• Environmental Analysis Health and Toxicology
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• 제24권4호
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• pp.351-357
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• 2009

To investigate the alleviative effects of jujube water extract (JWE) on the inflammation and skin barrier damage, both the irradiation of UVB and the application of squalene monohydroperoxide (Sq-OOH) were applied to the back skin of experimental animals for 4 weeks. And at the same time experimental materials were applied topically. Six weeks female SKH-1 hairless mice were divided into five groups (five animals for each group) including normal (N; saline), control (C; UVB+Sq-OOH+saline), vehicle control (VC; UVB+Sq-OOH+vehicle), positive control (PC; UVB+Sq-OOH+0.01% retinoic acid) and experimental (E; UVB+Sq-OOH+JWE) groups. The skin erythema index in the E group was significantly low compared to the C group (p<0.05). Lipid (p<0.05) and water (p<0.01) capacities in the E group were significantly high compared to the C group. In comparison with the C group, E group showed a relatively well preserved lipid lamellae in the epidermis and a relatively much less infiltration of mast cells in the dermis or hypodermis. As for the both absolute and relative weights of the spleen, PC group were significantly higher than the other groups. These results suggest that JWE have a considerably inhibitory effect on the inflammation and the skin barrier damage induced by UVB irradiation and Sq-OOH application.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.110-113
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• 2002

Statistical- based, principal component analysis (PCA) was applied to chemical data from two underground storage systems containing LPG to assess the usefulness of such technique at the initial stage (Pyeongtaek) or middle stage (Ulsan) of hydrochemical studies. For the first case, both natural and anthropogenic contamination characterize regional groundwater. Saline water buffered by Namyang lake affects as a natural factor, whereas cement grouting influence as an artificial factor. For the second study area, contaminations due to operation of LPG caverns, such as disinfection activity and cement grouting effect, deteriorate groundwater quality. This study indicates that principal component analysis would be particularly useful for summarizing large data set for the purpose of subsurface characterization, assessing their vulnerability to contamination and protecting recharge zones.

• 한국수산과학회지
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• 제29권6호
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• pp.862-875
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• 1996

The CTD data observed in the sea northwest of Cheju Island have been analyzed to figure out the seasonal circulation around Cheju Island. Warm and saline waters flow into the Yellow Sea through the middle region of the Yellow Sea in winter and along the west coast of Korean Peninsula in summer. On the other hand, cold and less saline waters flow out of the Yellow Sea through the middle region in summer and along the west coast of Korean Peninsula in winter. These flows make the seasonal circulation around Cheju Island. As dynamics, the monsoon wind and the variation of Kuroshio transport have been suggested. Comparing the observational result, the circulation driven by the variation of Kuroshio transport is strengthened by monsoon winds in the numerical model.

• The Korean Journal of Physiology
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• 제11권2호
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• pp.17-22
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• 1977

By the intravenous infusion of saline solution through the postcaval vein, the effects of increasing the venous return on the heart rate were studied in the water turtle (Amyda japonica). The following results were obtained: 1) Prior to saline infusion, when the initial heart rate was below $50{\sim}55/min$ the heart rate was increased by the infusion. When the initial rate was above this value no changes in heart rate were observed following the infusion. 2) When the heart rate was decreased by vagal stimulation, the infusion elicited a remarkable increase in the heart rate. 3) Increased heart rate caused by tile infusion was not affected by vagotomy or sympathectomy. 4) These results suggest that the increase in heart rate secondary to increased venous return is under the control of a myogenic regulatory mechanism, not a neural mechanism.

