• Title/Summary/Keyword: dark pretreatment

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Effect of Photosynthesis on Ozone-Induced Ethylent Evolution from Tomato Plants (토마토 식물에 있어서 광합성이 유존유동성의 에틸렌 생성에 미치는 영향)

  • 배공영
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.3
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    • pp.307-314
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    • 1996
  • The rate of evolution of ethylent by tomato plants was rapidly increased by ozone fumigation. In the present study, the mechanism of ethylent evolution by ozone was investigated in experiments with aminoethoxyvinylglycine (AVG) and tiron, which inhibit the formation of ethylene and peroxidation of lipids, respectively. Pretreatment with AVG significantly inhibited the ozone-induced ethylent evolution, but the treatment of plants with tiron did not inhibit. These results indicate that the induction of the evolution of ethylene by ozone involves the pathway via aminocyclopropane-1-carboxylate (ACC), while not released as a result of the peroxidation of lipids. Ozone-induced ethylent evolution was greater in dar- than light-incubated, intact tomato plants. The difference between dark- and light-ethylene evolution was examined with diuron, an inhibitor of photosynthetic electron transport. The inhibitor treatment promoted ethylent evolution. These results suggest that ethylent retention and metabolism in plants were regulated by internal $CO_2$ levels which, in turn, were controlled in large part by photosynthesis. Thus, ethylene was retained in illuminated leaf tissue under low intenal $CO_2$ concentration which may develop in a sealed container without exogenously supplied $CO_2$.

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The Study on Scattering of Chromosomes in Cells -Scattering of Chromsomes by Treatment with Potassium Ferricyanide Solution under Light- (세포내 염색체의 분산에 관한 연구 -적혈염용액의 광조사 처리에 의한 염색체의 분산-)

  • 김종호
    • Journal of Plant Biology
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    • v.17 no.3
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    • pp.113-117
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    • 1974
  • In counting chromosome number and karyotype study, it is necessary to let chromosomes on metaphase by pretreatment before fixation. For this purpose, colchicine, or 8-oxyquinoline are generally used. The author found out that chromosomes could be scattered by illuminating cyanoferrate complex solution in which root-tips were sunk. As materials, 8 sorts of plant such as Allium fisturosum, allium tuberosum Rottler, Triticum vulgare were used. Their root-tips were sunk on the bottom of beaker in potassium ferricyanide solution $3{\times}10-4M$ and illuminated through the solution by sterilizing lamp for 1~2 hours in dark room, keeping 10 cm distance from light source to the surface of solution and 2cm depth of solution. Then again, they were illuminated to the light which was somewhat weaker intensity than the former (distance, 16cm; depth, 3cm) for 1.5~2 hours after immersed in 1/100N-HCl and washed in water for each 5minutes. By such methods chromosomes could be scattered. About the mechanism of scattering, it is supposed that CN and Fe(CN)x ions $(x {\leq}5)$ which were gradually produced in the process of photodissociation acted together on the scattering of chromosomes.

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Immunohistochemical identification of listeria monocytogenes antigen in tissue sections of experimentally infected rats after pretreatment with dexamethasone (Dexamethasone 전처리후 Listeria monocytogenes를 인공감염시킨 랫드의 조직절편내 균체항원 동정)

  • Sur, Jung-hyang;Kim, Soon-bok
    • Korean Journal of Veterinary Research
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    • v.32 no.1
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    • pp.91-98
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    • 1992
  • Listeria monocytogenes antigens were detected with the avidinbiotinperoxidase complex(ABPC) method in formalin-fixed, paraffin-embedded tissues from experimentally infected rats, mice and guinea pigs. The anti-Lirteria monocytogenes serum used as first antibody was prepared by immunizing rabbits with Listeria monocytogenes serotype 1/2a. Rats, mice and guinea pigs that had been given inoculation of L monocytogenes(serotype 4b, Scott A strain) via intraperitoneally allotted to 3 groups. Rats were pretreated with the dexamethasone(DM-rats) for 7 consecutive days, mice and guinea pigs were inoculated intraperitoneally with L. monocytogenes At necropsy white necrotic foci of the liver, spleen and kidney were seen in mice and DM-rats, whereas not in guinea pigs. Organisms stained by the ABPC method were identified as pleomorphic dark brown staining structures in the livers, spleens and kidneys of mice and DM-rats. They were present in high numbers in center and peripherial regions of necrobiotic and necrotic foci of the liver and spleen as well as in glomerulus of the renal cortex. and liable tool for confirmative diagnosis of these bacterial diseases.

