• Journal of IKEEE
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• v.23 no.3
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• pp.947-953
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• 2019

The purpose of this paper is to explore an ASIC design for estimating sizes and concentrations of airborne micro-particles by the means of integrating, amplifying and digitizing electric charge signals generated by photo-sensors as it receives scattered photons by the presence of micro-particles, consisting of a pre-amplifier that detects and amplifies voltage or current signal from photo-sensor that generates charges (hole-electron pairs) when exposed to visible rays, infrared rays, ultraviolet rays, etc. according to the intensity of rays; a shaper for shaping the amplified signal to a semi-gaussian waveform; two discriminators and binary counters for outputting digital signals by comparing the magnitude of the shaped signal with an arbitrary reference voltages. The ASIC with the proposed architecture and functional blocks in this study was designed with a 0.18um standard CMOS technology from Global Foundries and the operation and performances of the ASIC has been verified by the silicons fabricated by using the process.

• Journal of Microbiology and Biotechnology
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• v.31 no.8
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• pp.1144-1153
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• 2021

A released exopolysaccharide (rEPS)-producing strain (LM187) with good acid resistance, bile salt resistance, and cholesterol-lowering properties was isolated from Sichuan paocai and identified as Leuconostoc mesenteroides subsp. mesenteroides. The purified rEPS, designated as rEPS414, had a uniform molecular weight of 7.757 × 10⁵ Da. Analysis of the monosaccharide composition revealed that the molecule was mainly composed of glucose. The Fourier transform-infrared spectrum showed that rEPS414 contained both α-type and β-type glycosidic bonds. ¹H and ¹³C nuclear magnetic resonance spectra analysis showed that the purified rEPS contained arabinose, galactose, and rhamnose, but less uronic acid. Scanning electron microscopy demonstrated that the exopolysaccharide displayed a large number of scattered, fluffy, porous cellular network flake structures. In addition, rEPS414 exhibited strong in vitro antioxidant activity. These results showed that strain LM187 and its rEPS are promising probiotics with broad prospects in industry.

• Korean Journal of Metals and Materials
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• v.49 no.1
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• pp.58-63
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• 2011

The grain size and growth direction of a directionally solidified turbine blade were evaluated by the initial nucleation condition at the start block of directional solidification. The initial nucleation condition was controlled by inserting a Ni foil on the directional solidification plate of the directional solidification furnace. Fine grains with good orientation were obtained in the faster cooling condition at the start block. The nucleus number was compared with the cooling rate of the start block by electron back scattered diffraction (EBSD). DSC (differential scanning calorimeter) analysis was performed to compare the melting point and undercooling for nucleation of the coarse nuclei and fine nuclei of the start block. The faster cooling condition at the start block showed more undercooling for nucleation and smaller size of nuclei which resulted in a fine grain with good orientation in the directional turbine blade.

• Progress in Medical Physics
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• v.15 no.1
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• pp.1-8
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• 2004

Patient dose verification is one of the most Important responsibilities of the physician in the treatment delivery of radiation therapy. For the task, it is necessary to use an accurate dosimeter that can verify the patient dose profile, and it is also necessary to determine the physical characteristics of beams used in intensity modulated radiation therapy (IMRT) The Beam Intensity Scanner (BInS) System is presented for the dosimetric verification of the two dimensional photon beam. The BInS has a scintillator, made of phosphor Terbium-doped Gadolinium Oxysulphide (Gd$_2$O$_2$S:Tb), to produce fluorescence from the irradiation of photon and electron beams. These fluoroscopic signals are collected and digitized by a digital video camera (DVC) and then processed by custom made software to express the relative dose profile in a 3 dimensional (3D) plot. As an application of the BInS, measurements related to IWRT are made and presented in this work. Using a static multileaf collimator (SMLC) technique, the intensity modulated beam (IMB) is delivered via a sequence of static portals made by controlled leaves. Thus, when static subfields are generated by a sequence of abutting portals, the penumbras and scattered photons of the delivered beams overlap in abutting field regions and this results in the creation of “hot spots”. Using the BInS, inter-step “hot spots” inherent in SMLC are measured and an empirical method to remove them is proposed. Another major MLC technique in IMRT, the dynamic multileaf collimator (DMLC) technique, has different characteristics from SMLC due to a different leaf operation mechanism during the irradiation of photon and electron beams. By using the BInS, the actual delivered doses by SMLC and DMLC techniques are measured and compared. Even if the planned dose to a target volume is equal in our experimental setting, the actual delivered dose by DMLC technique is measured to be larger by 14.8% than that by SMLC, and this is due to scattered photons and contaminant electrons at d$_{max}$.

