• Title/Summary/Keyword: Time-lag Effect

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Effect of Dietary Concentrate:forage Ratios and Undegraded Dietary Protein on Nitrogen Balance and Urinary Excretion of Purine Derivatives in Dorper×thin-tailed Han Crossbred Lambs

  • Ma, Tao;Deng, Kai-Dong;Tu, Yan;Jiang, Cheng-Gang;Zhang, Nai-Feng;Li, Yan-Ling;Si, Bing-Wen;Lou, Can;Diao, Qi-Yu
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.2
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    • pp.161-168
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    • 2014
  • This study aimed to investigate dietary concentrate:forage ratios (C:F) and undegraded dietary protein (UDP) on nitrogen balance and urinary excretion of purine derivatives (PD) in lambs. Four Dorper${\times}$thin-tailed Han crossbred castrated lambs with $62.3{\pm}1.9$ kg body weight at 10 months of age were randomly assigned to four dietary treatments in a $2{\times}2$ factorial arrangement of two levels of C:F (40:60 and 60:40) and two levels of UDP (35% and 50% of CP), according to a complete $4{\times}4$ Latin-square design. Each experimental period lasted for 19 d. After a 7-d adaptation period, lambs were moved into individual metabolism crates for 12 d including 7 d of adaption and 5 d of metabolism trial. During the metabolism trial, total urine was collected for 24 h and spot urine samples were also collected at different times. Urinary PD was measured using a colorimetric method and creatinine was measured using an automated analyzer. Intake of dry matter (DM) (p<0.01) and organic matter (OM) (p<0.01) increased as the level of UDP decreased. Fecal N was not affected by dietary treatment (p>0.05) while urinary N increased as the level of UDP decreased (p<0.05), but decreased as dietary C:F increased (p<0.05). Nitrogen retention increased as dietary C:F increased (p<0.05). As dietary C:F increased, urinary excretion of PD increased (p<0.05), but was not affected by dietary UDP (p>0.05) or interaction between dietary treatments (p>0.05). Daily excretion of creatinine was not affected by dietary treatments (p<0.05), with an average value of $0.334{\times}0.005$ mmol/kg $BW^{0.75}$. A linear correlation was found between total PD excretion and PDC index ($R^2$ = 0.93). Concentrations of creatinine and PDC index in spot urine were unaffected by sampling time (p>0.05) and a good correlation was found between the PDC index (average value of three times) of spot urine and daily excretion of PD ($R^2$ = 0.88). These results suggest that for animals fed ad libitum, the PDC index in spot urine is effective to predict daily excretion of PD. In order to improve the accuracy of the spot sampling technique, an appropriate lag phase between the time of feeding and sampling should be determined so that the sampling time can coincide with the peak concentration of PD in the urine.

The Impact of Changes in Market Shares among Retailing Types on the Price Index (소매업태간 시장점유율 변화가 물가에 미친 영향)

  • Moon, Youn-Hee;Choi, Sung-Ho;Choi, Ji-Ho
    • Journal of Distribution Research
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    • v.17 no.2
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    • pp.93-115
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    • 2012
  • This study empirically examines the impact of changes in market shares among retailing types on the price index. The retailing type is classified into 6 groups: department store, big mart, super market, convenient store, specialty merchant, and on-line store. The market shares of retailing types are calculated by the ratio of each retailing type monthly sales to total monthly retailing sales in which total retailing sales is the sum of each retailing type sales. We employed several price indices: consumer price index (CPI), CPI for living necessaries, and fresh food price index. In addition, this study used fundamental price indices based on 25 product families as well as 42 representative products. The empirical model also included several variables in order to control for the macroeconomic effects and those variables are the exchange rate, M1, an oil price, and the industrial production index. The data is monthly time-series data spanning over the period from January 2000 to December 2010. In order to test for the stability of data series, we conducted ADF test and PP test in which the model and length of lag were determined by the relevant previous literature and based on the AIC. The empirical results indicate that changes in market shares among retailing types have impacts on the price index. Table A shows that impacts differ as to which price index to use and which product families and products to use. For department store, it lowers the price of food and non-alcoholic beverages, home appliances, fresh food, fresh and vegetables, but it keeps the price high for fresh fruit. The big mart retailing type has a positive impact on the price of food, nut has a negative effect on clothing and foot wear, non-food, and fresh fruit. For super market, it has a positive impact on food and non-alcoholic beverages, fresh food, fresh shellfishes, but increases the price of CPI for living necessaries and non-food. The specialty merchant retailing type increases the price level of CPI for living necessaries and fresh fruit. For on-line store type, it keeps the price high for CPI for living necessaries and non-food as well as fresh fruit. For the analysis based on 25 product families shows that changes in market shares among retailing types also have different effects on the price index. Table B summarizes the different results. The 42 representative product level analysis is summerized in Table C and it indicates that changes in market shares among retailing types have different effects on the price index. The study offers the theoretical and practical implication to these findings and also suggests the direction for the further analysis.

