• The Korean Journal of Physiology
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• v.23 no.2
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• pp.313-328
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• 1989

The electrophysiological properties of the inward current contributing to the late plateau phase of the action potential were investigated using the whole cell clamp technique and intracellular dialysis in single atrial cells isolated from the rabbit heart. The inward current was activated by various repolarizing pulses after a brief depolarizing pulse to +40 mV for 2 ms and its time course was similar to that of the late plateau of the action potential. The current was fully activated above the potential of -40 mV and abolished by intracellular EGTA. Ryanodine of $1{\mu}M$ also abolished the late plateau and the inward current. Reduced $Na_o\;to\;30%\;and\;20\;mM\;Na_1$ diminished the late plateau together with the inward current. Diltiazem blocked the activation of the current and Ni in the concentration of $40{\sim}200\;{\mu}M$ decreased the development of the late plateau and the inward current. Fully activated current-voltage relation of the inward current showed exponential voltage dependency which was steeper in more hyperplarizing range. The above findings suggest that the inward current was activated by intracellular calcium and contribute the late plateau phase of the action potential. It could be concluded that the inward current would be the inward component of Na-Ca exchange.

• The Journal of Korean Physical Therapy
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• v.10 no.1
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• pp.199-212
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• 1998

The purpose of this article is to summary about the application of electromyography and nerve conduction study. Electrodiagnostic studies, which include nerve conduction studies, electromyography, repetitive nerve stimulation, single fiber EMG, late response tests and evoked potential tests are a critical component of the neuromuscular evaluation.

• Journal of Korean Physical Therapy Science
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• v.5 no.2
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• pp.603-616
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• 1998

The purpose of this article is to summary about the application of electromyography and nerve conduction study. Electrodiagnostic studies, which include nerve conduction studies, electromyography, repetitive nerve stimulation, single fiber EMG, late response tests and evoked potential tests are a critical component of the neuromuscular evaluation.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.24-24
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• 2019

This study investigates variations in the Western Pacific Subtropical High (WPSH) and its impact on South Korean precipitation in late summer during the period between 1958 and 2017. Composite analysis reveals that precipitation occurrence is directly linked to the displacement of the WPSH western ridge, a single, large-scale feature of the atmosphere in the Pacific Ocean. When WPSH ridging is located northwest (NW) of its climatological mean position, excessive precipitation is expected in late summer due to enhanced moisture transport. On the other hand, a precipitation deficit is frequently observed when the western ridge is located in the southeast (SE). Different phases of the WPSH are associated with lagged patterns of Pacific and Atlantic atmospheric and oceanic variability, introducing the potential to predict variability in the WPSH western ridge and its climate over northern East Asia by one month. Based on the identified SST patterns, a simple statistical model is developed and improvement in the ability to predict is confirmed through a cross-validation framework. Finally, the potential for further improvements in WPSH-based predictions is addressed.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.4
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• pp.362-367
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• 2021

Objective: The impact of early mechanical removal of cumulus cells on fertilization and embryonic development is not yet precisely known. This study aimed to investigate the effects of early and late cumulus cell removal on fertilization, polyspermy, embryonic development potential, blastocyst development, and clinical outcomes. Methods: A prospective study was conducted of patients who underwent in vitro fertilization between September 2019 and October 2020. Sibling oocytes were randomly allocated after insemination to early cumulus cell removal at 6 hours (group I) and late cumulus cell removal at 16-18 hours (group II). If total fertilization failure (TFF) was determined to have occurred at early cumulus cell removal, rescue intracytoplasmic sperm injection (ICSI) was performed. Fertilization, embryonic development, and pregnancy outcomes were compared. Results: A total of 912 oocytes were assigned to group I (458 oocytes) and group II (454 oocytes). Fertilization, polyspermy, embryo quality, and pregnancy outcomes were not significantly different between both groups. Rescue ICSI enabled fertilization of 79.2% of the TFF oocytes. Conclusion: Early cumulus cell removal at 6 hours had no significant difference in fertilization, polyspermy, embryo development, or obstetric and perinatal outcomes compared to late removal. Early cumulus cell removal combined with early rescue ICSI may have the potential to help couples with TFF.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3241-3251
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• 2023