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Effects of Peeling and Sample types on Drying Time and Paeoniflorin Contents of Peony Root (작약근의 박피와 시료형태가 건조시간 및 Paeoniflorin 함량에 미치는 영향)

  • Kim, Ki-Jae;Park, Chun-Hong;Park, So-Deuk;Kim, Jae-Cheol;Park, Kyeng-Sok
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.1
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    • pp.24-28
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    • 2002
  • Effect of pretreatment processing (peeling time, drying temperature, sample type) on the quality of hot air drying peony roots was investigated. Peony roots were peeled for 0, 10, 20, 30, 60, 90 and 120 minute in the peeling machine after water washing. Sample types were whole or cut (thickness of 3mm). Temperatures of hot air drying were 30, 40, 50 and $60^{\circ}C$ The level of water contents in dried sample was $14{\sim}15%$. Drying time was muth reduced as the peeling time, cutting sample types and higher temperature. Contents of paeoniflorin were maintained highest amount (3.48%) in the non-peeling cut sample dried at $30^{\circ}C$ and lowest amount (2.29%) in the 120min-peeling whole one dried at $60^{\circ}C$. Skin color of dried peony roots was heavily discolored in the sample of non-peeling whole type dried at $60^{\circ}C$ and the color was dark brown $({\Delta}E\;was\;46.1)$. When considering shortening of drying time, preservation of active compounds and maintenance of color, the best pretreatment method of drying in peony roots was non-peeling, cut type processing.

Optimization of bio-$H_{2}$ production from acid pretreated microalgal biomass (미세조류로부터 바이오 수소 생산을 위한 산(acid) 전처리의 최적화)

  • Yun, Yeo-Myeong;Jung, Kyung-Won;Kim, Dong-Hoon;Oh, You-Kwan;Shin, Hang-Sik
    • Journal of the Korea Organic Resources Recycling Association
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    • v.20 no.1
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    • pp.78-86
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    • 2012
  • In this study, dark fermentative hydrogen production (DFHP) from acid pretreated microalgal biomass was optimized with via statistical experimental design. Acid concentration and reaction time were varied from 0.1 to 3% (v/w) and 10 to 60 min with substrate concentration of 76 g dry cell weight (dcw)/L and initial pH of 7.4, respectively. During the fermentation, pH was not controlled. The optimal condition was found that at $H_{2}$ yield reached to 37.3 mL $H_{2}/g$ dcw at 1.2% HCl and 48 min. Through regression analysis, it was found that $H_{2}$ yield was well fitted by a quadratic polynomial equation ($R^{2}$=0.95). HCl concentration was the most significant factor influencing DFHP. The results of ANOVA verify that HCl concentration was the most significant factor influencing DFHP.

Pharmacological Studies of Zizyphus Seed Extract on Central Nervous System and Blood Pressure (산조인의 중추신경 및 심혈관계에 대한 약리작용)

