• International Journal of Arrhythmia
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• 제18권2호
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• pp.66-76
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• 2017

Background and Objectives: Although an anterior linear ablation is an effective lesion set in radiofrequency catheter ablation (RFCA) for longstanding persistent atrial fibrillation (L-PeAF), its durability for bidirectional block (BDB) is only about 60% at repeat procedure. We hypothesized that changes in electrocardiogram (ECG) may predict an anterior line block state and the clinical outcome of L-PeAF ablation. Subjects and Methods: We studied 304 L-PeAF patients (77% male, $60{\pm}10yrs$), who consistently underwent RFCA Dallas lesion set (circumferential pulmonary vein isolation, posterior box lesion, and anterior line) protocol with subsequent comparison of pre-procedural and post-procedural P wave axes, and one year follow-up (n=205) sinus rhythm (SR) ECGs. Results: 1. P wave axis shifted inferiorly at immediate post-procedure (p<0.001), and was independently correlated with BDB of anterior line (${\ss}=10.4$, 95% confidence interval [CI] 2.79-17.94, p=0.008). 2. The degree of post-procedural inferior shift of P wave axis did not reflect clinical recurrence within one-year (n=205, p=0.923), potentially due to conduction recovery of an anterior line. However, among 160 patients without clinical recurrence within one-year, P wave axis at one-year ECG was independently associated with very late recurrence of AF after one-year (n=160, hazard ratio [HR] 0.98; 95% CI 0.97-0.99, p=0.001), during $45.6{\pm}16.7$ months of follow-up. 3. Among 22 patients who underwent repeat procedures, P wave axis shift was more significant in patients with maintained BDB of an anterior line than in those without (p=0.015). Conclusion: An inferior shift of P wave axis reflects the achievement and the maintenance of an anterior line BDB, and is associated with better long-term clinical outcome after catheter ablation for L-PeAF based on Dallas lesion set.

• Korean Journal of Materials Research
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• v.30 no.8
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• pp.413-420
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• 2020

Lu₃Al_5-xGa_xO₁₂:Ce³⁺,Cr³⁺ powders are prepared using a solid-state reaction method. To determine the crystal structure, Rietveld refinement is performed. The results indicate that Ga³⁺ ions preferentially occupied tetrahedral rather than octahedral sites. The lattice constant linearly increases, obeying Vegard's law, despite the strong preference of Ga³⁺ for the tetrahedral sites. Increasing x led to a blue-shift of the Ce³⁺ emission band in the green region and a change in the emission intensity. Persistent luminescence is observed from the powders prepared with x = 2-3, occurring through a trapping and detrapping process between Ce³⁺ and Cr³⁺ ions. The longest persistent luminescence is achieved for x = 2; its lifetime is at least 30 min. The findings are explained using crystal structure refinement, crystal field splitting, optical band gap, and electron trapping mechanism.

• Korean Journal of Materials Research
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• v.13 no.10
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• pp.673-676
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• 2003

We have investigated $Al_{x}$ $Ga_{l-x}$ N/GaN epilayers (x = 0.08, 0.15) grown by metal organic vapor phase epitaxy on sapphire with photoluminescence(PL), and persistent photoconductivity(PPC) experiments. An anomalous S-shaped shift behavior of temperature dependencies of PL peak energy is observed for the x = 0.15 sample. In PPC measurement, showed that the dark current recovery time of $Al_{x}$$Ga_{l-x}$ N/GaN epilayers mainly depends on the Al content. These behaviors are usually attributed to the presence of carrier localization states. All these phenomena are explained based on the alloy compositional fluctuations in the $Al_{x}$ /$Ga_{l-x}$ N/ epilayers. The photocurrent quenching observed in PPC measurements for $Al_{x}$ $Ga_{l-x}$ N/ epilayers less than 0.2 $\mu\textrm{m}$ thickness indicates that the presence of metastable state in the bandgap of GaN layer, and that the excess holes in the valence band recombine with free electrons.

• JSTS:Journal of Semiconductor Technology and Science
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• v.2 no.3
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• pp.170-172
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• 2002

The epilayer of vertically stacked, self-assembled InAs Quantum Dots (QDs)was grown by MBE with solid sources in non-cracking K-cells, and the sample was fabricated to a FET structure using a conventional technology. The device characteristic and performance were studied. At 77K and room temperature, the threshold voltage shift values are 0.75V and 0.35 V, which are caused by the trapping and detrapping of electrons in the quantum dots. Discharging and charging curves form the part of a hysteresis loop to exhibit memory function. The electrical injection of confined electrons in QDs products the threshold voltage shift and memory function with the persistent electron trapping, which shows the potential use for a room temperature application.

• Journal of Life Science
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• v.7 no.3
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• pp.161-166
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• 1997

HIV-1 Rev protein plays an important role in regulating the expression of viral structural proteins. It allows the nuclear export and accumulation of unspliced and partially spliced viral mRNA in the cytoplasm. The Rev-responsive element RNA, present in the env gene, forms a higly ordered RNA secondary structure and is required for the Rev-mediated mRNA export. For this process to complete factor(s) are strongly suggested. From our experiments of electrophoretic mobility shift, UV-crosslinking and SDS/PAGE, RRE RNA was found to be recognized to several nuclear factors such as 36/37, 56, 41. 76, 150 kD proteins in the order of reactivity. Among them, 36/37 and 56 kD proteins are more reactive upon a brief UV treatment (5 min) and more persistent in the presence of high amount of nonspecific competitor, heparin. Certain nuclear protein9s) seemed to recognize the RRE RNA structure in competition with Rev to gel mobility shift assay.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.662-671
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• 2020

