• Korean Journal of Poultry Science
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• v.28 no.1
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• pp.1-6
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• 2001

Two experiments were carried out to evaluate the effects of adding phytase on nutrient availability and serum Ca and P level and to determine the effects of phytase on laying performance and egg quality in laying hens. In Exp. 1, twenty four laying hens(1.9kg average body weight and 78.4% egg production) were allotted to four treatments. Treatments included 1) corn-soybean meal based-control diet and 2), 3) and 4) control diet with phytase 200, 400 and 600 unit/kg, respectively. There were no significant effects of treatments on dry matter and nitrogen digestibility(P〉0.05). Ash, Ca and P digestibility in layer fed diet with phytase were greater than those in layer fed control diet(P〈0.05). Laying hens fed diets with phytase 200 and 400 unit retained more Ca than those fed other treatments (P〈0.05). No statistical difference was found for Ca exsretion(P〉0.05). P retention was greater for laying hens fed diet phytase 600 unit than other treaments(P〈0.05). P level in serum was higher for laying hens fed diets with phytase 400 and 600 unit than for laying hens fed other treatments. In Exp. 2, three hundred, IAS Brown layer, 40-week-old, divided into two treatment groups(control vs phytase supplementation without inorganic phosphate in the diets) with five replications per treatment and 30 layers per replication were fed the diets for 6 weeks. Egg production, egg weight and eggshell breaking strength and thickness were not different significantly(P〉0.05). In conclusion, phytase supplementation can be used to increase P utilization and retention in laying hens. Also, phytase supplementation was effective to spare inorganic phosphate in laying hen diets without any adverse effects on production performances.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.4
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• pp.250-257
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• 2005

This study was conducted to investigate the effect of meteorological elements on the changes of inorganic nutrient contents in leaves of 'ruyu' and 'Nishimurawase' sweet persimmon during the growing season. The contents of N, P, K and Cu decreased in leaves of 'Fuyu' and 'Nishimurawase' sweet persimmon during vegetative growth, while Ca, Mg and Mn increased. The K content was higher in leaves of 'Fuyu' than in 'Nishimurawase' sweet persimmon. The P and Ca content was higher in 'Nishimurawase' leaves than in 'Fuyu' sweet persimmon. Mean temperature was positively correlated with content of P in leaves. Rainfall was positively correlated with the content of Ca in leaves, whereas it was negatively correlated with content of N and Cu in leaves. The duration of sunshine was positively correlated with N and Cu in leaves but negatively correlated with that of Ca, Mg, and Mn content.

• Animal cells and systems
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• v.7 no.4
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• pp.289-294
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• 2003

To quantify nutrient loading from emergent macrophytes through leaching in the littoral zones of Paldang Reservoir, we conducted incubation experiments using leaf litter of the emergent macrophyte, Zizaniz latifolia. To separate the leaching process from microbial decay, we used $HgCl_2$ to suppress microbial activity during the experiment. We measured electric conductivity, absorbance at 280nm, total nitrogen and dissolved inorganic nitrogen, total phosphorus and soluble reactive phosphorus, Na, K, Mg and Ca amounts in leaf litter and in water. In addition, we examined the effects of water temperature and ion concentrations of ambient water on the leaching process. A total of 6% of the initial ash-free dry mass of leaf litter was lost due to leaching during incubation (four days). Electric conductivity and A280 continued to increase and saturate during the incubation. To compare reaching rates of different nutrients, we fitted leaching dynamics with a hyperbolic saturation function [Y=AㆍX/(B+X)]. From these fittings, we found that ratios of leaching amounts to nutrient concentration in the litter were in the order of K > Na > Mg > P > Ca > N. Leaching from leaf litter of Z. latifolia was dependent on water temperature while it was not related with ion concentrations in the ambient water. Our results suggest that the leaching process of nutrients, especially phosphorus, from aquatic macrophytes provides considerable contribution to the eutrophication of the Paldang Reservoir ecosystem.

