• Clinical and Experimental Reproductive Medicine
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• v.25 no.2
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• pp.123-128
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• 1998

Implantation rates remain low following human in vitro fertilization (IVF). Suboptimal culture conditions may limit the ability of embryos to hatch as blastocysts, and artificial opening of the zona pellucida has been proposed as a means to promote subsequent hatching (assisted hatching). In this study, assisted hatching (AH) by zona drilling using acidic Tyrode's solution was performed in 320 patients, due to their age of more than 38 years (group A), the thick zona pellucida (group Z; $ZP\geq0.18{\mu}m$), and failures in implantation more than 3 times in previous IVF-ET trial (group P). This study was designed firstly, to study the effects of AH on the outcomes of IVF-ET according to the indications and secondly, to verify the appropriate application of AH. The results were as follows; 1. There was no difference in pregnancy rate between AH group (26.6%) and non-AH group (26.5%). 2. Assisted hatching (AH) showed significantly higher pregnancy rate of the patients with thick zona pellucid a than those of the patients with age factor and with the history of repeated implantation failure. But in the patients with age factor only, AH resulted in higher pregnancy rate. 3. Interestingly, the patients with complex factors including zona factor (Z: 33.9%; ZA: 30.4%; ZP: 31.6%; ZAP: 21.4%) showed higher pregnancy rates than other complex factors excluding zona factor (A: 24.4%, P: 0%; AP: 10.8%). From these results, AH is more helpful to the patients with thick zona pellucida rather than patients with older age and/or previous repeated implantation failure.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.3
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• pp.122-125
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• 2013

Objective: The majority of embryo transfers (ETs) to date have been performed on day 3 to reduce the potential risk of developmental arrest of in vitro cultured embryos before ET. Development of sequential media has significantly improved culture conditions and allowed blastocyst transfer on day 5. While day 5 ET provides higher clinical pregnancy outcomes with reduced risks of multiple pregnancies, it still has potential risks of developmental arrest of IVF embryos. The aim of this study was to evaluate the clinical outcomes of day 4 ETs and compare the efficacy of day 4 ET with day 5 ET. Methods: From 2006 to 2009, a total of 747 fresh IVF-ET cycles were retrospectively analyzed (day 4, n=440 or and day 5, n=307). The cycles with any genetic factors were excluded. The rates of matured oocytes, fertilization, good embryos, and clinical pregnancy of the two groups were compared. The chi-square test and t-test were used for statistical analysis. Results: There were no significant differences between the two groups with respect to the mean age of the females and rates of matured oocytes. The pregnancy outcomes of day 4 ET (40.7%) were similar to those of day 5 ET (44.6%). The implantation rate of day 5 ET (24.2%) was significantly higher than that of day 4 ET (18.4%) (p=0.003). Conclusion: Day 4 ET can be chosen to avoid ET cancellation in day 5 ET resulting from suboptimal circumstances in the IVF laboratory, but the decremented quality of embryos for transfer and the decreased pregnancy rate must be taken into consideration.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.383-391
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• 2000

Milk urea nitrogen (MUN) determination is being used an indicator of the protein-energy balance in dairy herds. A faulty balance can be corrected to optimize milk production and animal health. This parameter is regarded as a potential tool to evaluate suboptimal feeding practices and reproductive disorders. Therefore, the purpose of this study was to investigate the response of milk composition by regular feeding analysis and to compared the relationship between MUN and milk protein(MP) and fertility at the insemination period in Holstein dairy cows. Total of 355 artificial insemination (AI) for 150 Holstein cows in the herd were used to examine the relationship between MUN and MP content and conception rate. The AI occured for the cows 50 to 150 day in milk, and MUN and MP concentration were determined using automated infrared procedures. The mean${\pm}$standard deviation of MUN and MP concentration in the herd were $15.6{\pm}2.1mg/dl$ and $3.23{\pm}0.38%$, respectively. MUN contents of bulk milk were increase by elevated crude protein intake. The conception rate was lower in the cows in which the level of MUN was lower than > 8.0mg/dl (10.0%) or > higher than 25mg/dl (15.4%) relative to the cows in MUN content of 12.0~17.9 mg/dl (36.7%) at the time of insemination. Also, lower MP than 3.0% or higher MP than 3.25% were associated with a lower conception rates. Consequently, MUN and MP analyses may be used serve as a monitoring tool of protein and energy nutritional balance to improve reproduction efficiency in Holstein dairy cows.

