• The Journal of Engineering Geology
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• v.25 no.3
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• pp.377-385
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• 2015

We constructed a model test apparatus to evaluate the dependence of the saturation velocity (V_s) in soils on rainfall intensity (I_R). The apparatus comprises a soil box, a rainfall simulator, and measuring sensors. The model grounds (60 cm × 50 cm × 15 cm) were formed by Joomunjin standard sand with a relative density of 75%. The rainfall simulator can control the rainfall intensity to reenact the actual rainfall in a soil box. Time Domain Reflectometer (TDR) sensors and tensiometers were installed in the soils to measure changes in the volumetric water content and matric suction due to rainfall infiltration. During the tests, the soil saturation was determined by raising the groundwater table, which was formed at the bottom of the soil box. [Please check that the correct meaning has been maintained.] The wetting front did not form at the ground surface during rainfall because the soil particles were uniform and the coefficient of permeability was relatively high. Our results show that the suction stress of the soils decreased with increasing volumetric water content, and this effect was most pronounced for volumetric water contents of 20%-30%. Based on a regression analysis of the relationship between rainfall intensity and the average saturation velocity, we suggest the following equation for estimating the saturation velocity in soils: V_savg (cm/sec) = 0.068I_R (mm/hr).

• Restorative Dentistry and Endodontics
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• v.23 no.2
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• pp.656-669
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• 1998

Hydrogen peroxide at high concentration during walking bleaching may cause damage to the tooth structure and to the surrounding periodontal tissues and may develop external root resorption. Clinically, It is so important to find a method of prevention or minimization of these complications. The efficacy of various chamber-irrigating agents to eliminate residual hydrogen peroxide after walking bleaching was examined and compared with water rinse in this study. Extracted human 46 premolars without any cementoenamel junction defects were treated endodontically and based with IRM to 1 mm below CEJ and totally bleached 3 times for each tooth with 30% hydrogen peroxide and sodium perborate. Upon completion of the 3rd walking bleaching procedure, the cervical portion and pulp chamber of each group of teeth were irrigated with catalase, 70% ethylalcohol, acetone, and distilled water. And then, a radicular hydrogen peroxide penetration was measured with spectrophotometer immediately after each bleaching and following treatment with each chamber-irrigating agents, and the significance of their eliminating efficacy of residual hydrogen peroxide was analyzed by Kruskal-Wallis test. The results were obtained as follows. 1. Cervical root penetration of hydrogen peroxide was increased as the bleaching procedure was repeated(P<.01). 2. The most effective irrigant that removed residual hydrogen peroxide was the catalase, and the least effective one was water rinsing (P<.01).; there was no significant difference between the acetone and ethanol group. 3. The Irrigation with antioxidant enzyme or water-displacement solutions can eliminate residual oxygen radicals from the pulp chamber effectively after walking bleaching. So, these agents can reduce adverse effects such as cervical external resorption and periapical inflammation and prevent residual $O_2$ from impeding composite resin polymerization, thus increase the bonding strength of composite resin. This, in turn reduces microleakage and discoloration of the esthetic restoration, extending its service-life.

• Journal of Biosystems Engineering
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• v.20 no.2
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• pp.162-172
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• 1995