• Korean Journal of Microbiology
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• v.29 no.5
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• pp.329-338
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• 1991

From July 1985 to December 1986, 28 variables of phycal-chemical factors, bacteria and heterotrophic activity were investigated 17 times at 3 stations in the estuary of Naktong River and the influences of environmental factors to bacterial population and heterotrophic activity were analyzed through multiple regression. The results of multiple regression were as follows. At station 1, total bacteria and heterotrophic bacteria(Z-25) could explain 57% of the variation of maximum uptake velocity for glucose and 54% of turnover time for glucose was explained by total coliform bacteria and MBOD, Sixty four percent of the variation of Kt+SN was accounted for salinity, MBOD-N and inorganic phosphate. Turnover rate for acetate was also accounted for the change of MBOD-P by 56%. At station 2 maximum uptake velocity for glucose depends on MBOD-N by 81%; turnover time on bacteria by 50%; Kt+Sn on avilable nutrient by 61%. More than 50% of maximum uptake velocity and turnover time for glucose were influenced by bacteria and that of Kt+Sn by the change of nutrient in the surface water of station 3. In the bottom water of station 3, the change of maximumuptake velocity, turnover time and Kt+Sn for glucose was controlled by total bacteria and available nutrient, bacteria, the change of nutrient salts respectively. On the whole, more than 50% of maximum uptake velocity and turnover time for glucose could be due to the change in the number of bacetria and the value of Kt+Sn was affected by the change of nutrient salts. Turnover rate for acetate was controlled by available phosphate at station 1 and by bacteria at station 2 and 3, which showed a distinct difference between the environmental factors which govern the rate of glucose and acetate uptake in the Naktong esturine ecosystem. And bacterial communities were controlled by available nutrients at station 1, by nutrient salts and salinity at station 2 and in the surface water of station 3 and by salinity in the bottom water of station 3.

• Journal of environmental and Sanitary engineering
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• v.10 no.3
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• pp.56-66
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• 1995

To investigate environmental impacts of inland fish- farms on the water quality of a stream, environmental parameters including physical, chemical and biological factorswere estimated at trount- farm in 1994. Influences( F-1) were polluted as passing through fish tank( F-2) and settle pond( F-3), so organic and inorganic nutrient concentrations became very high in effluents( F-4). BOD$_{5}$, Chl. a, Nitrite and heterotrophic bacterial numbers in the junction site(5-2) of F-4 and S-1( upstream) were highest among the stream sites. BOD$_{5}$ was proved to a good parameter of organic pollution, and nitrite of Inorganic nutrients in the fishery and it's affected stream, The high concentration of BOD$_{5}$ and Chl. a in S-2 were decreased in downstream(5-3, 5-4). It seems that this results are due to dilution or sedimentation effect. This supposition requires further testing about the sediment of stream. The results of this paper demonstrate that fish farming can deteriorate water quality of a stream by changing environmental factors.

• 보존과학연구
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• s.26
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• pp.5-25
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• 2005

A consideration number of investigation have begun to elucidate the essential role biological agents play in the deterioration of stone. What is becoming clear is that many factors affect the durability of stone. Physical, chemical, and biological agentsact in co-association, ranging from synergistic to antagonistic, to deteriorate stone. Biodeterioration has usually been considered to be a degradation process following the initial deterioration effects of inorganic agents, especially objects of cultural value such as pagoda, stature of Buddha etc. These agents were thought to condition stone surfaces for microbial contamination due to structural changes and enrichment of inorganic organic nutrient substrates. This report concentrates on the action of biodeteriogens from bacteria to algae and higher plants. Preventive and remedial methods are surveyed, as are a selection of chemical treatments.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.817-825
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• 1998

A three-dimensional ecosystem model is applied to the Suyoung Bay, located at the southeastern part of Korea, to study of the material distribution in the time scale of several tens days. The model has included of the DIN(Dissolved Inorganic Nitrogen), DIP(Dissolved Inorganic Phosphate), phytoplankton, zooplankton and detritus, and also was coupled with the physical processes. The spatial distribution of chlorophyll-a and primary productivity in the model is determined by the physical and chemical-biological parameters. The horizontal distributions of the DIN, DIP and chlorophyll-a are decreased from the coast to the off-shore, though the nutrients show some more complicated pattern than the chlorophyll-a. The nutrient contents in the off-shore are low, and thus a relatively low productivity(chlorophyll-a) are presented. On the whole, the distribution of the results of model are smoother than the observed ones and some small scale variation in the observed data cannot be reproduced by the model due to the resolution limits of model. However, the basic pattern and the quantitavities has been reproduced by the model well.

