• Journal of Sensor Science and Technology
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• v.2 no.1
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• pp.87-94
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• 1993

CdS and Se thin films were deposited on slide glass by EBE method respectively and surface morphology, crystal structure, electrical and optical properties were investigated by substrate temperature and annealing. The deposited CdS film was well fabricated with cubic structure at substrate temperature of $150^{\circ}C$. Se film was deposited with noncrystal structure until substrate temperature of $100^{\circ}C$, but Se film was grown with monoclinic structure at substrate temperature of $150^{\circ}C$. And so, after annealing at $150^{\circ}C$ for 15min, noncrystalline Se was proved to be hexagonal structure. Finally, the maximum output of Se/CdS heterojunction at 5000 lux was 4 $mW/cm^{2}$ and maximum spectral sensitivity was represented at 585nm.

• The Journal of Advanced Prosthodontics
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• v.13 no.5
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• pp.292-303
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• 2021

PURPOSE. The aim of this in vitro study was to evaluate the effect of silane and universal adhesive applications on the micro-shear bond strength (µSBS) of different resin-matrix ceramics (RMCs). MATERIALS AND METHODS. A total of 120 slides (14 × 12 × 1 mm) were produced from 5 different RMC materials (GC Cerasmart [GC]; Brilliant Crios [BC]; Grandio blocs [GB]; Katana Avencia [KA]; and KZR-CAD HR 2 [KZR]) and sandblasted using 50 ㎛ Al₂O₃ particles. Each RMC material was divided into six groups according to the surface conditioning (SC) method as follows: control (G1), silane primer (G2), silane-free universal adhesive (G3), silane-containing universal adhesive (G4), silane primer and silane-free universal adhesive (G5), and silane primer and silane-containing universal adhesive (G6). Three cylindric specimens made from resin cement (Bifix QM) were polymerized over the treated surface of each slide (n = 12). After thermal cycling (10000 cycles, 5 - 55℃), µSBS test was performed and failure types were evaluated using a stereomicroscope. Data were analyzed using 2-way ANOVA and Tukey tests (α = .05). RESULTS. µSBS values of specimens were significantly affected by the RMC type and SC protocols (P < .001) except the interaction (P = .119). Except for G2, all SC protocols showed a significant increase in µSBS values (P < .05). For all RMCs, the highest µSBS values were obtained in G4 and G6 groups. CONCLUSION. Only silane application did not affect the µSBS values regardless of the RMC type. Moreover, the application of a separate silane in addition to the universal adhesives did not improve the µSBS values. Silane-containing universal adhesive was found to be the best conditioning method for RMCs.

• The Journal of the Korea Contents Association
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• v.19 no.5
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• pp.624-631
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• 2019

The purpose of this study was to observe the influence of adhesive force of lifter on powdered fingermark. First, an experiment was conducted to measure the adhesive force of five kinds of lifters. Second, each fingermark deposited on slide glass was developed using four kinds of powders. Then, these were transferred to lifter, and the quality of the transferred fingermark was observed. As a result of measuring the adhesive force of the lifter using the ASTM D3121-17 rolling ball tack method, the difference in adhesion between the lifters except the gelatin lifter was small. Also, it was confirmed that the quality of the transferred fingermark was not significantly related to the adhesive force of the lifter. However, if the quality of the transferred fingermark is not good when transferring to a gelatin lifter which is a lifter having a weak adhesive force, additional transfer is possible.

• BioChip Journal
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• v.16
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• pp.82-98
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• 2020

We report a quantitative and systematic method for determining 3D-printing and surface-treatment conditions that can help improve the optical quality of direct-printed microfluidic devices. Digital light processing (DLP)-stereolithography (SLA) printing was extensively studied in microfluidics owing to the rapid, one-step, cleanroom-free, maskless, and high-definition microfabrication of 3D-microfluidic devices. However, optical imaging or detection for bioassays in DLP-SLA-printed microfluidic devices are limited by the translucence of photopolymerized resins. Various approaches, including mechanical abrasions, chemical etching, polymer coatings, and printing on transparent glass/plastic slides, were proposed to address this limitation. However, the effects of these methods have not been analyzed quantitatively or systematically. For the first time, we propose quantitative and methodological determination of 3D-printing and surface-treatment conditions, based on optical-resolution analysis using USAF 1951 resolution test targets and a fluorescence microbead slide through 3D-printed coverslip chips. The key printing parameters (resin type, build orientation, layer thickness, and layer offset) and surface-treatment parameters (grit number for sanding, polishing time with alumina slurry, and type of refractive-index-matching coatings) were determined in a step-wise manner. As a result, we achieved marked improvements in resolution (from 80.6 to 645.1 lp/mm) and contrast (from 3.30 to 27.63% for 645.1 lp/mm resolution). Furthermore, images of the fluorescence microbeads were qualitatively analyzed to evaluate the proposed 3D-printing and surface-treatment approach for fluorescence imaging applications. Finally, the proposed method was validated by fabricating an acoustic micromixer chip and fluorescently visualizing cavitation microstreaming that emanated from an oscillating bubble captured inside the chip. We expect that our approach for enhancing optical quality will be widely used in the rapid manufacturing of 3D-microfluidic chips for optical assays.

