• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2000년도 학술발표회 발표논문집
• /
• pp.365-370
• /
• 2000

Sea dike construction for the tidal flat reclamation works in estuary and coast may change the characteristics of tidal motion and wave conditions in the region. In turn, a new hydraulic condition provides the impacts on sediment transport pattern and forms a new morphological environment. Also, morphological changes during the closure works of sea dike are closely related with a safy of sea dike. Therefore, the prediction of morphological changes is required secure the safe closure work and the economic design of sea dikes. To investigate morphological changes due to sea dike construction, hydrodynamic changes of tides and waves have to be evaluated, then sediment transport and sea bottom changes are computed. Mathematical modelling is required for representation of interrelation of tidal motion, wave and sediment transport. In this study, numerical model MORSYS is applied to compute the hydrodynamics and morphological changes around the closure gap for Saemankuem dike. This model allows a flexible integration of the module for waves, currents, sediment transport and bottom changes.

• Bulletin of the Korean Chemical Society
• /
• 제32권8호
• /
• pp.2661-2665
• /
• 2011

We studied the effect of structural and morphological changes on the conductivity of a stretched conducting polymer film. To improve the poor processability of polyaniline, we used dodecylbenzenesulfonic acid as both a surfactant and a dopant during emulsion polymerization, followed by blending with high-impact polystyrene. UV-Vis/NIR spectra were obtained to observe conformational changes, and SEM and AFM were used to investigate morphological changes. FT-IR dichroism was applied to determine the microscopic orientation, and XRD patterns were obtained for quantitative crystallinity analysis. The electrical conductivity (${\sigma}_{\parallel}/{\sigma}_{\perp}$) was measured as a function of draw ratio. We found a clear correlation between morphological changes and (${\sigma}_{\parallel}/{\sigma}_{\perp}$), especially at the stretching limit. The conductivity of the films can be modified according to the desired application by controlling their structure and morphology.

• 한국동물생명공학회지
• /
• 제37권1호
• /
• pp.42-47
• /
• 2022

This study aimed to determine whether hormonal hypersecretion could cause morphological problems in the mouse vagina and affect the ovaries and nearby extra uterine organs. All mice were synchronized to estrus before the experiment. Then human chorionic gonadotropin (hCG), progesterone, and testosterone were continuously administered for about 6 days to maintain hormone hypersecretion, and then morphological changes were analyzed, and Matrix metalloproteinases (MMPs) activity and Casp-3 expression were evaluated. As a result of the analysis, in the case of hCG, the morphological change did not show a significant difference from the vagina of normal estrus. In the case of progesterone, changes were observed in the mucosa zone and basal membrane, and it was confirmed that the activity of MMPs was increased in squamous epithelium cells. On the other hand, in the case of testosterone, overall changes in vaginal tissues were observed, and MMPs activity was increased to a very high level in all sections. The expression of Casp-3 was also the highest compared to other groups. Therefore, as a result of this study, it is thought that hormone hypersecretion affects the morphological changes of the vagina other than the ovaries and uterus and induces the activity of MMPs to cause morphological degeneration of tissues.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2000년도 춘계학술대회논문집B
• /
• pp.531-534
• /
• 2000

The objective of this investigation is to find effects of the pulsatile flow on the morphological changes of the endothelial cell(E.C.) in blood vessel. The shear flow experiment system is used to get the morphological changes of the E.C. The shapes of E.C. are simulated by the cosine curves and computer simulation is used to calculate the pressure and shear stress fields on the E.C. The inlet boundary condition is given from the measured velocity data of femoral artery. The endothelial cells reduce their heights in the flow field so as to reduce the pressure and wall shear stress on the surface. As the exposed time increases, the shear stress and pressure on the E.C. are reduced under the pulsatile flow. The shear stresses on the cell surface show the minimum values during the deceleration phase.

• 대한기계학회논문집B
• /
• 제22권11호
• /
• pp.1521-1529
• /
• 1998

The objective of this study is to investigate the effects of the hemodynamics on the morphological changes of the human endothelial cells due to the blood flow by in vitro experiment and computer simulation. The morphological changes of the endothelial cells due to the t10w shear stress were observed in the laminar t10w chamber as a function of the exposure time. The observed shapes of the endothelial cells are used to the model shapes of the endothelial cells for numerical study and the pressure and the wall shear stress variations around the endothelial cells are calculated from the numerical results. The endothelial cells elongate along the t10w direction and lessen their heights in the flow field to reduce the pressure and the wall shear stress on the surface.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2004년도 학술발표회
• /
• pp.557-562
• /
• 2004

A surface-piercing barrier model is presented for understanding morphological development in the sheltered region and investigating the main factors causing the severe accumulation. Surface-piercing structures like vertical barriers, surface docks and floating breakwaters are recently favored from the point of view of a marine scenario since they do not in general partition the natural sea. The numerical solutions are compared with experimental data on wave profiles and morphological change rates within a rectangular harbor of a constant depth protected by surface-piercing thin breakwaters as a simplified problem. Our numerical study involves several modules: 1) wave dynamics analyzed by a plane-wave approximation, 2) suspended sediment transport combined with sediment erosion-deposition model, and 3) concurrent morphological changes. Scattering waves are solved by using a plane wave method without inclusion of evanescent modes. Evanescent modes are only considered in predicting the reflection ratio against the vertical barrier and energy losses due to vortex shedding from the lower edge of plate are taken into account. A new relationship to relate the near-bed concentration to the depth-mean concentration is presented by analyzing the vertical structure of concentration. The numerical solutions were also compared with experimental data on morphological changes within a rectangular harbor of constant water depth. Through the numerical experiments, the vortex-induced flow appears to be not ignorable in predicting the morphological changes although the immersion depth of a plate is not deep.