• Korean Journal of Pharmacognosy
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• v.3 no.2
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• pp.65-72
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• 1972

Tissues of $Panax\;Schinseng\;N_{EES}\;root$ were cultured on the synthetic agar media to investigate the nutrient efficiency on the callus induction and organ formation. The differentiation pattern of the callus mass and the structure of the induced organ (root) were observed internally. On White's medium, callus formation needed the supplement of 2,4-D (5mg/l) and kinetin (1.0mg/l), and on MS medium the root induction NAA (0.2mg/l) and kinetin (0.1mg/l). In order to investigate the effect of inorganic components on callus formation, the inorganic part of White' medium was substituted with those of Heller, Murashige Skoog, and Earle. As the result culture Earle's was most effective. On the other hand, the roots were induced from the meristem in the deep region of callus mass. Since this meristem is similar to the pericambium of tap root, they are the same on the pattern of morphogenesis.

• Journal of the korean society of oceanography
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• v.39 no.1
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• pp.14-19
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• 2004

Difference of Dissolved Inorganic Phosphorus (DIP), Dissolved Inorganic Nitrogen (DIN) and Dissolved Silicate (DSi) budgets in the Bohai Sea between 1982 and 1992 related the decrease of the Yellow River discharge is discussed on the basis of observed data. The estuarine circulation in the Bohai Sea had been weakened from 1982 to 1992 due to the decrease of the Yellow River discharge and the average residence time of fresh water had become longer. DIN concentration increased but DIP and DSi concentrations decreased from 1982 to 1992 in the Bohai Sea. Primary production was regulated mainly by water temperature and DIN concentration in 1982 but it was regulated mainly by DIP concentration in 1992. Primary production was larger than decomposition plus bottom release and nitrogen fixation was larger than denitrification in 1982. However, decomposition plus bottom release was larger than primary production and denitrification was larger than nitrogen fixation in 1992 in the Bohai Sea.

• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.284-295
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• 1990

Dietary levels of 0%, 0225%, 0.45% inorganic phosphorus in the form of tricalcium phosphate were included in two different experimental diets, which contains 40% of wheat bran with or without extrusion. It is to examine the effects of extruded wheat bran containing different Bevels of inorganic phosphorus on the performance of broiler chicks, including the nutrient availabilities, compared with that of the diet containing non－extruded wheat bran. The results are as follows； 1. Regardless dietary levels of inorganic phosphorus, the weight gain in general was higher for the groups fed non－extruded wheat bran but little significance was seen between the groups of extruded and the non－extruded. However, the effect of dietary inclusion of inorganic phosphorus on the weight gain was evident and the gain was higher in the groups receiving the higher levies of inorgainc phosphorus but failed to observe the significant difference between the added groups of 0.225% and 0.45% of inorganic phosphorus, suggesting that a considerable amount of phytin phosphorus in wheat bran is available to meet the requirement. 2. For the feed intake, there was a tendency for the groups fed extruded wheat bran consuming more feed, compared with that of the non－extruded but little significance was observed. This was also true between the groups of receiving 0.225% and 0.45% inorganic phosphorus t The feed efficiency was improved by the addition of inorgainc phosphorus, but failed to observe the significance between the added groups. 4. The dry matter digestibility was improved in proportion to increasing the levels of inorganic phosphorus for the both groups of extruded and the non－extruded This indicates that addition of extruded wheat bran has little effects on improving the digestibility. 5. Within the added groups of 0.225% and 0.45% inorganic phosphorus, the protein digestibility was increased with including the extruded wheat bran in the diet However, the effect on body weight gain was not evident. 6. The calcium and phosphorus content of tibia was shown the tendency of increasing with increasing the dietary levels of inorganic phosphorus but close correlation with dietary levels of inorganic phosphorus was not noted in tibia contents of calcium and phosphorus.