• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.341-350
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• 2009

The research work was carried out to study the pathogenesis covering the clinical signs, gross and histopathological lesions in different organs, and reisolation and identification of the organisms after experimental infection with the local isolate of Salmonella enterica serovar. enterica subspecies (S.) Pullorum at different time interval of the experiment during the period February 2006 to December 2006. One hundred pullets (seronegative to S. Pullorum of 12 weeks age were purchased and divided into 5 (A, B, C, D and E) groups and each group consisted of 20 birds. Four groups (A, B, C and D) were infected orally with a dose of $10^6\;CFU$, $10^7\;CFU$, $2{\times}10^7\;CFU$, $10^8\;CFU$ of S. Pullorum, respectively, and one group (E) was treated as uninfected control. The used methods were necropsy and histopathology, culture of bacteria, staining and biochemical test of Salmonella. Five birds from each group were randomly selected and sacrificed $1^{st}$ week, $2^{nd}$, $3^{rd}$ and $4^{th}$ weeks of post infection (PI). From all the groups, the bacteriological samples (crop, liver, lung, heart, spleen, bile duodenum, ceca and blood) were collected with pre enriched in buffered peptone water in sterile poly bags. Liver, lungs, heart, spleen, intestine, etc. were collected in 10% buffered-formalin for histopathological examination. No clinical signs, gross and histopathological lesions were found in control group and no S. Pullorum was reisolated. Clinical sign of experimentally infected with S. Pullorum in pullets were loss of appetite (100%), slight depression (75%), ruffled feathers (85%), diarrhea (60%) and loss of weight (100%) in chickens. The feed intake and body weight at different weeks after PI differed significantly (p<0.01) among the groups. Grossly, the highest recorded lesion was button-like ulcer in the ceca (80%) and the lowest was white nodules in lungs (1.25%). S. Pullorum were reisolated from crop (91.25%), liver (91.25%), lung (83.75%), heart (71.25%), spleen (87.75%), bile (33.25%), duodenum (92.50%), ceca (97.50%) and from different group of infection (61.25%). The highest microscopic findings were intestinal and cecal mucosa and submucosa exhibited infiltration of mononuclear cells and congestion (96.25%), and the lowest finding was nodule formation in the lungs (3.75%). The pattern of the disease production by local isolate of S. Pullorum in Bangladesh is almost similar with other isolates in different countries.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.120-132
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• 1993

A continuous hollow fiber membrane reactor(CHFMR) was developed and optimized for the production of yellowfin sole(Limanda aspera) skin gelatin hydrolysates using trypsin. The results were summerized as follows: The $K_m$ value of the CHFMR was 2.4 times higher than that of the batch reactor, indicating reduced enzyme affinity for the substrate. The $K_2$ value of the CHFMR was 8.5 times lower than that of the batch process, showing a significant reduction in trypsin activity in the CHFMR. The optimum operating conditions for the CHFMR process were $55^{\circ}C$, pH 9.0, flux 7.79 ml/min, residence time 77min, and trypsin to substrate ratio, 0.01(w/w) After operating for 60min under the above conditions, $79\%$ of the total amount of initial gelatin was hydrolysed. Enzyme leakage was observed through the 10,000 MWCO membrane after the 20min of reactor operation, while none occurred after 5hr. Total enzyme leakage was about $12.95\%$ at $55^{\circ}C$ for 5hrs. However, there was no apparent correlation between enzyme leakage and substrate hydrolysis. The membrane has a significant effect on trypsin activity loss for 60min of the CHFMR operation. The CHFMR operating with the membrane lost $34\%$ of the initial activity versus a $23\%$ loss of activity after 3hr in the continuous reactor lacking the hollow fiber membrane. The measurement of fouling property showed that relative flux reduction was $91\%$ and flux recover rate was $92\%$ at $10\%$ substrate solution. The productivity(378.85mg product/mg enzyme) of the CHFMR was more than 4 times higher than that of the batch reactor at $55^{\circ}C$.