  • Ahn, Y.S.;Kim, K.H.;Cho, T.S.;Kim, W.J.;Hong, S.S.
    • The Korean Journal of Pharmacology
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    • v.18 no.1
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    • pp.17-22
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    • 1982
  • Zizyphus seed(Zizyphus vulgaris Lamark var. Spinosus Bunge) has long been used as hypnotics and sedatives in oriental medicine, and it is reported that the Zizyphus seed elicited a variety of pharmacologic actions besides CNS depression. Present study was undertaken to investigate the effects of Zizyphus seed on the central nervous system and on the blood pressure. The effect of Zizyphus seed on the central nervous system was measured by the influence of thiopental sleeping time and by inhibition of chemical convulsion (strychnine and pentylenetetrazol induced). Blood pressure changes by Zizyphus extract and its mode of action were investigated. The ground Zizyphus seed was extracted with hexane and methanol, consecutively and the supernatants were discarded. The precipitate was re-extracted with distilled water and the supernatant was evaporated to a dark-brownish sticky liquid, which was used as Zizyphus seed extract in this study after dissolving in saline prior to experiment. The results are as follows. 1) Zizyphus seed extract caused marked prolongation of the thiopental sleeping time in mice. 2) The chemical convulsion by strychnine and pentylenetetrazol, and the mortality by them in chicks were not affected by pretreatment of Zizyphus seed extract. 3) Zizyphus seed extract produced transient fall of blood pressure in the cat, and this hypotentive effect was blocked partially by atropine but not affected by bilateral vagotomy and/or hexamethonium, nor propranolol and, chlorpheniramine and/or cimetidine. With the above results, it may be suggested that the water extract of Zizyphus seeds contains components producing CNS depression and hypotension. Furthermore it is felt that the cholinergic effect, but not the adrenergic or histaminergic, is partly responsible for the hypotensive effect of Zizyphus seed extract.

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Effects of NaOH and Humic Acid on the UV Photolysis of PCBs (PCBs의 광화학적 연구: NaOH 및 휴믹산 (humic acid, HA)에 의한 분해특성)

  • Shin, Hae Seung;Kim, Jae Hyoun
    • Journal of Environmental Health Sciences
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    • v.40 no.2
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    • pp.147-156
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    • 2014
  • Objectives: This study was carried out to examine whether the apparent photolysis with or without sensitizers [NaOH and humic acid (HA)] was prompted photodegradation of polychlorinated biphenyl (PCB) in aqueous solution. Methods: PCBs photodegradation occurred using fluorescence black lamps at ${\lambda}_{max}=300nm$. PCB congeners were exposed in 10 ppm HA or 0.05N NaOH solutions, to investigate the decreasing profile of PCB concentration with time. The PCBs were then analyzed by gas chromatography/mass spectrometry (GC-MS). Reductive degradation profile of PCB congeners in the presence of both sensitizers under oxygen-saturated protic conditions was described using the wind-rose diagrams. Results: Use of HA or NaOH decreased PCB concentration with time in the dark and on irradiation, indicating that photolysis underwent through reductive dechlorination through energy transfer and possibly with reactive oxygens. The dechlorination was marked by a chromatographic shift, observed in the GC-MS plots. Therefore it is logical to assume that increasing the dose of sensitizers would increase the photodegradation rates of PCBs. The half-lives of pentachloro-PCB (penta-3) in 0.05N NaOH and 10 ppm HA were estimated at about 47 hours and 39 hours, respectively, under the same experimental conditions of photolysis. It was found that the rate of photolysis of pentachloro-PCB in aqueous solution followed apparent first-order kinetics compared to other congeners. Conclusion: Photochemical degradation (using 328 nm UV light) of penta- and hexa-PCBs in HA or alkaline solution is a viable method for pretreatment method. The results are helpful for the further comprehension of the reaction mechanism for photolytic dechlorination of PCBs in aquatic system.

Altered Cultivar Resistance of Kimchi Cabbage Seedlings Mediated by Salicylic Acid, Jasmonic Acid and Ethylene

