• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.690-693
• /
• 2003

Soft x-ray microscopy provides a unique set of capabilities in-between those of visible light and electron microscopy. It has long been recognized that nature provides a 'water window' spectral region between the K shell x-ray absorption edges of carbon (~290eV) and oxygen (~540eV), where organic materials show strong absorption and phase contrast, while water is relatively non-absorbing. This enables imaging of hydrated biological specimens that are several microns thick with high intrinsic contrast using x-rays with a wavelength of 2.3~4.4nm. Soft X-ray microscopy is therefore well suited to the study of specimens like single biological cells. The most direct advantage of X-ray microscope is their high spatial resolution when compared with visible light microscopes, combined with an ability to image hydrated specimens that are several microns with a minimum of preparation. Our study describes the conceptual design of soft x-ray microscope system based on a laser-based source for biomedical application with high resolution ($\leq$50nm) and short exposure time ($\leq$30sec).

• Korean Journal of Microbiology
• /
• v.9 no.4
• /
• pp.169-174
• /
• 1971

Ultrastructural observations of mycelial and tissue phase with dimorphic fungal pathogen Coccidioides immitis were studied by electron microscopy of thin sections. 1. In mycelial phase of C.immitis contains normal cell components such as nucleus, mitochondria, endoplamsic reticulum, intracytoplasmic membrane system, cell wall and cell membrane as observed in the other encaryotic cells. 2. In tissue phase of C. immitis was larger than mycelial phase in cell size and observed much more vacuoles than mycelial phase. 3. In the contrast of mycelial phase of C. immitis, the tissue phase of cells were observed fibril form of capsular layer.

• Korean Journal of Materials Research
• /
• v.13 no.10
• /
• pp.651-657
• /
• 2003

Ultrasonic microscope has been used to detect the defects on surface or inner solid. Conventionally, it has used at a single operating frequency. The resolution and quality of the measured images are determined by a characteristic of the transducer of the ultrasonic microscope. The conventional ultrasonic microscope has been used envelope detector to detect the amplitude of reflected signal, but the changes in amplitude is not sensitive enough for specimen with microstructure that in phase. In this paper, we have studied multi-frequency depth resolution enhancement with ultrasonic reflection microscope for the reflectors of a stainless steel reference specimen and a reference calibration block to be used as the material in nuclear power plants for ISI, PSI. Increased depth resolution can be obtained by taking two, three-dimensional images at more that one frequency and numerically combining the results. As results of the experiment, we could get enhanced images with the rate of contrast in proportion and high quality signal distribution for the image to the changing rate of depth for the reflectors of the two kinds of specimens.

• The Journal of Korean Academy of Prosthodontics
• /
• v.60 no.1
• /
• pp.1-8
• /
• 2022

Purpose. The present study aimed to investigate the effective cleaning of healing abutment (HA) using Healing abutment case (HA case) by observing oral microorganisms with phase contrast microscope. Materials and methods. 32 patients with two or more implants placed in the same jaw, a total of 64 HAs (experimental group 32, control group 32) were selected and the control was cleaned with an alcohol swab. At the first and second visits, each group was observed before cleaning, and the experimental group was additionally observed after cleaning at the first visit. A 400× phase contrast microscope was used for the observation of oral microorganisms for its amounts. Results. There was no significant difference in the amount of oral microorganisms was found between the groups at the first visit, no significant difference according to gender, maxilla or mandible, and buccal or lingual surface. There was a statistically significant difference in the amount of oral microorganisms according to supra-gingival and sub-gingival (P<.05), There was also a significant difference in the comparison before and after cleaning in the experimental group (P<.05). There was a significant difference in the amount of oral microorganisms in each group at second visit (P<.05). Conclusion. Healing abutment cleaning using healing abutment case solution is more effective than simple cleaning with alcohol swab.

• The Journal of Korean Academy of Prosthodontics
• /
• v.17 no.1
• /
• pp.47-59
• /
• 1979

In order to study the morphologic changes of the unfixed odontoblasts suspended in phenol solution of several different concentrations, the author carried out the extraction of lower incisor of S-D strain rats to collect the odontoblasts, and the cells obtained were suspended immediately in saline solution. After observing the odontoblasts in fresh state, the saline solution was substituted with 0.125%, 0.25% 0.5%, 1% and 2% diluted phenol solutions. The morphologic changes were examined with phase contrast microscope at intervals of 10, 30, and 60 minutes. The results were as follows: 1. In saline solution the odontoblast showed cytoplasmic swelling, slender cytoplasmic process, thick rim nuclear membrane with increased dark contrast, and prominent nucleoli and chromatin granules with lapse of time intervals. In accordance with time intervals, blisters appeared in the supranuclear zone and increased its size and moved outward of the cytoplasmic membrane resulting detachment from the cell membrane. The phase dark cytoplasmic granules were increased in its dark contrast and in its size. 2. In 0.125% and 0.25% phenol solution, the odontoblasts and its nucleus shrunk immeidately and its contrast of cellular components was increased. With the lapse of time, the phase-dark granules in cytoplasm were aggregated, and several blisters were formed in and out of the cells. The outline of cytoplasmic membrane was also obscured. 3. In 0.5% phenol solution, the necleus shrunk at once, but soon after it revealed karyolysis accompanying dark contrast of neclear components such as nuclear membrane, nucleoli, and chromatin granules. On the contrary, the cytoplasmic granules showed aggregation and increased dark contrast, small and large blisters were formed in and out of the odontblasts and the outline of cytoplasmic membrane became obscured. 4. In 1% phenol solution, it showed shrinkage of odontblasts and its nuclei with thick rim nuclear membrane, aggregation of chromatin granules and occasional karyorrhexis. The dark contrast of cytoplasmic granules was increased and aggregated each other. But the blister formation could not be found. 5. In 2% phenol solution, it showed the shrinkage of odontoblasts and pyknotic nuclei with increased dark contrast of nucleoli and chromatin granules. The number of cytoplasmic granules was decreased by aggregation. But the blister formation could not be found as in 1% phenol solution.