• Journal of Hydrogen and New Energy
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• v.7 no.1
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• pp.81-92
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• 1996

The Ar/Ar-$H_2$ plasma method was applied to reduce oxides and refine metals of V, Ta and B. In addition, the high temperature chemical reaction in Ar plasma and of the refining reaction in the Ar-(20%)$H_2$ plasma were analyzed. The crude V of 96wt% purity was obtained at the ratio of $C/V_{2}O_{5}=4.50$ by the Ar plasma reduction grade and the maximum reduction was obtained at $C/V_{2}O_{5}=4.50$ due to the $O_{2}$ loss from the thermal decomposition of vanadium oxide. In the Ar-(20%)$H_2$ plasma refining, the metallic V of 99.2wt% was produced at the ratio of $C/V_{2}O_{5}=4.40$. It was considered that a main refining reaction resulted from the chemical reaction between the residual carbon and residual oxygen. The metallic Ta of 99.8wt% was obtained at the ratio of $C/Ta_{2}O_{5}=5.10$ in a Ar plasma reduction and the Oz loss from the thermal decomposition of tantalum pentoxide did not take place. The deoxidation reaction was more significant than the decarburization reaction in the Ar-(20%)$H_2$ plasma refining and the metallic Ta of 99.9wt% was produced within the range of $C/Ta_{2}O_{5}$ ratio of 4.50 to 5.10. The Vickers hardness of Ta in the above mentioned range was about 220Hv due to the decrease in a residual oxygen by the deoxidation reaction. On the other hand, C is no suitable agent for the reduction of $B_{2}O_{3}$ by the Ar and Ar-$H_2$ plasma. But Fe-B-Si alloy was produced with the reduction of $B_{2}O_{3}$ in the melt when Fe, C, $B_{2}O_{3}$, and ferroboron mixtures were melted by the high frequency induction melting.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.377-386
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• 2003

A study was conducted to evaluate seasonal variations in chemical composition of food waste (FW) and its feeding effects on growth performance and pork quality in finishing pigs. FW was collected for 1 year (6 times a month) to establish a database for use of FW as a feed ingredient. For a feeding trial (8 weeks), a total of 117 pigs ${\times}$D; 54.80$\pm$4.60kg) were used to evaluate the processing effects of FW. Treatments were: Control (a corn-soybean meal diet without FW), simple dried FW (SD) and vacuum fermented FW (VF). The gross energy, crude protein, crude fat, ash, calcium and phosphorus in FW (DM, average of 4 seasons) were 5,111kcal/kg, 22.92%, 14.31%, 15.48%, 2.7% and 1.05%, respectively. Among seasons, the energy and crude protein contents were the highest (p<0.05) in winter and summer, respectively. In lactic acid bacterial counts, there was no difference between SD and VF. Pigs fed the control diet grew faster (p<0.05) than those fed diets containing food wastes, but not feed conversion ratio. There were no differences in production traits between SD and VF. No differences were also found in dressing percentage, backfat thickness, and pork quality (color, drip loss and TBARS) among treatments. The feed cost (￦/kg body weight) was lower in pigs fed FW than those fed a control diet. In conclusion, a pelleted diet containing food waste less than 20% would reduce feed cost in finishing pigs. However, it seems that a vacuum fermentation of food waste is not necessary for diet processing.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.309-316
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• 1988

Several experiments were conducted to investigate the achene viability and growth characteristics of Eclipta prostrata (L.) L. No dormancy and no after-ripening requirement were found for E. prostrata achenes. When achenes were stored at room temperature, germination did not decrease with up to 5 months storage. Large differences in loss of viability of E. prostrata achenes occurred when different dehydration methods were used. Immediate dehydration resulted in high viability, but slow dehydration resulted in severe loss of viability. Achene viability at shallow burial depths (5 and 10 cm deep) was lower under upland soil conditions than under lowland soil conditions. Seedling growth was greatly reduced when flooding to a depth of 10 cm occurred at or before the 4-leaf stage. Flooding after the 4-leaf stage stimulated stem elongation. Branching started from the second week and usually terminated at the tenth week. Leaf size was determined by the branch which are related to the assimilate supply. Flowering of E. prostrata started during the fifth week after emergence, and mature achenes were produced from the sixth week. Ten to 14 days were needed for the achenes to mature. About 14,000 achenes were produced on each plant. Achene production per week increased from the sixth week to the tenth week and thereafter it declined. The average number of achenes per inflorescence decreased with delay in flowering.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.87-94
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• 2007