• Journal of Ginseng Research
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• v.12 no.2
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• pp.158-163
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• 1988

P. ginseng seedlings treated with GA,2,4-D and B-9 (N,N-dimethylsuccinamic acid) were grown under dark. Growth efficiencies ($E_1$ = St/Ro, $E_2$ = St1(Ro-Rt), $E_3$ = (Ro- Rt)/ Ro where St. Ro and Rt are shoot weight, initial root weight and root weight at time 1. respectiv$E_1$y) and other r$E_1$ated factors and their interr$E_1$ationship were investigated. $E_1$ and $E_3$ showed quadratic r$E_1$ation with temperature change while $E_2$ showed negative linear r$E_1$ation. $E_1$ depended on more $E_3$ component than $E_2$ component. The values of $E_2$ and $E_3$ are almost same. $E_2$ was greater than that reported previously suggesting large variation between roots. GA greatly increased $E_2$ and $E_3$ in supraoptimum temperature range while B-9 greatly decreased $E_3$ in all temperature range and $E_2$ in suboptimum range. Shoot weight showed highly significant positive linear corr$E_1$ation with substrate amount in most cases of PGR and temperature and with respiration loss in some cases. Respiration loss showed significant linear corr$E_1$ation positiv$E_1$y with $E_1$ and $E_3$ and negativ$E_1$y with $E_2$ only in suboptimal temperature range.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.7 s.361
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• pp.17-22
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• 2007

OFDM (Orthogonal Frequency Division Multiplexing) is a special case of multicarrier transmission, where a single data stream is transmitted over a number of lower-rate subcarrier. One of the main reasons to use OFDM is to increase robustness against frequency-selective fading or narrowband interference. Unfortunately, an OFDM signal consists of a number of independently modulated subcarriers, which can give a large PAPR (Peak-to-Average Power Ratio) when added up coherently. In this paper, we investigate the performance of a simple PAPR reduction scheme, which requires no change of a receiver structure or no additional information transmission. The approach we employed is clipping in the time and frequency domains. The time-domain clipping is carried out with a predetermined clipping level while the frequency-domain clipping is done within EVM (Error Vector Magnitude). This approach is suboptimal with lower computational complexity compared to the optimal method. This evaluation is carried out on the OFDM system with an nonlinear amplifier. The simulation results demonstrated that the PAPR reduction algorithm is one of ways to reduce the effects of the nonlinear distortion of an HPA (High Power Amplifier).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.2C
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• pp.192-199
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• 2008

In ultra-wideband (UWB) systems, conventionally, the synchronization is to align time phases of a locally generated template and any of multipath components to within an allowable range. However, the synchronization with a low-power multipath component could incur significant performance degradation in receiver operation (e.g., detection) after the synchronization. On the other hand, the synchronization with a high-power multipath component can improve the performance in receiver operation after the synchronization. Generally, the first one among multipath components has the largest power. Thus, the synchronization with the first path component can make better performance than that with low-power component in receiver operation after the synchronization, Based on which, we first propose an optimal decision rule based on a maximum likelihood (ML) approach, and then, develope a simpler suboptimal decision rule for selecting the first path component. Simulation results show that the system has good demodulation performance, which uses new synchronization definition and the proposed decision rules have better performance than that of the conventional decision rule in UWB multipath channels. Between macroblocks in the previous and the current frame. On video samples with high motion and scene change cases, experimental results show that (1) the proposed algorithm adapts the encoded bitstream to limited channel capacity, while existing algorithms abruptly excess the limit bit rate; (2) the proposed algorithm improves picture quality with $0.4{\sim}0.9$dB in average.

• YAKHAK HOEJI
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• v.35 no.3
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• pp.174-181
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• 1991

These experiments were conducted to investigate the effects of glycyrrhizin(GL) and glycyrrhetinic acid(GA) on histamine synthesis, lymphocyte blastogenesis in C57BL/6J mice splenocytes, IL-1 production, $Ca^{2+}$ uptake by macrophage-like P388D$_{1}$ cells and plaque forming cell assay against SRBC. Histamine contents, lymphocyte blastogenesis, IL-1 activity, $Ca^{2+}$ uptake and plaque forming cell were determined by enzyme isotope method, [sup 3/H]-thymidine incorporation, C3H/HeJ mouse thymocytes proliferation, the addition of 5 $\mu$Ci/ml $^{45}$Ca$^{2+}$ to P388D$_{1}$, cell suspension and assay to sheep red blood cell, respectively. Cytotoxicity, which was expressed as 50% mortality, was occurred by the addition of GL(10$^{-3}$M) and GA(10$^{-4}$M). Histamine production in mouse spleen cell culture was significantly increased by the addition of 0.25 $\mu\textrm{g}$/ml of Con A, after 48 hour incubation. Con A dependent T-lymphocyte proliferation was also enhanced by the addition of 0.25 .mu.g/ml of Con A. The effects of GL on histamine contents and T-lymphocyte proliferation were significantly decreased at high dose (10$^{-5}$M), while IL-1 activity was remarkably suppressed by 10$^{-8}$~10$^{-4}$M of GL. $Ca^{2+}$ uptake was not changed, but antibody production was increased by GL(10 mg/kg). GA inhibited histamine contents at 10$^{-9}$~10$^{-7}$ and depressed Con A (0.25 $\mu\textrm{g}$/ml) dependent T-lymphocyte proliferation at 10$^{-7}$~10$^{-5}$M of GA, but increased suboptimal dose (Con A 0.1 $\mu\textrm{g}$/ml) at 10$^{-9}$~10$^{-7}$M of GA. IL-1 activity was suppressed by 10$^{-8}$~10$^{-4}$M of GA and $Ca^{2+}$ uptake was enhanced by 10$^{-9}$~10$^{-6}$ of GA, but antibody production was not changed by GA. From the above results, it is suggested that GL and GA have immuno-regulatory action. GL decreased cell-mediated immune response, and increased humoral immune response at high dose. On the other hand, low dose of GA enhanced cell-mediated immune response, while high doses of GA decreased humoral immune reaction.

• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.479-487
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• 2004

Biopotential signals have been used as command in systems using electrical stimulation of motor nerves to restore movement after an injury to the central nervous system (CNS). In order to use the voluntary EMG (electromyography) among the biopotentials as a control signal for the electrical stimulation of the same muscle for CNS injury patients, it is necessary to remove M-wave of having high magnitude from raw data. We designed an optimal filter for removing the M-wave and preserving the voluntary EMG and showed that the optimal filter is eigen filter. We also proved that the previous method using the prediction error filter(PEF) is a suboptimal filtering in the sense of preserving the voluntary EMG. On basis of the data obtained from a model for M-wave and voluntary EMG and from actual CNS injury patients, with false-positive rate analysis, the proposed adaptive filter showed a very promising performance in comparison with previous method.

• The Korean Journal of Pain
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• v.20 no.1
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• pp.50-53
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• 2007

Background: Continuous epidural catheterization is a popular and effective procedure for postoperative analgesia. However, continuous epidural catheterization has associated complications such as venous puncture, dural puncture, subarachnoid cannulation, suboptimal catheter placement, and paresthesia because the tip of the epidural catheter touches thenerves of the dura in the epidural space. In this study, we compared the incidence of paresthesia in two different lengths of epidural catheter insertion. Methods: One hundred women undergoing gynecologic or orthopedic surgery were enrolled in this prospective, double-blinded, randomized study. All patients were randomly divided into two groups based on the insertion length of the epidural catheter 2 cm (group A) or 4 cm (group B). A Tuohy needle was inserted in the lumbarspinal region with a bevel directed cephalad by use of the median approach, and then the epidural space was confirmed by the loss of resistance technique with air. While the practitioner inserted an epidural catheter into the epidural space, a blind observer checked for paresthesia or withdrawal movement. Results: In 97 included patients, 30.6% of the patients in group A (n = 49) had paresthesia, versus 31.3% in group B (n = 48). Withdrawal movements were represented in 2% and 6% of the patients in group A and group B, respectively. There was no difference in the incidence of paresthesia and withdrawal movement between the two groups. Conclusions: There is no clear relationship for the incidence of catheter-related paresthesia according to the catheter length inserted into the epidural space for epidural analgesia.

• Journal of radiological science and technology
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• v.29 no.2
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• pp.63-69
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• 2006

In diagnostic ultrasound, the quality of image affect to diagnose. To maintain suboptimal imaging uniformly, Quality Assurance of Ultrasound equipment should take periodically. This is article about examination the quality of image in diagnostic ultrasound to understand conditions of probes in hospitals. There is comparative study of convex and linear probes on ultrasound using tissue-mimicking phantom included simulated cysts, echogenic structures. The ultrasonic attenuation coefficient versus frequency of 0.5 dB is representative of normal liver and 0.7 dB is representative of fatty liver condition in ultrasound phantom. There are results of convex probe, 0.5 dB, vertical group, cystic masses, high contrast masses are mostly shown but 0.7 dB, mid level in vertical group, cystic masses and high contrast masses are nearly visible. In linear probe, 0.5 dB, mid level in vertical group, two or four of them are shown in cystic masses and high contrast masses but there are not visible in 11 of cases. 0.7 dB, there are mostly appear under 6 in vertical group, two or four of them show in cystic masses and high contrast masses and there are not shown in 40 of cases, besides. Linear probes in fatty liver condition of ultrasound instrument are not good in the quality of image practically. So there needs to be replace and fix of probes. Actually management of ultrasound probes is inadequate in hospitals. So if there are program of evaluation to check probes periodically in hospitals from establishment of the ultrasound equipment, there will get better image and have a suitable condition of instruments further more.