• The Korean Journal of Cytopathology
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• v.18 no.2
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• pp.119-125
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• 2007

Urine cytology is an important screening tool for urinary tract neoplasms. Liquid-based preparation methods, such as $ThinPrep^{(R)}$, have been introduced for non-gynecological samples. We aimed to assess the diagnostic accuracy of liquid-based preparations in urine cytology by comparing the results of the conventional Cytospin preparation method for the same samples. A total of 236 cases subject to urine cytology were enrolled in this study from January 2005 to December 2005. All cases were subjected to cystoscopy and if a malignancy was suspected, a biopsy was performed. Urine cytology slides were made using the $ThinPrep^{(R)}$ preparation method and the conventional Cytospin and/or direct smear method from the individual samples. The results of urine cytology were compared with the final cystoscopic or histological diagnoses. We analyzed the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of both cytology preparation methods. A total of 236 slides made using the liquid based method were satisfactory for slide quality, whereas 5 slides (2.1%) prepared by conventional methods were unsatisfactory because of air-drying, a thick smear, or a bloody or inflammatory background. The $ThinPrep^{(R)}$ method showed 53.1% sensitivity, 92.6% specificity, a 92,6% positive predictive value, a 94.1% negative predictive value and 85,6% accuracy, while the conventional method showed 51% sensitivity, 98.4% specificity, a 92.6% positive predictive value, a 98.4% negative predictive value and 88,6% accuracy. Although the diagnostic values were equivalent between the use of the two methods, the quality of the cytology slides and the time consumed during the microscopic examination for a diagnosis were superior for the $ThinPrep^{(R)}$ method than for the conventional method. In conclusion, our limited studies have shown that the use of the liquid based preparation method is beneficial to improve the quality of slides and reduce the duration for a microscopic examination, but did not show better sensitivity, accuracy and predictive values.

• Journal of Biomedical Engineering Research
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• v.23 no.3
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• pp.235-241
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• 2002

The detection of tubercle bacilli (TB) from sputum smear is one of the fast and inexpensive methods for diagnosis of tuberculosis. For this method. sputum smears are usually flexed by heating and stained by acid-fast staining method, and then examined under an optical microscope. Two Procedures are commonly used fur TB staining. One is hot staining and the other is cold staining method. The Ziehl-Neelsen method which is a hot staining method is widely used in Korea because its stained color is more vivid However, the conventional automated stainer has to fix the sputum smear on a slide manually and the stain is not so vivid because it has not heating function. In an effort to save labor and minimize variations in manual staining Procedure. we developed an automated stainer with heating function. The entire staining process is fully automated. from fixation to final washing and drying. With the automated methods, five slides can be flexed and stained in 21 minutes at consistent high quality We compared the concordance rate between the two methods for 91 sputum samples to validate the stain quality of the developed automated stainer. As the results, the concordant rate between the two methods was 95% and there was no significant difference (p>0.05)

• Journal of Photoscience
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• v.9 no.2
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• pp.457-459
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• 2002

Sunlight causes various types of adverse skin changes on the sun-exposed areas of the skin, in which the most hazardous one is the induction of malignant skin tumours. FT -IR spectra were obtained from specimens excised from normal skin, BCCs, SCCs, MMs, nevi, lesions of solar keratosis and Bowen's disease. Tissue samples from freshly frozen specimens were cut into 2 sections in strictly sequential order to be stained with H & E for histopathological analysis, and then to be air-dried on CaF$_2$ slide glasses for further spectral data acquisition from defined area of interest. Intra- and inter-sample variations were estimated within grouped lesion categories according to each skin component. Mean spectra for each type of tissue pathology in the 800-1800 $cm^{-1}$ / region was interpreted using the classical group frequency approach that showed the most visible differences in spectra of benign, premalignant and malignant changes directly related to protein conformation and nucleic acid bases. The relative intensity of the nucleic acid peak was increased with progression to malignancy. In addition, PCA was able to evaluate and maximise the differences in the spectra by reducing the number of variables characterizing each patient and pathology category. This type of approach to non-destructively estimate the complexity of IR-spectra of inhomogeneous samples such as skin demonstrates the advantage of FT -IR microspectroscopy to be able to observe diseased states (benign, premalignant, malignant) and distinguish them from normal against a huge background of inter- and intra-subject variability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.772-778
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• 2012

