• Title/Summary/Keyword: differential detection

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The Role of Functional Imaging Techniques in the Dementia (치매 환자에서 기능 영상법의 역할)

  • Ryu, Young-Hoon
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.3
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    • pp.209-217
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    • 2004
  • Evaluation of dementia in patients with early symptoms of cognitive decline is clinically challenging, but the need for early, accurate diagnosis has become more crucial, since several medication for the treatment of mild to moderate Alzheimer' disease are available. Many neurodegenerative diseases produce significant brain function alteration even when structural imaging (CT or MRI) reveal no specific abnormalities. The role of PET and SPECT brain imaging in the initial assessment and differential diagnosis of dementia is beginning to evolve vapidly and growing evidence indicates that appropriate incorporation of PET into the clinical work up can improve diagnostic and prognostic accuracy with respect to Alzheimer's disease, the most common cause of dementia in the geriatric population. in the fast few years, studios comparing neuropathologic examination with PET have established reliable and consistent accuracy for diagnostic evaluations using PET - accuracies substantially exceeding those of comparable studies of diagnostic value of SPECT or of both modalities assessed side by side, or of clinical evaluations done without nuclear imaging. This review deals the role of functional brain imaging techniques in the evaluation of dementias and the role of nuclear neuroimaging in the early detection and diagnosis of Alzheimer's disease.

Facial Image Segmentation using Wavelet Transform (웨이브렛 변환을 적용한 얼굴영상분할)

  • 김장원;박현숙;김창석
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.3
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    • pp.45-52
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    • 2000
  • In this study, we propose the image segmentation algorithm for facial region segmentation. The proposed algorithm separates the mean image of low frequency band from the differential image of high frequency band in order to make a boundary using HWT, and then we reduce the isolation pixels, projection pixels, and overlapped boundary pixels from the low frequency band. Also the boundaries are detected and simplified by the proposed boundary detection algorithm, which are cleared on the thinning process of 1 pixel unit. After extracting facial image boundary by using the proposed algorithm, we make the mask and segment facial image through matching original image. In the result of facial region segmentation experiment by using the proposed algorithm, the successive facial segmentation have 95.88% segmentation value.

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Detection of Magnetic Nanoparticles in Tissue Using Magneto-Motive DP-OCT

  • Oh, Jung-Hwan;Lee, Ho;Kim, Jee-Hyun
    • Journal of the Optical Society of Korea
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    • v.11 no.1
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    • pp.26-33
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    • 2007
  • We demonstrate the capability of differential-phase optical coherence tomography (DP-OCT) to detect superparamagnetic iron oxide (SPIO) nanoparticles taken up by liver parenchymeal macrophages (Kupffer cells). We apply an external time-varying high-intensity focused magnetic field. Our experiments demonstrate a novel diagnostic modality to detect macrophages that have taken up SPIO nanoparticles. Magnetic force acting on the nanoparticles was varied by applying a sinusoidal current to a solenoid containing a conical iron core that substantially increased and focused the magnetic field strength ($B_{max}$ = 2 Tesla). $ApoE^{-/-}$ mice were sacrificed 2 days post intravenous injections of different SPIO doses (1.0, and 0.1 mmol Fe/kg body weight). Livers of $ApoE^{-/-}$ mice with and without injection of SPIO nanoparticles were investigated using DP-OCT, which detects tissue movement with nanometer resolution. Frequency response of iron-laden liver movement was twice the stimulus frequency. Movement was not observed in livers of control mice. Results of our experiments indicate DP-OCT is a candidate methodology to detect tissue based macrophages containing SPIO nanoparticles excited by an external focused magnetic field.

