• Title/Summary/Keyword: AFI

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ECG data compression using wavelet transform and adaptive fractal interpolation (웨이브렛 변환과 적응 프랙탈 보간을 이용한 심전도 데이터 압축)

  • 윤영노;이우희
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.12
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    • pp.45-61
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    • 1996
  • This paper presents the ECG data compression using wavelet transform (WT) and adaptive fractal interpolation (AFI). The WT has the subband coding scheme. The fractal compression method represents any range of ECG signal by fractal interpolation parameters. Specially, the AFI used the adaptive range sizes and got good performance for ECG data cmpression. In this algorithm, the AFI is applied into the low frequency part of WT. The MIT/BIH arhythmia data was used for evaluation. The compression rate using WT and AFI algorithm is better than the compression rate using AFI. The WT and AFI algorithm yields compression ratio as high as 21.0 wihtout any entropy coding.

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ECG Data Compression Using Wavelet Transform and Adaptive Fractal Interpolation (웨이브렛 변환과 적응 프랙탈 보간을 이용한 심전도 데이터 압축)

  • Lee, W.H.;Yoon, Y.R.;Park, S.J.
    • Proceedings of the KOSOMBE Conference
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    • v.1996 no.11
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    • pp.221-224
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    • 1996
  • This paper presents the ECG data compression using wavelet transform(WT) and adaptive fractal interpolation(AFI). The WT has the subband coding scheme. The fractal compression method represents any range of ECG signal by fractal interpolation parameters. Specially, the AFI used the adaptive range sizes and got good performance for ECG data compression. In this algorithm, the AFI is applied into the low frequency part of WT. The MIT/BIH arrhythmia data was used for evaluation. The compression rate using WT and AFI algorithm is better than the compression rate using AFI. The WT and AFI algorithm yields compression ratio as high as 21.0 without any entroy coding.

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Antioxidative and Anti-inflammatory Effects of Aurantii Fructus Immaturus Pharmacopuncture (지각 약침액의 항산화 및 항염증 효과에 관한 연구)

  • Kim, Sung-Jin;Park, Sang-Kyun
    • Korean Journal of Acupuncture
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    • v.27 no.2
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    • pp.13-24
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    • 2010
  • Objectives : Ulcerative colitis is a chronic relapsing inflammatory disease in the gastrointestinal tract. We investigated whether Aurantii fructus immaturus (AFI) pharmacopuncture has antioxidative and anti-inflammatory effects. Methods : in vitro experiments, 1,1-diphenyl-2-picryl hydrazyl (DPPH) free radical scavenging activity, superoxide dismutase (SOD) activity, prevention on $H_2O_2$-induced cell death in RAW264.7 cell line, DNA fragmentation, and cyclooxygenase-2 mRNA expression induced by lipopolysaccharide (LPS), were analyzed to investigate antioxidative and anti-inflammatory effect of AFI pharmacopuncture. in vivo experiment, a murine model of dextran sulfate sodium (DSS)-induced colitis was used to examine the effect of AFI pharmacopuncture on CV12 at different doses of 5 ${\mu}l$, 0.5 ${\mu}l$, 0.05 ${\mu}l$ for 10 days. Body weight, colon length and macroscopic features were investigated. Results : AFI pharmacopuncture showed DPPH free radical scavenging and SOD active effects in a dose-dependent manner. AFI pharmacopuncture showed a protective effect against $H_2O_2$-induced cell injury and also attenuated LPS-induced COX-2 mRNA expression. In a DSS- induced colitis murine model, however, AFI pharmacopuncture at CV12 had no anti-inflammatory effects. Conclusions : The present results suggest that AFI pharmacopuncture extract may have anti- inflammatory and antioxidative effects in vivo test, but further research on the underlying mechanism is required.

