• Title/Summary/Keyword: water control

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A study on the Effectivness of Hand-made Paraffin Thyroid Phantom (Paraffin을 이용한 Thyroid Phantom제작에 따른 유용성에 관한 연구)

  • Park, Soung-Ock;Lee, In-Ja
    • Journal of radiological science and technology
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    • v.30 no.3
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    • pp.237-243
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    • 2007
  • Phantoms are very necessary for quality assurance of radio nuclides imaging systems to maintain standards and to ensure reproducibility of test. General quality assurance and instrument quality control are essential in every hospital. The human tissue equivalent materials are aluminum, areryl, water and epoxy..etc. It is very important to select optimum equivalant materials for a phantoms in QC. Especially, paraffin is very similar with human soft tissue in X or Gamma-ray physical characteristics and easy to buy with economically. We made a paraffin thyroid phantom and compare with thyroid areryl phantom, also used commercially in practice. Two small size cold spots(3 and 6 mm diameter) and a hot spot(3 mm diameter) embeded in paraffin phantom. And imaged with $^{99m}TcO_4$ by camera for analysis about spatial resolution and noise at the hot and cold spots. We got some results as below : 1. No difference in counting rate and noise between both arcryl and paraffin thyroid phantoms. 2. The best spatial resolution can be seen 6 cm distance between pinhole collimator and thyroid phantoms(arcryl and paraffin). 3. More optimal spatial resolution could acquired in paraffin thyroid phantom. Paraffin is very similar with human soft tissue in atomic number, density and relative absorbtion function, and can be shaped easily what we wanted. So we can recommendation paraffin as quality assurance phantom because its usefulness, economical benefit and purchasability.

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Phytoremediation of diesel-contaminated soils using alfalfa (Alfalfa를 이용한 디젤오염토양의 phytoremediation)

  • 심지현;이준규;심상규;황경엽;장윤영
    • Journal of Korea Soil Environment Society
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    • v.4 no.2
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    • pp.127-136
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    • 1999
  • In the past several years phytoremediation, defined as the use of plants for removing contaminants from media such as soils or water, has attracted a great deal of interest as a potentially useful remediation technology We attempted to assess the effectiveness of phytoremediation of diesel-contaminated soils in a green house. Screening test for selecting an appropriate plant was performed by observing the harmful effects of diesel dosage on the growth of 4 plants. Alfalfa was selected as a potentially useful plant among corn and barnyard grasses due to its high tolerance to the toxicity of diesel in growth. Bioremediation of the artificial diesel-contaminated soil packed in the PVC columns(0.3m in diameter $\times$ 1m in length) with air supplied, alfalfa planted, and alfalfa and air supplied was investigated for 100 days. The results of the column test showed plant effects on enhancing the biodegradation of diesel in the contaminated soils compared to the control column which had no plant. Injecting air to the columns during phytoremediation also showed additional effects on the removal rate of diesel. Comparison of microbial activity in each test column showed a beneficial effect of plants in the soil remediation processes. This results can be explained microbial activity in rhizosphere is a crucial factor for removing diesel.

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Acute Toxicity of Kami-Okchun-San in ICR-Mice (가미옥천산의 ICR 마우스 경구 투여에 의한 급성 독성시험 연구)

  • Ko Byoung-Seob;Park Min-Jung;Park So-Min;Jeon Won-Kyung;Chun Jin-Mi;Joung Pil-Mun;Park Sun-Min;Choi Soo-Bong;Oh Myung-Sook;Chang Mun-Seog;Park Seong-Kyu
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.5
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    • pp.1200-1203
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    • 2005
  • Kami-Okchun-San(OCS) is known as an effective herbal medicine on Type 2 diabetes. We peformed to investigate acute toxicity of OCS on ICR mice. ICR mice in acute toxicity experiment were administered orally with dosages of 3,200mg/kg (low dosage group), 4,000mg/kg (middle dosage group), 5,000mg/kg (high dosage group) per single time, respectively. Body weights, clinical signs, motalities and histopathological finding were observed daily for 14 days according to the Regulation of Korean Food and Drug Administration(1999. 12. 22). Single oral administration of OCS with different dosages, no animals died of the test drug. Autopsy of animal revealed no abnormal gross findings. Therefore, LD50 value of OCS for ICR mice was more than 5,000mg/kg on oral route. Normally increasing changes were observed in body weight, drinking water and food intake in every dosage group. Hematological parameters were also observed normally in all animals. No histopathological lesions were observed in both control and treated animals. Above data suggest that no toxic dose level of OCS in ICR mice is considered to be more than 5,000mg/kg. Therefore, it was concluded that OCS have no effect on acute toxicity and side effect in ICR mice.