• Applied Microscopy
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• v.24 no.3
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• pp.1-9
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• 1994

Pardosa astrigera possessed eight eyes arranged in three rows on the frontal carapace. A pair of small anterior lateral eyes (ALE) flanked each side by an anterior median eyes (AME) lay along the anterior margin that was situated on the anterior row of clypeus. The anterior lateral eye was composed of cornea, vitreous body, and retina. Cornea was made up mainly of exocuticle lining the cuticle. Lens in anterior lateral eye was biconvex type which bulged into the cavity of the eyecup. Outer and inner central region of lens were approximately spherical with radius of curvature $5.6{\mu}m$ and $12.5{\mu}m$, respectly. Vitreous body formed a layer between the cuticular lens and retina. They formed biconcave shape. Retina of the anterior lateral eyes was composed of three types of cells: visual cells, glia cells, and pigment cells. The visual cells were unipolar neuron, as were the receptor of the posterior lateral eye. But cell body was unique to the anterior lateral eyes. They were giant cell, relatively a few in number, and under the layer of vitreous bodies. Each visual cell healed rhabdomeres for a short stretch beneath the cell body. Rhabdomes were irregulary pattern in retina and electron dense pigment granules scattered between the rhabdomes. Glia cell situated at the cell body of visual cell and glia cell process reached to rhabdomere portion. Below the rhabdome, tapetum were about $30{\mu}m$ distance from lens, which composed of 4-5 layers. It was about $25{\mu}m$ length that intermediate segment of distal portion of visual cell. Electron dense pigment granules between the intermediate segment were observed.

• Journal of the Mineralogical Society of Korea
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• v.17 no.3
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• pp.221-233
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• 2004

Mineralogical characteristics and genesis of phlogopite in the talc deposits of the chungnam area were studied. Mica is one of the major impurity of talc ores in the study area. Talc-related micas show typical phlogopite composition, whereas talc-unrelated micas show wide compositional variations between biotite and phlogopite. Phlogopite mainly occurs in the black-wall type zone, especially in the nodular talc ores near the outer part of talc ore bodies. Interleaving textures of phlogopite and chlorite are easily observed under the optical microscope and back-scattered electron images. Interleaving textures of phlogopite and talc are observed also. Examination of the phlogopite by transmission electron microscope reveals that 14 $\AA$ layers of chlorite are randomly interlayered within the 10 $\AA$ layers of phlogopite, which suggests that the genesis of phlogopite is closely related to chlorite. Considering the occurrence and mineralogical characteristics of phlogopite, and the possible origin of K for the formation of phlogopite, phlogopite of the study area was formed by interaction between talc ore body and hydrothermal solution containing sufficient K at the late stage of talc formation. K might be introduced from the granitic gneiss at the contact zone between the talc ore body and the granitic gneiss under favorable structural condition for the potash metasomatism.

• Applied Microscopy
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• v.17 no.1
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• pp.98-114
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• 1987

Degranulation of the rat peritoneal mast cell induced by intraperitoneal injection of horseradish peroxidase(HRP) was studied using light and electron microscopes. 1. Rat peritoneal mast cells in the Tyrode's buffered salt solution injected control group did not show any particular morphological changes following the specified time course. 2. Under the light microscope, the majority of mast cells observed 10 minutes after HRP injection were nearly the same as those of the control group. However, after 30 minutes, granule densities or staining properties of certain cells began to decrease and these appearances increased gradually until 12 hours after injection, at which time small groups of granules being stained pale-red or pink with toluidine blue were easily identified in the cytoplasm of many cells, and numerous extruded granuleg were scattered around these cells. 3. In the mast cells representing the early stage of degranulation induced by HRP, the electron densities of certain granules decreased as the size enlarged, and perigranular cavities were formed by perigranular membrane expansion. As a result, a thin cytoplasmic septum was formed between the expanded perigranular membrane and the cytoplasmic membrane in the cell periphery, and fusion of the adjacent perigranular membranes was observed in the inner side of the cell. 4. In some mast cells, one or two changes in the peripheral cytoplasmic septum could be seen. One was a focal rupture of the peripheral septum and the other was the formation of a saccule containing one or more vesicles. This saccule was thought to be used for granule-extrusion site and/or material absorptive apparatus judging from the morphological characteristics. 5. As the degranulation proceeded, the granule was extruded from the cell after partial rupture of the peripheral cytoplasmic septum. This phenomenon proceeded to-ward the inner side of the cell through the fused perigranular cavities, and consequently several distinct cavities containing a few unextruded membrane-free granules were formed throughout the cytoplasm after 12 hours. As a rule, the granule-extrusion sites were relatively fewer while the cytoplasmic cavities resulting from degranulation were more numerously observed. Thus, it was thought that the granule-extrusion sites tended to be restricted in the HRP-induced degranulation.

