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Comparisons of sample preparation (acid digestion and microwave digestion) and measurement (inductively coupled plasma mass spectrometry and graphite furnace atomic absorption spectrometry) in the determination of bone lead (골중납 측정의 시료 전처리 (산분해법과 마이크로웨이브 분해법)와 측정 방법 (유도결합 플라즈마 질량분석법과 흑연로 원자 흡수 분광 광도법)의 비교)

  • Yoon, Chungsik;Choi, Inja;Park, Sungkyun;Kim, Rokho
    • Analytical Science and Technology
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    • v.16 no.2
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    • pp.152-158
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    • 2003
  • This study was conducted to evaluate two sample digestion procedures and instrumental determination parameters for analysis of lead in bone. Amputated human legs were treated by acid digestion or microwave dissolution prior to spectrometric analysis. Inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GF-AAS) were used for determining bone lead levels. Recovery efficiencies using standard reference material from acid digestion measured by ICP-MS were in good agreement with those of the certified value, but in cases of acid digestion by GF-AAS and microwave digestion by both two methods, recovery underestimated and overestimated, respectively. For the bone samples, the lead concentrations obtained by ICP-MS after acid digestionwere in good agreement with those by GF-AAS (correlation coefficient = 0.983), but GF-AAS gave systematically higher values than ICP-MS. While a good agreement between two analytical methods after microwave digestion was also obtained (correlation coefficient = 0.950), bone lead concentrations from microwave were relatively higher than those from acid digestion. In conclusion, the use of the simple nitric acid digestion procedure at an ambient temperature coupled to ICP-MS seems to be efficient for the determination of lead in bone in consideration for both the convenience and validity.

Current status and future plans of KMTNet microlensing experiments

  • Chung, Sun-Ju;Gould, Andrew;Jung, Youn Kil;Hwang, Kyu-Ha;Ryu, Yoon-Hyun;Shin, In-Gu;Yee, Jennifer C.;Zhu, Wei;Han, Cheongho;Cha, Sang-Mok;Kim, Dong-Jin;Kim, Hyun-Woo;Kim, Seung-Lee;Lee, Chung-Uk;Lee, Yongseok
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.41.1-41.1
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    • 2018
  • We introduce a current status and future plans of Korea Microlensing Telescope Network (KMTNet) microlensing experiments, which include an observational strategy, pipeline, event-finder, and collaborations with Spitzer. The KMTNet experiments were initiated in 2015. From 2016, KMTNet observes 27 fields including 6 main fields and 21 subfields. In 2017, we have finished the DIA photometry for all 2016 and 2017 data. Thus, it is possible to do a real-time DIA photometry from 2018. The DIA photometric data is used for finding events from the KMTNet event-finder. The KMTNet event-finder has been improved relative to the previous version, which already found 857 events in 4 main fields of 2015. We have applied the improved version to all 2016 data. As a result, we find that 2597 events are found, and out of them, 265 are found in KMTNet-K2C9 overlapping fields. For increasing the detection efficiency of event-finder, we are working on filtering false events out by machine-learning method. In 2018, we plan to measure event detection efficiency of KMTNet by injecting fake events into the pipeline near the image level. Thanks to high-cadence observations, KMTNet found fruitful interesting events including exoplanets and brown dwarfs, which were not found by other groups. Masses of such exoplanets and brown dwarfs are measured from collaborations with Spitzer and other groups. Especially, KMTNet has been closely cooperating with Spitzer from 2015. Thus, KMTNet observes Spitzer fields. As a result, we could measure the microlens parallaxes for many events. Also, the automated KMTNet PySIS pipeline was developed before the 2017 Spitzer season and it played a very important role in selecting the Spitzer target. For the 2018 Spitzer season, we will improve the PySIS pipeline to obtain better photometric results.

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Role of Blood Flow vs. $O_{2}$ Consumption in Nicotinamide-induced Increase $pO_{2}$ in a Murine Tumor (Nicotinamide에 의한 종양내 산소 분압의 증가에 있어서 혈류 또는 산소 소모의 역할)

  • Lee Intae;Demhartner Thomas J.;Cho Moon-June
    • Radiation Oncology Journal
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    • v.12 no.1
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    • pp.17-25
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    • 1994
  • We evaluated the effect of nicotinamide on cellular $O_{2}$ consumption and metabolic status i.e., adenylate phosphates and $NAD^{+}$in-vitro, and changes in blood flow in-vivo, to determine whether changes in cellular metabolism or increased oxygen availability, was responsible for increased tumor oxygenation. Thirty min, pre-incubation of cells with$\∼$4mM (= 500mg/kg) nicotinamide resulted in no change in cellular $O_{2}$ consumption. Similarly neither the adenylate Phosphates nor the cellular $NAD^{+}$levels were altered in the presence of $\∼$4mM nicontinamide. In-vivo, nicotinamide (500mg/kg) increased $O_{2}$ availability as estimated by changes in relative tumor blood flow (RBC flux). The changes in RBC flux measured by the laser Doppler method, were tumor volume dependent and increased from$\∼$35$ \% $ in$\∼$ 150$mm_{3}$tumors to$\∼$~75$ \% $ in$\∼$500$mm^{3}$ tumors. In conclusion, these observations indicate a reduction in local tissue $O_{2}$ consumption is not a mechanism of improved tumor oxygenation by nicotinamide in FSa II murine tumor model. The primary mechanism of increased $pO_{2}$ appears to be an increased local tumor blood flow.