The Recovery Effects of Joojakwhan - A Traditional Korean Medical Poly-herbal Drug for the Cognitions and Motor Functions in Mild Stroke Rat Model by Using Transient Middle Cerebral Artery Occlusion (주작환(朱雀丸)이 일시적 국소 뇌허혈 유발 백서(白鼠)에 대한 인지 및 운동기능 회복에 미치는 효과)

  • Kim, Bo-Eun;Kang, Seok-Bong;Chung, Dae-Kyoo
    • Journal of Oriental Neuropsychiatry
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    • v.24 no.4
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    • pp.419-434
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    • 2013
  • Objectives: The object of this study is to observe the cognition and motor function recovery effects of Joojakwhan (JJW), a traditional Korean poly-herbal formula for treating various neuropsychiatric diseases such as dementia, for the mildly stroke rats, with 60 minutes of reperfusion transient middle cerebral artery occlusion (tMCAO). Methods: In the present study, 125, 250 and 500 mg/kg of JJW were orally administered, once per day for 10 continuous days 2 hours after the tMCAO. The body weight changes, infarct sizes under 2% 2, 3, 5-triphenyl tetrazolium chloride (TTC) stain, sensorimotor functions and cognitive motor behavior tests were serially monitored with cerebral caspase-3 and cleaved poly (ADP-ribose) polymerase (PARP)-immunoreactivities and histopathological changes. The effects of tMCAO on sensorimotor functions were evaluated by using of limb placing and body-swing tests, and the cognitive motor behaviors were also observed with water maze tests. Results: From the results of tMCAO, with marked decreases of body weights, disorders of sensorimotor functions increases the limb placing test scores, and decrease the numbers and percentages of body swings to the ipsilateral sides. The cognitive motor behaviors increases the distances and time to reach the escape platform which included the inhibitions of the decreases with repeated trials that were observed with focal cerebral cortex infarct volumes. In addition, the marked increases of the atrophy, numbers of degeneration, caspase-3- and PARP-immunoreactive cells around peri-infarct ipsilateral cerebral cortex were also observed in tMCAO controls when compared with the sham control rats, respectively. Conclusions: The results obtained from this study suggest that oral administrations of JJW indicate obvious cognitions and motor function recoveries of the rats with tMCAO, mild strokes, which are mediated by neuro-protective effects through known antioxidant effects of components.

EXperimental Studies on the Hair Growth Activity of Mylabris Phalerata Pall. Extracts and Fractions in C57BL/6N Mice (C57BL/6N 생쥐에서 반모추출물과 분획물을 이용한 발모(發毛)효과에 대한 실험적 연구)

  • Jo, Han-Young;Kim, Tae-Heon;Kim, Ho;Jeong, Han-Sol;Lee, Chang-Hyun;Lee, Gwang-Gyu
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.2
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    • pp.357-364
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    • 2008
  • Mylabris is the dried body of the chinese blister beetle. The species used in medicine are Mylabris phalerata and M. cichorii. In recent studies, it has been found that Mylabris possesses antitumor properties, increases the number of leukocytes, and has irritant effects on the urinary organs. The crude extracts of Mylabris have been noted for their highly irritant action and other traditional uses of Mylabris include treatment of poor local blood circulation. The active constituent of Mylabris is cantharidin. The chemical is notable for its vesicant properties, but with severe side effects such as nephrotoxicity. This experiment examined the effect of extracts and fractions, obtained from Mylabris phalerata Pall. on hair growth activity of the C57BL/6N mice after topical application to skin. First, we examined the effect of an extracts, obtained from the alcohol extracts of dried Mylabris phalerata Pall. on hair growth activity of the C57BL/6N mice after topical application to skin. Second, we examined on hair growth activity of the cantharidin fraction of Mylabris phalerata Pall. compared to the control and 1% minoxidil groups. Third, we investigated the number of hair follicle and mast cells after topical application of extracts of Mylabris phalerata Pall. to skin for 16 days. The results were as follows: Hair growth effect from the extracts of Mylabris phalerata Pall.(0.312%) was observed in 80% of mice whose hair had been removed in 13 days. Hair growth effect from the extract of Mylabris phalerata Pall.(0.312 and 0.625%) and 1% minoxidil group was observed in 100% of mice whose hair had been clipped in 20 days. Hair growth effect from the cantharidin fraction(0.5%) and water fraction(0.5%) of Mylabris phalerata Pall. was observed in 100% of mice whose hair had been clipped in 24 days. The hair growth effect on the cantharidin fraction(0.125%) was observed to be strong compared with the minoxidil(3%) group, commercial hair growth agents, in mice whose hair had been clipped in 19 days. In the spontaneous alopecia mice model, the hair growth effect from the cantharidin fraction (0.125%) was observed to be strong as compared with the states before the 13 days experiment. These experiments suggest that extracts and fractions of Mylabris phalerata Pall. may stimulate the topical hair growth activity in low doses.

