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Long-term Variation and Flux of Organic Carbon in the Human-disturbed Yeongsan River, Korea (영산강의 유기물 플럭스와 장기변동에 대한 연구)

  • CHO, HYEONG-CHAN;CHO, YEONG-GIL
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.22 no.4
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    • pp.187-198
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    • 2017
  • Dissolved and particulate organic carbon concentrations and fluxes were measured and estimated for the Yeongsan River during 2006~2015. The dissolved organic carbon (DOC) concentrations ranged from 2.49 to $4.39mg{\cdot}C/L$ with a variance of 30.1% (${\sigma}_x/\bar{x}$), and showed a simple correlation to algal bloom and precipitation. The particulate organic carbon (POC) concentrations had gradually decreased from 6.68 to $0.19mg{\cdot}C/L$ for 10 years, and changed definitely with weir construction in 2011. Based on the relationships between POC and suspended particulate matters and between POC and chlorophyll-a, we found out that the distinct variation of the origin and composition of POC was caused by stagnation and screening effect of the dammed river. The total organic carbon (TOC) concentrations dropped to 52.3% (from 8.26 to $3.94mg{\cdot}C/L$) as the POC concentrations diminished to more than 94.8% after weir construction, in which the DOC forms up to 90.9%. The fluxes of TOC, based on the relationship between the annual TOC concentration and the discharge of Yeongsan dike sluice, were $2.56{\sim}19.41{\times}10^9g{\cdot}C/yr$, and showed a great deal of variability in 2011. Since then the TOC flux dropped to $5.40{\times}10^9$ (2011~2015) from $14.54{\times}10^9g{\cdot}C/yr$ (2006~2010). These results suggest that the weirs trapped annually $1.83{\times}10^9g{\cdot}C$ on a river bed, but released in great levels of dissolved organic form at their exits.

Effect of Forage to Concentrate Ratio and Monensin Supplementation on cis-9, trans-11 Conjugated Linoleic Acid and trans-11 Octadecenoic Acid Concentrations of Ruminal Contents and Plasma in Sheep

  • Zhang, Yuzhi;Kong, Xianghao;Zhu, Xiaoping;Wang, Runlian;Yan, Yichai;Jia, Zhihai
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.5
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    • pp.699-704
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    • 2006
  • Twenty-four cannulated Small-tailed Han${\times}$Poll Dorset wethers (BW $47.5{\pm}2.1kg$) were used to determine the effects of forage to concentrate ratio (40:60 vs. 70:30), monensin supplementation (0, 15 or 30 ppm, DM basis) and interactions of these two factors on cis-9, trans-11 conjugated linoleic acid (cis-9, trans-11 CLA) and trans-11 octadecenoic acid (trans11-$C_{18:1}$) concentrations in ruminal contents and plasma in sheep. The experiment was designed as a $2{\times}3$ factorial. The diet contained Chinese wild rye grass hay (Aneurolepidium Chinese), cracked corn, soybean meal, NaCl, limestone and trace mineral premix. Dietary crude fat and linoleic acid ($C_{18:2n-6}$) were adjusted with soybean oil to about 7.0% and 24.0 mg/g (DM basis), respectively. High forage diets increased (p<0.001) the concentrations of trans11-$C_{18:1}$ and cis-9, trans-11 CLA in ruminal contents and plasma. Monensin supplementation increased (p<0.001) the concentration of trans11-$C_{18:1}$ in ruminal contents, but had no effect on that of cis-9, trans-11 CLA. Concentrations of trans11-$C_{18:1}$ (p<0.019) and cis-9, trans-11 CLA (p<0.022) in plasma increased with dietary monensin levels. Interactions of forage: concentrate ratio and monensin level tended to affect the concentrations of trans11-$C_{18:1}$ (p<0.091) and $C_{18:2n-6}$ (p<0.083) in ruminal contents. Increasing forage levels increased the concentrations of trans11-$C_{18:1}$ and cis-9, trans-11 CLA in the rumen. Supplementing with monensin increased the ruminal production of trans11-$C_{18:1}$ and concentrations of trans11-$C_{18:1}$ and cis-9, trans-11 CLA in plasma.