• BMB Reports
• /
• 제42권9호
• /
• pp.574-579
• /
• 2009

The regulatory effects of honokiol on the cellular responses of macrophages and monocytes were evaluated. Specifically, we investigated the effects of honokiol with respect to lipopolysaccharide (LPS)-induced cytotoxicity, LPS- or phorbol-12-myristate-13-acetate (PMA)-mediated morphological changes, and relevant events (FITC-dextran-induced phagocytic uptake). Honokiol blocked the LPS-induced cytotoxicity of RAW264.7 cells in a dose-dependent manner. In addition, honokiol appeared to block the production of cytotoxic cytokines such as interleukin (IL)-$1{\beta}$ and tumor necrosis factor (TNF)-$\alpha$, nitric oxide (NO), and reactive oxygen species (ROS). Moreover, honokiol strongly prevented the morphological changes in RAW 264.7 and U937 cells that were induced by LPS and PMA. The surface levels of marker proteins, which are up-regulated under the morphological changes of RAW264.7 and U937 cells, were also diminished. The data presented here strongly suggest that the honokiol modulates various cellular responses managed by macrophages and monocytes.

• 한국해양공학회지
• /
• 제32권3호
• /
• pp.192-201
• /
• 2018

In this study, a qualitative evaluation of the morphological changes in the seabed surrounding Jinwoo-Island due to the construction of the new Busan port were determined through a numerical simulation. Various scenarios for the discharge of the Nakdong river estuary dam and construction stage of the new Busan port were established and utilized for an indirect and qualitative investigation through simulation using the numerical model implemented in this study. It was concluded through a qualitative study that the morphological changes in the seabed surrounding Jinwoo-Island were typical estuary seabed changes due to the discharge of the Nakdong river estuary dam and waves from the open sea. The effects from the construction of the new Busan port were relatively small.

• The Korean Journal of Physiology and Pharmacology
• /
• 제19권3호
• /
• pp.211-218
• /
• 2015

The present study showed that silymarin, a polyphenolic flavonoid isolated from milk thistle (Silybum marianum), inhibited lipopolysaccharide (LPS)-induced morphological changes in the mouse RAW264.7 macrophage cell line. We also showed that silymarin inhibited the nuclear translocation and transactivation activities of nuclear factor-kappa B (NF-${\kappa}B$), which is important for macrophage activation-associated changes in cell morphology and gene expression of inflammatory cytokines. BAY-11-7085, an NF-${\kappa}B$ inhibitor, abrogated LPS-induced morphological changes and NO production, similar to silymarin. Treatment of RAW264.7 cells with silymarin also inhibited LPS-stimulated activation of mitogen-activated protein kinases (MAPKs). Collectively, these experiments demonstrated that silymarin inhibited LPS-induced morphological changes in the RAW264.7 mouse macrophage cell line. Our findings indicated that the most likely mechanism underlying this biological effect involved inhibition of the MAPK pathway and NF-${\kappa}B$ activity. Inhibition of these activities by silymarin is a potentially useful strategy for the treatment of inflammation because of the critical roles played by MAPK and NF-${\kappa}B$ in mediating inflammatory responses in macrophages.

• 대한수의학회지
• /
• 제37권2호
• /
• pp.253-262
• /
• 1997

To investigate morphological changes in the endocrine pancreas of chicken after pancreatic duct ligation, experimental animals were subdivided to control, 12 hours, 1 day, 2 days, 4 days, 7 days and 10 days groupes and all of three pancreatic ducts of chicken were ligated by surgical procedure and then the morphological changes were observed. In pancreatic islets, the vacuolation and invasion of connective tissue were occurred in all experimental groups and dissociation of pancreatic islets was detected in 4 days after pancreatic duct ligation and hold out to 10 days. The peak of the morphological changes in pancreatic islets was detected in 4 days after pancreatic duct ligation. In the results of immunohistochemical methods against glucagon, insulin, somatostatin and bovine pancreatic polypeptide(BPP), the number of immunoreactive pancreatic islets were decreased but the size increased with time, so the number of immunoreactive cells in each pancreatic islets were increased. Glucagon-immunoreactive cells were not changed but insulin-immunoreactive cells were decreased with time(p<0.05). BPP-immunoreactive cells were increased in 2 days after pancreatic duct ligation and then decreased with time(p<0.05). Somatostatin-immunoreactive cells were increased with time(p<0.05) in dark islets.