• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.21-31
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• 2006

The objectives of this study were to analyze trends of temporal water quality and trophic state in Andong and Imha reservoirs using chemical dataset during 1993 ${\sim}$ 2004, obtained from the Ministry of Environment, Korea. According to long-term limnological analyses, Suspended solids (SS) in Imha Reservoir were 2 ${\sim}$ 8 fold2 greater, than those in SS of Andong Reservoir, and the high solids increased total phosphorus (TP) and biological oxygen demand ($BOD_5$) and decreased the transparency, measured as Secchi depth (SD). Chlorophyll-a (CHL-a) increased little or decreased slightly in the both reservoirs during the high solids, resulting in reduced yields of CHL-a : TP ratios. The deviation analysis of Trophic State Index (TSI) in Imha Reservoir showed that about 70% of TSI (CHL-a)-TSI (SD) and TSI (CHL-a)-TSI(TP) values were less than zero and the lowest values were-60, indicating that influence of inorganic solids (or non-volatile solids) on phytoplankton growth was evident in Imha Reservoir and the impact was greater than that of Andong Reservoir. Inorganic solids in Imha Reservoir resulted in light limitation on phytoplankton growth and thus contributed variations in the relations among three parameters of trophic state index. Especially, seasonal data analysis of nutrients in both reservoirs showed that during the postmonsoon, mean TP concentration was Imha Reservoir greater in than that in Andong Reservoir. The higher TP concentrantion was mainly attributed to increases of inorganic solids from soil erosions and nonpoint source inputs within the watershed. The high inorganic turbidity in Imha Reservoir should be reduced for the conservation of water quality for, especially a tap water supply.

• Korean Journal of Poultry Science
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• v.36 no.3
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• pp.257-264
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• 2009

This work was conducted to investigate the effects of phytase on N and P excretion of laying hens excreta. Three hundred sixty ISA Brown layers were selected to investigate excreta excretion for 65 weeks and to investigate the effect of phytase on total excretion and N and P excretion of layers from 55 weeks. The experimental diets were fed the starter (0~5 wk), grower (5~12 wk), developer (12~16 wk), prelay diets (16 wk~first egg), layer diets for starting period (first egg~32 wk), middle (32~45 wk), finishing diets (45~55 wk, 55 wk~). Thirty ISA Brown layers were selected to investigate the effect of phytase supplementation on total N and P excretion of layers at 55 weeks and assigned randomly to 3 treatments groups (10 birds/treatment) and phytase was added to basal diets at 300 and 600 FTU/kg. Average body weight, feed intake, water intake, and excreta excretion were 1,622, 105.7, 187.2 and 124.7 g/bird/day, respectively. Excreta of birds fed phytase were DM (33.2, 31.2, 30.5 g/day), N (0.46, 0.42, 0.40 g/day) and P (0.51, 0.49, 0.48 g/day) and reduced as dietary phytase increased, Finally, dietary phyase can reduce the N and P excretion, but the amount of excreta was not different depending from the phytase addition in layers. This work investigated the N and P excretion of laying hens excreta and were considered that dietary phytase can reduce the N and P excretion for short period.

• Korean Journal of Remote Sensing
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• v.30 no.4
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• pp.481-491
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• 2014

Blue-ice area is a glacial ice field in ice sheet, ice shelf and glaciers where snow ablation and sublimation is larger than snowfall. As the blue-ice area has large influences on the meteorite concentration mechanism and ice mass balance, it is required to quantify the concentration of blue-ice. We analyzed spectral reflectance characteristics of blue-ice, snow and cloud by using MODIS images obtained over blue-ice areas in McMurdo Dry Valleys, East Antarctica, from 2007 to 2012. We then developed Normalized Difference Blue-ice Index (NDBI) algorithm which quantifies the concentration of blue-ice. Snow and cloud have a high reflectance in visible and near-infrared (NIR) bands. Reflectance of blue-ice is high in blue band, while that lowers in the NIR band. NDBI is calculated by dividing the difference of reflectance in the blue and NIR bands by the sum of reflectances in the two bands so that NDBI = (Blue-NIR)/(Blue + NIR). NDBI calculated from the MODIS images showed that the blue-ice areas have values ranging from 0.2 to 0.5, depending on the exposure and concentration of blue-ice. It is obviously different from that of snow and cloud that has values less than 0.2 or rocks with negative values. The change of NDBI values in the blue-ice area has higher correlation with snow depth ($R^2=0.699$) than wind speed ($R^2=0.012$) or air temperature ($R^2=0.278$), all measured at a meteorological station installed in McMurdo Dry Valleys. As the snow depth increased, the NDBI value decreased, which suggests that snow depth can be estimated from NDBI values over blue-ice areas. The NDBI algorithm developed in this study will be useful for various polar research fields such as meteorite exploration, analysis of ice mass balance as well as the snow depth estimation.

