• Journal of Periodontal and Implant Science
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• v.53 no.3
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• pp.233-244
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• 2023

Purpose: An implant-supported prosthesis consists of an implant fixture, an abutment, an internal screw that connects the abutment to the implant fixture, and the upper prosthesis. Numerous studies have investigated the microorganisms present on the implant surface, surrounding tissues, and the subgingival microflora associated with peri-implantitis. However, there is limited information regarding the microbiome within the internal screw space. In this study, microbial samples were collected from the supragingival surfaces of natural teeth, the peri-implant sulcus, and the implant-abutment screw hole, in order to characterize the microbiome of the internal screw space in healthy subjects. Methods: Samples were obtained from the supragingival region of natural teeth, the peri-implant sulcus, and the implant screw hole in 20 healthy subjects. DNA was extracted, and the V3-V4 region of the 16S ribosomal RNA was sequenced for microbiome analysis. Alpha diversity, beta diversity, linear discriminant analysis effect size (LEfSe), and network analysis were employed to compare the characteristics of the microbiomes. Results: We observed significant differences in beta diversity among the samples. Upon analyzing the significant taxa using LEfSe, the microbial composition of the implant-abutment screw hole's microbiome was found to be similar to that of the other sampling sites' microbiomes. Moreover, the microbiome network analysis revealed a unique network complexity in samples obtained from the implant screw hole compared to those from the other sampling sites. Conclusions: The bacterial composition of the biofilm collected from the implant-abutment screw hole exhibited significant differences compared to the supra-structure of the implant. Therefore, long-term monitoring and management of not only the peri-implant tissue but also the implant screw are necessary.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.132-136
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• 2009

Purpose: WHO(world health organization) announced the FRAX Tool(fracture risk assessment) of new software in the beginning of 2008. FRAX Tool was considered various risk factor, being different from existing fracture risk. In this study, we wanted to know the fracture risk of following the changing of the risk factor of fracture. Materials and Methods: A total of 50 women aged 50~60 were studied. We measured BMD at the part of femur neck which was based on the age, weight, height of individual with GE, Lunar-prodigy. The control group is fracture risk without considering fracture risk factor. The experimental group is previous fracture, parent fracture, current smoking, glucocorticoid, rheumatoid arthritis, secondary osteoporosis, alcohol. if each items makes one 'existence', others are all 'nothing'. and the results produced major osteoporotic region and hip fracture risk in 10-years. Statistics used t-test of SPSS 12.0. Results: The average rate of increment of major osteoporotic region between control group and experimental group, previous fracture-74% increase, parent fracture-96% increase, current smoking-2% increase, glucocorticoid-61% increase, rheumatoid arthritis-29% increase, alcohol-20% increase, secondary osteoporosis-0.18% decrease. The average rate of increment of hip region between control group and experimental group, previous fracture-84% increase, parent fracture-5% increase, current smoking-72% increase, glucocorticoid-84% increase, rheumatoid arthritis-40% increase, alcohol-52% increase, secondary osteoporosis-1.69% decrease. Conclusions: Each fracture risk factor has different rate of increment between major osteoporotic and hip region while in occasion of the second osteoporosis it has little relation because of low P-value. We could know that a contribution of the risk factor is different between major osteoporotic and hip region.

• Molecules and Cells
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• v.27 no.1
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• pp.119-123
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• 2009

Porcine endogenous retroviruses (PERVs) gamma1 in the pig genome have the potential to act as harmful factors in xenotransplantation (pig-to-human). Long terminal repeats (LTRs) are known to be strong promoter elements that could control the transcription activity of PERV elements and the adjacent functional genes. To investigate the transcribed PERV gamma1 LTR elements in pig tissues, bioinformatic and experimental approaches were conducted. Using RT-PCR amplification and sequencing approaches, 69 different transcribed LTR elements were identified. And 69 LTR elements could be divided into six groups (15 subgroups) by internal variation including tandem repeated sequences, insertion and deletion (INDEL). Remarkably, all internal variations were indentified in U3 region of LTR elements. Taken together, the identification and characterization of various PERV LTR transcripts allow us to extend our knowledge of PERV and its transcriptional study.

• Journal of Species Research
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• v.5 no.3
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• pp.318-323
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• 2016

Acrobeles ciliatus (von Linstow, 1877) and Plectus parietinus (Bastian, 1865) are newly collected from Korea. Acrobeles is similar to those nematode belongs to Rhabditidae and Panagrolaimidae by having terminal bulb without medium bulb but different by having complex, vines shaped labial attachment. A. ciliatus differed from other Acrobeles species by lateral fields with two incisures, primary axils U-shaped, and secondary axils V-shaped. Head region set off with the neck, three high labial probolae present, each having 5 tines at inner margins and 5-7 at outer margins, and two elongate apical tines. Also, it differs from the longer female body. Plectus parietinus is distinguished from all other species of Plectus by the prominent hypodermal glands, the relatively small amphid, the distinct and well set-off lips and by the subdorsal distal caudal seta on the left side of the tail. Stoma without stylet. Oesophagus about 1/4 of total body length with terminal bulb. Anus ca. $100{\mu}m$ from posterior extremity. Vulva is at middle of body. Have spinneret on tail tip.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1647-1653
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• 2014