• The Korean Journal of Physiology
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• 제25권2호
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• pp.189-200
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• 1991

During the past few years it has been proposed that lithium clearance can be used as a reliable measure for the outflow of tubular fluid from the proximal tubule. This study was aimed to characterize the inflow dependent reabsorption of Na in renal tubule beyond the proximal tubule. For this purpose, lithium clearance was used as a measure for the inflow from the proximal tubule and the changes in reabsorption fraction of Na and water were determined in rabbits. Rabbits were pretreated with hypotonic saline solutions for an hour (50 mM/L NaCl, 20 ml/hr/kg). And then a hypertonic solution of 500 mM/L NaCl (20 ml/kg) was administered intraperitoneally in conjunction with a bolus of LiCl solution (2 mM/kg, i.v.) for conditioning the $C_{Li}$ and urine flow rate. To rule out the effect of $Li^+$ on tubular functions, a bolus of NaCl solution (2 mM/kg, i.v.) was administered. Fifteen, thirty, and sixty minutes after injection of hypertonic saline arterial blood and urine samples were taken. Urinary and plasma concentrations as well as urinary output of $Li^+,\;Na^+\;and\;K^+$ were measured. From these $C_{Li},\;C_{Na}$ and the reabsorption fraction of Na and water $(Fr_{Na}\;&\;FrH_2O)$ were calculated. These results were compared with those from control groups in which the same amount of isotonic saline (145 mM/L NaCl) and of 15% dextran solution were administered in the same way as that in experimental group. Followings are the results obtained. 1) The plasma concentration of $Na^+$ in rabbits injected with hypertonic saline reached the peak value after 15 min and thereafter no significant change was observed. Hematocrit values did not show any change, while urinary excretion of $Na^+$ increased markedly during the first 15 min and decreased thereafter. These results were not affected by an injection of a small amount of LiCl. 2) The clearances of $Li^+,\;Na^+\;and\;K^+$ in rabbits injected with hypertonic saline and LiCl solution decreased. 3) In spite of the variation in $C_{Li},\;Fr_{Na}$ did not show any significant change while $FrH_2O$ increased gradually. 4) $C_{Li}$ decreased also in rabbits received isotonic saline. $Fr_{Na}$ tended to be higher than that in hypertonic saline group, while $FrH_2O\;and\;Fr_{Na}$ did not associated with the decrease in $C_{Li}$. 5) $C_{Li}$ of the rabbits received dextran solution fluctuated persistently and $Fr_{Na}\;and\;FrH_2O$ did not change in along with $C_{Li}$ although $Fr_{Na}$ had a tendency to be higher than that in hypertonic saline group. 6) From the above results it was concluded that: (a) In rabbits with normal body store of $Na^+$, the $Fr_{Na}$ of renal tubule beyond proximal tubule. calculated from $C_{Li}$ as a measure of inflow from proximal tubule is constant in spite of variations in $C_{Li}$. (b) The $FrH_2O$ calculated from $C_{Li}$ is dependent largely upon ADH rather than inflow from proximal tubule. (c) When there is a decrease in plasma $Na^+$ concentration or ineffective body fluid. $Li^+$ reabsorption may occur in the thick segnent of Henle's loop and hence the determination of $Fr_{Na}$ and $FrH_2O$ will not be easy one, but $Fr_{Na}$ is constant under the same experimental conditions.

• 한국작물학회지
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• 제38권5호
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• pp.398-404
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• 1993