Hepatoprotective effects of the aqueous extract from Taraxacum officinale (Dandelion) against Thioacetamide-induced hepatotoxicity in rats (Thioacetamide로 유발된 간 손상에 대한 Taraxacum officinale (Dandelion) 추출물의 효과)

  • Cho, In-Young;Ma, Se-Ryung;Moon, Sun-Jin;Yu, Do-Hyeon;Shin, Sung-Shik;Son, Chang-Ho;Oh, Ki-Seok;Hur, Tai-Young;Jung, Young-Hun;Choi, Chang-Yong;Suh, Guk-Hyun
    • Korean Journal of Veterinary Service
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    • v.36 no.4
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    • pp.233-242
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    • 2013
  • The genus Taraxacum, known by the common name Dandelion, is a medicinal herb in the family Asteraceae. It has been traditionally used as a folk medicine for the treatment or prevention of various diseases due to its anti-inflammatory and anti-oxidative properties. In this study, we attempted to evaluate protective effects of Dandelion related with anti-oxidative activity to Thioacetamide (TAA)-induced liver damage. 36 rats were randomly assigned to six experimental groups : Control, Dandelion water extract (DWE), TAA, TAA&DWE 300, TAA&DWE 600, TAA&DWE 1,200 groups. Rats in DWE and TAA&DWE groups were pretreated with DWE (300, 600 or 1,200 mg/kg BW) by gavage for 7 days. All rats were treated intraperitoneally with TAA (200 mg/kg BW) or normal saline at 12 hours after last oral administration and sacrificed at 12 hours after last treatment. Levels of WBC and Neutrophil count were significantly decresed in TAA&DWE 1,200 group compared with that in TAA group (P<0.05). In TAA&DWE 600 and TAA&DWE 1,200 groups, serum AST, ALT, GGT levels were lower than TAA group (P<0.05). The serum TG level was significantly elevated in TAA&DWE groups compared with those in TAA group. Liver tissues from TAA group showed extensive histopathological changes, characterized by moderate or severe hepatocytes degeneration, inflammatory cell infiltration, and congestion. In the TAA&DWE group, The severity of histopathological lesions were decreased compared to those in the TAA group. The MDA concentration was significantly decreased and GSH content was significantly increased in the TAA&DWE 1,200 group compared to those in the TAA group. GR, CAT and GST activities in the TAA&DWE 1,200 group were significantly increased compared to those in the TAA group.

Effects of All-trans retinoic acid on the cholangiocarcinogenesis in Hamsters infected with Clonorchis sinensis (All-trans retinoic acid 투여가 간흡충 감염 햄스터의 담관암 발생에 미치는 영향)

  • Kim, Hak-yeop;Seo, Il-bok
    • Korean Journal of Veterinary Research
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    • v.36 no.1
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    • pp.151-159
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    • 1996
  • This study was carried out to evaluate the effects of all-trans retinoic acid(RA) on the development of cholangiocarcinoma in hamsters. Eighty six female Syrian golden hamsters were divided into four groups. Group I was for the induction of the cholangiocarcinoma, which was infected orally with C sinensis and given dimethylnitrosamine(DMN, 15ppm) in drinking water for 4 weeks. Group II was for evaluating the effect of all-trans RA treatment on the cholangiocarcinogenesis, which was treated the same as group I and orally given RA(1mg/kg, 5 times per week) for 15 weeks. Group III was given only RA hr 15 weeks. Control group IV was given only soybean oil which was solvent for RA treatment. More than 5 heads of hamsters in each group were sacrificed at 4, 7, 11 and 15 weeks after the begining of the experiment. The livers were examined grossly, histopathologically, and immunohistochemically. The results obtained were as follows : 1. Death of animals started from the 11 weeks after the begining of the experiment. One of the total 22 animals(5%) and 7 of the total 24 animals(29%) died in group I and group II, respectively. 2. Proliferation of oval cell was peaked at 11 weeks in group I and at 7 weeks in group II, and decreased gradually after those periods of the time. 3. Cholangiocarcinomas were found in 1 of 6 animals(17%) at 11 weeks and in 4 of 6 animals(67%) at 15 weeks in group I, respectively. But in group II, the cholangiocarcinomas occured in 1 of 5 animals(20%) at 7 weeks, in 7 of 12 animals(58%) at 11 weeks and in 2 of the rest animals(100%) at 15 weeks, respectively. 4. Expression of $\alpha$-fetoprotein(AFP) of the oval cells in the group II showed the same degree of positive reaction at that of group I at 4 weeks. But AFP postive oval cells decreased gradually and AFP negative oval cells(ductlike oval cells) increased gradually. 5. Expression of cytokeratin of the oval cells in group II was shown slightly at 4 weeks and the degree of expression increased moderately from the 7 weeks. But the expression of the oval cells in group I was shown slightly after the 7 weeks. These results suggested that all-trans RA promoted the occurrence and the rate of cholangiocarcinoma by inducing differentiation of small cells and oval cells in the liver of hamsters infected with C sinensis and treated with DMN.

