• Title/Summary/Keyword: Concentration control

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Short-term changes of phytoplankton communities after nutrient addition and establishment of stable mass culture condition to prepare the type approval test of USCG Phase-II in mesocosm enclosure (메소코즘에서 USCG phase-II 형식승인 대비 영양염 첨가에 따른 식물플랑크톤 대량 배양조건 확립 및 군집구조의 단주기변화)

  • Baek, Seung Ho;Lee, Min Ji;Shin, Kyoungsoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.4
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    • pp.34-42
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    • 2016
  • In order to prepare for the type approval test for the United States Coast Guard (USCG) Phase-II of Ballast Water Treatment System (BWTS), a phytoplankton mass culture was conducted in a mesocosm enclosure. We evaluated the response of the phytoplankton community after nutrient addition (+N, +P, and +NP) and investigated the development of the species with increasing culture time. After nutrient dosing, the phytoplankton population significantly (p < 0.05) increased from day 1 to day 3, depending on the nutrient treatments In particular, the specific growth rate of the phytoplankton community in the case of +NP treatment and + N treatment were estimated to be $2.47d^{-1}$ and $1.98d^{-1}$, respectively. The phytoplankton population density in the case of + NP treatment was approximately 50 times higher than that of the control group, suggesting that these treatments could be useful for mass culturing phytoplankton (> 75% of natural community) for the approval regulation of USCG Phase-II. In the phytoplankton community of the mesocosm, Pseudo-nitzchia spp. dominated in the logarithmic growth phase. The cell density decreased significantly (p < 0.05) with increasing time, coinciding with the nutrient limitation. At that time, the dominance of Pseudo-nitzchia spp. shifted to that of Cylindrotheca closterium. Therefore, the optimum nutrient concentration ($N:30{\mu}M$, $P:3{\mu}M$) and reasonable harvesting time (after 3 days in summer) found in this study for the mass culturing of phytoplankton may be helpful to meet the USCG Phase-II biological criteria to be used in BWTS.

The Clinical and Cost Effectiveness of Medical Nutrition Therapy for Patients with Type 2 Diabetes Mellitus (제2형 당뇨병환자에서 임상영앙치료의 임상적 효과와 비용효과 연구)

  • Cho, Youn-Yun;Lee, Moon-Kyu;Jang, Hak-Chul;Rha, Mi-Yong;Kim, Ji-Young;Park, Young-Mi;Sohn, Cheong-Min
    • Journal of Nutrition and Health
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    • v.41 no.2
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    • pp.147-155
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    • 2008
  • Medical nutrition therapy (MNT) is considered a keystone of medical treatment of chronic diseases. However, only few studies have evaluated medical and economical outcome of MNT. The study was performed on the patient with type 2 diabetes mellitus to evaluate the effect of clinical and cost-effective outcomes of MNT. Subjects from two general hospitals were randomly assigned to two different groups; One receiving basic nutritional education (BE) (n = 35), and the other receiving intensive nutritional education (IE) (n = 32) for a 6-month clinical trial. The group which received BE had a single visit with a dietitian, while the other group which received IE had an initial visit with a dietitian addition to two visits during the first 4 weeks of the study periods. Anthropometric parameters, blood components, and dietary intake were measures at the beginning of study period and after 6 month. Cost-effective analysis included direct labor costs, educational materials and medication cost difference during 6 months. After 6 month, subjects from IE group showed significant reduction of body weight (p <0.05) and systolic blood pressure (p <0.05), whereas BE group did not show any significant changes. Result from biochemical indices showed glycated hemoglobin concentration was significantly reduced by 0.7% (p <0.05) only in the IE group. The ratio of energy intake to prescribed energy intake decreased significantly in both groups (p <0.05). Mean time taken for a dietitian to educate the subject was 67.9 ${\pm}$ 9.3 min/person for BE group, while 96.4 ${\pm}$ 12.2 min/person for IE group. Mean number of educational materials was 1.9 ${\pm}$ 0.7/person for BE group and 2.5 ${\pm}$ 0.7/person for IE group. Change in glycated hemoglobin level along the 6 month period of study can be achieved with an investment of \88,510/% by implementing BE and \53,691/% by implementing IE. Considering the net cost-effect of blood glucose control and HbA Ic, IE which provides MNT by dietitian had a cost efficiency advantage than that of BE. According to this study, MNT provided by dietitian had a significant improvements in medical and clinical outcomes compared to that of BE intervention. Therefore, MNT protocol should be performed by systemic intensive nutrition care by dietitian in clinical setting to achieve good therapeutic results of DM with lower cost.