  • Lee, Young Hee;Kim, Sang Hee;Yun, Byung-Wook;Hong, Jeum Kyu
    • The Plant Pathology Journal
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    • v.30 no.3
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    • pp.323-329
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    • 2014
  • Two cultivars Buram-3-ho (susceptible) and CR-Hagwang (moderate resistant) of kimchi cabbage seedlings showed differential defense responses to anthracnose (Colletotrichum higginsianum), black spot (Alternaria brassicicola) and black rot (Xanthomonas campestris pv. campestris, Xcc) diseases in our previous study. Defense-related hormones salicylic acid (SA), jasmonic acid (JA) and ethylene led to different transcriptional regulation of pathogenesis-related (PR) gene expression in both cultivars. In this study, exogenous application of SA suppressed basal defenses to C. higginsianum in the 1st leaves of the susceptible cultivar and cultivar resistance of the 2nd leaves of the resistant cultivar. SA also enhanced susceptibility of the susceptible cultivar to A. brassicicola. By contrast, SA elevated disease resistance to Xcc in the resistant cultivar, but not in the susceptible cultivar. Methyl jasmonate (MJ) treatment did not affect the disease resistance to C. higginsianum and Xcc in either cultivar, but it compromised the disease resistance to A. brassicicola in the resistant cultivar. Treatment with 1-aminocyclopropane-1-carboxylic acid (ACC) ethylene precursor did not change resistance of the either cultivar to C. higginsianum and Xcc. Effect of ACC pretreatment on the resistance to A. brassicicola was not distinguished between susceptible and resistant cultivars, because cultivar resistance of the resistant cultivar was lost by prolonged moist dark conditions. Taken together, exogenously applied SA, JA and ethylene altered defense signaling crosstalk to three diseases of anthracnose, black spot and black rot in a cultivar-dependent manner.

Control of Algal Blooms in Eutrophic Water Using Porous Dolomite Granules

  • Huh, Jae-Hoon;Choi, Young-Hoon;Lee, Shin Haeng;Cheong, Sun Hee;Ahn, Ji Whan
    • Journal of the Korean Ceramic Society
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    • v.54 no.2
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    • pp.108-113
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    • 2017
  • The use of aluminum-based coagulants in water pretreatment is being carefully considered because aluminum exposure is a risk factor for the onset of Alzheimer's disease. Lightly burned-dolomite kiln dust (LB-DKD) was evaluated as an alternative coagulant because it contains high levels of the healthful minerals calcium and magnesium. An organic pore forming agent (OPFA) was incorporated to prepare porous granules after OPFA removal through a thermal decomposition process. A spray drying method was used to produce uniform and reproducible spherical granules with low density, since fine dolomite particles have irregular agglomeration behavior in the hydration reaction. The use of fine dolomite powder and different porosity granules led to a visible color change in raw algae (RA) containing water, from dark green to transparent colorlessness. Also, dolomite powders and granules exhibited a mean removal efficiency of 48.3% in total nitrogen (T-N), a gradual increase in the removal efficiency of total phosphorus (T-P) as granule porosity increased. We demonstrate that porous dolomite granules can improve the settling time and water quality in summer seasons for the emergent treatment of excessive algal blooms in eutrophic water.

Anther Culture of Cornus officinalis Sieb. et Zucc. (산채막(山菜莫)의 약배양(約培養)에 환한 연구(硏究))

  • Kwon, Tae-Oh;Kim, Tai-Soo;Lee, Seung-Yeob
    • Korean Journal of Medicinal Crop Science
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    • v.3 no.3
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    • pp.233-239
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    • 1995
  • The effects of media, growth regulators, low-temperature treatments, culture temperature and light were investigated to improve the callus induction and growth in the anther culture of Comus officinalis Sieb. et Zucco. The frequency of callus induction was more effective on WPM medium than MS medium, and it was highest as 54% in WPM medium supplemented with Img/L NAA. Callus growth was stimulated on MS medium supplemented with 2mg/L NAA. Effect of temperature and light on the callus induction and growth was highest as 62% in the treatment for 16/8 hrs. (light/dark) at $25^{\circ}C$ Ef­fect of low - temperature treatment on callus induction was highest as 19. 5% in the treatment for 36 hrs. at $4^{\circ}C$. For organization, green cells and rootings were promoted on MS medium supplemented with O. 5mg/L 2,4-D and 1 mg/L kinetin. The prevention of callus browning was effective on the medium con­taining $3{\sim}5mg/L$ ABA or 5mg/L $AgNO_3$. The supplement of ABA or $AgNO_3$,were maintained callus ac­tivity for 4-5 weeks and they were promoted the development of green cells.

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