patients undergoing IVF/ICSI treatment.

• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.515-525
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• 2007

In this investigation, results of laboratory tests on four reinforced concrete flat plate interior connections with elongated rectangular column support which has been used widely in tall residential buildings are presented. The purpose of this study is to evaluate an effect of column aspect ratio (${\beta}_c={c_1}/{c_2}$=side length ratio of column section in the direction of lateral loading $(c_1)$ to the direction of perpendicular to $c_1$) on the hysteretic behavior under earthquake type loading. The aspect ratio of column section was taken as $0.5{\sim}3\;(c_1/c_2=1/2,\;1/1,\;2/1,\;3/1)$ and the column perimeter was held constant at 1200mm in order to achieve nominal vertical shear strength $(V_c)$ uniformly. Other design parameters such as flexural reinforcement ratio $(\rho)$ of the slab and concrete strength$(f_{ck})$ was kept constant as ${\rho}=1.0%$ and $f_{ck}=40MPa$, respectively. Gravity shear load $(V_g)$ was applied by 30 percent of nominal vertical shear strength $(0.3V_o)$ of the specimen. Experimental observations on punching failure pattern, peak lateral-load and story drift ratio at punching failure, stiffness degradation and energy dissipation in the hysteresis loop, and steel and concrete strain distributions near the column support were examined and discussed in accordance with different column aspect ratio. Eccentric shear stress model of ACI 318-05 was evaluated with experimental results. A fraction of transferring moment by shear and flexure in the design code was analyzed based on the test results.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1811-1815
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• 2014

Background: In clinical trials with no upper age limit, the proportion of older patients is usually small, probably reflecting the more conservative approach adopted by clinicians when treating the elderly. An exploratory analysis of elderly patients in the RECORD-1 Trial showed that patients ${\geq}$ 65 y.o. had superior median PFS than overall RECORD-1 population (5.4 months and 4.9 months, respectively). We investigated the efficacy, relative benefit and safety of Everolimus (EVE) as sequential therapy after failure of VEGFr-TKI therapy for older patients with metastatic renal cell cancer (mRCC), in daily practice. Materials and Methods: 172 consecutive IRB approved patients with mRCC (median age 65, M:F 135/37, 78% clear cell) who received salvage EVE at 39 tertiary institutions between October 2009 and August 2011 were included in this analysis. Some 31% had progressed on sunitinib, 22% on sorafenib, 1% on axitinib, 41% on sequential therapy, and 5% had received other therapy. Patients with brain metastases were not included and 95% of the patients had a ECOG (Eastern Cooperative Oncology Group) performance status (PS) of 0 or 1. Previous radiotherapy was an exclusion criterion, but prior chemotherapy was permitted. Adequate organ function and hematologic parameters were mandatory. EVE administration was approved by the institutional review board at each participating institution and signed informed consent was obtained from all patients. Results: Median time of the whole cohort to last follow-up was 3.5 months (range 0.4-15.2 months). Forty four percent were continuing to take EVE at last followup. There were 86 (50%) patients ${\geq}$ 65 y.o. and 86 (50%) <65 y.o. The percentage of patients who showed PR/SD was higher in the older group than in the younger one (5.9%/61.2% vs 1.2%/46.5%, respectively). Median survival of older patients was also significantly longer (3.5 +/- 0.31 vs 3.1 +/- 0.34, hazard ratio=0.45, CI; 0.255-0.802). Analysis using Cox regression model adjusted for gender, PS, number of metastases, site of metastases, histology, smoking history and age detected an association between age and PFS (p=0.011). The frequency of adverse events in elderly patients treated with EVE was no greater than that in younger patients, although such toxicity may have had a greater impact on their quality of life. Conclusions: Older patients should not generally be excluded from accepted therapies (mTOR inhibitors after failure of VEGFr-TKI therapy) for mRCC.