• Earthquakes and Structures
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• v.8 no.5
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• pp.1055-1067
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• 2015

A theoretical procedure to estimate spectral displacement of a hysteretic oscillator with bilinear stiffness excited by band-limited excitation is presented. The stochastic method of ground-motion simulation is combined with the random vibration theory to compute linear and nonlinear structural response. The response is obtained by computing the root-mean-square oscillator response using dissipation energy balancing by integrating over all energy levels of system weighting with the stationary probability density of the energy. The results are presented in a convenient form, and the accuracy of the procedure is assessed by comparison with results obtained with the time-domain method using the recorded data. The model shows little or no bias at the structural period of engineering interest.

• Nutrition Research and Practice
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• v.4 no.6
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• pp.486-491
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• 2010

Tight control of blood glucose is the most important strategy for the treatment of diabetes mellitus. Here, we investigated the beneficial effects of Welsh onion on fasting and postprandial hyperglycemia. Inhibitory activities of hot water extracts from the green stalk and white bulb, which are the edible portions of the Welsh onion, and the fibrous root extract against yeast ${\alpha}$-glucosidase were measured in vitro. To study the effects of Welsh onion on postprandial hyperglycemia, a starch solution (1 g/kg) with and without Welsh onion fibrous root extract (500 mg/kg) or acarbose (50 mg/kg) was administered to streptozotocin-induced diabetic rats after an overnight fast. Postprandial plasma glucose levels were measured and incremental areas under the response curve were calculated. To study the hypoglycemic effects of chronic feeding of Welsh onion, five-week-old db/db mice were fed an AIN-93G diet or a diet containing either Welsh onion fibrous root extract at 0.5% or acarbose at 0.05% for 7 weeks after 1 week of adaptation. Fasting plasma glucose and blood glycated hemoglobin were measured. Compared to the extract from the edible portions of Welsh onion, the fibrous root extract showed stronger inhibition against yeast ${\alpha}$-glucosidase, with an $IC_{50}$ of 239 ${\mu}g/mL$. Oral administration of Welsh onion fibrous root extract (500 mg/kg) and acarbose (50 mg/kg) significantly decreased incremental plasma glucose levels 30-120 min after oral ingestion of starch as well as the area under the postprandial glucose response curve, compared to the control group (P < 0.01). The plasma glucose and blood glycated hemoglobin levels of the Welsh onion group were significantly lower than those of the control group (P < 0.01), and were not significantly different from those fed acarbose. Thus, we conclude that the fibrous root of Welsh onion is effective in controlling hyperglycemia in animal models of diabetes mellitus.

• Journal of Life Science
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• v.31 no.3
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• pp.280-286
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• 2021

Oryzalin is a herbicide that disrupts the arrangement of microtubules by binding to tubulin, thereby blocking the anisotropic growth of plant cells. Microtubules and microfilaments are cytoskeleton components that have been implicated in plant growth through their influence on the formation of cell walls. Microtubules also play roles in the sedimentation of amyloplasts in the root tip columella cells; this sedimentation is related to gravity sensing and results in downward root growth in the soil for absorption of water and minerals. However, the orientation of microtubules changes depending on the level of ethylene in plant cells. A recent study reported that oryzalin stimulated ethylene production via 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ACC oxidase and caused a concentration-dependent inhibition of root growth and gravitropic responses. The aim of the present study was to investigate the possibility that oryzalin-induced inhibition might be recovered by the application of inhibitors of ethylene production, such as 10-4 M cobalt ions and 10-8 M aminoethoxyvinylglycine (AVG). The inhibition of root growth and gravitropic response was overcome by 10-20% by an 8 hr treatment with cobalt ions or AVG. These results suggest that ethylene levels could regulate root growth and gravitropic responses in Arabidopsis.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.1
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• pp.7-13
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• 2011

Accurate response analysis of long span bridges subjected to seismic excitation is important for earthquake hazard mitigation. In this paper, the performance of a typical four span continuous reinforced concrete bridge model subjected to asynchronous multiple seismic excitations at the supports is investigated in both the time and frequency domains and the results are compared with that from a relevant uniform support excitations. In the time domain analysis, a linear modal superposition approach is used to compute the peak response values. In the frequency domain analysis, linear random vibration theory is used to determine the root mean square response values where the cross correlation effects between the modal and the support excitations on the seismic response of the bridge model are included. From the two sets of results, a practical range of peak factors which are defined to be the ratio of peak and the root mean square responses are suggested for displacements and forces in members. With reliable practical values of peak factors, the frequency domain analysis is preferred for the performance based design of bridges because of the computational advantage and the generality of the results as the time domain analysis only yields results for the specific excitation input.

