• Journal of the Korean Society of Visualization
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• v.21 no.3
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• pp.93-100
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• 2023

The yeast Saccharomyces cerevisiae (S. cerevisiae) is considered an ideal eukaryotic model and has long been recognized for its pivotal role in numerous industrial production processes. Depending on the cell cycle phases, microenvironment, and species, S. cerevisiae varies in shape and has different sizes of each shape such as singlets, doublets, and clusters. Obtaining high-purity populations of uniformly shaped S. cerevisiae cells is crucial in fundamental biological research and industrial operations. In this study, we propose an acoustofluidic method for separating S. cerevisiae cells based on their size using surface acoustic wave (SAW)-induced acoustic radiation force (ARF). The SAW-induced ARF increased with cell diameter, which enabled a successful size-based separation of S. cerevisiae cells using an acoustofluidics device. We anticipate that the proposed acoustofluidics approach for yeast cell separation will provide new opportunities in industrial applications.

• Journal of Bio-Environment Control
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• v.17 no.1
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• pp.26-31
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• 2008

This experiment were conducted to investigate the response of growth and yield of potato after transplanting of plug seedlings 'Superior' and 'Dejima' produced at different plug cell size (105, 162, and 288) and photoperiod (8/16, 12/12, and 16/8, day/night) for 20 days in controlled plant growth system. Growth and relative growth rate of plug seedling 'Superior' was affected by plug cell size and photoperiod at 7weeks after transplanting. Tuber weight of 'Superior' was increased as cell size and photoperiod increased. That of 'Dejima' was highest in 105 cell and different with photoperiod. At 90 days after transplanting, tuber weight ($258.9{\sim}471.9\;g/plant) of 'Superior' was high in 105 and 162 cell size and 16/8 hr photoperiod. That ($278.2{\sim}428.0\;g/plant$) of 'Dejima' was high in 105 cell size, but was not different with photoperiod. The number of tuber per plant was $2.6{\sim}6.9$ of 'Superior' and $2.2{\sim}3.6$ 'Dejima'. Tuber number per plant was not significantly different with cell size and photoperiod. The large tuber over 80 g was $32.0{\sim}50.9%$ of 'Superior' and $41.0{\sim}56.7%$ of 'Dejima'. The large tuber in 'Superior' and 'Dejima' lowered as the cell size decreased. The large tuber of 'Superior' increased as photoperiod increased, but that of 'Dejima' was not differed. As the results, the optimal plug cell size and photoperiod of potato seedling is considered to be below 162 cell and over 12 hr of photoperiod.

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.210-217
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• 1999

Chemical oxygen demand (COD), phytoplankton cell number and chlorophyll-a concentration (Chl-a), sediment mean grain size and ignition loss were studied to determine their temporal trends in the study area. Historical data of COD, cell number and Chl-a were gathered from the late 1960s or early 1980s to 1997, and trends in temporal domain were obtained from a simple regression. Sediments for grain size and ignition loss (as organic contents in sediments) were sampled from the Chokchon macrotidal flat bimonthly from September 1990 to November 1996, and were analyzed using the decomposition method of time series analysis. In general, the first three data showed increasing trends based on regression analysis. The trends of sediment grain size fluctuated in a neutral pathway while those of ignition loss yielded no increasing pattern. In contrast with the suggestions from Ahn and Choi (1998) who reported a coarsening variation in sediment grain size to be a cause of the directional and remarkable changes of macrofaunal communities in this area, we could not find such a corresponding variation pattern from our samples. In diagnosing eutrophication, a paradoxical phenomenon was encountered between the trends in water column (COD, cell number and Chl-a) and sediment (ignition loss) data. In this paper, we inferred the possible processes that produce the discrepancy. Some explanations and biological responses to eutrophication were predicted and discussed.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.100.2-100.2
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• 2012