• Journal of Animal Science and Technology
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• v.52 no.4
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• pp.297-304
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• 2010

This study was conducted to investigate the effects of dietary quercetin on feed utilization, blood parameters, and meat quality of Korean native goats. Totally sixteen Korean native goats, 15 kg of average BW aged at 7 months, were employed in the experiment with eight replicates per treatment. One group was fed quercetin at 200 mg/kg level and the other group was fed none as control for 15 days. Dietary inclusion of quercetin did not affect feed intake, water intake, and the amount of urine and feces. Digestibilities of crude fat, NDF, and ADF for 5 days were not affected, but digestibility of crude protein was increased by the dietary inclusion of qurecetin (P<0.05). Quercetin increased rumen total VFA, propionate, and butyrate significantly (P<0.05). Acetate/propionate ratio (A/P) in the quercetin treated group was significantly higher than control. 2,2-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) ($ABTS^+$) reducing activity of the loin from goat fed quercetin was higher than that of control. Sensory analysis conducted at 24 hr post mortem revealed that color, texture, and overall acceptability of the loin from goat fed quercetin were significantly preferred to that of control. Feeding quercetin did not influence pH, water holding capacity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, TBARS value, and fatty acid composition of the loin significantly. In conclusion, the dietary inclusion of quercetin increased the digestibility of crude protein, rumen total VFA, propionate, butyrate, and A/P ratio. In addition the higher color and texture preference and ABTS+reducing activity of loin indicating some beneficial effect on enhancement of meat qualityin goats.

• Journal of Animal Science and Technology
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• v.52 no.4
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• pp.319-328
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• 2010

This work was carried out to investigate the quantity of excreta and its composition in crossbred pigs (Yorkshire ${\times}$ Landrace ${\times}$ Duroc) at different stages of growth. Twelve young piglets (average BW weight of $19.0{\pm}0.33kg$) were used in this study. Pigs were divided into four phases during growing time and two phases during finishing time. The average excreta production for growing pig was 3.46 kg/head/day (feces: 1.07 kg, urine: 2.39 kg). The average moisture contents of feces and urine were 70.54% and 97.39%, respectively. Contents of Calcium, Magnesium, Copper, Plumbum, and Arsenic were 1.00%, 0.26%, 10.47 mg/kg, 2.43 mg/kg, and 1.02 mg/kg, respectively. The concentration of the water pollutants like Biochemical Oxygen Demand ($BOD_5$), Chemical Oxygen Demand (COD), Suspended Solid (SS), Total Nitrogen (TN) and Total Phosphorus (TP), excreted from pig were 96335, 61073, 207466, 8104 and 4209 mg/L in feces and 7364, 7149, 2715, 10110 and 613 mg/L in urine at the end of test, respectively. The daily loading amount of water pollutants ($BOD_5$, COD, SS, TN, and TP, respectively) in pig excreta were 102.1, 61.8, 221.6, 8.7, and 3.9 g/head/day in feces, and 19.3, 16.7, 8.0, 22.2, and 1.3 g/head/day in urine, respectively. The Nitrogen, $P_2O_5$, and $K_2O$ contents in the excreta of pigs were 0.96, 0.83 and 0.42% in feces, and 0.80, 0.09 and 0.53% in urine, respectively. Finally, this work was suggested to give basic information to swine farms.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.264-270
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• 2008