우척지에서의 수도재배는 일반 숙답과는 토양조성이 다르고, pH가 높고, C.S.C가 낮으며, 염해의 피해가 커 벼의 생육을 저해한다. 특히 벼 이질시의 손상에 의한 피해를 줄이고자 Rotary 후 환수 회수 및 이질시기가 토양의 염분농도 변화 양상과 벼의 생육 및 수량등에 미치는 영향을 조사하였다. 1. 염분농도는 염농도 0.35%의 포장에서 담수하여 Rotary한 직후에 0.41%로 높아졌고, Rotary후 환수를 3, 4회 실시할 수록 0.2%까지 낮아졌으며, 담수호액도 0.2%에서 0.11%로 낮아졌다. 2. 토층별 염분농도는 5cm 깊이 내에서 1회 환수후에는 0.31%이었으며, 3～4회 환수를 많이 할수록 낮아져 0.22%로 감소되었고, 7cm 이하에서는 염분농도의 감소 정도가 적었다. 3. 이질묘의 고사는 염농도 0.35% 포장에서는 Rotary후 익일 이앙이 37%로 높았으나, 3회 환수 6일 이앙한 처리구는 20%로 적었으며, 0.50% 포장에서는 0.35% 포장보다 고사율은 높았으나 경향치는 같았다. 4. 수량은 염농도 0.35% 포장에서는 Rotary후 3회 환수하여 6일째 이앙한 처리가 350kg/10a으로 관행(1회 환수 익일 이앙)에 비하여 14% 증수하였고, 염농도 0.50% 포장에서는 이앙묘의 손상이 심하여 관행(73kg/10a)에 비하여, 3회 환수 6일째 이앙한 것이 250kg/10a으로 매우 높았다. 고농답에서 Rotary후 2일 이내에 이앙은 제염효과가 낮아 생육이 불량하고, 고농답 일수록 2～3회 환수와 5～6일 경과후 이앙하는 것이 활착이 양호하고 고사주율이 낮아, 초기 생육이 양호하였다. 그러나 이앙시기가 8일이 지나 10日 이상으로 늦어질수록 토양의 경화로 인하여, 이앙시 부묘가 않아 결주율이 높았으며 수량도 감소되 는 경향이었다.

• 한국토양비료학회지
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• 제48권6호
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• pp.618-627
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• 2015

Soil salinity is the most critical factor for crop production at reclaimed tidal saline soil. Subsurface drainage system is recognized as a powerful tool for the process of desalinization in saline soil. The objective of this study was to investigate the effects of subsurface drainage systems on soil salinity and corn development at Saemangeum reclaimed tidal saline soil. The field experiments were carried out between 2012 and 2014 at Saemangeum reclaimed tidal land, Buan, Korea. Subsurface drainage was installed with four treatments: 1) drain spacing of 5 m, 2) drain spacing 10 m, 3) double layer with drain spacing 5 m and 10 m, and 4) the control without any treatment. The levels of water table showed shorter periods above 60 cm levels with the deeper installation of subsurface drainage system. Water soluble cations were significantly greater than exchangeable forms and soluble Na contents, especially in surface layer, were greatly reduced with the installation of subsurface drainage system. Subsurface drainage system improved biomass yield of corn and withering rate. Thus, the biomass yield of corn was improved and the shoot growth was more affected by salinity than was the root growth. The efficiency of double layer was not significant compared with the drain spacing of 5 m. The economic return to growers at reclaimed tidal saline soil was the greatest by the subsurface drainage system with 5 m drain spacing. Our results demonstrated that the installation of subsurface drainage system with drain space of 5 m spacing would be a best management practice to control soil salinity and corn development at Saemangeum reclaimed tidal saline soil.

• Journal of Microbiology and Biotechnology
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• 제17권2호
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• pp.364-368
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• 2007

Enterobacter sakazakii may be related to outbreaks of meningitis, septicemia, and necrotizing enterocolitis, mainly in neonates. To reduce the risk of E. sakazakii in baby foods, thermal characteristics for Korean E. sakazakii isolates were determined at 52, 56, and $60^{\circ}C$ in saline solution, rehydrated powdered infant formula, and dried baby food. In saline solution, their D-values were 12-16, 3-5, and 0.9-1 min for each temperature. D-values increased to 16-20, 4-5, and 2-4 min in rehydrated infant formula and 14-17, 5-6, and 2-3 min in dried baby food. The overall calculated z-value was 6-8 for saline, 8-10 for powdered infant formula, and 9-11 for dried baby food. Thermal inactivation of E. sakazakii during rehydration of powdered infant formula was investigated by viable counts. Inactivation of cultured E. sakazakii in infant formula milk did not occur for 20 min at room temperature after rehydration with the water at $50^{\circ}C$ and their counts were reduced by about 1-2 log CFU/g at $60^{\circ}C$ and 4-6 log CFU/ml with the water at 65 and $70^{\circ}C$. However, the thermo stability of adapted E. sakazakii to the powdered infant formula increased more than two times. Considering that the levels of E. sakzakii observed in powdered infant formula have generally been 1 CFU/100 g of dry formula or less, contamination with E. sakazakii can be reduced or eliminated by rehydrating water with at least $10^{\circ}C$ higher temperature than the manufacturer-recommended $50^{\circ}C$.