• Journal of Veterinary Clinics
• /
• v.7 no.2
• /
• pp.497-500
• /
• 1990

This study was carried out determine whether Unopette can be used for the observation of sperm morphology and sperm Concentration. Rabbit sperm and frozen-thawed bovine sperm were observed with phase contrast microscope after dilution with Unopette acooriding to duration of preservation at 3～5$^{\circ}C$. Sperm using Unopette showed high normal sperm(％) than sperm using hematoxylin-eosin until 48 hours. Sperm using Unopette revealed no difference in sperm concentration until 24 hours, as compared with control sperm. As a result, Unopette was assessed as appropriate solution for preservation in terms of morphological observation and sperm concentration.

• Journal of Korea Multimedia Society
• /
• v.5 no.4
• /
• pp.426-433
• /
• 2002

In this paper, we have studied the images which have been reconstructed by using combination of images acquired by the variation of operating frequency. When inner images have been reconstructed, they have been superposed by the surface state effect. In this case, the images of the phase object can be enhanced by the contrast of inner images. In this experiment, there are two kinds of specimens, one is a reference block haying 1/4T, 1/2T, 3/4T side drilled holes as main run piping material 111 the steam generator in NPP(Neuclear Power Plant)s and the another is a part of a hemisphere type specimen having about 1-2㎜ distance gap. It has been shown that the two results of defect shapes have better than before in this processing and phase contrast grow about twice. And we have constructed the acoustic microscope by using a quadrature detector that enables to acquire the amplitude and phase of the reflected signal simultaneously Further more ore have studied the reconstruction method of the amplitude and phase images and the enhancement method of the defect images contrast.

• Korean Journal of Agricultural Science
• /
• v.39 no.3
• /
• pp.387-393
• /
• 2012

In the present study, ${\beta}$-glucanase-assisted extraction of starch from glutinous barley(Hinchal ssalbory) was investigated. ${\beta}$-glucanase was added to a coarse starch suspension obtained after wet milling in the starch extraction process. It was found that in the isolated starch with enzyme treatment, protein content was lower by 0.03%, compared to that with non-enzyme treatment. More importantly it was observed that the extraction yield of starch from enzyme treatment was found to be about 12% higher than the one from non-enzyme treatment (enzyme treated: 90.56%, non-enzyme treated: 78.46%). In order to elucidate this finding, the mass-balance determination of starch in each extraction step was carried out and found that the enzyme treatment might influence on the insoluble residues(R3 and R4 fractions) to hydrolyze ${\beta}$-glucan and other materials (e.g., mucilages etc.), thereby facilitated the separation of starch from it and a next filtration process. With a phase-contrast microscope it was observed that the isolated starch with enzyme treatment contained small starch granules more than the one with non-enzyme treatment and this might result in higher extraction yield observed with the former. In order to confirm this hypothesis, further experiments would be necessary.

• Journal of the Korean Society of Radiology
• /
• v.2 no.2
• /
• pp.23-30
• /
• 2008

X-ray microscopy with synchrotron radiation(SR) might be a useful tool for novel x-ray imaging in the clinical and laboratory settings. Microscopically, it enables us to observe detailed structure of animal organs samples with a great magnification power and an excellent resolution. The phase contrast mechanisms in image by X-ray are described. The phase-contrast X-ray imaging with SR from in-vivo and in-vitro mouse tail, rat nerve and rat lung were obtained with an 8 KeV monochromatic beam. The visual image was magnified using 10x microscope objective lens and captured using an digital CCD camera. The results showed more structural details and high resolution images with SR imaging system than conventional X-ray radiography system. The SR imaging system may have a potential for imaging in biological researches, material applications and clinical radiography.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.22 no.2
• /
• pp.134-139
• /
• 2012

Objectives: This study was conducted to study the analytical variability of A & B counting rules in counting using a phase contrast microscope airborne fibers collected on filters in man-made mineral or vitreous fibers (MMMFs) industries. Methods: Fibers in filters were counted using A & B rules of NIOSH Method 7400. Intra-counter and inter-counter variations by fiber type and density were obtained. The types of MMMFs analyzed were glass wool fiber, rock wool fiber, slag wool fiber, and refractory ceramic fibers. The densities of fibers classified were <20 $fibers/mm^2,$ 20 - <50 $fibers/mm^2$, 50 - <100 $fibers/mm^2,$ and ${\geq}100$ $fibers/mm^2,$ respectively. Results: Intra-counter relative standard deviations by rule A were 0.084, 0.102, 0.071 for glass wool fibers, rock wool fibers and refractory ceramic fibers, and those by rule B were 0.139, 0.120 and 0.142, respectively. Inter-counter relative standard deviations by rule A were 0.281, 0.296, 0.180 for glass wool fibers, rock wool fibers and refractory ceramic fibers, and those by rule B were 0.396, 0.337 and 0.238, respectively. Conclusions: Intra-counter variation was not different significantly among fiber types (p>0.05), but B rule variation for ceramic fibers approximately 2 times greater than corresponding A rule estimates, and intra-counter and inter-counter variations were higher in the low fiber density.