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Structure and Variation of Tidal Flat Temperature in Gomso Bay, West Coast of Korea (서해안 곰소만 갯벌 온도의 구조 및 변화)

  • Lee, Sang-Ho;Cho, Yang-Ki;You, Kwang-Woo;Kim, Young-Gon;Choi, Hyun-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.10 no.1
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    • pp.100-112
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    • 2005
  • Soil temperature was measured from the surface to 40 cm depth at three stations with different heights in tidal flat of Gomso Bay, west coast of Korea, for one month in every season 2004 to examine the thermal structure and the variation. Mean temperature in surface layer was higher in summer and lower in winter than in lower layer, reflecting the seasonal variation of vertically propagating structure of temperature by heating and cooling from the tidal flat surface. Standard deviation of temperature decreased from the surface to lower layer. Periodic variations of solar radiation energy and tide mainly caused short term variation of soil temperature, which was also intermittently influenced by precipitation and wind. Time series analysis showed the power spectral energy peaks at the periods of 24, 12 and 8 hours, and the strongest peak appeared at 24 hour period. These peaks can be interpreted as temperature waves forced by variations of solar radiation, diurnal tide and interaction of both variations, respectively. EOF analysis showed that the first and the second modes resolved 96% of variation of vertical temperature structure. The first mode was interpreted as the heating antl cooling from tidal flat surface and the second mode as the effect of phase lag produced by temperature wave propagation in the soil. The phase of heat transfer by 24 hour period wave, analyzed by cross spectrum, showed that mean phase difference of the temperature wave increased almost linearly with the soil depth. The time lags by the phase difference from surface to 10, 20 and 40cm were 3.2,6.5 and 9.8 hours, respectively. Vertical thermal diffusivity of temperature wave of 24 hour period was estimated using one dimensional thermal diffusion model. Average diffusivity over the soil depths and seasons resulted in $0.70{\times}10^{-6}m^2/s$ at the middle station and $0.57{\times}10^{-6}m^2/s$ at the lowest station. The depth-averaged diffusivity was large in spring and small in summer and the seasonal mean diffusivity vertically increased from 2 cm to 10 cm and decreased from 10 cm to 40 cm. Thermal propagation speeds were estimated by $8.75{\times}10^{-4}cm/s,\;3.8{\times}10{-4}cm/s,\;and\;1.7{\times}10^{-4}cm/s$ from 2 cm to 10 cm, 20 cm and 40 cm, respectively, indicating the speed reduction with depth increasing from the surface.

Fermentation Properties of Young Radish Kimchi Prepared Using Young Radish Cultivated in the Soil Containing Sulfur and It's Inhibitory Effect on the Growth of AGS Human Gastric Adenocarcinoma Cells (유황처리 열무로 제조한 열무김치의 특성과 인체 위암세포의 성장억제효과)

