• Title/Summary/Keyword: controlled-stress

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A Study on Effects of Oil Contaminated Soil on the Growth of Plant (유류오염토양이 식물식생에 미치는 영향에 관한 연구)

  • Choi, Min-Zoo;Kim, Joo-Young;Kim, Jung-Hoon;Choi, Sang-Il
    • Journal of Soil and Groundwater Environment
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    • v.15 no.1
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    • pp.50-56
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    • 2010
  • Oil contamination soil has been one of the most environmental social issues for decades in the inside and outside of country. The law of soil environmental preservation was carried out in the 1990s and the government controlled not only soil environment management and the remediation of contaminated soil but also promoted the development of remedial technology and cleanup business of contaminated soil by national policy. In addition to agriculture areas, the main oil contaminated sites are a gas station, oil reservoir, petro-chemical complex, site of railway carriage base and military camp. The contamination-frequency of agriculture area and effect sites are low but it has significantly important area on account of producing food for human beings. Therefore, we should be concerned about oil contamination damage of agriculture area. The oil contamination damage of agriculture area influenced drop of birth and breeding since the oil directly adheres to seeds and farm products even diffusion of contaminated soil to cultivation area. The studies of the crops and the food vegetation has not enough detailed data caused by the incident of oil contamination. This study investigated the effect of oil in germination and growth of selected plant seeds. In this study, we try to verify whether the oil contamination by accidents on farmland influenced the damage of farm produce and the mutual relation both oil contaminated soil or the vegetation of crops. The impact of oil on plant development was followed by phytotoxicity assessments. The plants exhibited visual symptoms of stress, growth reduction and perturbations in developmental parameters. The increase of the degree of pollution induced more marked effects in plants, likely because of the physical effects of oil. The relationships between the phytotoxicity contents of plants and growth reduction suggest a chemical toxicity of fuel oil. In addition, while cleaned up the contaminated soil under the standard of contaminated soil we examined it was suitable for region standard and it may have practical possibility for fill material of construction of afforestation and molding soil of landfill.

Characteristics of hypoxia-induced ANP Secretion in Perfused Beating Atria (허혈성 자극에 의한 심방이뇨 호르몬 분비 반응의 특성)

  • Kim, Kong-Soo;Kim, Min-Ho;Kim, Chang-Gon;Kim, Suk-Kee;Cho, Kyung-Woo;Cui, Xun
    • Journal of Chest Surgery
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    • v.33 no.5
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    • pp.398-406
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    • 2000
  • Background: Cardiac atrium is an endocrine gland secreting a family of natriuretic peptides. The secretion of atrial natriuretic peptide(ANP) had been shown to be controlled by variable factors. The change in atrial dynamics have been considered as one of the most prominent stimuli for the stimulation of ANP secretion. Hypoxic stress has been shown to increase cardiac ANP secretion. However, the mechanism by which hypoxia increases ANP secretion cardiac ANP secretions. However, the mechanism by which hypoxia increases ANP secretion has not to be defined. Therefore, the purpose of the present study was tow-fold: to develop a protocol to defined the effect of hypoxia on ANP secretion in perfused beating rabbit atria and to clarify the mechanism responsible for the accentuation by hypoxia of ANP secretion. Material and Method: Experiments have been done in perfused beating rabbit atria. ANP was measured by radioimmunoassay. Result: Hypoxic stimulus with nitrogen decreased atrial stroke volume. The decrease in atrial stroke volume recovered basal level during the period of recovery with oxygen. ANP secretion and the concentration of perfusate ANP in terms of extracellular fluid(ECF) translocation which reflects the rate of myocytic release of ANP were increased by hypoxia and returned to basal levels during the recovery. Changes in ECF translocation paralleled by hypoxia and returned to basal levels during the recovery. Changes in ECF translocation paralleled to that of atrial stroke volume. At the start of recovery in atrial storke volume, ECF tranalocation incrased for several minutes. The above responses were stable and reproducible. Glibenclamide treatment prevented the recovery in atrial stroke volume. Increments by hypoxia of ANP secretion and ANP concentration were suppressed by glibenclamide. Conclusion: These results indicate that hypoxia incrased atrial myocytic ANP release and that the mechanism responsible for the accentuation is partially related to the change in K+ATP channel activity.