Phytic acid(PA) (Inositol hexaphosphate, $IP_6$) is a naturally occurring polyphosphorylated carbohydrate that is present in substantial amounts in almost all plants and mammalian cells. Recently PA has received much attention for its role in anticancer activity. In the present study, the preventive effects of PA on colon carcinogenesis were investigated. Six-week old Fisher 344 male rats were fed a AIN-93G purified diet and PA(0.5% or 2% PA in water) for 8 weeks. The animals received two ($1^{st}\;and\;2^{nd}$ week) injections of azoxymethane(AOM, 15 mg/kg b.w.) to induce colonic aberrant crypt foci(ACF). After sacrifice, the total numbers of aberrant crypts(AC) and ACF in colonic mucosa were examined after staining with methylene blue. Blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. AOM induced the total numbers of $142.3{\pm}22.3$ ACF/colon and $336.6{\pm}55.1$ AC/colon. PA at the doses of 0.5 and 2% decreased the numbers of ACF and AC/colon in a dose-dependent manner. The numbers of ACF/colon and AC/colon by PA at the dose of 0.5% were $124.4{\pm}28.5\;and\;302.7{\pm}67.3$, respectively. PA at the dose of 2% significantly decreased the ACF and AC numbers to $109{\pm}18.1\;and\;254.8{\pm}50.6$, respectively(p<0.01). Especially, 2% PA significantly reduced the number of large ACF(${\geq}4$ AC/ACF) from $26.8{\pm}6.2$ ACF/colon to $15{\pm}6.7$ ACF/colon(p<0.01). Although some parameters in blood counts and serum chemistry were changed compared with the control, no specific toxicity was found. These findings suggest that phytic acid can be a chemopreventive agent for colon carcinogenesis resulting from inhibition of the development of ACF in the F344 rat.

• Journal of Radiation Protection and Research
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• v.27 no.1
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• pp.37-49
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• 2002

The accuracy of radiation dose delivery to target volume is one of the most important factors for good local control and less treatment complication. In vivo dosimetry is an essential QA procedure to confirm the radiation dose delivered to the patients. Transmission dose measurement is a useful method of in vivo dosimetry and it's advantages are non-invasiveness, simplicity and no additional efforts needed for dosimetry. In our department, in vivo dosimetry system using measurement of transmission dose was manufactured and algorithms for estimation of transmission dose were developed and tested with phantom in various conditions successfully. This system was applied in clinic to test stability, reproducibility and applicability to daily treatment and the accuracy of the algorithm. Transmission dose measurement was performed over three weeks. To test the reproducibility of this system, X-tay output was measured before daily treatment and then every hour during treatment time in reference condition(field size; $10 cm{\times} 10 cm$, 100 MU). Data of 11 patients whose pelvis were treated more than three times were analyzed. The reproducibility of the dosimetry system was acceptable with variations of measurement during each day and over 3 week period within ${\pm}2.0%$. On anterior- posterior and posterior fields, mean errors were between -5.20% and +2.20% without bone correction and between -0.62% and +3.32% with bone correction. On right and left lateral fields, mean errors were between -10.80% and +3.46% without bone correction and between -0.55% and +3.50% with bone correction. As the results, we could confirm the reproducibility and stability of our dosimetry system and its applicability in daily radiation treatment. We could also find that inhomogeneity correction for bone is essential and the estimated transmission doses are relatively accurate.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.567-570
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• 2006

This study was carried out to investigate the effect of antihypertensive peptides originating from marine proteins on ACE inhibitory activity and systolic blood pressure in spontaneously hypertensive rats (SHR). Sixteen male SHR (SHR/NCrj) weighing approximately 270 g were randomly divided into few experimental groups based on diet: C (control), A (anchovy), P (pollack) and M (mackerel). The final body weights of P and M groups were higher, than those of C and A groups, but difference was not significant. Average reference blood pressure (RBP) was 224 mmHg at 12 weeks old. Compared with RBP, final systolic blood pressure of the marine peptide oops after 28 days of feeding with anchovy, pollack and mackerel fractions by gavage was decreased by 9.0% (A), 10.2% (P) and 14.3% (M), respectively, but was not different in C. Especially, final blood pressure of M was lower by 32 mmHg than RBP. These results suggested that peptide originated from mackerel hydrolysate was considered to have an antihypertensive fraction as effective lowering of blood pressure in SHR.

• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.252-263
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• 1984

This study was conducted to find out the effect of thyroid function on Hypophysis, and serum FSH and LH concentrations in female rats. One hundred and forty-four female rats (wistar-imamichi albino rats) of 25 days old were divided into 4 groups; thyroidectomy (Thx.) propylthiouracil (PTU), thyroxine (Thyro.) and control (Cont.) groups. Thirty-six heads of rats were arranged to each group. The thyroid glands of the thyroidectomized groups were removed by surgery. The PTU treated groups were drunk the propylthiouracil solution of 0.05% and the thyroxine treated groups were administered subcutaneously with $30{\mu}g$ per 100 g body weight on 3 days intervals. Every 6 heads of rats in each group were sacrificed at 1, 2, 3, 4, 5, and 6 weeks after treatment with time elapse for investigating the weights and histological changes of hypophysis. The results obtained were as follows : 1. The weights of hypophysis at all treated groups were higher than control group, but significantly increased from 3 to 5 weeks. The significance was not recognized between Thyro. and control groups, and Thx. and PTU groups. 2. In the histological changes of hypophysis, eosinophils atrophied from 4 weeks after treatment in Thx. and PTU groups, and basophils showed hypertrophy and hyperplasia from 2 weeks after treatment and thereafter this tendency was more serious showing vacuolization from 4 weeks after treatment. In Thyro. treated group, eosinophils showed slight hypertrophy and basophils atrophied from 5 weeks after treatment but the group showed the similar histological changes in comparison with the control group. 3. The changes of the concentrations of serum FSH at all observation times were significantly recognized among all observation groups. The concentrations in True and PTU groups were significantly lower than those in control group, but those in Thyro. group were significantly higher than those in control group. 4. The changes of the concentrations of serum LH in all treated groups were significantly lower than those in control group. The significance was not recognized between True and PTU group, and Thyro. and control groups.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.540-545
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• 1982

An energy metabolism study was conducted with two commercial strains of meat-type chickens, Hubbard and Cobb, and two egg strains, Hy Line and Korean-bred Hanhyup 325. The heat production of growing chickens from each strain were measured by the use of an open-circuit gravimetric respiration calorimeter. The data obtained from this study were summarized as fallows. 1. The average body weight of 9-wk-old Hubbard broilers reared in battery cages was 2,570g/bird. The average body weights of 9-wk-old Hy Line chicks and Hanhyup 325 were 777 and 748g/bird, respectively. 2. At 3 weeks of age, the Hubbard broiler chicks consumed two times the feed consumed by Hy Line chicks (54.6g VS. 26.7g/bird/day). These values increased to 151g and 57.2g/bird/day, respectively, at 8 weeks of age, indicating that the difference in feed intake between meat and egg-type chicks tends to increase as they grow older. In terms of water consumption, the 5-wk-old Hubbard broiler chicks drank $226m{\ell}/bird/day$ as compared with $58m{\ell}$ by Hy Line chicks. These values increased to 282 and $70m{\ell}$, respectively, at 8 weeks of age. 3. The excreta outputs of Hubbard broilers and Hy Line chicks were 18.7 and 6.1g DM/bird/day at 4 weeks of age, and 41.5 and 10.0g DM/bird/day at 8 weeks of age, respectively. 4. The energy metabolizability of broiler chicks were 75.4~77.1% compared to 75.0~83.5% by egg-type chicks. 5. The respiratory quotient (RQ) was between 0.78 and 0.97. There seems to be no difference in RQ between meat and egg-type chicks. The RQ tended to decrease when feed intake was low and vice versa. 6. Both meat and egg-type chicks produced $83.1{\sim}123.1Kcal/kg^{\frac{3}{4}}B.W./day$. The considerably low value of $83Kcal/kg^{\frac{3}{4}}B.W./day$ was obtained when the chicks were off the feed under the stressful conditions. The high value of 123.1Kcal was obtained when the chicken chamber temperature rose to $27{\sim}34^{\circ}C$.