  • Kong, Chang-Suk;Bak, Soon-Sun;Rhee, Sook-Hee;Rho, Chi-Woong;Kim, Nak-Ku;Choi, Keyng-Lag;Park, Kun-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.2
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    • pp.158-163
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    • 2006
  • Young radishes (YR, yeolmu in Korean) were cultivated in the soil with and without sulfur. YR-Control (without sulfur) was grown in the normal soil. YR were grown in the soil with $1,818\;g/m^3$ sulfur (YR-A) and $1,818\;g/m^3$ sulfur added lime mortar (YR-B) on it, respectively. Also, we prepared YR kimchis using YR-Control, YR-A and YR-B. The kimchis were fermented at $5^{\circ}C$ for 8 weeks. The growth inhibitory effects of AGS human gastric adenocarcinoma cells of the YR samples and kimchis were investigated. YR kimchis after $4\~5$ weeks at $5^{\circ}C$ showed higher acidity of $0.88\~1.20\%$ with pH $4.3\~4.5$ and the YR kimchis kept approximately pH 4.0 until 8 weeks. The kimchi A and B using YR-A and YR-B showed faster fermentation time, higher level of Leuconostoc sp. and lower level of Lactobacillus sp. during the fermentation, comparing to the control kimchi using YR-Control. Juices from YR-A and YR-B showed higher growth inhibitory effects of AGS human gastric adenocarcinoma cells than the juice from YR-Control at the same concentration. The growth inhibitory effect of YR-A was similar to that of the YR-B. The kimchi A and B juices also exhibited higher inhibitory effects $(74\%)$ on the growth of AGS human gastric adenocarcinoma cells than that of the control kimchi $(57\%)$ at the higher concentration of $20{\mu}L/assay$. Methanol extracts from the YR-kimchis also led to the similar results to the results of the juices. These results suggested that preparing of kimchi using differently cultivated YR especially in the soil with sulfur, which can help to synthesize sulfur-containing compounds, could increase the growth inhibitory effects of AGS human gastric adenocarcinoma cells.

Uptake of Butachlor by Rice Seedlings and Its Phytotoxic Action to the Physiological Activities (수도묘(水稻苗)의 Butachlor 흡수(吸收) 및 약해발생(藥害發生) 특성(特性)에 관한 생리적(生理的) 연구(硏究))

  • Chung, Bong-Jin;Kwon, Yong-Woong
    • Korean Journal of Weed Science
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    • v.1 no.1
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    • pp.57-68
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    • 1981
  • To clarify the mode of uptake of butachlor (2-chloro-2', 6'-diethyl-N-(butoxymethyl) acetanilide) by rice seedlings, its phytotoxic action to growth and physiological activities, studies were conducted with rice seedlings, at the 6th or 7th leaf-stage, which were treated with nutrient solution containing butachlor 0, 1.8, 3.6, 7.2, 10.8 or 14.4 ppm for 1, 2 or 4 days, in other case, the solutions were thereafter renewed with the untreated nutrient solution for further growth. Uptake of butachlor by rice seedlings increased linearly with increase of its concentration and duration of uptake. Butachlor inhibited root growth more than shoot growth, furthermore, the inhibitory effect on the shoot growth was greater in height than in weight or leafing rate. After 4 day-treatment, the rates of shoot growth in weight were delayed for 4 days. Butachlor inhibited water uptake rapidly and linearly with increase of its external concentration. The reduced uptake of water was followed by slow increase in the stomatal resistance of leaves. Upon completion of butachlor treatment, rate of water uptake was recovered rapidly, but the stomatal resistance with lag in time. Butachlor did not affect the uptake of cation such as ammonium, potassium and calcium, but inhibited substantially uptake of nitrate in proportion to its concentration. Especially, butachlor did not affect synthesis and degradation of nitrate reductase. In addition, butachlor has shown much greater binding to the lipidic substances from rice roots than the proteinous material. The primary mechanism of phytotoxic action of butachlor does not seem to be its effect on the protein synthesis, but great affinity to membranes. The inhibition of water uptake, and its subsequent closure of stomates is thought very important for reduced growth under mild phytotoxicity.