It is crucial to manage and maintain the geodetic reference coordinates of GNSS continuously operating reference stations (CORSs) in consideration of their fundamental roles in geodetic control and positioning navigation infrastructure. Earthquake-induced crustal displacement directly impacts the reference coordinates, so such events should be promptly detected, and appropriate action should be made to maintain the target accuracy, including update of the geodetic coordinates. To this end, this paper deals with online schemes for the detection of persistent shifts in the coordinate time-series produced by an automatic GNSS processing system. Algorithms were implemented to test filtered results, such as hypothesis tests of the innovation sequence of a Kalman filter and a cumulative sum (CUSUM) test. The results were assessed by the time-series of coordinates of 14 CORS for two years, including the 2011 Tohoku earthquake. The results show that the global hypothesis test is practical for detecting abrupt jumps, whereas CUSUM is effective for identifying persistent shifts.

• Journal of Microbiology and Biotechnology
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• v.31 no.10
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• pp.1350-1357
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• 2021

Staphylococcus aureus (S. aureus) is a major pathogen that causes human pneumonia, leading to significant morbidity and mortality. S. aureus coagulase (Coa) triggers the polymerization of fibrin by activating host prothrombin, which then converts fibrinogen to fibrin and contributes to S. aureus pathogenesis and persistent infection. In our research, we demonstrate that isovitexin, an active traditional Chinese medicine component, can inhibit the coagulase activity of Coa but does not interfere with the growth of S. aureus. Furthermore, we show through thermal shift and fluorescence quenching assays that isovitexin directly binds to Coa. Dynamic simulation and structure-activity relationship analyses suggest that V191 and P268 are key amino acid residues responsible for the binding of isovitexin to Coa. Taken together, these data indicate that isovitexin is a direct Coa inhibitor and a promising candidate for drug development against S. aureus infection.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.125.1-125.1
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• 2012

The wave number 4 (wave-4) and wave number 3 (wave-3) longitudinal structures in the thermospheric neutral mass density are understood as tidal structures driven by diurnal eastward-propagating zonal wave number 3 (DE3) and wave number 2 (DE2) tides, respectively. However, those structures have been identified using data from limited time periods, and the consistency and recurrence of those structures have not yet been examined using long-term observation data. We examine the persistence of those structures by analyzing the neutral mass density data for the years 2001-2008 taken by the CHAllenging Minisatellite Payload (CHAMP) satellite. During years of low solar activity, the amplitude of the wave-4 structure is pronounced during August and September, and the wave-4 phase shows a consistent eastward phase progression of $90^{\circ}$ within 24 h local time in different months and years. During years of high solar activity, the wave-4 amplitude is small and does not show a distinctive annual pattern, but the tendency of the eastward phase shift at a rate of $90^{\circ}$/24 h exists. Thus the DE3 signature in the wave-4 structure is considered as a persistent feature. The wave-3 structure is a weak feature in most months and years. The amplitude and phase of the wave-3 structure do not show a notable solar cycle dependence. Among the contributing tidal modes to the wave-3 structure, the DE2 amplitude is most pronounced. This result may suggest that the DE2 signature, although it is a weak signature, is a perceivable persistent feature in the thermosphere.

• The Korean Journal of Physiology
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• v.6 no.2
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• pp.1-8
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• 1972

A study was planned to see if the mammillary bodies have any influence upon orienting response Thirty-nine male rats were divided into two groups. One group of animals received electrolytic lesion of the mammillary bodies through stereotaxically implanted electrodes (mammillary body group), and the other group received the same treatment short of electrolytic lesion(operated control group). All animals were tested for orienting response 3 weeks after surgery. Orienting response was regarded as elicited when an animal in alertness ceased ongoing activity upon 1,000 Hz tone presentation and/or turned head toward the source of stimulus. Weak (momentary and inconspicuous) and strong (marked and more persistent) responses were discriminated. Occurrence and duration of orienting response were measured, and the rate of habituation was estimated in 20 trials. Shift of attention from sound to light stimulus (10 trials) as well as orienting response of thirsty animals to sound stimulus while drinking (5 trials) and while at rest (5 trials) were also tested. 1. Simple orienting respons to sound stimulus tended to occur more often and its duration tended to be shorter in the mammillary body group than in the operated control group. 2. With repetition of trials, the occurrence of orienting response in each trial decreased progressively in both groups (habituation). However, the rate of habituation was significantly less prominent in the mammillary body group than in the operated control group. 3. Under attention·shift situation, orienting response tended to occur less often and its duration tended to be shorter in the mammillary body group than in the operated control group. 4. Orienting response to sound stimulus while drinking to quench thirst tended to occur more often and its duration tended to be shorter in the mammillary body group than in the operated control group. In quiet state, however, there existed no group difference with regard to the occurrence and duration of the orienting response. Although no obvious inference can be drawn from the above results, they may suggest the mammillary bodies being involved in the orienting response as a control mechanism inhibitory to the occurrence and facilitatory to the habituation of the response.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.1
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• pp.94-100
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• 2006

Computing paradigm shift to internet-based one has accelerated the use of XML in diverse applications. This phenomena has made the explosive increases of XML data and it triggered many active researches in maintaining very huge amount of XML data in turn. In this paper we present a persistent graph-based XML indexing lot data-centric XML data. In our approach we use 3 graphs to represent XML indexes and XML data itself. They are schema graph, data graph index. And then we have mapped those graphs to B+-trees the persistency. With our approach we can achieve linear query execution time with the increase of XML sizes.