• Journal of the Korean Ceramic Society
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• v.38 no.10
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• pp.914-920
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• 2001

The grain orientation distribution and grain boundary characterization of $ZrB_2$-ZrC composites sintered by a SPS(Spark Plasma Sintering) method, a new sintering technique were analyzed by the EBSP technique and then their crystallographic results have been compared with those of a sintered specimen using a PLS(Pressureless Sintering) method. In the $ZrB_2$-ZrC composite manufactured by SPS, (0001) planes of $ZrB_2$ were oriented in the direction normal to the specimen surface. In the case of PLS, those of $ZrB_2$ were oriented normal to the electron beam. In both cases of PLS and SPS, ZrC grains had the randomly oriented grain structure. The grain boundary characterization showed that low angle grain boundaries in the PLS and SPS processed materials constituted about 10% and 8% of the total number of boundaries, respectively, represented the only slight difference between the proportion of low angle grain boundary. However, in the distribution of CSL(Coincident Site Lattice) boundaries, it was shown the higher proportion of CSL boundaries with $\Sigma$ 3,5,7,9, 11 in the SPS processed material.

• Parasites, Hosts and Diseases
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• v.23 no.2
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• pp.269-284
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• 1985

The metabolism of Entamoeba histolytica would be affected by various environmental factors, and alteration of the environment was known to afEect the fine structure of 5. histolytica. The present study was designed electronmicroscopically to investigate the ultrastructure and enzyme activities in the aEonic and conventional strains of 5. histolytica. The trophozoites of axenically cultivated HK-9 strain and conventional YS-27 and YS-49 strains of 5. histolytica were collected and liKed with 4% paraformaldehyde/0.1M cacodylate buffier(pH 74), After washing them by centrifugation, 1% warm agar was added in the sediment. Solidified agar with the trophozoites was cut into $lmm^3$ cubes, and incubated in the various substrates to observe enzyme activities. Then, the specimen was post-fixed with 3% glutaraldehyde/0.1M cacodylate buffer (PH 7.4) and 1% osmium tetroBide/0.1M cacodylate buffier (pH 7.4) , dehydrated in ascending ethanol series and embedded in epoxy resin. These were sectioned on an ultramicrotome and observed with a transmission electronmicroscope. The procedures for the observation of the fine structure were same as the above, except for the incubation in the substrate. The sections were stained with uranyl acetate and lead citrate. For the observation of the surface of the amoebae, scanning-electronmicroscopy was carried out. The results obtained in the present study are summarized as follows: 1. The fuzzy coat around double-layered plasma membrane of 5. histolytica was more irregularly and densely distributed in the conventional strains (YS-27, YS-49 strains) than in the axonic strain (HK-9 strain). 2. The endosomes, button bodies and chromatin material were surrounded by a double-layered nuclear membrane having scattered nuclear fores. The paranuclear body, mono- or double-layered vacuoles, vacuolar membrane whorls, rosette-like cylindrical bodies, aggregation of cylindrical bodies and helical bodies were found in the cytoplasm of the amoebae. Helical bodies and glycogen granules were generally abundant, while a few smooth endoplasmic reticula were observed in the cytoplasm. 3. Alkaline phosphatase activity was mainly demonstrated in the plasma membrane, limiting membranes of vacuoles and smooth endoplasmic reticula. ATPase activity was observed in the nucleus, limiting membranes of vacuoles and vacuolar membrane whorls. 4. Acid phosphatase activity was commonly demonstrated in the limiting membranes an contents of vacuoles, Iysosome-like organelles, plasma membrane and the button bodies in the nucleus. The activity was more weakly demonstrated in the HK-9 strain than in the other conventional strains of 5. histolytica. No peroBidase activity was observed in the amoeba strains employed in the present study. 5. With a scanning electron-microscope, no distinct structural differences were observed between the amoeba strains. All the trophozoite forms of the amoebae showed crater-like depressions and rugged features on the outer surface.

• Membrane Journal
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• v.12 no.2
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• pp.97-106
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• 2002

Small angle light scattering (SALS) and field emission scanning electron microscope (FE-SEM) have been used to investigate the light scattering patterns with time evolved during water vapor quenching (relative humidity of 53 (${\pm}3)%$ at $26^{\circ}C$ of polysulfone (PSf)/NMP/Alcohol and chlorinated poly(vinyl chloride) (CPVC)/THF/Alcohol, respective1y. Time dependence of the position of the light scattering maximum was observed at PSf dope solutions, confirming spinodal decomposition (SD), while CPVC dope solutions showed a decreased scattered light intensity with an increased q-value, indicating nucleation & growth (NG). For the each system, domain growth rate in the intermediate and late stage of phase separation decreased with increasing the number of carbon of alcohol used as additive (non-solvent). Also, in the early stage for SD, the scattering intensity with time was in accordance with Cahn's linear theory of spinodal decomposition, regardless of types of non-solvent additive. Also, the size scales obtained by SALS were mutually compared to domain sizes gained by FE-SEM measurement. These observations of scattering pattern were much clearly observed for the 20PSf/70NMP/10n-butanol (w/w%) and agreed with the theoretical predictions for scattering patterns of each stage like the early, the intermediate, and the late stage of SD type phase separation. As the scattering maximum was observed at the larger angles (larger q) in the order of n-butanol > n-propanol > methanol > no alcohol, the pore size of final morphology decreased.