Effect of Fermented Brown Seaweed Waste (FBSW) on in vitro Rumen Microbial Fermentation (발효 미역부산물이 반추위 발효특성에 미치는 영향)

  • Hong, Zhong-Shan;Lee, Hong-Gu;Lee, Zhe-Hu;Jin, Yong-Cheng;Lee, Sang-Bum;Kang, Han-Suck;Choi, Yun-Jaie
    • Journal of Animal Science and Technology
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    • v.53 no.4
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    • pp.349-356
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    • 2011
  • This study was conducted to investigate the effects of brown seaweed waste (BSW) fermented with DS-01 microbe on in vitro rumen microbial fermentation. In in vitro trial, three different diets supplemented with 2%, 4%, 6% BSW fermented with DS-01 either for one month or two months was tested at 3 h, 6 h, 9 h, 12 h, and 24 h incubation. The chemical composition (CP, EE, CF, and ash) between brown seaweed waste (BSW) and fermented BSW (FBSW) were not different. The contamination of pathogenic microbes was not detected in FBSW. The pH value tended to be higher with 6% level of supplementation of FBSW for one month than other treatments. The pH at 24 h was significantly higher in FBSW than that of treatments without FBSW (p<0.05). In FBSW for two months, the pH value in 6% FBSW at 3 h in vitro fermentation tended to be higher than 2% or 4% FBSW treatments (p=0.0540), but there were no differences in other fermentation times. Although the concentration of $NH_3$-N of BSW fermented for one month was higher than control at 3 h (p<0.05), the volatile fatty acid values were significantly increased in 4 and 6% FBSW fermented for one month at 6 h incubation (p<0.05). In BSW fermented for two months, the volatile fatty acid values were significantly decreased in 6% treatment at 9 h (p<0.05). As a result of in vitro trial, it was recommended that the 2~4% supplementation level of brown seaweed waste fermented with DS-01 microbe for two months could be utilized for in vivo trial in ruminants.

Evaluation of Bio-starch from Corn Processing to Replace Dried-Whey in Weaned Pigs (이유자돈에서 건조 유청 대체를 위한 옥수수 전분 가공제품 Bio-starch의 급여 평가)

  • Shin, Seung-Oh;Yoo, Jong-Sang;Lee, Je-Hyun;Jang, Hae-Dong;Kim, Hyo-Jin;Huang, Yan;Chen, Ying he;Cho, Jin-Ho;Kim, In-Ho
    • Journal of Animal Science and Technology
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    • v.50 no.4
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    • pp.499-508
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    • 2008
  • This study was conducted to evaluate the effect of bio-starch from corn processing to replace dried whey in weaned pigs. A total of 120 crossbred [(Landrace×Yorkshire)×Duroc] pigs were weaned at 21 days of age weighing 6.01±0.34 kg in average. Five week feeding trial consisted of phase 1(0~2 wks) and phase 2(3~5 wks). Dietary treatments included 1) CON(basal diet), 2) BS5(whey 5%, partial substitution of bio-starch), 3) BS10(whey 10%, partial substitution of bio-starch) and 4) BS15(whey 15%, partial substitution of bio-starch). There were four dietary treatments with six replicate pens per treatment and five pigs per pen. During the overall period, there were no significant differences in the ADG(average daily gain) and gain/feed ratio among the treatments(P>0.05). However, the ADFI(average daily feed intake) was higher in BS5 and BS15 treatments than in CON treatment(P<0.05). At the 2nd week, dry matter and nitrogen digestibility were increased(quadratic effect, P=0.03 and P=0.01, respectively; cubic effect, P<0.001 and P=0.01, respectively) with the highest at 10% of bio-starch inclusion in the diets. At the last week of the experiment, dry matter, nitrogen and energy digestibility were increased(P<0.05) with the highest at 5% of bio-starch inclusion in the diets. At the 2nd week total protein concentration was increased(linear effect, P=0.04; cubic effect, P=0.01) with the highest at 10% of bio-starch inclusion in the diets. Also, BUN(blood urea nitrogen) was increased(linear effect, P=0.01) as the level of bio-starch inclusion increased in the diets. Fecal consistency score was inclined to lowers CON treatment than other treatments. In conclusion, the result of trial indicates that bio-starch can be included at the level of 5~10% of weaning pig diet replacing part of the dried-whey, and digestibilities were positively affected by bio-starch at growth stage.