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Cross-sectional and Comparative Study between First Attack and Reattack Groups in Acute Stroke Patients - Multi-Center Trials (급성기 중풍환자의 재발군과 초발군에 대한 단면조사연구 - 다기관 임상연구)

  • Lee, In-Whan;Gwak, Ja-Young;Cho, Seung-Yeon;Shin, Ae-Sook;Kim, Na-Hee;Kim, Hye-Mi;Na, Byung-Jo;Park, Seong-Uk;Jung, Woo-Sang;Moon, Sang-Kwan;Park, Jung-Mi;Ko, Chang-Nam;Cho, Ki-Ho;Kim, Young-Suk;Bae, Hyung-Sup
    • The Journal of Internal Korean Medicine
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    • v.30 no.4
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    • pp.696-707
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    • 2009
  • Objective : We designed this study to investigate differences between stroke reattack and stroke first attack group to establish fundamental data and prevent a secondary stroke. Methods : 826 subjects were recruited from the patients admitted to the department of internal medicine at Kyung Hee University Oriental Medical Center, Kyung Hee University East-West Neo Medical Center, Kyungwon University Incheon Oriental Medical Center, Kyungwon University Songpa Oriental Medical Center and Dongguk University Ilsan Oriental Medical Center from 1 April 2007 to 31 August 2009. We compared general characteristics, classification of diagnosis, subtypes of cerebral infarction, risk factors, Sasang constitution, diagnostic classifications between stroke reattck and stroke first attack groups. Results : 1. In general characteristics, age differed significantly between the reattck and first attack groups. 2. Classification of diagnosis differed significantly between reattck and first attack groups. 3. In risk factors, hypertension, diabetes mellitus, alcohol drinking, and stress were significantly different between reattck and first attack groups. 4. Diagnostic classifications were significantly different between reattck and first attack groups. Conclusion : To prevent recurrence of stroke, education on stroke risk factors associated with recurrence is needed. In addition, those who are diagnosed as Dampness-Phlegm need to be well-controlled.

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Effect of Terazosin on Posttraumatic Nightmares : A Pilot Study (외상 후 스트레스장애 환자의 악몽치료에서 Terazosin의 효과 : 예비 연구)

  • Chung, Moon-Yong;Jung, Ji-Young;Lee, Tae-Young;Kang, Suk-Hoon;Kim, Tae-Yong;Choi, Jin-Hee;Chung, Ha- Kyoung
    • Anxiety and mood
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    • v.2 no.1
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    • pp.39-44
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    • 2006
  • Objective : Chronic posttraumatic stress disorder (PTSD) is defined by the coexistence of symptoms (reexperiencing, avoidance and hyperarousal), persisting for more than months or years that causes significant impairment in social occupational functioning. This study was conducted to evaluate the effects of terazosin on posttraumatic nightmares which is one of chronic PTSD symptoms. Methods : Twenty patients with chronic PTSD and severe trauma-related nightmares were treated with terazosin (3-7 mg/day) for 8 weeks. Recurrent distressing dreams item of the Clinician administered PTSD Scale (CAPS), Total CAPS score, Clinical Global Impressions-Severity Scale (CGI-S) and Clinical Global Impressions-Change Scale (CGI-C) were performed at baseline, 4-week and 8-week. Mississippi Scale for Combat-Related PTSD and Combat Exposure Scale (CES) were used to evaluate PTSD symptom pattern and degree of exposure. Results : Significant decrease in recurrent distressing dreams item, reexperiencing, avoidance and hyperarousal symptom score and total CAPS score were at 4-week and 8-week treatment compared to baseline (recurrent distressing dreams item : $2.70{\pm}1.88$ and $1.25{\pm}1.49$ ; reexperiencing, avoidance and hyperarousal symptom score : $2.30{\pm}2.49$, $1.20{\pm}1.05$, $3.10{\pm}1.68$ and $4.00{\pm}3.59$, $1.55{\pm}1.50$, $5.60{\pm}3.23$ ; total CAPS score : $8.20{\pm}6.26$ and $5.40{\pm}5.89$). There were significant correlation between dosage of terazosin and improvement of PTSD symptoms. Adverse effects such as fatigue and orthostatic hypotension were showed, which were mild and self-limited. Conclusion : These results suggest that terazosin may improve severe trauma-related nightmares and overall PTSD symptoms. Randomized controlled study with more subjects would be necessary in the future.