This study was carried out to know the effect of the oriental medicinal plants byproduct containing vitamin E and 0.1% antibiotics (T1) and the oriental medicinal plants byproduct containing vitamin E and the replacing antibiotics by 0.03% herb extracts (T2) and 0.1% aminolevulinic acid (T3) on production performance of finishing hog and its meat qualities. There were no significant differences in the daily weight gain, feed intake, and feed conversion rate values between all treatment groups. However, the T2 group tends to have a higher daily weight gain (g/day) than the other groups (p>0.05). The T2 group showed lower total-cholesterol and LDL-cholesterol contents (114.71 and 68.09 mg/dl, respectively) than the control in the blood serum (p<0.001), and all the treated groups of oriental medicinal plants byproduct and vitamin E increased HDL-cholesterol and decreased LDL-cholesterol contents in the blood serum. Content of vitamin E in muscles from the group T1, T2 and T3 (2.11, 2.21 and 2.18 mg $kg^{-1}$, respectively) showed higher levels than those of control. The presence of antibiotics (chlortetracycline) in hog loin meat were detected (0.08 ppm) in control sample. However, there was no antibiotic in other treated hog loin meats (T1, T2 and T3, respectively). The thiobarbituric acid reactive substances and volatile basic nitrogen values of the groups T2 (0.06 mg MA $kg^{-1}$ and 11.21 mg%, respectively) and T3 (0.05 mg MA $kg^{-1}$ and 8.23 mg%, respectively) were significantly (p<0.05) lower than that of control in loin meat. However, there was no significant difference between treated samples (T1, T2 and T3, respectively) and control in cooking loss and drip loss.

• Food Science and Preservation
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• v.24 no.7
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• pp.898-907
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• 2017

This study was aimed to test harvest time effect with polyethylene (PE) film liner, 1-methylcyclopropene (1-MCP) and aminoethoxyvinylglycine (AVG) treatments on fruit quality attributes in 'Sangjudungsi' persimmon fruit during cold storage. The fruits were harvested 10 days earlier in 2016 than the mature harvest time in 2015. The ethylene production was significantly lower in early harvested fruits than in mature harvested ones. Flesh firmness was maintained higher in 1-MCP treated fruit than in other treatments during cold storage. The rate of fruit weight loss was significantly inhibited by PE film liner treatment during storage, regardless of harvest time. 1-MCP treatment showed less change in fruit peel color variables ($L^*$ and $b^*$) from the calyx-end and equatorial regions during cold storage, compared with those from the control and PE film treatments. The incidence rate of fruit decay and softening was higher in PE film treated fruits than in the other treatments. However, there was no decay detected in AVG treated fruit. The early harvested fruits were maintained higher flesh firmness, compared with mature harvested fruits. Nevertheless, the mature harvested fruits showed much higher soluble solids content, the redness (Hunter a value) of the fruit peel and respiration rate, compared with early harvested fruits. Furthermore, the rate of weight loss in the fruit was remarkably inhibited in the PE film treatment.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.380-391
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• 2014