Characteristics of Pesticide Runoff and Persistence on Agricultural Watersheds in Korea (영농지역에서 작물재배 형태에 따른 농약의 잔류성과 유출특성)

  • Park, Byung-Jun;Kwon, Oh-Kyung;Kim, Jin-Kyoung;Kim, Jin-Bea;Kim, Jin-Ho;Yoon, Soon-Kang;Shim, Jae-Han;Hong, Moo-Gi
    • Korean Journal of Environmental Agriculture
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    • v.28 no.2
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    • pp.194-201
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    • 2009
  • To evaluate the exposure of non-point source pesticide pollution in agricultural watershed and to investigate pesticide distribution and runoff from agricultural land, paddy field, upland and orchard, this experiment was carry out during crop growing seasons. The pesticide were detected twenty pesticides fungicide 4, insecticide 10, herbicide 6) in water of Neungchon agricultural watershed and detection concentrations were range 0.008${\sim}$7.59 ppb. Most of the detection pesticides were using pesticides to rice paddy fields to control fungi, insects, weeds. During the crop cultivation, the pesticide were detected total thirty pesticides by pepper field soil 6, orchard soil 4, sesame field soil 3 and rice paddy field soil 5, and pesticide concentrations were range 0.001${\sim}$0.109 ppm. Especially the herbicides were detected mainly in May and June in the stream water. The pesticide were detected thirty pesticides by fungicide 2, insecticide 6, herbicide 5 in water of Jungam Koseong agricultural watershed and detection concentrations were range 0.01${\sim}$7.21 ppb. In regard to the detected pesticides, the concentration of individual pesticides measured in surface water of the study areas never exceeded guidelines for agriculture chemicals concerning water quality-effluent from paddy fields in Japan (Katayama, 2003). Runoff rate of pesticides was range 0.07${\sim}$3.06 % from Kongju agricultural land to watershed after applied pesticides.

Quantitative Measurement of Carbon Dioxide Consumption of a Whole Paprika Plant (Capsicum annumm L.) Using a Large Sealed Chamber (대형 밀폐 챔버를 이용한 파프리카(Capsicum annumm L.) 개체의 이산화탄소 소비량 측정 및 정량화)

  • Shin, Jong-Hwa;Ahn, Tae-In;Son, Jung-Eek
    • Horticultural Science & Technology
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    • v.29 no.3
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    • pp.211-216
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    • 2011
  • This study was carried out to clarify precise $CO_2$ demands of paprika plants (Capsicum annumm L.) by measuring photosynthesis rates of the leaves in high, low positions, and the $CO_2$ consumption of a whole plant in a large sealed chamber. A photosynthesis measuring system (LI-6400) was used to measure the photosynthetic rates of the leaves located in different positions. A large sealed chamber that can control inside environmental factors was developed for measuring $CO_2$ consumption by a whole paprika plant. With increase of radiation, photosynthetic rates of the leaves in higher position became larger than those in lower position. The $CO_2$ consumption by the plant was estimated by using decrement of $CO_2$ concentration from initial level of 1500 ${\mu}mol{\cdot}mol^{-1}$ in the chamber with increase of integrated radiation. A regression model for estimating $CO_2$ consumption by the plant (leaf area = 7,533.4 $cm^2$) was expressed with integrated radiation (x) and was suggested as $y=-0.06234+3.671^*x/(2.589+x)$ ($R^2=0.9966^{***}$). The photosynthetic rate of the whole plant measured in the chamber was 3.4 ${\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$ under 300 ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light intensity, which is in-between photosynthetic rates of the leaves in high and low positions. For this reason, some differences between required and supplied $CO_2$ amounts in greenhouses might occur when depending too much on photosynthetic rates of leaves. Therefore, we can estimate more accurately $CO_2$ amount required in commercial greenhouses by using $CO_2$ consumption model of a whole plant obtained in this study in addition to leaf photosynthetic rate.