Quality Change of Red Meat by Chlorine Dioxide Treatment during Storage (이산화염소 처리에 의한 적색육의 저장 중 품질변화)

  • Lee, Seung-Hwan;Shin, Hee-Young;Ku, Kyoung-Ju;Jin, You-Young;Jeon, So-Jeong;Chae, Hyeon-Seok;Song, Kyung-Bin
    • Korean Journal of Food Science and Technology
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    • v.39 no.2
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    • pp.222-227
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    • 2007
  • The effects of chlorine dioxide ($ClO_2$) treatment on the quality changes of pork and beef were examined. Pork belly and beef tenderloin samples were treated with 30, 50, and 100 ppm of $ClO_2$ solution, respectively, and stored at $4{\pm}1^{\circ}C$. The $ClO_2$ treatment of pork and beef during storage decreased total aerobic bacteria, yeast, and mold counts with increasing concentration of $ClO_2$. The total aerobic bacterial counts for the pork belly treated at 100 ppm of $ClO_2$ increased from 1.48 log CFU/g immediately following treatment to 4.73 log CFU/g after 10 days, while the control increased from 2.19 log CFU/g to 6.22 log CFU/g. For the beef tenderloin, the total aerobic bacterial counts increased from 3.98 log CFU/g to 5.97 log CFU/g after 10 days, and a $ClO_2$ treatment at 100 ppm resulted in an increase from 3.13 log CFU/g to 4.73 log CFU/g. The pH and volatile basic nitrogen (VBN) values of the $ClO_2-treated$ pork and beef, as well as the control groups, increased during storage, and there were no significant changes among the treatments. The thiobarbituric acid reactive substance (TBARS) values of the $ClO_2-treated$ samples were slightly higher than those of the control. Sensory evaluation results showed that the pork and beef samples were not acceptable at day 8 and 6 of storage, respectively. These results indicate that $ClO_2$ treatment could be useful in improving microbial safety and quality of both pork and beef.

Interrelationship between Dopaminergic Receptors and Catecholamine Secretion from the Rat Adrenal Gland (흰쥐 부신에서 카테콜아민 분비작용과 도파민 수용체간의 상관성)

  • Lim, Dong-Yoon;Yoon, Joong-Keun;Moon, Baek
    • The Korean Journal of Pharmacology
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    • v.30 no.1
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    • pp.87-100
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    • 1994
  • It has been known for some time that dopamine-containing cells are existed in sympathetic ganglia, i.e., small, intensely fluorescent cells. However, its role and mechanism of action as a peripheral neurotransmitter are poorly understood so far. In the present study, an attempt was made to examine the effect of apomorphine, which is known to be a selective agonist of dopaminergic $D_2$. receptor on secretion of catecholamines (CA) from the isolated perfused rat adrenal gland. The perfusion of a low concentration of 10uM apomorphine into an adrenal vein for 20 min produced significant reduction in CA secretion induced by 5.32 mM ACh, 56 mM KCl, 100 uM DMPP and 100 uM McN-A-343. Increasing apomorphine concentration to 30 uM led to more markedly decreased CA secretion as compared to the case of 10 uM apomorphine and also did inhibit clearly CA release by $10^{-5}M$ Bay-K-8644. Furthermore, in adrenal glands preloaded with a higher dose of 100 uM apomorphine, CA releases evoked by ACh, excess $K^+$, DMPP and McN-A-343 were almost abolished by the drug. The perfusion of $3.3{\pm}10^{-5}M$ metoclopramide, which is well-known as a selective dopaminergic $D_2$ antagonist, produced significantly inhibitory effect of CA release by ACh, DMPP and McN-A-343 but did not affect that by excess $K^+$. However, preloading of 30uM apomorphine in the presence of metoclopramide did not modify the CA secretory effect of excess $K+$ and DMPP. These experimental results demonstrate that apomorphine causes dose-dependent inhibition of CA secretion by cholinergic receptor stimulation and also by membrane depolarization from the isolated perfused rat adrenal gland, suggesting that these effects appear to be exerted by inhibiting influx of extracellular calcium into the rat adrenal medullary chromaffin cells through activation of inhibitory dopaminergic receptors.

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The Characteristics of Particulate PAHs Concentrations at a Roadside in Seoul (서울시 도로변에서 입자상 다환방향족탄화수소의 농도 특성)

  • Lee, Ji-Yi;Kim, Yong-Pyo;Bae, Gwi-Nam;Park, Su-Mi;Jin, Hyun-Chur
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.2
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    • pp.133-142
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    • 2008
  • Five intensive measurements of particulate PAHs were made at a roadside in Seoul from May 2005 to June 2006. The average concentration of particulate PAHs was $15.1{\pm}10.6ng\;m^{-3}$. The high concentrations of particulate fluoranthene and pyrene were observed in November 2005 due to the influence of the lower ambient temperature. Compared to the previous results at tunnel and ambient sites in Seoul, larger fraction of the high molecular PAH compounds which consist with five or six benzene rings, was observed at a roadside. This might indicate high influence of vehicle emission at a roadside. The distribution of diagnostic ratios for specific PAH compounds indicated that the influence of vehicular emission, especially diesel vehicular emission seems to be high at a roadside.