The potential for recriticality and sub-critical boron concentrations is analyzed during the relocation of the fuel rods in the assembly, which we call late phase of a severe accident, via coupling between MELCOR and whole-core Monte Carlo analyses by Serpent 2. The recriticality, initiated during the early phase, is found to maintain when the fuel assemblies containing intact fuel rods are submerged by the cooling water. It is also found that the effect of the negative reactivity insertion via remaining fission products in the fuel debris increases as the burnup increases. The sub-critical boron concentrations during the late phase are found to be 76~544 ppm lower than those during the early phase. Therefore, it can be concluded that the boron concentration that prevents recriticality not only during the early phase but also during the late phase is the sub-critical boron concentration during the early phase.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.316-326
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• 2014

Determination of the late marginal heading date (LMHD), which would allow estimation of the late marginal seeding date and the late marginal transplanting date, would help identification of potential double cropping areas and, as a result, establishment of cropping systems. The objective of this study was to determine the LMHD at 51 sites in Korea. For these sites, weather data were obtained from 1971 to 2000 and from 1981 to 2010, which represent past and current normal climate conditions, respectively. To examine crop productivity on the LMHD, climatic yield potential (CYP) was determined to represent the potential yield under a given climate condition. The LMHD was calculated using accumulated temperature for 40 days with threshold values of $760^{\circ}C$, $800^{\circ}C$, $840^{\circ}C$ and $880^{\circ}C$. The value of CYP on a given LMHD was determined using mean temperature and sunshine duration for 40 days from the LMHD. The value of CYP on the LMHD was divided by the maximum value of CYP (CYPmax) in a season to represent the relative yield on the LMHD compared with the potential yield in the season. Our results indicated that the LMHD was delayed at most sites under current normal conditions compared with past conditions. Spatial variation of the LMHD differed by the threshold temperature. Overall, the minimum value of CYP/CYPmax was 81.8% under all of given conditions. In most cases, the value of CYP/CYPmax was >90%, which suggested that yield could be comparable to the potential yield even though heading would have occurred on the LMHD. When the LMHD could be scheduled later without considerable reduction in yield, the late marginal transplanting date could also be delayed accordingly, which would facilitate doublecropping in many areas in Korea. Yield could be affected by sudden change of temperature during a grain filling period. Yet, CYP was calculated using mean temperature and sunshine duration for 40 days after heading. Thus, the value of CYP/CYPmax may not represent actual yield potential due to change of the LMHD, which suggested that further study would be merited to take into account the effect of weather events during grain filling periods on yield using crop growth model and field experiments.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.342-345
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• 2001

Telecommunication services are distinctive in that their adoptions are influenced by network effect resulting in 'the late take-off Phenomenon' and the 'critical mass' problem. In this paper we examined, so called, 'the late take-off phenomenon' in the diffusion process of telecommunication services. We compared the parameters of the diffusion process of consumer durables with those of fax services in the US and Korea. By analyzing the parameters of a new diffusion model based on the threshold model proposed by Markus, We found that 'the late take-off phenomenon' resulted from the low heterogeneity of the threshold distribution for the potential adopters.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.2
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• pp.81-96
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• 2002

Telecommunication services are distinctive in that their adoptions are influenced by network effect resulting in 'the late take-off phenomenon' and the 'critical mass' problem. In this paper we examined, so called, 'the late take-off phenomenon' in the diffusion process of telecommunication services. We compared the parameters of the diffusion process of consumer durables with those of fax services in the US and Korea. By analyzing the parameters of a new diffusion model based on the threshold model proposed by Markus, we found that 'the late take-off phenomenon' resulted from the low heterogeneity of the threshold distribution for the potential adopters. A simulation approach was proposed for the theoretical implication of the 'critical mass' problem in the start-up telecommunications services.

• Archives of Plastic Surgery
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• v.49 no.5
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• pp.611-613
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• 2022

The coronavirus disease 2019 (COVID-19) pandemic has been challenging in all aspects of the medical field with new clinical presentations constantly arising. Plastic surgeons are not immune to this and need to be aware of their implications. There has been a recent report of late periprosthetic seroma (breast implant) as a clinical manifestation of COVID-19 infection. To our knowledge, this phenomenon has not been further reported. We present a 53-year-old immunocompromised lady who developed late seroma after COVID-19 infection. She eventually required explantation of the implant and is awaiting autologous reconstruction. It is likely that we will increasingly continue to see this phenomenon of implant complications as a result of COVID-19 infection and should be watchful, especially regarding potential immunocompromised patients.