Modified Glassy Carbon Electrode with Polypyrrole Nanocomposite for the Simultaneous Determination of Ascorbic acid, Dopamine, Uric acid, and Folic Acid

  • Ghanbari, Khadijeh;Bonyadi, Sepideh
    • Journal of Electrochemical Science and Technology
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    • v.11 no.1
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    • pp.68-83
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    • 2020
  • A fast and simple method for synthesis of CuxO-ZnO/PPy/RGO nanocomposite by electrochemical manner have been reported in this paper. For testing the utility of this nanocomposite we modified a GCE with the nanocomposite to yield a sensor for simultaneous determination of four analytes namely ascorbic acid (AA), dopamine (DA), uric acid (UA), and folic acid (FA). Cyclic voltammetry (CV) and Differential pulse voltammetry (DPV) selected for the study. The modified electrode cause to enhance electron transfer rate so overcome to overlapping their peaks and consequently having the ability to the simultaneous determination of AA, DA, UA, and FA. To synthesis confirmation of the nanocomposite, Field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, and electrochemical impedance spectroscopy (EIS) were applied. The linearity ranges were 0.07-485 μM, 0.05-430 μM, 0.02-250 μM and 0.022-180 μM for AA, DA, UA, and FA respectively and the detection limits were 22 nM, 10 nM, 5 nM and 6 nM for AA, DA, UA, and FA respectively Also, the obtained electrode can be used for the determination of the AA, DA, UA, and FA in human blood, and human urine real samples.

A Mathematical Model Proposed for the Prediction of the Fate of Priority Organic Pollutants Spilled in Streams: Dynamic Simulations and Sensitivity Analysis (하천에 유입된 유독성 유기오염물의 농도분포를 예측하기 위한 수학적 모형의 개발: Dynamic simulations 및 민감도 분석)

  • Ko, Kwang Baik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.2
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    • pp.265-274
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    • 1992
  • A mathematical model was proposed to predict the fate of a priority organic pollutant, anthracene, accidently spilled into a stream. The model consists of 6 differential equations with 5 input variables and 9 rate constants. Volatilization, biodegradation, adsorption/desorption, photodegradation as well as the convective inputs and outputs are included in the model. As a result of a series of dynamic simulations and sensitivity analyses under the given conditions, the concentrations of the organic chemical could be predicted within a detection limit in the stream. It was also suggested that the rate constant for diffusion/transport and adsorption rate constant are the most influential ones for predicting the chemical conentrations in dissolved and particulate phase. The model proposed appears to be a useful tool for assessing chemical spills.

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SELDI-TOF MS Combined with Magnetic Beads for Detecting Serum Protein Biomarkers and Establishment of a Boosting Decision Tree Model for Diagnosis of Pancreatic Cancer

  • Qian, Jing-Yi;Mou, Si-Hua;Liu, Chi-Bo
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.1911-1915
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    • 2012
  • Aim: New technologies for the early detection of pancreatic cancer (PC) are urgently needed. The aim of the present study was to screen for the potential protein biomarkers in serum using proteomic fingerprint technology. Methods: Magnetic beads combined with surface-enhanced laser desorption/ionization (SELDI) TOF MS were used to profile and compare the protein spectra of serum samples from 85 patients with pancreatic cancer, 50 patients with acute-on-chronic pancreatitis and 98 healthy blood donors. Proteomic patterns associated with pancreatic cancer were identified with Biomarker Patterns Software. Results: A total of 37 differential m/z peaks were identified that were related to PC (P < 0.01). A tree model of biomarkers was constructed with the software based on the three biomarkers (7762 Da, 8560 Da, 11654 Da), this showing excellent separation between pancreatic cancer and non-cancer., with a sensitivity of 93.3% and a specificity of 95.6%. Blind test data showed a sensitivity of 88% and a specificity of 91.4%. Conclusions: The results suggested that serum biomarkers for pancreatic cancer can be detected using SELDI-TOF-MS combined with magnetic beads. Application of combined biomarkers may provide a powerful and reliable diagnostic method for pancreatic cancer with a high sensitivity and specificity.