The ventilation in greenhouse have been important for such as adjustment of temperature, supplying of the oxygen, prevention of the overhumidity, density adjustment of $CO_2$, discharge of harmfulness gas, etc. However, the general ventilation which had been used the quantitative control method in discharge of a property of air mechanism in greenhouse, and caused mainly in waste of the heating energy and growth obstacle of the vegetable. Therefore, this study was peformed to obtain more scientific ventilation method using by analysis and measurement of the isothermal lines according to opening of window ventilation in greenhouse, and the results are summarized as follows. 1. The ventilating amount was more influenced by rather opening amount of window than the ventilating time. 2. In window ventilation, the temperature in greenhouse was mostly changed within 5 minutes after ventilating not regard to the spot of opening, after about 10 minutes temperature became to equilibrium state under the respective ventilating conditions. 3. In opening of the skylight only, isothermal lines were complicated, therefore, a tall vegetable may be possible to damage by a cold-weather from the lower central port in greenhouse. 4. Isothermal lines were a tendency to simply in opening of a side window that may be more effective ventilation in kinds of the short vegetable. 5. In conditions of internal temperature>setting temperature>external temperature, a skylight can be suitable to open 10~20cm in order to the optimum ventilation in greenhouse. 6. In conditions of internal temperature>external temperature>setting temperature, opening of all the windows or both the side windows that can be suitable in order to obtain the optimum ventilation in greenhouse. 7. An effect of ventilation was the most excellent to open of all the windows or both the side windows, and it were also found orderly excellent to open of the side window and the skylight or the skylight only, to open of the side window only. 8. Temperature was varied as the equation of T=Tc+ (To-Tc)e-at, and the ranges of (a) values were limited within 0.34~0.68. 9. A variations of humidity were similar to that of temperature, s.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.1-14
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• 2007

The term, "food safety", has traditionally been viewed as a practical science aimed at assuring the prevention acute illnesses caused by biological microorganisms, and only to a minor extent, chronic diseases cause by chronic low level exposures to natural and synthetic chemicals or pollutants. "food safety" meant to prevent microbiological agents/toxins in/on foods, due to contamination any where from "farm to Fork", from causing acute health effects, especially to the young, immune-compromised, genetically-predisposed and elderly. However, today a broader view must also include the fact that diet, perse (nutrients, vitamins/minerals, calories), as well as low level toxins and pollutant or supplemented synthetic chemicals, can alter gene expressions of stem/progenitor/terminally-differentiated cells, leading to chronic inflammation and other mal-functions that could lead to diseases such as cancer, diabetes, atherogenesis and possibly reproductive and neurological disorders. Understanding of the mechanisms by which natural or synthetic chemical toxins/toxicants, in/on food, interact with the pathogenesis of acute and chronic diseases, should lead to a "systems" approach to "food safety". Clearly, the interactions of diet/food with the genetic background, gender, and developmental state of the individual, together with (a) interactions of other endogenous/exogenous chemicals/drugs; (b) the specific biology of the cells being affected; (c) the mechanisms by which the presence or absence of toxins/toxicants and nutrients work to cause toxicities; and (d) how those mechanisms affect the pathogenesis of acute and/or chronic diseases, must be integrated into a "system" approach. Mechanisms of how toxins/toxicants cause cellular toxicities, such as mutagenesis; cytotoxicity and altered gene expression, must take into account (a) irreversible or reversal changes caused by these toxins or toxicants; (b)concepts of thresholds or no-thresholds of action; and (c) concepts of differential effects on stem cells, progenitor cells and terminally differentiated cells in different organs. This brief Commentary tries to illustrate this complex interaction between what is on/in foods with one disease, namely cancer. Since the understanding of cancer, while still incomplete, can shed light on the multiple ways that toxins/toxicants, as well as dietary modulation of nutrients/vitamins/metals/ calories, can either enhance or reduce the risk to cancer. In particular, diets that alter the embryo-fetal micro-environment might dramatically alter disease formation later in life. In effect "food safety" can not be assessed without understanding how food could be 'toxic', or how that mechanism of toxicity interacts with the pathogenesis of any disease.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.257-262
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• 2006