• Journal of Life Science
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• v.24 no.1
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• pp.8-13
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• 2014

The moringa (Moringa oleifera Lam.) plant is used as food and as an anti-allergic agent. In this study, we studied the inhibitory effect of moringa root extract on the expression of PMA-induced matrix metalloproteinase-9 (MMP-9), which is the main factor implicated in the invasion and metastasis of cancer cells in MCF-7 cells. At first, various moringa extracts were examined in the MCF-7 cells. Both moringa root extract and leaf extracts inhibited PMA-induced MMP-9 activity, but the root extract suppressed PMA-induced MMP-9 activity to a greater extent than the leaf extract. The moringa root extract also inhibited PMA-induced MMP-9 protein expression and cell invasion. According to RT-PCR, the treatment of the MCF-7 cells with moringa root extract decreased levels of PMA-induced MMP-9 mRNA expression, but not the expression of TIMP-1 and -2, indicating that moringa root extract prevents the transcription of MMP-9 in response to PMA. In addition, moringa root extract specifically suppressed the phosphorylation of ERK/JNK, but not p38. We suggest that moringa root extract abolishes MMP-9 activity/expression through ERK/JNK. In conclusion, moringa root extract suppressed PMA-induced MMP-9 activity/expression by inhibiting the phosphorylation of ERK/JNK in MCF-7 cells. These results indicate that moringa root extract may be a potential antimetastatic and anti-invasive agent. Future clinical research is needed on the anticancer properties of moringa root extract.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.1
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• pp.1-11
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• 2002

Root distribution was monitored in the root zone of corn fields on several soil series in central Illinois during three growing seasons in order to find the effect of soil series and tillage system on root growth. A minirhizotron technique was used to videotape each soil profile in weekly intervals to a depth of 75 cm under conventional tillage (CT) and no tillage (NT) systems of cultivation. Root distribution near soil surface generally increased during the early stages of the growing season, but declined as surface soil moisture was depleted in late summer. Even though root distribution was not significantly different between soil series in this experiment. differences in root distribution between soil series were associated with the increases in root-available water storage capacity. Root population in the top 30 cm of NT plots. where increased water infiltration rates and saturated flow of soil moisture into the subsoil, was generally higher than that of CT plots in Illinois corn fields. Foots appeared in the deeper layers later in the growing season, with root penetration into subsoil layers occurring as much as 2-3 weeks earlier on the NT plots than in CT plots. In conclusion, root distribution was significantly affected by the tillage systems, but not different by soil series.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.567-572
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• 2008

This paper's purpose is to improve determining of the critical response of curved bridge to multi-component seismic motion. There are several methods to combine responses by multi-component excitation response, 30%, 40% rules and square-root-of-sum (SRSS). These combination rules determine same value of critical response in straight bridges. However, each method has critical response value of different magnitude in curved bridges. Thus a study about critical response of curved bridges is required. This paper presents comparison critical responses value as each combination rule, 30%, 40% rules and SRSS on curved bridges with the different radiuses of curvature. This study was carried out by response spectrum analysis of OO IC steel box girder bridge using SAP2000. It is concluded as follows: 1) In curved bridges, 30% and 40% rules tend to underestimate the critical response relatively to SRSS. 2) When bridges have smaller radiuses than 100m, difference between SRSS and 30% or 40% rules let run errors up as radiuses of curvature decreased.

• Proceedings of the Korean Society of Crop Science Conference
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• 1989.02a
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• pp.98-99
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• 1989

• Proceedings of the Korean Society of Crop Science Conference
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• 1989.05a
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• pp.28-29
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• 1989

• Proceedings of the Korean Society of Crop Science Conference
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• 2018.10a
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• pp.220-220
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• 2018