9,10-Bis(bromomethyl)phenanthrene reacted with fullerenes via a Diels-Alder reaction to give phenanthrene-substituted fullerene mono-adducts (PCMA) and bis-adducts (PCBA) as electron acceptors for organic photovoltaic cells (OPVs). The syntheses of the fullerene derivatives were confirmed by $^1H$ $^{13}C$ NMR spectroscopy and MALDI-TOF mass spectrometry. PCMA and PCBA showed better light absorption in the UV-visible region than $PC_{61}BM$. Their electrochemical properties were measured using cyclic voltammetry. Accordingly, the lowest unoccupied molecular orbital (LUMO) energy levels of PCMA and PCBA were -3.66 and -3.57 eV, respectively. Photovoltaic cells were fabricated with a ITO/PEDOT:PSS/poly(3-hexylthiophene)(P3HT):acceptor/LiF/Al configuration, where P3HT and PCBA are the electron donors and acceptors, respectively. The polymer solar cell fabricated using the P3HT:PCBA active layer showed a maximum power conversion efficiency of 0.71%.

• Molecules and Cells
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• v.24 no.1
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• pp.148-151
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• 2007

Porcine endogenous retroviruses (PERVs) in the pig genome represent a potential risk of infection in pig-to-human transplantation and are transmitted vertically. The solitary long terminal repeat (LTR) elements of the PERVs affect the replication properties of the individual viruses via their repeat sequences and by encoding a set of specific transcription factors. We examined the promoter activities of solitary LTR elements belonging to the PERV-A and -B families of the Korean domestic pig (KDP) using luciferase reporters. Three of the LTR structures (of PERV-A5-KDP, PERV-A7-KDP, PERV-A8-KDP) had different promoter activities in human HCT116 cells and monkey Cos7 cells, and potential negatively and positively acting regions affecting transcription were identified by deletion analysis. These data suggest that specific sequences in the U3 region of a given LTR element can affect the activities of promoter or enhancer elements in the PERV.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.395-398
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• 1999

In ac PDP(plasma Display Panel), the discharge characteristics is very important to display clear images. In this paper, we have studied the measurement of voltage transfer curves which show the discharge characteristics in AC PDP. The change of the effective wall capacitance during a discharge is also studied. These depend on lateral spreading of charge distribution and the strength of the discharge. As a parameter of the frequency, we observed the effects of the frequency in voltage transfer curves and in effective wall capacitance changes. As frequency increases, minimum sustain voltage and firing voltage decrease. In upper region of gap voltage the chance of the effective wall capacitance is independent of frequency.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.512-513
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• 2014

본 논문은 3상 인버터에서 직류단 션트 저항을 이용하여 전류를 복원하는 새로운 기법에 대하여 제안한다. 직류단 션트 저항을 이용하여 전류를 측정할 경우, 전동기의 구동에 따른 지령 전압 벡터의 변화에 따라 SVPWM 헥사곤 내부에는 전류의 측정이 불가능한 영역이 존재한다. 기존의 방법들은 지령 벡터가 전류 측정이 불가능한 영역에 위치할 때, 스위칭 패턴에 변화를 주는 방법들을 이용하였다. 그러나, 이 기법들은 스위칭 패턴을 바꾸기 때문에 소음 및 전류 왜곡의 원인이 된다. 본 논문에서는 스위칭 패턴의 변화 없이 전류를 추정할 수 있는 새로운 기법을 소개한다. 제안된 알고리즘의 효율성은 실험적 결과를 통해 증명한다.

• Journal of Acupuncture Research
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• v.39 no.4
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• pp.317-322
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• 2022

Gold thread therapy (GTT) continuously stimulates acupoints and is used to treat chronic conditions/diseases such as chronic lumbar pain. During the procedure gold thread is embedded into the skin and although gold thread is medically pure, GTT is an irreversible treatment where there is limited evidence on its safety. Here, we report a case of a 79-year-old woman being treated for low back pain who developed side effects following moving cupping therapy at a site of GTT (performed in the 1970s). Adverse reactions causing radiating pain persisted more than at least 9 days following moving cupping therapy. The symptoms of pain were evaluated using the numerical rating scale, and changes in tenderness and the state of bruising was recorded. Low back pain improved but the radiating low leg pain did not improve. This case highlights the need for caution when performing moving cupping therapy where GTT has been previously performed.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.5
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• pp.625-638
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• 1999

Air quality modeling for coastal urban region has been composed of a complex system including meteorological, chemical and physical processes and emission characteristics in complex terrain. In this study, we studied about an effect prediction for deposition phenomenon affecting on air quality in Pusan metopolitan metropolitan city. In air quality modeling including ship sources, a situation considered deposition process habe better result than not considered when compared with observed value. Air pollutants emitted into urban air during the daytime nearly removed through urban atmosphere polluted. Also these phenomena correlated concentration variation connent with sea/land breezes and terrain effect. Therefore we conclude that the concentration was low at daytime when deposition flux is high, and deposition effect on industrial complex and Dongrae region is considerable in particular.