• Korean Journal of Veterinary Research
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• v.28 no.2
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• pp.271-277
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• 1988

In order to study the marked variation of red blood cell sedimentation rate in some species of animals, the packed cell volume, volume percentage of erythrocytes in whole blood, was reshuffled of 20%, 40% and 60% using heteroplasma of chicken and goat, and the red blood cell sedimentation rate was measured in Westergren tubes at $27{\pm}1^{\circ}C$ and $8{\pm}1^{\circ}C$. The results obtained were summarized as follows: 1. The values of packed cell volume(PCV) of goat and chicken were $40.7{\pm}4.1%$ and $30.2{\pm}2.2%$ respectively. 2. The sedimentation rates of reshuffled red blood cell were settled faster at lower PCV than higher PCV, i.${\acute{e}}$. there was a reverse relationship between the sedimention rate and PCV. 3. Red blood cells of chicken settled quickly, where as those of goat settled very slowly. Chicken red blood cell sedimented rapidly even in goat plasma, and goat red blood cell sedimented slowly in chicken plasma. These findings indicate that the plasma is not the only factor determining the rapid red blood cell sedimentation rate of chicken. 4. The sedimentation rate of reshuffled red blood cell of chicken and goat were accelerated at higher temperature than lower temperature.

• Journal of Plant Biotechnology
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• v.40 no.3
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• pp.141-146
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• 2013

This study was conducted to examine suspended embryogenic cells growth with days of culture, effects of various kinds/concentrations of osmoticum for induction of somatic embryos (SEs), following somatic embryos germination or plantlet regeneration. The proliferation pattern of embryogenic cells in suspension culture is characterized by settled cells volume (SCV) increased with the duration of culture with marked the maxium of SCV (10.1 ml) in 18 days of culture, however the SCV of cells gradually decreased after that. In comparison of kinds/concentrations of osmoticum on somatic embryo induction, the highest induction number (352.3/g FW) of the SE was showed in 0.2 M sucrose, in addition, we also observed some effects with treatments of 0.2 M maltose (203.7) and 0.3 M maltose (193.7), respectively. However, no somatic embryos produced in treatments of 7.5% PEG plus 0.15 M sucrose or maltose. In comparison of germination efficiency of SEs which occurred from the treatments of various kinds/ concentrations of osmoticum, the highest induction frequency of cotyledon (25.2%) was obtained from SEs that produced 0.3 M maltose, however, the best occurrence rates of hypocotyl (39%), radicle (30.3%) and plantlet regeneration (3.5%) were observed from the 0.2 M sucrose treatment, respectively.

• Journal of Korea Water Resources Association
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• v.46 no.2
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• pp.139-153
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• 2013

For analyzing shallow-water flows over the uneven bottom, the HLLL scheme and the divergence form for bed slope source term (DFB) technique, respectively were applied to the flux gradient and the bottom gradient source terms in a finite-volume model for the shallow water equations. And also the model incorporated the volume/free-surface relationship (VFR) to consider the partially submerged cells (PSC). It was identified that a simpler version of the weighted surface-depth gradient method in the MUSCL was equivalent to the original one in the accuracy for 1D steady flows. It was verified that the flux gradient term and the bottom gradient source term were well-balanced exactly by the VFR for the 1D PSC. The VFR for the triangular PSC settled the problem which the governing equations were not well-balanced by the DFB technique for the 2D PSC. There were good agreements in simulations and experiments for 2D dam-break flows over a triangular sill and a round bump. In addition, the partial dam-break flow was successfully simulated for flooding of roughnesses in an irregular bottom as well as a sloping one. Therefore, this model is expected to be applied to the real river with uneven topography.

• Journal of Preventive Medicine and Public Health
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• v.10 no.1
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• pp.134-137
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• 1977

The most efficient method for reducing the organic content of dilute liquid waste is by aerobic-biological treatment. Basically, the organisms responsible for treatment possess the ability to decompose complex organic compounds and to use the energy so liberated for their bodily functions: reproduction, growth, locomotion and so on. That part of organic matter used to produce energy is converted to the essentially stable end products of carbon dioxide, water and ammonia, while the remainder is converted to new cells which can be settled and thus removed from the liquid before the waste is discharged to the receiving body water. Oxygen must be supplied continuously during the aerobic process. In the field of sewage treatment the Warburg respirometer is used mainly for the measurement of the oxygen uptake of samples. In this experiment the Warburg constant volume respirometer was used to determine the oxygen uptake by bacteria in the presence of various glucose concentrations. The rate of oxygen uptake by the bacteria was expressed as the respiratory quotient. The result indicated that the oxygen uptake was proportional to the glucose concentration. The expecting equation of the regression line was Y=7.7+0.12X where Y: respiratory quotient, ${\mu}l.\;O_2$ taken up/mg. dry wt. bacterium/hr. X: concentration of glucose, mg/l

• Journal of Korean Society on Water Environment
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• v.23 no.6
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• pp.807-813
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• 2007

Settling velocity is one of major parameters determining algal biomass in water quality modeling. In this study, the settling velocity of phytoplankton was measured in reservoir and stream sites of the Nakdong River, Korea. Settling velocities of various phytoplankton species were determined by measuring algal cell biomass settled in a sedimentation cylinder. Mean settling velocities were $0.22m\;day^{-1}$ in reservoir sites and $0.33m\;day^{-1}$ in stream sites, which were relatively higher compared with other default values suggested by water quality models (e.g. $0.1m\;day^{-1}$ in CE-QUAL-W2). The lower settling velocity in reservoirs than in stream implies the adaptation of phytoplakton to low turbulence in lentic environments. Cyanobacteria showed lower settling velocity ($0.2m\;day^{-1}$) than diatoms ($0.3m\;day^{-1}$), and this phenomenon may have resulted from buoyancy mechanisms of cyanobacteria. Cell volume did not show a significant correlation with settling velocity in this study, implying that conformation factors of colonies or other factors had large effects on settling velocity of algal cells as well as cell size. The result of this study may suggest proper coefficients of settling velocity of phytoplankton in the calibration of water quality model.