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The Effect of Carrot Juice, ${\beta}$-carotene Supplementation on Plasma Antioxidant Status of Korean Smokers (당근즙 및 ${\beta}$-Carotene의 섭취가 흡연자의 혈장 항산화 영양 상태에 미치는 영향)

  • Lee, Hye-Jin;Park, Yoo-Kyoung;Kang, Myung-Hee
    • Journal of Nutrition and Health
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    • v.42 no.8
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    • pp.750-758
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    • 2009
  • Smoking is associated with an increased incidence of numerous cancers and other degenerative diseases. It has been suggested that high consumption of fruits and vegetables may give some protection. Especially carrot is the most important source of dietary ${\beta}$-carotene. Therefore, the objective of this study is to investigate whether carrot juice supplementation to smokers have different or superior effect of compared to the effect supplementing purified ${\beta}$-carotene. The study was conducted in a randomized and placebo-controlled design, after a depletion period of 14 days, 48 smokers were supplemented either carrot juice (n = 18), purified ${\beta}$-carotene (n = 16) or placebo (n = 14). Each group was supplemented for 8 weeks with approximately 20.49 mg of ${\beta}$-carotene/day and 1.2 mg of vitamin C/day, as carrot juice (300 mL/day) or purified ${\beta}$-carotene (1 capsule/day). Plasma vitamin C, vitamin E and ${\beta}$-carotene level were significantly increased after carrot juice and ${\beta}$-carotene supplementation. These results suggest that carrot juice containing ${\beta}$-carotene or ${\beta}$-carotene itself have similar antioxidative potentials by increasing the antioxidant potential in smokers. Therefore, we suggest moderate dose of vitamin supplementation (amount of two servings of vegetable intake) may help to replenish the decreased oxidative stress levels in smokers.

Crystal Structure and Physical Property of Tetragonal-like Epitaxial Bismuth Ferrites Film

  • Nam, Joong-Hee;Biegalski, Michael;Christen, Hans M.;Kim, Byung-Ik
    • Proceedings of the Korean Magnestics Society Conference
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    • 2011.06a
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    • pp.7-8
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    • 2011
  • Basically, the lattice mismatch between film and substrate can make those BiFeO3(BFO) films distorted with strain structure. BFO phase can be stabilized on LaAlO3(LAO) represents the example of a multiferroic with giant axial ratio. Its crystal structure is not strictly tetragonal, but tetragonal with a slight monoclinic distortion and related to the rotation of the oxygen octahedra. In this study, we show that phases with a tetragonal-like epitaxial BFO films can indeed be ferroelectric and also can be stabilized via epitaxial growth onto LAO. Recent reports on epitaxial BFO films show that the crystal structure changes from nearly rhombohedral ("R-like") to nearly tetragonal("T-like") at strains exceeding approximately -4.5%, with the "T-like" structure being characterized by a highly enhanced c/a ratio. While both the "R-like" and the "T-like" phases are monoclinic, our detailed x-ray diffraction results reveal asymmetry change from MA and MC type, respectively. By applying additional strain or by modifying the unit cell volume of the film by substituting Ba for Bi, the monoclinic distortion in the "T-like" MC phase is reduced, i.e. the system approaches a true tetragonal symmetry. There are two different M-H loops for $Bi_{1-x}Ba_xFeO_{3-{\delta}}$(BBFO) and BFO films on SrTiO3(STO) & LAO substrates. Along with the ferroelectric characterization, these magnetic data indicate that the BFO phase stabilized on LAO represents the first example of a multiferroic with giant axial ratio. However, there is a significant difference between this phase and other predicted ferroelectrics with a giant axial ratio: its crystal structure is not strictly tetragonal, but tetragonal with a slight monoclinic distortion. Therefore, in going from bulk to highly-strained films, a phase sequence of rhombohedral(R)-to-monoclinic ["R-like" MA-to-monoclinic, "T-like" MC-to-tetragonal (T)] is observed. This sequence is otherwise seen only near morphotropic phase boundaries in lead-based solid-solution perovskites (i.e. near a compositionally induced phase instability), where it can be controlled by electric field, temperature, or composition. Our results show that this evolution can occur in a lead-free, stoichiometric material and can be induced by stress alone. Those major results are summarized as follows ; 1) Ba-doping increases the unit cell volume, 2) BBFO on LAO can be fully strained up to x=0.08 as a strain limit (Fig. 1), 3) P(E) & M(H) properties can be tuned by the variation of composition, strain, and film thickness.