Malignancies in children who present with bone pain (뼈의 통증이 있을 때 감별해야 할 악성종양)

  • Lee, Jun Ah
    • Clinical and Experimental Pediatrics
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    • v.51 no.8
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    • pp.792-796
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    • 2008
  • Bone pain in a child could be associated with cancer as an initial manifestation of the disease. The childhood malignancies that frequently present bone pain are leukemia, neuroblastoma, and primary bone tumors such as osteosarcoma and Ewing sarcoma. Persistent bone or joint pain associated with swelling, mass, or limitation of motion implies underlying serious causes. Systemic manifestations such as lymphadenopathy, hepatosplenomegaly, fever, fatigue, night sweat, and laboratory abnormalities are also suggestive of malignancy. The index of suspicion tends to be low since less than 1% of children who complain of bone pain are diagnosed as cancer. Nonetheless, pediatricians should be alert to the possibilities of cancer since early detection and prompt treatment might reduce mortality.

Adsorptive Stripping Voltammetry of Indium-Morin Complex (Indium-Morin 착물에 관한 흡착벗김전압전류법적 연구)

  • Se Chul Sohn;Tae Yoon Eom;Yeong Kyeong Ha;Ki-Suk Jung
    • Journal of the Korean Chemical Society
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    • v.35 no.5
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    • pp.506-511
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    • 1991
  • A sensitive adsorptive stripping voltammetric study was investigated on the complex of indium with morin at a hanging mercury drop electrode in 0.1 M acetate buffer (pH 3.20) solution. The adsorption phenomena were observed by differential-pulse voltammetry. The effects of various analytical conditions were discussed on the reduction peak current of the adsorbed complex on the surface of HMDE. Interferences by other trace metals and surfactant were also discussed. Detection limit was 2.6 nM of indium after 90 second deposition time, and the relative standard deviation (n = 7) at 4TEX>${\mu}g$/l indium was 2.0%.

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Radial Pulse Wave Detection system for the Korean Medicine (한방용(韓方用) 맥파 검출시스템)

  • Lee, H.J.;Kim, J.W.;Kim, H.O.;Park, Y.B.;Huh, W.
    • Proceedings of the KOSOMBE Conference
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    • v.1991 no.11
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    • pp.66-69
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    • 1991
  • This paper describes a design of transducer for non-invasively detecting pressure radial pulse wave in aterial system and a recording system that for the studing the aterial pulse diagnosis of korean traditional medicine. The mechanism of transducer is composed of sensing mechanism, pressure sensor, conditioning amplifier. The variation of radial pulse pressure in the sensing mechanism is converted to the electric signal by piezo-resistive pressure sensor and it converted to the digital signal after preprocessing via A/D converter. The converted signals inputed to the computer as data files and then it display to the monitor for waveform watching and this datas can be used as the aterial pulse diagnosis data. This system effectively detect non-differential radial pulse wave and we conside that if analizing the recorded radial pulse wave, compared each other, it can be helpful in quantify radial pulse wave diagonosis of the Korean traditional medicine.

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An Ultra-precision Electronic Clinometer for Measurement of Small Inclination Angles

  • Tan, Siew-Leng;Kataoka, Satoshi;Ishikawa, Tatsuya;Ito, So;Shimizu, Yuuki;Chen, Yuanliu;Gao, Wei;Nakagawa, Satoshi
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.23 no.6
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    • pp.539-546
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    • 2014
  • This paper describes an ultra-precision electronic clinometer, which is based on the capacitive-based fluid type, for detection of small inclination angles. The main parts of the clinometer low-noise electronics are two capacitance measurement circuits for converting the capacitances of the capacitors of the clinometer into voltages, and a differential amplifier for obtaining the difference of the capacitances, which is proportional to the input inclination angle. A 16 bit analog to digital (AD) converter is also embedded into the same circuit board, whose output is sent to a PC via RS-232C, for achieving a small noise level down to tens of ${\mu}v$. A compensation method, which is referred to as the delay time method for shortening the stabilization time of the sensor was also discussed. Experimental results have shown the possibility of achieving a measurement resolution of $0.0001^{\circ}$ as well as the quick measurement with the delay time method.