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The Effect of Ishige okamurae Extracts on Antioxidant Activity and Serum Lipid Content in Ovariectomized Rats (패 추출물의 항산화 활성 및 난소절제 흰쥐의 혈중 지질 함량 변화에 미치는 영향)

  • Kim, Bokyung;Kim, Mihyang
    • Journal of Life Science
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    • v.23 no.12
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    • pp.1501-1508
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    • 2013
  • This study investigated antioxidant activity and the lipid content of serum for the possible outcome of improving the activity of Ishige okamurae extracts in ovariectomized rats. The antioxidant effects of an Ishige okamurae water extract and an Ishige okamurae ethanol extract were measured by evaluating DPPH free radical scavenging activity and SOD-like activity. Fifty, seven-week old female Sprague Dawley rats were randomly assigned to five groups as follows: sham-operated rats (SHAM), ovariectomized rats (OVX-CON), ovariectomized rats that were treated with 17-beta-estradiol (200 ${\mu}g/kg/day$), and ovariectomized rats that were treated with Ishige okamurae extracts (50 mg/kg/day and 200 mg/kg/day, respectively). The diets were fed to the rats for seven weeks after ovariectomy. The antioxidant activities of the water and ethanol extracts of Ishige okamurae increased in a dose-dependent manner, and the ethanol extract was found to be higher than the water extract. Therefore, we examined the effect of an Ishige okamurae ethanol extract on total serum cholesterol, triglycerides, HDL-cholesterol, and LDL-cholesterol levels, and anti-platelet aggregation. The total-cholesterol and triglyceride content of the serum increased in the OVX-CON group compared to the SHAM group, but supplementation with the Ishige okamurae ethanol extract caused these factors to decrease. Notably, the serum LDL-cholesterol concentration in the supplemented 200 mg/kg/day Ishige okamurae ethanol extract group was significantly more reduced than it was in the OVX-CON group. In addition, the platelet aggregation ability was lower in the groups treated with Ishige okamurae than it was in the OVX-CON group. According to these results, the effects of Ishige okamurae extract on serum lipid content in ovariectomized rats were illuminated.

Inhibition of Escherichia coli 0157:H7 by Clove (Eugenia Caryophyllata Thumb) (Clove(Eugenia Caryophyllata Thumb)에 의한 Escherichia coli 0157:H7의 증식과 생존억제)

  • 박찬성
    • Korean journal of food and cookery science
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    • v.14 no.1
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    • pp.9-15
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    • 1998
  • The inhibitory effect of clove (Eugenia caryophyllata Thumb) on the growth of Escherichia coli 0157:H7 was determined. Tryptic soy broth (TSB) containing 0∼0.5% (w/v) of clove was inoculated with 10/sup/5∼10/sup/7 CFU/ml of E. coli and incubated at 5 different temperature (35, 5, -20, 50 and $55^{\circ}C$). The growth of E. coli was not inhibited at 0.1% clove and growth occured at 0.3% after a prolonged lag period while viable cells of E. coli decreased at 0.5% clove during storage at $35^{\circ}C$. During 32 days of refrigerated storage at $5^{\circ}C$, survivors of E. coli were decreased with the progress of time and increasing clove concentration. At the presence of 0.3 or 0.4% clove, bacterial cells were dead at the end of refrigerated storage. During frozen storage at -$20^{\circ}C$, survivors of E. coli at the presence of 0∼0.4% clove were decreased 2.9∼4.07 log cycles for 4 days of early period and then decreased 1.0∼2.1 log cycles through the frozen storage. There were small changes in populations of E. coli in TSB between different concentrations of clove during frozen storage. The D-values for E. coli at $50^{\circ}C$ were 105.26, 22.47, 13.76, 11.14 and 10.17 min at clove 0, 0.1, 0.2, 0.3, 0.4%, respectively. The D-values for E. coli at $55^{\circ}C$ were 10.75, 8.95, 7.40, 5.96 and 4.96 min at clove 0, 0.1, 0.2, 0.3, 0.4%, respectively. Antibacterial activity of clove against E. coli was more effective at $50^{\circ}C$ than at $55^{\circ}C$.