Compounds Obtained from Sida acuta with the Potential to Induce Quinone Reductase and to Inhibit 7,12-Dimethylbenz-[a]anthracene-Induced Preneoplastic Lesions in a Mouse Mammary Organ Culture Model

  • Jang, Dae-Sik;Park, Eun-Jung;Kang, Young-Hwa;Su, Bao-Ning;Hawthorne, Michael-E.;Vigo, Jose-Schunke;Graham, James-G.;Cabieses, Fernando;Fong, Harry H.S.;Mehta, Rajendra-G.;Pezzuto, John-M.;Kinghorn, A.-Douglas
    • Archives of Pharmacal Research
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    • v.26 no.8
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    • pp.585-590
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    • 2003
  • Activity-guided fractionation of the EtOAc-soluble extract of the whole plants of Sida acuta using a bioassay based on the induction of quinone reductase (OR) in cultured Hepa 1c1c7 mouse hepatoma cells, led to the isolation of ten active compounds of previously known structure, quindolinone (1), cryptolepinone (2), 11-methoxyquindoline (3), N-trans-feruloyltyramine (4), vomifoliol (5), loliolide (6), 4-ketopinoresinol (7), scopoletin (8), evofolin-A (9), and evofolin-B (10), along with five inactive compounds of known structure, ferulic acid, sinapic acid, syringic acid, ($\pm$)-syringaresinol, and vanillic acid. These isolates were identified by physical and spectral data measurement. A new derivative of quindolinone, 5,10-dimethylquindolin-11-one (1a) was synthesized and characterized spectroscopically. Of the active substances, compounds 1-3 and 1a exhibited the most potent QR activity, with observed CD (concentration required to double induction) values ranging from 0.01 to 0.12 $\mu$ g/mL. Six compounds were then evaluated in a mouse mammary organ culture assay, with cryptolepinone (2), N-trans-feruloyltyramine (4), and 5,10-dimethylquindolin-11-one (1a) found to exhibit 83.3, 75.0, and 66.7% inhibition of 7,12-dimethylbenz[a]anthracene-induced preneoplastic lesions, respectively, at a dose of 10 $\mu\textrm{g}$/mL.

A prediction study on the number of emergency patients with ASTHMA according to the concentration of air pollutants (대기오염물질 농도에 따른 천식 응급환자 수 예측 연구)

  • Han Joo Lee;Min Kyu Jee;Cheong Won Kim
    • Journal of Service Research and Studies
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    • v.13 no.1
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    • pp.63-75
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    • 2023
  • Due to the development of industry, interest in air pollutants has increased. Air pollutants have affected various fields such as environmental pollution and global warming. Among them, environmental diseases are one of the fields affected by air pollutants. Air pollutants can affect the human body's skin or respiratory tract due to their small molecular size. As a result, various studies on air pollutants and environmental diseases have been conducted. Asthma, part of an environmental disease, can be life-threatening if symptoms worsen and cause asthma attacks, and in the case of adult asthma, it is difficult to cure once it occurs. Factors that worsen asthma include particulate matter and air pollution. Asthma is an increasing prevalence worldwide. In this paper, we study how air pollutants correlate with the number of emergency room admissions in asthma patients and predict the number of future asthma emergency patients using highly correlated air pollutants. Air pollutants used concentrations of five pollutants: sulfur dioxide(SO2), carbon monoxide(CO), ozone(O3), nitrogen dioxide(NO2), and fine dust(PM10), and environmental diseases used data on the number of hospitalizations of asthma patients in the emergency room. Data on the number of emergency patients of air pollutants and asthma were used for a total of 5 years from January 1, 2013 to December 31, 2017. The model made predictions using two models, Informer and LTSF-Linear, and performance indicators of MAE, MAPE, and RMSE were used to measure the performance of the model. The results were compared by making predictions for both cases including and not including the number of emergency patients. This paper presents air pollutants that improve the model's performance in predicting the number of asthma emergency patients using Informer and LTSF-Linear models.

Effects of Chitosan on Body Weight Gain, Growth Hormone and Intestinal Morphology in Weaned Pigs