This experiment was carried out to investigate the effect of hypoglycemic yogurt as a clinical test with person both who have diabetes and who don't have diabetes. Diabetes is a disease caused by unused and accumulated glucoses produced via the foods digestion due to the lack of insulin or lower tissue reaction to insulin. Patients with diabetes or complications of diabetes are on the rise annually. For the therapy and prevention of diabetes, a yogurt made from functional materials such as insulin-resistant FK-23 lactic acid bacteria, Pinitol, edible fiber which delays glucose-absorption, extract powder of glucose-absorption-inhibitory white bean and low-caloric Erythritol and banaba extract is effective for reduce or restrain the blood glucose levels. The blood glucose levels after a meal of non-diabetic persons were lower after drinking a hypoglycemic yogurt than they after drinking general yogurt. The blood glucose levels after a meal of 10 diabetic patients were checked after drinking the yoghurt. As a result, 19 mg/dL, 30 mg/dL, 31 mg/dL of blood glucose levels decreased in 30 min, 60 min and 120 min respectively after drinking the yogurt. Blood glucose inhibition rates of 80 % of the tested patients also decreased. The blood glucose level of the diabetic patients having drunk the yogurt for 30 days consistently decreased into 59 mg/dL in 120 min after a meal.

• The Journal of Korean Medicine
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• v.18 no.1
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• pp.72-81
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• 1997

The causes of stroke are presumed hypertension, atherosclerosis,. cardiac disease, diabetes mellitus and old age and risk factors of stroke are suggested hypertension, hyperlipidemia. obesity, smoking and drinking etc. Especilly, hypertension is one of the most important cause and risk factor of stroke, therfore without therapy hypertension leads to stroke. The frequence of hypertension is significantly higher in hemorrhage patients of intracranial hemorrhage and subarachnoid hemorrhage. Antihypertensive therapy has an impact not only on the primary prevention of stroke but also on stroke recurrence and the declining of stroke motality has been attributed to the widespread availability and use of antihypertensive therapy. The goals of antihypertensive therapy decrease the complications and motalitv of cardiovascular system and prevent the promoting arteriosclerosis. In this study, we observed the blood pressure change of cb-hemorrhagic patients with hypertension who were hospitalized from 1996. 3. 1 to 1997. 2 .26 in Wonkwang Oriental Hospital. These patients had no antihypertensive therapy and were supplied herb med(Jaum sikpoongtang, Chungrijagamtang, Gojinumja) in medication. Our results suggested as follows. 1. Systolic and diastolic average BP at admission is $150.71{\pm}15.61mmHg$ and $95.00{\pm}8.8mmHg$ and this is hypertension state defining WHO 2. During one week in admission, the blood pressure demostrated a marked declination by SBP 8.97mmHg and DBP 6.22mmHg. 3. During two week in admission, the declination of SBP was significant in paired t-test(p<0.05) but, the declination of DBP was non-significant in paired t-test. 4. The blood pressure during third and fourth weeks gradually declined but, non-significant in test. According to the above results, we suggested that the BP declination Was affected by $Jamyang{\cdot}Jaum$ prescriptions in acute stage of cerebral hemorrhage.

• Journal of Life Science
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• v.17 no.2 s.82
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• pp.211-217
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• 2007

The goal of this study is to investigate effects of temperature and co-chaperonin requirement for in vitro protein refolding assisted by E. coli chaperone GroEL under permissive and nonpermissive temperature conditions. In vitro protein refolding of two denatured proteins was kinetically investigated under several conditions in the presence of GroEL. Effects of temperature and GroES-requirement on the process of prevention of protein aggregation and refolding of denatured protein were extensively monitored. We have found that E. coli GroEL chaperone system along with ATP is required for invitro refolding of unfolded polypeptide under nonpermissive temperature of $37^{\circ}C$. However, under permissive condition spontaneous refolding can occur due to lower temperature, which can competes with chaperone-mediated protein refolding via GroEL chaperone system. Thus, GroEL seemed to divert spontaneous refolding pathway of unfolded polypeptide toward chaperone-assisted refolding pathway, which is more efficient protein refolding pathway.