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Development of a Predictive Growth Model of Staphylococcus aureus and Shelf-life Estimation of Cooked Mung Bean Sprouts Served in School Foodservice Operations (학교급식에서 제공되는 숙주나물의 Staphylococcus aureus 성장예측모델 개발 및 섭취유효기간 설정)

  • Park, Hyoung-Su;Kim, Min-Young;Jeong, Hyun-Suk;Park, Ki-Hwan;Ryu, Kyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.11
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    • pp.1618-1624
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    • 2009
  • This study was conducted to estimate the shelf-life of cooked mung bean sprouts contaminated with Staphylococcus aureus according to storage temperatures after cooking in school foodservice operations. A predictive growth model of S. aureus in cooked mung bean sprouts prepared using a standard recipe was developed at 4 storage temperatures (5, 15, 25, and 35${^{\circ}C}$). To determine the effect of vinegar on the shelf-life of cooked mung bean sprouts, the growth of S. aureus in sprouts prepared using vinegar and the standard recipe were compared. The $R^2$ values of the specific growth rate (SGR) and lag time (LT) determined using the Gompertz model were greater than 0.90 at all temperatures except 5${^{\circ}C}$, which confirmed that it would be appropriate to use these parameters for a secondary model. The secondary model, which indicates changes in LT and SGR values according to storage temperatures, was calculated using response surface models. The compatibility of the developed model was confirmed by calculating $R^2$, Bf, Af and MSE values as statistic parameters. The $R^2$ values of LT and SGR were 0.94 or higher, and the MSE, Bf and Af values were 0.02 and 0.002, 0.97 and 1.03, and 1.31 and 1.10, respectively, with high statistical compatibility. The growth rate of S. aureus was higher when the standard recipe was used than when vinegar was used at all temperatures. Indeed, no growth of S. aureus was observed in mung bean sprouts prepared using vinegar. Based on the model developed, cooked mung bean sprouts prepared using the standard recipe for school foodservice should be stored at 10${^{\circ}C}$ or less. Additionally, sprouts stored at 25 or 35${^{\circ}C}$ should be consumed within 6 or 12 hours after cooking. Finally, the addition of vinegar will prevent the growth of S. aureus in cooked mung bean sprouts.

The Effect of Eisenia bicyclis Extracts on Antioxidant Activity and Serum Lipid Level in Ovariectomized Rats (대황 추출물의 in vitro 항산화 활성 및 난소를 절제한 흰쥐의 혈중 지질함량에 미치는 영향)

  • Park, Yong Soo;Kim, Mihyang
    • Journal of Life Science
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    • v.22 no.10
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    • pp.1407-1414
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    • 2012
  • Hormone replacement therapy (HRT) is an effective regimen that has been found to prevent these diseases in postmenopausal women. However, HRT is accompanied by an increased risk of unfavorable outcomes. This study was conducted to evaluate the effects of Eisenia Bicyclis extract on lipids in ovariectomized rats. Fifty 7-week-old female Sprague-Dawley rats were randomly assigned to four groups: sham-operated rats (SHAM), ovariectomized rats (OVX-CON), and ovariectomized rats that were treated with Eisenia bicyclis extracts. The extract-treated diets were fed to the rats for 6 weeks after operation. Antioxidant effects were measured by DPPH free radical scavenging activity. Antioxidant activity of the ethanol extract increased in a dose-dependent manner and was about 55.9% in a concentration of 100 ${\mu}g/ml$. We measured the total cholesterol content, triglyceride content, HDL-cholesterol content, LDL-cholesterol content, atherosclerotic index, cardiac risk factor in serum, and anti-platelet aggregation and blood rheology. The total cholesterol and triglyceride concentration in serum increased for the OVX-control group, but supplementation with the E. bicyclis extract caused these factors to decrease. Notably, the serum LDL-cholesterol concentration in the OVX-EB200 group was significantly lower than the OVX-CON group. In addition, the blood passage times in rats that received the E. bicyclis extract were more rapid than the times in the untreated group (OVX-CON). Microscopic evaluation revealed that whole blood passed more smoothly through the microchannels in rats in the E. bicyclis extract supplement groups. Our results clarified the effects of E. bicyclis extract on serum lipid content in ovariectomized rats, and consequently we expect positive effects from providing E. bicyclis extract to postmenopausal women with cardiovascular disease.