Impaired Autophagic Flux in Glucose-Deprived Cells: An Outcome of Lysosomal Acidification Failure Exacerbated by Mitophagy Dysfunction

  • Eun Seong Hwang;Seon Beom Song
    • Molecules and Cells
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    • v.46 no.11
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    • pp.655-663
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    • 2023
  • Autophagy dysfunction is associated with human diseases and conditions including neurodegenerative diseases, metabolic issues, and chronic infections. Additionally, the decline in autophagic activity contributes to tissue and organ dysfunction and aging-related diseases. Several factors, such as down-regulation of autophagy components and activators, oxidative damage, microinflammation, and impaired autophagy flux, are linked to autophagy decline. An autophagy flux impairment (AFI) has been implicated in neurological disorders and in certain other pathological conditions. Here, to enhance our understanding of AFI, we conducted a comprehensive literature review of findings derived from two well-studied cellular stress models: glucose deprivation and replicative senescence. Glucose deprivation is a condition in which cells heavily rely on oxidative phosphorylation for ATP generation. Autophagy is activated, but its flux is hindered at the autolysis step, primarily due to an impairment of lysosomal acidity. Cells undergoing replicative senescence also experience AFI, which is also known to be caused by lysosomal acidity failure. Both glucose deprivation and replicative senescence elevate levels of reactive oxygen species (ROS), affecting lysosomal acidification. Mitochondrial alterations play a crucial role in elevating ROS generation and reducing lysosomal acidity, highlighting their association with autophagy dysfunction and disease conditions. This paper delves into the underlying molecular and cellular pathways of AFI in glucose-deprived cells, providing insights into potential strategies for managing AFI that is driven by lysosomal acidity failure. Furthermore, the investigation on the roles of mitochondrial dysfunction sheds light on the potential effectiveness of modulating mitochondrial function to overcome AFI, offering new possibilities for therapeutic interventions.

Usefulness of Endoscopic Imaging to Visualize Regional Alterations in Acid Secretion of Noncancerous Gastric Mucosa after Helicobacter pylori Eradication

  • Uno, Kaname;Iijima, Katsunori;Abe, Yasuhiko;Koike, Tomoyuki;Takahashi, Yasushi;Ara, Nobuyuki;Shimosegawa, Tooru
    • Journal of Gastric Cancer
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    • v.16 no.3
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    • pp.152-160
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    • 2016
  • Purpose: Endoscopic diagnosis of gastric cancer (GC) that emerges after eradication of Helicobacter pylori may be affected by unique morphological changes. Using comprehensive endoscopic imaging, which can reveal biological alterations in gastric mucosa after eradication, previous studies demonstrated that Congo red chromoendoscopy (CRE) might clearly show an acid non-secretory area (ANA) with malignant potential, while autofluorescence imaging (AFI) without drug injection or dyeing may achieve early detection or prediction of GC. We aimed to determine whether AFI might be an alternative to CRE for identification of high-risk areas of gastric carcinogenesis after eradication. Materials and Methods: We included 27 sequential patients with metachronous GC detected during endoscopic surveillance for a mean of 82.8 months after curative endoscopic resection for primary GC and eradication. After their H. pylori infection status was evaluated by clinical interviews and $^{13}C$-urea breath tests, the consistency in the extension of corpus atrophy (e.g., open-type or closed-type atrophy) between AFI and CRE was investigated as a primary endpoint. Results: Inconsistencies in atrophic extension between AFI and CRE were observed in 6 of 27 patients, although CRE revealed all GC cases in the ANA. Interobserver and intraobserver agreements in the evaluation of atrophic extension by AFI were significantly less than those for CRE. Conclusions: We demonstrated that AFI findings might be less reliable for the evaluation of gastric mucosa with malignant potential after eradication than CRE findings. Therefore, special attention should be paid when we clinically evaluate AFI findings of background gastric mucosa after eradication (University Hospital Medical Information Network Center registration number: UMIN000020849).