Growth Characteristics and Nutrient Uptake of Kalanchoe Plants (Kalanchoe blossfeldiana 'Marlene') at Different Light Intensities and Nutrient Strengths in Ebb and Flow Subirrigation Systems (Ebb and Flow 저면관수 시스템에서 광강도와 양액농도에 따른 칼랑코에(Kalanchoe blossfeldiana 'Marlene') 생육 및 양분흡수 특성)

  • Noh, Eun-Hee;Jun, Ha-Joon;Son, Jung-Eek
    • Horticultural Science & Technology
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    • v.29 no.3
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    • pp.187-194
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    • 2011
  • The objective of this study was to determine the effects of light intensity and electrical conductivity (EC) of nutrient solution on the growth and nutrient uptake of potted kalanchoe plants (Kalanchoe blossfeldiana 'Marlene') with growth stage in ebb and flow subirrigation systems. The plants were grown at four ECs of 0.5, 1.0, 1.5, and 2.0 $dS{\cdot}m^{-1}$ for seedling stage and four ECs of 1.0, 1.5, 2.0, and 3.0 $dS{\cdot}m^{-1}$ for short day stage under three daily photosynthetic photon flux (PPF) of 6.5, 10.3, 18.2 $mol{\cdot}m^{-2}{\cdot}d^{-1}$. At seedling stage, plant height was the longest under the lowest light intensity, and particularly dry weights and leaf areas were the highest at PPF 10.3 $mol{\cdot}m^{-2}{\cdot}d^{-1}$. Dry weights and leaf areas were the highest at EC 1.5 $dS{\cdot}m^{-1}$ regardless of light intensity. At short day exposure, plant height was the longest under the lowest light intensity. Dry weights, leaf areas, and number of pedicels of the plants significantly increased as light intensity increased. Under all light intensity conditions, dry weights, leaf areas, and number of pedicles increased until EC becomes to 1.0 - 2.0 $dS{\cdot}m^{-1}$. And after reached the highest at EC 2.0 $dS{\cdot}m^{-1}$, they decreased at EC 3.0 $dS{\cdot}m^{-1}$. By comparing the ion uptakes at EC 1.5 $dS{\cdot}m^{-1}$ of seedling stage and EC 2.0 $dS{\cdot}m^{-1}$ of short day stage in which the plants grew better, we confirmed that ion balance of nutrient solution among $NO_3{^-}$-N, $H_2PO_4{^-}$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were significantly changed at short day stage compared to seedling stage. For better growth of the plants, both ion balance and EC of nutrient solution should be considered under different light intensities at short day stage while control of EC is enough at seedling stage.

Effect of NO Treatment during Shelf Life of 'Hayward' Kiwifruit after Storage at Cold Temperature (Nitric Oxide 처리가 저온 저장된 키위과실의 상온 유통 중 품질에 미치는 영향)

  • Eum, Hyang Lan;Lee, Eun Jin;Hong, Sae Jin
    • Horticultural Science & Technology
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    • v.32 no.5
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    • pp.666-672
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    • 2014
  • The effect of nitric oxide (NO) treatment on the quality of kiwifruit, cv. Hayward, was studied at room temperature after cold storage for one or three months at $0^{\circ}C$. Kiwifruits cold-stored for one month were treated with $200{\mu}L{\cdot}L^{-1}$ NO and subsequently transferred to room temperature to monitor quality changes over the course of their shelf life. Weight loss was high in fruits not treated with NO. Ethylene production was delayed for two days by NO treatment, and respiration rate was reduced to less half than that of the control. The kiwifruits stored for three months were treated with $N_2$ and 100, 200, or $500{\mu}L{\cdot}L^{-1}$ NO, or air alone. The highest weight loss was observed in kiwifruit treated with $100{\mu}L{\cdot}L^{-1}$ NO. While ethylene production was high in fruits treated with $100{\mu}L{\cdot}L^{-1}$ NO and without the treatment, it was relatively low in the kiwifruit treated with 200 and $500{\mu}L{\cdot}L^{-1}$ NO. Firmness was abruptly decreased in fruits not treated with NO, while the kiwifruit exposed to $200{\mu}L{\cdot}L^{-1}$ NO maintained the s ame level of f irmness for 9 days a t room t emp erature. In addition, growth o f Botrytis cinerea was inhibited by NO as compared with the air and $N_2$ treatments. Our findings indicate that NO can be used effectively for prolonging shelf life and maintaining fruit quality during distribution after cold storage. The optimum NO concentration for cold-stored kiwifruits was found to be $200{\mu}L{\cdot}L^{-1}$.