Plants as well as crops are damaged by a combination of the hot and dry winds that has been a major factor in the reduction of crop production. A means to protect them from damaging conditions is to consider a coating material. In this study, we established laboratory screening methods to find a coating material to protect a crop from rapid transpiration caused by various factors. In a test measuring the weight loss of kidney bean seedlings for 6 days, Avion treatments decreased its weight loss (P=0.05). Owing to long-time spend in completing this assay, we performed a more simple method using a cobalt chloride paper strip, which changes from blue to red colors under water condition. Beewax, guagum, paraffin liquid, soybean oil, and PE-635 gave a waterproofing effect above 37 and 43% at 0.5 and 1 h after treatment, respectively. However, these tested materials did not show significant waterproofing results at 2 h. Although the methods produced reasonable results, a screening method to obtain more objective data is needed. An alternative is to use an instrument that can detect the transpiration of crop leaves. In a preliminary test using barley leaves, a portable photosynthesis system showed transpiration inhibition of 2% soybean oil and 10 times-diluted Avion under field conditions. In another test using the leaves of maize seedlings and apricot tree, 2% liquid paraffin and plant oils such as apricot oil, linseed oil, olive oil, and soybean oil showed significant transpiration inhibition (P=0.05). Especially, paraffin liquid and soybean oil selected from above tests gave good transpiration inhibitory effects against rice at 2%. In addition, the mixture of 2% soybean oil and a spreader showed more elevated inhibition results comparing with soybean oil or the spreader alone indicating that the spreader may be attributed to more uniform diffusion of the hydrophobic material onto the leaf surface of maize seedlings. The hydrophobic material coated physically the stomata and cuticle layers on leaf surfaces of rice. These hydrophobic materials screened in this study are expected to be used as plant coating materials.

• Journal of Conservation Science
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• v.32 no.4
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• pp.471-490
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• 2016

This study investigated provenance of raw materials and making technique of lime-based materials used in the tomb barriers of the Yesan Mokri tombs from Joseon dynasty on the basis of analysis to material characteristics and physical properties. In the barrier materials, dry density and porosity are the highest value ($1.82g/cm^3$) and the lowest value (25.20%) in the south wall of No. 1 tomb, respectively. Dry density and porosity are inversely proportional in all barrier materials, but unconfined compressive strength, which is the highest value of $182.36kg/cm^2$ in the No. 2 tomb, does not show an interrelation with porosity and density. Mineral components in the lime-soil mixtures of the tomb barrier are mainly quartz, feldspar, mica and calcite about 200 to $600{\mu}m$ size with yellowish brown matrix. Hydrotalcite and portlandite are detected in the lime mixture, and kaolinite in the soils. The lime materials of the tomb barrier occurred in large quantities weight loss and variable endothermic peaks caused by decarbonization reaction of $CaCO_3$ in the range from 600 to $800^{\circ}C$ in thermal analysis. Making temperature of lime for the tomb barrier is presumed approximately about $800^{\circ}C$ based on the occurrences, compositions and thermal analysis. The tomb barriers are revealed to very wide composition ranges of major elements and loss-on-ignition (22.5 to 33.6 wt.%) owing to mixture of the three materials (lime, sand and clay). It is interpreted that low quality construction technique was applied as the limes are very heterogeneous mixture with aggregates, and curing of the lime was poorly processed in the tomb barriers. Possible limestone sources are distributed in many areas around the Mokri site where limestone conformation and quarries for commercial production are found within Yesan and Hongseong areas. Therefore, we estimated that raw materials were possibly supplied from the local mines near the Mokri site.

• Food Science and Preservation
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• v.24 no.8
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• pp.1103-1112
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• 2017

This study was performed to investigate the effects of different cooking methods (boiling, roasting, stir-frying, and deep-frying) on folate retention in 6 kinds of mushrooms (Beech-, button-, Juda's ear-, oak-, oyster-, and winter-mushrooms) frequently consumed in Korea. In order to assure reliability of analytical data, trienzyme extraction-L casei method was verified and analytical quality control was also evaluated. Folate contents of mushrooms varied by 6.04-64.82 g/100 g depending on the type of mushrooms. and were significantly affected by cooking methods. Depending on cooking methods, folate contents of mushrooms decreased by 22-48%, 2-31%, and 17-56% for Juda's ear-, oak- and oyster-mushrooms, respectively, while 17-90% of folate was increased in Beech mushroom. Overall, the largest weight loss was found in boiled mushrooms, but the lowest one in deep-fried samples. True folate retention rates considering processing factor were less than 100% for all cooked mushrooms except for Beech samples. Overall, folate loss was the largest by boiling with water but the smallest by deep-frying. Both accuracy and precision of trienzyme extraction-L-casei method were excellent based on a recovery close to 100% and coefficient variations less than 3%. Quality control chart of folate analysis (n=26) obtained during the entire study and an international proficiency test (z-score=-0.5) showed that trienzyme extraction-L casei method is reliable enough for production of national folate database.