• 자원환경지질
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• 제24권3호
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• pp.319-327
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• 1991

제주도(濟州島)는 화산암(火山岩)과 화산쇄설오퇴적층으로 형성(形成)된 한반도(韓半島)에서 가장 큰 섬이다. 지형(地形)은 저지대(低地帶)로 현무암(玄武岩)이 넓게 분포(分布)하며 섬 중앙(中央)에는 1950m의 화산(火山)이 우뚝 솟아 있으며 정상에는 화산분출(火山噴出)에 의(依)해 형성(形成)된 화구(火口)가 존재(存在)한다. 지표수(地表水)의 유출(流出)은 대단히 빈약하여 용수이용(用水利用)은 지하수(地下水)와 용출수(湧出水)에 거의 의존(依存)한다. 본(本) 도(島)에는 약(約) 1650여개소의 지하수개발공(地下水開發孔)이 있는데 대부분 $1,000{\sim}2,000m^3/day$의 산출(産出)이 가능(可能)하다. 근래에 와서 지하수이용증대(地下水利用增大)에 따라 해안(海岸) 인접지역 특(特)히 동부지역중(東部地域中) 일부(一部)에서는 해수침입현상(海水侵入現象)이 일어나고 있다. 이 지역(地域)의 지형(地形)은 아주 평저하고 지하수위(地下水位)도 해수면(海水面)가까이에 위치(位置)하여 지하수의 과잉 양수(揚水)는 결국 해안(海岸)으로부터 최고(最高) 6km 내륙까지 해수침입(海水侵入)을 초래하게 되었다. 이러한 문제를 해결하기 위(爲)하여서는 장기(長期) 수리화학적(水理化學的)인 감시체계망 설치가 무엇보다도 필요(必要)하다.

• 한국해양학회지:바다
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• 제3권1호
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• pp.45-52
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• 1998

1996년 하계동안 한국 서해 대안반도 연근해에서 부유퇴적물의 총함량과 분포경향 및 부유물질의 입도특성을 측정하였고, 수온과 염분의 수괴특성치와 비교하여 부유퇴적물의 운반양상을 해석하였다. 연구해역의 하계 수괴 특성은 수온과 염분이 수직적으로 균질한 연안수괴와 수온약층이 뚜렷한 외양수괴로 구분되는 바, 연안수와 외양수는 강한 조석전선의 영향으로 활발하게 혼합되지 않았다. 그런데 경기만으로부터 유래된 저염의 연안수는 조석전선의 외양역에서 밀도약층대를 따라 중층 저염수를 형성하였고, 남쪽방향으로 이동하는 것으로 분석되었다. 부유물 총함량(TSM)은 경기만 입구의 연안수역에서 5 mg/l 이상으로 높았으며, 외양수역에서 대체로 2 mg/l 이하로 낮게 측정되었다. 외양수역에서는 수괴 홍탁도가 상층과 하층에 비하여 높게 나타나는 중층 혼탁수가 형성되었으며, 경기만 연안해역에서 유래한 부유물질은 위에서 설명된 수괴이동을 따라 남쪽방향으로 이동되는 것으로 규명된다. 부유물질의 입자크기는 전체적으로 2~9 ${\mu}m$의 평균입자 범위이며, 평균입자가 7 ${\mu}m$ 이상인 조립질 부유물은 경기만 연안수역의 혼탁수와 외양역 중층 저염수의 혼탁수에서 우세하다. 따라서 수괴분포와 연관된 부유물질의 입자특성은 부유물질의 이동과 거동방향의 해석에 긍정적인 자료로 여겨진다.