Surface texturing of crystalline silicon is carried out in alkaline solutions for anisotropic etching that leads to random pyramids of about $10{\mu}m$ in size. Recently textured pyramids size gradually reduced using new solution. In this paper, we investigated that texture pyramids size had an impact on emitter property and front electrode (Ag) contact. To make small (${\sim}3{\mu}m$) and large (${\sim}10{\mu}m$) pyramids size, texturing times control and one side texturing using a silicon nitride film were carried out. Then formation and quality of POCl3-diffused n+ emitter in furnace compare with small and large pyramids by using SEM images, simulation (SILVACO, Athena module) and emitter saturation current density (J0e). After metallization, Ag contact resistance was measured by transfer length method (TLM) pattern. And surface distributions of Ag crystallites were observed by SEM images. Also, performance of cell which is fabricated by screen-printed solar cells is compared by light I-V.

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.323-327
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• 1999

It was shown that brain-derived neurotrophic factors (BDNFs) secreted from human neuroblastoma cells can significantly improve the growth of the neurites of PC12 nerve cells. The addition of purified BDNFs elongated the neurites of PC 12 nerve cells two to three times more than the case where the addition was not made. The perfusion rate strongly affected the change of the size of human neuroblastoma cells because the cell size decreased as the perfusion rate increased. This could also influence the productivity of BDNF from the cells. It is also important to note that the BDNF production was decreased when the cell size was reduced. BDNF production rate also decreased at a fast perfusion rate in a smaller cell size. At the relatively fast perfusion rate of 18 ml/h, the ratio of apoptotic to necrotic cells dramatically decreased, which possibly caused the decrease of BDNF production. It has been proven that the secretion of BDNF from human neuroblastoma cells was a partially growth-related process by yielding 6.2$\times l0^{-8}/g$ of BDNF/cell/h of growth related parameter and $0.48{\times}l0^{-9}/g$ of BDNF/cell/h of nongrowth-related parameter in a growth kinetic model. In addition, it was also found that the perfusion rate played a very important role in controlling the cell death mechanism.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7351-7354
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• 2013

Background: Metabolic syndrome (MetS) is a multifactorial disease characterized by impaired glucose tolerance/diabetes, obesity, high triglyceride levels, low HDL levels, and hypertension. In this study we evaluate the relationship between tumor size and grade, and presence of the metabolic syndrome in patients with renal cell carcinoma. Materials and Methods: Between 2007-2013, radical nephrectomy was performed for 310 patients with renal tumors in our clinic and those with pathology reported renal cell carcinoma were enrolled and divided into two groups, with and without metabolic syndrome diagnosed on the basis of the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III) criteria. The relationship between tumor size and grade of the two groups (Fuhrman nuclear degree) was evaluated statistically. Results: The metabolic syndrome was found in 70 patients, with a mean age of 65.5 (40-87), as compared to 58.8 (31-84) years in the non-metabolic syndrome group. Tumor size over 7 cm was found in 54% and 33%, respectively, and tumor grade over Fuhrman 3 in 56% and 32% of patients. Patients with metabolic syndrome had significantly higher tumor size and grade (p<0.05). In the presence of hypertension, diabetes and high triglyceride levels, significant assocations were again observed (p<0.05). Tumor size and degree also increased with increasing body mass index but this was not statistically significant (p>0.05). Conclusions: Renal cancer is more aggressive in patients with metabolic syndrome. Lifestyle and risk factors were revealed to be significant influences in renal cancer patients.