A Study on the Growth Characteristics of Riparian Plants on the Artificial Floating Islands (인공섬 수생식물 생육특성에 관한 연구)

  • Kim, Yong-Kyu;Koo, Bon-Hak;Ahn, Tong-Mahn
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.4
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    • pp.25-35
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    • 2001
  • This study aims to find out the growth characteristics of riparian plants on the artificial floating islands (AFI). Three types of experiments were performed. The vegetation growth were compared by the plant-supporting materials; natural cotton mat, coir mat on the AFI or in the water, and natural soil at the waterfront. Major findings are; 1. The survival rate of riparian plants was 100% on both coir-mat and cotton-matislands, which implies that we may substitute cheaper cotton for expensive coir-mat. 2. Both natural cotton mat and coir mat were good for the growth of plants. Especially, the natural cotton mat was good for Sparganium stoloniferum and Miscanthus sacchariflorus, and the coir mat was good for Typha latifolia. 3. The growth rate of stem and root showed difference between the stem-removed plants and stem-remaining plants. As a whole, the growth rate of stem-removed plants was bigger than the one of stem-remaining plants. 4. The growth rate of plants showed difference between those grown on the AFI and those grown in the water. The growth rate of plant on the AFI was bigger than the one in the water. 5. The growth rate of plants on the AFI was bigger than the one on the natural soil at the waterfront.

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Algae and Nutrient Removal by Vegetated Artificial Floating Island (인공식물섬에 의한 조류(Algae)및 영양염류의 제거)

  • Park, Sun-Koo;Cho, In-Ki;Kwon, Oh-Byung;Mun, Jung-Soo;Um, Han-Yong;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.41 no.spc
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    • pp.93-98
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    • 2008
  • We investigated the effect on the removal of BOD, SS, TN and TP and algal growth inhibition of Vegetated Artificial Floating Island (VAFI), by examining microorganism activity and nutrient uptake in the batch test of various conditions: (1) Blank (Control group), (2) VAFI of $0.25m^2$, (3) AFI of $0.25m^2$ which has no vegetation, (4) buoyant plate of $0.25m^2$, (5) buoyant plate of $0.25m^2$ with linear media. The proportion of BOD removal in the VAFI, AFI, buoyant plate and buoyant plate with media were 82.7, 80.8, 45.2% and 59.6% respectively. TN removal in the VAFI, AFI and buoyant plate with media were 51.2, 31.7% and 25.1% respectively. TP removal in the VAFI, AFI, buoyant plate and buoyant plate with media were 23.3, 16.7, 10.0% and 13.3% respectively. Chlorophyll-${\alpha}$ removal in the VAFI was 97.9%. The factors of chlorophyll-${\alpha}$ removal in the VAFI accounted for the shading effect of 35.1%, microorganisms activity of 61%, and plant root of 1.8%.

Continuous Sampling Plans Based on AFI Curve (연속생산형(連續生産型)샘플링검사방식(檢査方式)의 선정(選定)에 관하여)

  • Bae, Do-Seon;Jang, Jung-Sun;Eom, Ju-Tae
    • Journal of Korean Institute of Industrial Engineers
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    • v.8 no.2
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    • pp.23-31
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    • 1982
  • A method of selecting parameters of Dodge-type continuous camping plans is proposed ; a sampling plan is designed so that its AFI curve passes through two designated points. AOQL contour lines are also drawn which can be used as a reference in choosing these points.

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ECG Data Compression Using Adaptive Fractal Interpolation (적응 프랙탈 보간을 이용한 심전도 데이터 압축)

  • 전영일;윤영로
    • Journal of Biomedical Engineering Research
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    • v.17 no.1
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    • pp.121-128
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    • 1996
  • This paper presents the ECG data compression method referred the adaptive fractal interpolation algorithm. In the previous piecewise fractal interpolation(PFI) algorithm, the size of range is fixed So, the reconstruction error of the PFI algorithm is nonuniformly distributed in the part of the original ECG signal. In order to improve this problem, the adaptive fractal interpolation(AEI) algorithm uses the variable range. If the predetermined tolerance was not satisfied, the range would be subdivided into two equal size blocks. large ranges are used for encoding the smooth waveform to yield high compression efficiency, and the smaller ranges are U for encoding rapidly varying parts of the signal to preserve the signal quality. The suggested algorithm was evaluated using MIT/BIH arrhythmia database. The AEI algorithm was found to yield a relatively low reconstruction error for a given compression ratio than the PFI algorithm. In applications where a PRD of about 7.13% was acceptable, the ASI algorithm yielded compression ratio as high as 10.51, without any entropy coding of the parameters of the fractal code.

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