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Estimation of Nursing Cost for Hemodialysis Using RBRVS(Resource Based Relative Value Scale);Moderately Intensive Patient (상대가치를 이용한 혈액투석실 간호수가 산정;중등도 대상자를 중심으로)

  • Kim, Moon-Sil;Moon, Sun-Young;Kim, Jung-A;Shim, Ok-Su;Kim, Ji-Hyun
    • Journal of Korean Academy of Nursing Administration
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    • v.9 no.2
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    • pp.205-216
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    • 2003
  • Purpose : This study wad aimed to estimate nursing cost for hemodialysis of secondary hospitals using Resource Based Relative Value Scale(RVRBS). Method : The first, calculated nursing workload for the hemodialysis of secondary hospitals. Second, measured each spent time according to 14 nursing behaviors. Third, computed Resource Based Relative Value(RBRV) scores and nursing expenses of hemodialysis nurse. Finally, estimated nursing cost for hemodialysis of secondary hospitals, Result & Conclusion : The mean RBRV scores for each nursing behaviors were from 218.9 to 383.9 point(mean=312.7). The high RBRV socres were 383.9(Complication during hemodialysis), 353.7(Access patient vascular), 345.7 (Patient Teaching). Nursing cost for hemodialysis was estimated 23,234(won).

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INFRARED [FE II] EMISSION LINES FROM RADIATIVE ATOMIC SHOCKS

  • KOO, BON-CHUL;RAYMOND, JOHN C.;KIM, HYUN-JEONG
    • Journal of The Korean Astronomical Society
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    • v.49 no.3
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    • pp.109-122
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    • 2016
  • [Fe II] emission lines are prominent in the infrared (IR) and important as diagnostic tools for radiative atomic shocks. We investigate the emission characteristics of [Fe II] lines using a shock code developed by Raymond (1979) with updated atomic parameters. We first review general characteristics of the IR [Fe II] emission lines from shocked gas, and derive their fluxes as a function of shock speed and ambient density. We have compiled available IR [Fe II] line observations of interstellar shocks and compare them to the ratios predicted from our model. The sample includes both young and old supernova remnants in the Galaxy and the Large Magellanic Cloud and several Herbig-Haro objects. We find that the observed ratios of the IR [Fe II] lines generally fall on our grid of shock models, but the ratios of some mid-IR lines, e.g., [Fe II] 35.35 µm/[Fe II] 25.99 µm, [Fe II] 5.340 µm/[Fe II] 25.99 µm, and [Fe II] 5.340 µm/[Fe II] 17.94 µm, are significantly offset from our model grid. We discuss possible explanations and conclude that while uncertainties in the shock modeling and the observations certainly exist, the uncertainty in atomic rates appears to be the major source of discrepancy.

Event Trigger Generator for Gravitational-Wave Data based on Hilbert-Huang Transform

  • Son, Edwin J.;Chu, Hyoungseok;Kim, Young-Min;Kim, Hwansun;Oh, John J.;Oh, Sang Hoon;Blackburn, Lindy;Hayama, Kazuhiro;Robinet, Florent
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.55.4-56
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    • 2015
  • The Hilbert-Huang Transform (HHT) is composed of the Empirical Mode Decomposition (EMD) and the Hilbert Spectral Analysis (HSA). The EMD decomposes any time series data into a small number of components called the Intrinsic Mode Functions (IMFs), compared to the Discrete Fourier Transform which decomposes a data into a large number of harmonic functions. Each IMF has varying amplitude and frequency with respect to time, which can be obtained by HSA. The time resolution of the modes in HHT is the same as that of the given time series, while in the Wavelet Transform, Constant Q Transform and Short-Time Fourier Transform, there is a tradeoff between the resolutions in frequency and time. Based on the time-dependent amplitudes of IMFs, we develop an Event Trigger Generator and demonstrate its efficiency by applying it to gravitational-wave data.