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Effects of Antioxidant Nutrient Supplementation on the Lipid Peroxidation and Antioxidative Enzyme Activities in Patients with Coronary Heart Disease

  • Joung, Hyojee;Chun, Byung Yeol;Choi, Young Sun;Kim, Sueun;Park, Wee Hyun;Jun, Jae Eun;Chae, Shung Chull;Song, Kyung Eun;Cho, Sung Hee;Oh, Hee Sook
    • Preventive Nutrition and Food Science
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    • v.6 no.1
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    • pp.51-56
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    • 2001
  • This study was carried out to evaluate whether antioxidant nutrient suppplementation with $\alpha$-tocopherol, vitamin C, $\beta$-carotene, and selenium reduces the lipid peroxide levels and increases the antioxidative enzyme activities in patients with coronary hart disease. Eighty nine patients participated in a randomized, double-blind, placebo-controlled trial. The antioxidant group (45 patients) was given daily doses of $\alpha$-tocopherol (400 IU), vitamin C (50 mg), $\beta$-carotene (15 mg), and selenium (50 $\mu\textrm{g}$) and forty four patients received a placebo. Thirty eight subjects (84.4%) of the antioxidant group and thirty nine subjects (88.6%) of the placebo group completed the three-month supplementation. Serum levels of tocopherol, vitamin C and $\beta$-carotene significantly increased in the antioxidant group compared with the baseline (p<0.05). Thiobarbituric acid-reactive substances(TBARS) decreased significantly (0.6 nmol MDA/mL) in the antioxidant group compared with that (0.09 nmol MDA/mL) in the placebo group (p=0.03). However, antioxidant supplementation did not affect the level of oxidized-LDL measured as autoantibodies against oxidized-LDL. The superoxide dimutase activity in red blood cells increased in the antioxidant group compared with the baseline (p<0.05). However, glutathione peroxidase activities did not change after supplementation in both groups, and catalase activity significantly decreased in the placebo group (p<0.05). These results suggest that antioxidant supplementation for 3 months with $\alpha$-tocopherol, vitamin C, $\beta$-carotene and selenium in patients with coronary heat disease may be partially protective against oxidative stress.

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Hypertonicity Down-regulates the $1{\alpha},25(OH)_2$ Vitamin $D_3$-induced Osteoclastogenesis Via the Modulation of RANKL Expression in Osteoblast

  • Jeong, Hyun-Joo;Yushun, Tian;Kim, Bo-Hye;Nam, Mi-Young;Lee, Hyun-A;Yoo, Yun-Jung;Seo, Jeong-Taeg;Shin, Dong-Min;Ohk, Seung-Ho;Lee, Syng-Ill
    • International Journal of Oral Biology
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    • v.30 no.1
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    • pp.23-30
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    • 2005
  • Bone remodeling is a process controlled by the action of two major bone cells; the bone forming osteoblast and the bone resorbing osteoclast. In the process of osteoclastogenesis, stromal cells and osteoblast produce RANKL, OPG, and M-CSF, which in turn regulate the osteoclastogenesis. During the bone resorption by activated osteoclasts, extracellular $Ca^{2+}/{PO_4}^{2-}$ concentration and degraded organic materials goes up, providing the hypertonic microenvironment. In this study, we tested the effects of hypertonicity due to the degraded organic materials on osteoclastogenesis in co-culture system. It was examined the cellular response of osteoblastic cell in terms of osteoclastogenesis by applying the sucrose, and mannitol, as a substitute of degraded organic materials to co-culture system. Apart from the sucrose, mannitol, and NaCl was tested to be compared to the effect of organic osmotic particles. The addition of sucrose and mannitol (25, 50, 100, 150, or 200 mM) to co-culture medium inhibited the number of tartrate-resistant acid phosphatase (TRAP) positive multinucleated cells induced by 10 nM $1{\alpha},25(OH)_2vitaminD_3$ ($1{\alpha},25(OH)_2D_3$). However, NaCl did exert harmful effect upon the cells in this co-culture system, which is attributed to DNA damage in high concentration of NaCl. To further investigate the mechanism by which hypertonicity inhibits $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis, the mRNA expressions of receptor activator of nuclear factor (NF)-kB ligand (RANKL) and osteoprotegerin (OPG) were monitored by RT-PCR. In the presence of sucrose (50 mM), RANKL mRNA expression was decreased in a dose-dependent manner, while the change in OPG and M-CSF mRNA were not occurred in significantly. The RANKL mRNA expression was inhibited for 48 hours in the presence of sucrose (50 mM), but such a decrement recovered after 72 hours. However, there were no considerable changes in the expression of OPG and M-CSF mRNA. Conclusively, these findings strongly suggest that hypertonic stress down-regulates $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis via RANKL signal pathway in osteoblastic cell, and may playa pivotal role as a regulator that modulates osteoclastogenesis.