The Electrochemical Chlorination for Marine Plankton Community Disinfection (해양 플랑크톤 군집의 전기분해 염소소독 효과)

  • Kang, Jung-Hoon;Shin, Kyoung-Soon;Hyun, Bong-Gil;Jang, Min-Chul;Kim, Eun-Chan;Chang, Man
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.3
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    • pp.127-137
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    • 2007
  • To confirm whether or not the Electrochemical Disinfection System (EDS) meet with the D-2 regulation established by IMO (International Maritime Organization), the biological treatment efficacy of the EDS was assessed using three groups of natural marine plankton (bacteria, $10-50\;{\mu}m$ and $>50\;{\mu}m$ sized organisms). Influent water was passed through the EDS under the flow velocity ($23.8\;m^3/hr$) and test design was consisted of control (no treatment) and experimental (10 ppm and 30 ppm) condition for total residual chlorine (TRC). And the biological condition of the influent water followed the standards established by the guidelines for the approval of ballast water management systems. The disinfection efficacy of the $10-50\;{\mu}m$ sized organisms (phytoplankton) was assessed by three kinds of measurements using photomicroscope, epifluorescence microscope and fluorometer (fumer Designs 10-AU). After being passed through the EDS, all motile phytoplankton lost their motility under photomicroscope, the colour of chlorophyll fluorescence fumed from red into green under epifluorescence, and the high chlorophyll fluorescence (Expt. 1: 6.95, Expt. 2: 7.11) detected by fluorometer decreased into value not detected. These results indicated phytoplankton community was totally killed after electrochemical disinfection treatment. Survivorship of the larger organisms than $50\;{\mu}m$ was determined based on the appendage's movement under a stereomicroscope. Natural assemblage collected from ambient seawater was killed shortly after being passed through the EDS, whereas some Artemia remained alive. However, no live Artemia was found after 24 hour further exposure to each TRC concentration (10 and 30 ppm) under darkness. After electrochemical treatment, the target bacteria such as aerobes, coliform and Escherichia coli were completely killed on the basis of CFU (colony forming unit) on Petrifilm plate ($3\;M^{TM}$) after 48 hr incubation. Moreover, no regrowth was found in the three groups of plankton during five days under additional exposure to the treated water. These results indicated that the disinfection efficiency of the EDS on the three groups of plankton satisfy D-2 regulation.

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The Responses of Particulate Phosphorus Exposed to the Fresh Water in Marine Sediment (담수화로 인한 퇴적물 내 입자성 인의 거동에 관한 실험적 연구)

  • Ji, Kwang-Hee;Jeong, Yong-Hoon;Kim, Hyun-Soo;Yang, Jae-Sam
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.12 no.2
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    • pp.84-90
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    • 2009
  • We incubated marine columnar sediments at $25^{\circ}C$ for 230 days to simulate the responses of phosphorus in the sediment which was exposed to freshwater. The incubation was composed of three different treatments (FW: freshwater, FWA: freshwater under anoxic condition, and SW: seawater as a Control). Six particulate fractions of phosphorus in sediment were obtained through sequential extraction and, for comparison, phosphate concentrations in porewater and superlying water were also determined. After the incubation, evidently higher concentrations of phosphate were found in FW and FWA compared to SW. Mass extinction of living organisms in marine sediment from freshwater shock and consequent decay of their corps probably contributed such high phosphate spike in the overlying water. Higher concentrations of BD-P(lron-bound P) were found in FW compared to SW. After exposure to the freshwater, we could determine that penetration depth of dissolved oxygen in marine sediment will be deeper. A result of increases of ferrous compounds in freshwater where contained less sulfide has been obtained. Because of these phenomena, BD-P was increased in FW. On the contrary, BD-P was decreased in FWA since poor dissolved oxygen concentration. In FWA, total amount of Leachable P(SUM of LOP) has been remarkably increased through the experiment, which strongly suggested the easy conversion of the leachable P into reactive P. This experiment has shown that most of diverse P species in marine sediment were leachable under freshwater and low oxygen condition. Therefore reclamation of natural tidalfalt and consequent freshwater introduction seems to trigger the conversion of diverse P-species to leachable P in the marine sediments, which will exert high benthic load of phosphate to the overlying water.

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