In this paper, the states and the parameters in the dynamic system are simultaneously estimated by applying the UKF(Unscented Kalman Filter), which is widely used for estimating the state of non-linear systems. Estimating the parameter is very important in various fields, such as system control, modeling, analysis of performance, and prediction. Most of the dynamic systems which are dealt with in engineering have non-linearity as well as some noise. Therefore, the parameter estimation is difficult. This paper estimates the states and the parameters applying to the UKF, which is a non-linear filter and has strong noise. The augmented equation is used by including the addition of the parameter factors to the original state equation of the system. Moreover, it is simulated by applying to a 2-DOF(Degree of Freedom) dynamic system composed of the pendulum and the slide. The measurement noise of the dynamic equation is assumed to be a Gaussian distribution. As the simulation results show, the proposed parameter estimation performs better than the LSM(Least Square Method). Furthermore, the estimation errors and convergence time are within three percent and 0.1 second, respectively. Consequentially, the UKF is able to estimate the system states and the parameters for the system, despite having measurement data with noise.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7381-7384
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• 2015

This study was conducted to 1206 women who had cervical cancer screening at Chonburi Cancer Hospital. The spilt-sample study aimed to compare the efficacy of abnormal cervical cells detection between liquid-based cytology (LBC) and conventional cytology (CC). The collection of cervical cells was performed by broom and directly smeared on a glass slide for CC then the rest of specimen was prepared for LBC. All slides were evaluated and classified by The Bethesda System. The results of the two cytological tests were compared to the gold standard. The LBC smear significantly decreased inflammatory cell and thick smear on slides. These two techniques were not difference in detection rate of abnormal cytology and had high cytological diagnostic agreement of 95.7%. The histologic diagnosis of cervical tissue was used as the gold standard in 103 cases. Sensitivity, specificity, positive predictive value, negative predictive value, false positive, false negative and accuracy of LBC at ASC-US cut off were 81.4, 75.0, 70.0, 84.9, 25.0, 18.6 and 77.7%, respectively. CC had higher false positive and false negative than LBC. LBC had shown higher sensitivity, specificity, PPV, NPV and accuracy than CC but no statistical significance. In conclusion, LBC method can improve specimen quality, more sensitive, specific and accurate at ASC-US cut off and as effective as CC in detecting cervical epithelial cell abnormalities.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.89-94
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• 2001

Recently, single cell gel electrophoresis, also known as comet assay, is widely used for the detection and measurement of DNA strand breaks in vitro and in vivo in many toxicological fields such as radiation exposure, human monitoring and toxicity evaluation. As well defined, comet assay is a sensitive, rapid and visual method for the detection of DNA strand breaks in individual cells. Briefly, a small number of damaged cells suspended in a thin agarose gel on a microscope slide were lysed, unwinded, electrophoresed, and stained with a fluorescent DNA binding dye. The electric current pulled the charged DNA from the nucleus such that relaxed and broken DNA fragments migrated further. The resulting images which were subsequently named for their appearance as comets, were measured to determine the extent of DNA damages. However, some variations could be occurred in procedures, laboratories's conditions and kind of cells used. Hence, to overcome and to harmonize these matters in comet assay, International Workshop on Genotoxicity Test Procedure (IWGTP) was held with several topics including comet assay at Washington D.C. on March, 1999. In spite of some consensus in procedures and conditions in IWGTP, there are some problems still remained to be solved. In this respect, we attempted to set the practical optimal conditions in the experimental procedures such as lysis, unwinding, electrophoresis and neutralization conditions and so on. First of all, we determined optimal lysis and unwinding time by using 150 $\mu$M methyl methanesulfonate (MMS) which is usually used concentration. And then, we determined optimal positive control concentrations of benzo(a)pyrene (BaP) and MMS in the presence and absence of S9 metabolic activation system, respectively.