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Basic Survey for Evaluation of Instream flow at Natural Recovery Reach (자연형 하천 복원구간의 하천유지유량 산정을 위한 기초조사)

  • Sea, Kyu-Woo;Woo, Sang-Hwan;Kim, Gwang-Seob
    • Journal of Wetlands Research
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    • v.3 no.2
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    • pp.119-131
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    • 2001
  • This study uses HEC-RAS for the quantitative aspects and the QUAL2E model for the qualitative aspects of the flow of urban streams, where the natural recovery system is applied. The instream flow of the small streams is estimated using the numerical model by verifying the existing data with the acquired data. The characteristics of the model reach place more weight on the drought discharge around the ordinary discharge, and this is caused by the natural recovery system that maintains the existing bank. The data of direct discharge to the sewage treatment plant through the inception pipe, BOD, DO, temperature, and so forth, are the official data from the department of environment. Considering the characteristics of small streams, the factors for the QUAL2E model are estimated with the focus on the hydraulic conditions and the stream view. This study proposes the future improvements for the natural recovery system by investigating the practical use of the waterfront and the application of the proper instream flow. Also, the hydraulic and hydrological investigation of the covering rate by the natural vegetation and the meandering by the varying river way is performed.

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Model Study of Aesthetic Database System of Architectural Precedents for Design Reference (설계참조를 위한 건축선례의 미학적 정보체계 모형연구)

  • Kim, Kyong-Soo
    • Journal of architectural history
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    • v.5 no.2 s.10
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    • pp.83-95
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    • 1996
  • Computerized visual database construction of architectural precedents has just begun in some research institutes in the world. In Korea the first visual database has shown its testl version by S architectural design firm in september 1996. In this article the author discusses the historical contexts and the recent computerization cases, the traits, the uses and the limits of architectural visual database system of precedents. The forms and contents of data fields in two cases are compared with a focus on the description of architectural traits of each data entry. Compared to the KIA format, the S database has better performance for architectural design reference because it collects more pictures and drawings and larger texts for the field of architectural chracteristics. But this latter also is constrained by its capacity of memory and so lacks the reciprocity of the DOORS in the Graduate School of Design, Harvard University. A visual database system which has more flexible allocation of memory and respondent with the users is yet to be prepared. But this system also should be maintained by some experts in architectural history, theory and criticism, because their knowledge is essential for selection of precedents and revision of the data description. A full-fledged electronic visual database in architecture will not only save much effort for the architect, but also will change the architects' design behavior. Nevertheless this does not mean the automatic promotion of architects' creativity.

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Root coverage with a modified laterally positioned flap combined with a subepithelial connective tissue graft in advanced recession

  • Lee, Chun-Teh;Chang, Po-Chun;Touchan, Nawar;Royzman, Daniel
    • Journal of Periodontal and Implant Science
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    • v.44 no.6
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    • pp.300-306
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    • 2014
  • Purpose: A laterally positioned flap (LPF) combined with a subepithelial connective tissue graft (SCTG) is one of the conventional approaches for resolving gingival recession defects, with the advantages of flap flexibility and extended coverage of the tissue graft. However, thus far, evidence is lacking for the use of this technique for the treatment of advanced gingival recession defects. This report discusses three Miller class III cases with interproximal bone loss and wide and deep defects treated with a combination procedure of a modified laterally positioned flap (mLPF) and SCTG. Methods: mLPF combined with SCTG was performed for each case. The defect size and the degree of hypersensitivity at baseline and the final appointment in each case were documented. Results: The three cases had a mean initial defect of $7.7{\pm}1.5mm$ and a mean residual defect of $1.7{\pm}1mm$ at the 6-, 3-, and 36-month follow-up, respectively, after the root coverage surgery. The symptom of hypersensitivity was improved, and the patients were satisfied with the clinical outcomes. Conclusions: The results demonstrated that the combination of mLPF with SCTG is promising for treating these advanced cases with respect to obtaining the expected root coverage with the gingival tissue.

NEW VISIONS IN PEDIATRIC DENTISTRY - KEEPING HEALTHY TEETH CARIES FREE: PEDIATRIC CAMBRA PROTOCOLS (소아치과의 새로운 비전 - 우식 없는 건강한 치아를 보존하기 위해: 소아치과에서의 CAMBRA 사용)

  • Ramos-Gomez, Francisco;Kim, Young Jae;Ng, Man-Wai;Yang, Stephanie
    • Journal of the korean academy of Pediatric Dentistry
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    • v.40 no.1
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    • pp.72-81
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    • 2013
  • Early childhood caries prevalence has increased significantly in children ages 2~5 years. ECC disproportionately affects lower socioeconomic and minority groups, is a predictor for future decay, but is preventable and manageable. Caries risk assessment systematically derives a patient's caries risk and is important during an infant oral health visit beginning at age 1. Information obtained through a risk assessment can guide a disease management care path tailored to an individual's age and risk to effectively treat and manage one's caries disease process.