  • Xu, Yuanqing;Shi, Binlin;Yan, Sumei;Li, Tiyu;Guo, Yiwei;Li, Junliang
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.10
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    • pp.1484-1489
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    • 2013
  • The study was conducted to determine the effects of chitosan on the concentrations of GH and IGF-I in serum and small intestinal morphological structure of piglets, in order to evaluate the regulating action of chitosan on weaned pig growth through endocrine and intestinal morphological approaches. A total of 180 weaned pigs (35 d of age; $11.56{\pm}1.61kg$ of body weight) were selected and assigned randomly to 5 dietary treatments, including 1 basal diet (control) and 4 diets with chitosan supplementation (100, 500, 1,000 and 2,000 mg/kg, respectively). Each treatment contained six replicate pens with six pigs per pen. The experiment lasted for 28 d. The results showed that the average body weight gain (BWG) of pigs was improved quadratically by dietary chitosan during the former 14 d and the later 14 d after weaned (p<0.05). Furthermore, dietary supplementation of chitosan tended to quadratically increase the concentration of serum GH on d 14 (p = 0.082) and 28 (p = 0.087). Diets supplemented with increasing levels of chitosan increased quadratically the villus height of jejunum and ileum on d 14 (p = 0.089, p<0.01) and 28 (p = 0.074, p<0.01), meanwhile, chitosan increased quadratically the ratio of villus height to crypt depth in duodenum, jejunum and ileum on d 14 (p<0.05, p = 0.055, p<0.01) and 28 (p<0.01, p<0.01, p<0.01), however, it decreased quadratically crypt depth in ileum on d 14 (p<0.05) and that in duodenum, jejunum and ileum on d 28 (p<0.01, p<0.05, p<0.05). In conclusion, these results indicated that chitosan could quadratically improve growth in weaned pigs, and the underlying mechanism may due to the increase of the serum GH concentration and improvement of the small intestines morphological structure.

Estimation of Measurement Uncertainty for the HPLC Analysis of Deoxynivalenol in Wheat (밀에서 HPLC에 의한 데옥시니발레놀 분석의 측정불확도 산정)

  • Ok, Hyun-Ee;Chang, Hyun-Joo;Ahn, Jang-Hyuk;Cho, Jae-Young;Chun, Hyang-Sook
    • Korean Journal of Food Science and Technology
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    • v.41 no.3
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    • pp.258-264
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    • 2009
  • The principal objective of this study was to estimate the measurement uncertainty associated with determination of deoxynivalenol (DON), a mycotoxin generated by Fusarium strain, in food. In service of this goal, wheat as a food matrix was analyzed via high performance liquid chromatography-ultraviolet (HPLC-UV) detection using an immunoaffinity column for clean-up. The uncertainty sources in the measurement process were identified by sample weight, final volume, and sample concentration in extraction volume with components including standard stock solution, working standard solution, 5 standard solutions, calibration curve, matrix, and instrument. The expanded uncertainty for DON at a concentration of 300 ${\mu}g/kg$ was estimated as 71.62 ${\mu}g/kg$ using a coverage factor of two, which provides a confidence level of approximately 95%. The most influential component in the uncertainty sources was the recovery of the wheat matrix, followed by the calibration curve. These results indicate that all efforts may be directed toward reducing the uncertainties of the recovery of the wheat matrix and the calibration curve to obtain a reliable HPLC-UV method for DON analysis in wheat.

Effects of photoperiod on nutrient digestibility, hair follicle activity and cashmere quality in Inner Mongolia white cashmere goats

  • Zhang, Chong Zhi;Sun, Hai Zhou;Li, Sheng Li;Sang, Dan;Zhang, Chun Hua;Jin, Lu;Antonini, Marco;Zhao, Cun Fa
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.4
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    • pp.541-547
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    • 2019
  • Objective: This study investigated the effects of photoperiod on nutrient digestibility, hair follicle (HF) activity and cashmere quality in Inner Mongolia white cashmere goats. Methods: Twenty-four female (non-pregnant) Inner Mongolia white cashmere goats aged 1 to 1.5 years old with similar live weights (mean, $20.36{\pm}2.63kg$) were randomly allocated into two groups: a natural daily photoperiod group (NDPP group:10 to 16 h light, n = 12) and a short daily photoperiod group (SDPP group: 7 h light:17 h dark, n = 12). All the goats were housed in individual pens and fed the same diets from May 15 to October 15, 2015. The digestibility of crude protein (CP), dry matter (DM), and neutral detergent fiber (NDF) were measured in different months, along with secondary hair follicle (SHF) activity, concentration of melatonin (MEL), and cashmere quality. Results: Although there was no significant difference in the live weights of goats between the SDPP and NDPP groups (p>0.05), the CP digestibility of goats in the SDPP group was significantly increased compared to the NDPP group in July, September, and October (p<0.05). For the DM and NDF digestibility of goats, a significant increase (p<0.05) was found during in September in the SDPP group. Furthermore, compared to the NDPP group, the SHF activity in July, the MEL concentration in July, and the cashmere fiber length and fiber weight in October were significantly increased in the SDPP group (p<0.05). Conclusion: The cashmere production of Inner Mongolia white cashmere goats was increased without obvious deleterious effects on the cashmere fibers in the SDPP group (metabolizable energy, 8.34 MJ/kg; CP, 11.16%; short daily photoperiod, 7 h light:17 h dark).