• Applied Microscopy
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• v.29 no.3
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• pp.303-313
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• 1999

In this paper, five kinds of neurosecretory cells-light green (LG) cell, dark green (DG) cell, caudo-dorsal (CD) cell, blue green (BG) cell, and yellow (Y) cell- and neuropils in the cerebral ganglion of the African giant snail, Achatina fulica, were observed with an electron microscope. The following results were obtained. The LG cells are circular or ovoid in shape, and about $60{\mu}m$ in size. The nucleus and cytoplasm of the LG cell look light due to their electron-low density. Large granular chromatins are evenly developed in the karyolymph, where round nucleoli are also found. In the cytoplasm, electron -high dense round granules of $0.4{\mu}m$ in average size are crowded. The DG cells are ovoid in shape, and $50\sim20{\mu}m$ in size. These relatively electron-high dense cells were rarely found. In their cytoplasm, cell organelles such as rough endoplasmic reticulum and mitochondria are found together with electron -high dense round granules of $0.2{\mu}m$ in average size. The CD cells are ellipsoidal cells densely distributed in caudo-dorsal parts of the cerebral ganglion. They have large nuclei compared with the cytoplasm. The developed granular heterochromatins are observed in the karyolymph, and lots of small round granules of $0.12{\mu}m$ in average size in the cytoplasm. The 3G cells, rarely found around endoneurium of the cerebral ganglion, take the shapes of long ellipses. They look dark due to their electron -high density. In the cytoplasm, small round granules of $0.1{\mu}m$ in average size are found. The Y cells are the smallest among the neurosecretory cells($9\times6.6{\mu}m$ in size). They are found mostly between the medio-dorsal parts and the caudo-dorsal parts of the cerebral ganglion. In the cytoplasm, tiny round granules of $0.08{\mu}m$ in average size form a group. The neuropils are found in the middle of the cerebral ganglion. In the axon ending, round granules with electron -high density ($0.07\sim0.03{\mu}m$ in diameter) and lucent vesicles ($0.03{\mu}m$ in diameter) are found in large quantities. They are excreted in the state of exocytosome formed by the invagination of the limiting membrane of the axon ending.

• Journal of the Korea Society for Simulation
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• v.10 no.4
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• pp.11-20
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• 2001

In the IMT-2000 networks, the model of micro/pico cell is suggested for transmission of multimedia service. Hence, the efficient method is required for processing of mobile calls in micro/pico cell. In the central urban area, mobile calls may be dynamically increased because of many mobile users. And microcel]/picocell size has small size, handover calls will be more increased. Therefore, many of mobile calls is occurred at a cell in the central urban area, so channel requests for these calls will be increased in the call. In this paper, we propose a scheme, FTC(Fault Tolerant Channel allocation) which is the channel management method for hard handover and new call in a mobile cell of central urban area. When available channels in the cell are consumed, the FTC investigates channel states of neighbor cells in the RNC(Radio Network Controller) or BSC (Base Station Center), and provide available channel for mobile call. The ]no scheme is analyzed and compared with existing channel management method by simulation.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.165-178
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• 2000

In this study the effects of block distance have been investigated on the particle deposition efficiency in the collecting cell of two-stage electrostatic precipitator by numerical analysis. Particle trajectories have been changed by the electrostatic and inertial force of particle with the inlet velocity electrostatic number and particle diameter. The total deposition efficiency has a minimum value by the interaction between the effect of particle inertial force and electrostatic force in the collecting cell. The increase of block distance makes the total deposition efficiency decrease under the range of the particle size which has the minimum deposition efficiency. However beyond the range of particle size which has minimum deposition efficiency total deposition efficiency has no trend with the variation of block distance.

• Journal of Species Research
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• v.6 no.spc
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• pp.63-66
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• 2017

Three ciliate species, Frontonia schaefferi Bullington, 1939, Spathidium curiosum Foissner, 2016, and S. muscicola Kahl, 1930, were collected from freshwater and terrestrial habitats in Korea. Their morphology was investigated based on live observations and protargol impregnation. Frontonia schaefferi was characterized by a cell size of $89-112{\times}45-53{\mu}m$ (after protargol impregnation) and three vestibular kineties. Spathidium curiosum was characterized by a cell size of ca. $125{\times}25{\mu}m$ in vivo and the unusual shape of the extrusomes. Spathidium muscicola was characterized by a cell size of ca. $135{\times}40{\mu}m$ in vivo and four to six macronuclear nodules. These three species are new records for Korea.