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A Comparative Study on the Mechanical Properties of Plywood treated with Several Fire-Retardant Chemicals(II) - Effect of Platen Temperature in Press Drying on the Static Bending Strength of Treated Plywood - (수종(樹種) 내화약제(耐火藥劑)로 처리(處理)된 합판(處理)의 기술적(技術的) 성질(性質)에 관(關)한 비교연구(比較硏究)(II) - 열판건조시(熱板乾燥時) 열판온도(熱板溫度)가 처리합판(處理合板)의 휨강도(强度)에 미치는 영향(影響) -)

  • Chung, Woo-Yang;Kim, Jong-Man;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.12 no.4
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    • pp.12-18
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    • 1984
  • Soaking treated in 20% aqueous solutions of $(NH_4)_2SO_4$, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$, $Na_2B_4O_7-H_3BO_3$(60:40) and Minalith, the mixed salts for 9 hrs. the wet 3.5mm meranti (Parashorea spp.) plywoods were press-dried at 90, 120 and $150^{\circ}C$ and put to static bending test to examine the influence of redrying temperature on the strength of fire-retardant treated plywoods ill flexure. While water-soaking treatment (control) showed serious reduction in Stress at proportional limit, MOE, MOR, Work per unit volume at $150^{\circ}C$, all the fire-retardant treatments maintained bending strength even at $150^{\circ}C$ and showed rather increased values in case of some chemicals. In view of drying rate and maintenance of strength, the most pertinent platen temperature was $150^{\circ}C$ and Borax-Boric acid was the predominant fire-retardant in this study.

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Analysis of soil moisture response due to Eco-hydrological change (생태수문 변화에 따른 토양수분의 영향 분석)

  • Hur, Yoo-Mi;Choi, Min-Ha;Kim, Hyun-Woo;Kim, Sang-Dan;Ahn, Jae-Hyeon
    • Journal of Wetlands Research
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    • v.13 no.2
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    • pp.171-179
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    • 2011
  • The main objective of this study is to estimate of the vegetation response induced by climate change to soil moisture. We investigated a relationship between vegetation activity and climate variables using Moderate Resolution Imaging Spectroradiometer (MODIS)-retrieved Normalized Difference Vegetation Index (NDVI) and soil moisture. NDVI which extracted from MODIS 13 Vegetation Indices Product was considered as an useful parameter to figure out a relationship with two types of soil moisture, which were observed at Rural Development Administration sites and estimated from Advanced Microwave Scanning Radiometer E (AMSR-E) satellite imagery. The correlation of MODIS-NDVI and ground measured soil moisture were observed, became much stronger when compared to soil moisture values with time lag (5days, 10days, 15days). The correlation patterns between NDVI and soil moisture with different time lag were related to soil texture. The results from this study will be useful to understand the role of vegetation in water balance control in various scales from regional to global climate change.

Comparison of the Floodplain Vegetation Structure According to Existence of Lateral Connectivity in Streams (하천의 횡적 연결성 유무에 따른 홍수터 식생 구조의 비교)

  • Chu, Yunsoo;Jin, Seung-Nam;Cho, Hyunsuk;Cho, Kang-Hyun
    • Journal of Wetlands Research
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    • v.19 no.3
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    • pp.327-334
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    • 2017
  • The flood pulse in streams enhances the biodiversity and ecosystem services of the channel-floodplain ecosystems by exchanging water, nutrients, sediments and organisms. However, the lateral connectivity in most streams of Korea has been disrupted by the levee constructions for the purpose of flood control and land use of floodplains. To compare the characteristics of floodplain vegetation according to existence of lateral connectivity in streams, we investigated the geomorphological and soil environmental factors and structures and distribution of vegetation in the floodplains connected and isolated by levee to the channel in Cheongmi Stream, Seom River, Hwangguji Stream, Mangyeong River, Gomakwon Stream, and Boseong River, Korea. In comparison of soil environments, moisture and clay contents were higher in the isolated floodplain than in the connected floodplain. According to the result of principal component analysis (PCA) using environmental data, the environments of the connected floodplain and the isolated floodplain were separated by soil moisture contents, soil texture and distribution altitude of the vegetation. The results of detrended correspondence analysis (DCA) using vegetation data showed that the isolated floodplain was dominated by the hydropythic communities of diverse life form and that the connected floodplain was dominated by the hygrophytic communities that endure disturbance. In conclusion, it is thought that the vegetation of the floodplain changed to the lentic wetland vegetation dominated by diverse hydrophytes as the floodplain was isolated from the channel by artificial levees.