• Journal of Life Science
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• v.20 no.11
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• pp.1603-1610
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• 2010

Fucoidans are sulfated fucosylated polymers from the cell wall of brown algae. We assessed the effects of Fucus evanescens fucoidan on ultraviolet-B (UVB)-induced expression of matrix metalloproteinase-1 (MMP-1) protein, mRNA, and promoter, and the phosphorylation of mitogen-activated protein kinases in vitro using an immortalized human keratinocyte cell line. Pretreatment with 10 and $100\;{\mu}g/ml$ fucoidan significantly inhibited UVB-induced MMP-1 protein, mRNA and promoter activity, compared to UVB irradiation alone. Extracellular signal regulated kinase activation was markedly inhibited by treatment with fucoidan, though c-JUN N-terminal kinase activity and p38 activation were only marginally affected by fucoidan. F. evanescens fucoidan may be a potential therapeutic agent for the prevention and treatment of skin photoaging.

• Journal of Life Science
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• v.27 no.7
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• pp.834-839
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• 2017

Propolis is a natural product collected from plants by honey bees product used extensively in traditional medicine for its antioxidant, anti-inflammatory, immunomodulatory and anti-cancer effects. Propolis exhibits a broad spectrum of biological activities because it is a complex mixture of natural substances. Ovarian cancer is the second most common newly diagnosed cancer from all cancers among women in Korea and the leading cause of death from gynecological malignancies. While most ovarian cancer patients initially respond to surgical debulking and chemotherapy, patients later succumb to the disease. Thus, there is an urgent need to test novel therapeutic agents to counteract the high mortality rate associated with ovarian cancer. In this study, we investigated the anti-cancer properties and the active mechanism of Australian propolis in human epithelial ovarian cancer A2780 cells. Our data revealed that propolis showed a cytotoxic activity in a dose-dependent manner. Flow cytometric analysis for cell cycle arrest and apoptosis using propidium iodide staning and annexin V-FITC indicated that propolis could induce cycle arrest in the G0/G1 phase and apoptosis in a dose-dependent manner on human epithelial ovarian cancer cells. These results suggest that the Australian propolis is potential alternative agent on ovarian cancer prevention and treatment.

• Proceedings of the Safety Management and Science Conference
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• 2011.04a
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• pp.731-746
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• 2011

The successful and sustainable growth of SMEs depends on their ability of strengthen their competitiveness in quality and cost and service more than anything else as a fundamental of operation. Among these key competitive factors of SMEs, quality is the most critical factor in manufacturing business fields. Because quality strongly influence cost and service performance on this manufacturing business field. There are many different ways to improve the quality performance but it needs proper management decision to choose the best way what can maximize outputs with minimum inputs. And it needs effective measurement methods and some indicators to analysis the quality performance properly. The quality cost is one of the simplest key indicators to measure the quality performance and the effectiveness of quality related management decisions. The major purpose of this study is to diagnose the categorized current level of actual quality cost of local SMEs to maximize their quality management effectiveness through comparing their level with others what's expressed in early studies. In this study, through survey on local SMEs, we found that their average annual quality cost ratio versus turnover - Total amount of annual quality cost divided by annual turnover - is around 3.69% excluded some SME's performances what have different quality control measures with others. And we found some results what corresponded with the early studies on the correlations between those categorized quality costs factors and some discrepancies between some of the literature model and the early case study results as follows. There were negative correlations between the Prevention costs and the External failure costs, and the Appraisal costs and the External failure costs, and there was positive correlation between the Appraisal costs and Internal failure costs same as early studies. But, we couldn't found any strong negative correlations between the Cost of control - Preventive costs & Appraisal costs - and the Cost of Failure of control - Internal & External failure costs -. It reveals not only the lack of effectiveness on their preventive or appraisal activities but also it can reveal there were so many effective ways to prevent the failure costs properly such as some innovative investment on Factory automation includes Error Proofing and more preventive actions to improve the effectiveness of the typical management methods likes CE (Concurrent Engineering), APQP (Advanced Product Quality Planning), FMEA (Failure Mode & Effect Analysis) etc.