Use of East Deep Sea Water for the Increase of Functional Components of Ginseng (Panax ginseng C.A. Meyer) and Tomato (Lycopersicon eculentum L.) (인삼과 토마토의 기능성 성분 증진을 위한 동해 해양심층수의 이용)

  • Woo Cheon-Seok;Kang Won-Hee
    • Korean Journal of Plant Resources
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    • v.19 no.2
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    • pp.331-335
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    • 2006
  • This experiment was conducted to investigate the effect of deep sea water on fruit quality and yield of tomato. In the deep sea water treatments, fruit growth and weight were decreased as the concentration of deep sea water increased. Especially, the fresh weight of second truss was decreased significantly than first truss. Soluble solid content was increased significantly in higher concentration treatment especially at 30mM and 40mM treatment. That was increased more in the first than in the second truss fruits. Most of hexose in fruits were glucose and fructose. The reason of increased glucose and fructose contents was the decline of growth because of salinity stress by deep sea water treatment. however deep sea water treatment increased the lycopene content, especially in 20mM treatment. It is assumed that deep sea water treatment cause induction and promotion of ethylene. The higher concentration of deep sea water to the solution, the eater fruit quality improvement was noticed. However, proportional yield reduction accompanied concentration, 20mM deep sea water improved fruit quality without a significant yield reduction. The Re content was the highest among ginsenosides in all treatments. The contents total of ginsenosides in all treatments, except EC 8 treatment, was higher than those in the controlled treatment. The PT/PD value was 1.31 of the lowest in the EC 8 treatment and was 2.52 of the highest in the EC6 treatment. Rf contents in high increase was detected at all treated ginseng roots.

Study on tension-tension fatigue strength properties of underwater welded joints of SM41A-2 Plate-to-Plate (수중용접한 국산 SM41A-2강판의 편진반복 인장하중하의 피로강도특성에 관한 연구)

  • 오세규;박주성;한상덕
    • Journal of Advanced Marine Engineering and Technology
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    • v.11 no.2
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    • pp.71-81
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    • 1987
  • Nowadays, the high development of industrial technique demands the optimal design of marine structures to be welded under the water, because the underwater welding of the ship hull and marine structures can decrease manpower and cost of production. However there is not available at present any report on fatigue behavior about underwater welded joints. In this paper under tention- tension repeated fatigue stress with frequency of 10 cycles per second by local controlled system, the fatigue strength properties of underwater welded joints of SM41A-2 Plate-to-Plate of 10 mm thickness were experimentally examined. The results obtained were as follows : 1) The fatigue strength of underwater welded joints of SM41A-2 was peaked at the heat input of about 1, 400 joule/mm(180 A, 36 V), while, at the heat input of more than about 1, 100 joule/mm (160 A, 33 V) that of the underwater welds at the higher than cycle of life rather than the lower cycle was higher than that of the base metal but lower than that of the atmosphere welds on account of both cooling and notch effects. 2) The fatigue limit of underwater welds increased with an increase of heat input resulting in a peak of that at the heat input of about 1, 400 joule/mm and then decreased gradually. 3) The fatigue strength at N cycles was peaked between the heat input of about 1, 400 and 1, 700 joule/mm where the strain was rapidly increased. 4) It was confirmed that the optimal zone of heat input condition for obtaining the underwater welds fatigue strength higher than that of the base metal exists, and if out of this zone, the fatigue strength of the underwater welds was lower than that of the base metal because of lack weld penetration, inclusion of slag, voids, etc. 5) By the fatigue test, the underwater welds fractured brittly without visual deformation, so the strain was remarkably less than of the atmosphere welds. 6) The fatigue life factor was peaked at the heat input of about 1, 600 joule/mm (200 A, 36 V) at which the mean strain is a little higher than that of the base metal but quite lower than those of the atmosphere welds, resulting in good underwater welds because both fatigue strength and ductility of the underwater welds are higher than those of the base metal at such heat input.

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