• Horticultural Science & Technology
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• v.34 no.1
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• pp.67-76
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• 2016

This study was conducted to examine the optimal environmental condition for promoting the growth of sowthistle as affected by light quality and photoperiod in a closed-type plant production system. Seeds were sown in 240-cell plug trays and then germinated for 3 days at a 24-hour photoperiod in a closed-type plant production system with LED lights (R:B:W = 8:1:1). Seedlings were transplanted and grown under 3 types of LED (R:B:W = 8:1:1, R:W = 3:7, or R:B = 8:2) and 4 photoperiods (24/0, 16/8, 8/16, or 4/20 hours) with $230{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light intensity at a density of $20cm{\times}20 cm$. The experimental design was a randomized complete block design. Plants were cultured for 40 days un der the condition of $21{\pm}2^{\circ}C$ and $70{\pm}10%$ relative humidity after transplanting. Plants were fed with a recycling nutrient solution (pH 7.0 and EC $2.0dS{\cdot}m^{-1}$) contained in a deep floating tank. Fresh weight and dry weight of shoot or root, leaf length, and leaf area were the greatest in the photoperiod of 24/0 (light/dark) with RW LED. The highest number of leaves occurred in the photoperiod of 16/8 (light/dark) with RB LED, while the incidence of tip burn was higher in the photoperiod of 24/0 (light/dark) compared to the other treatments. Chlorophyll value was the highest in the 16/8 (light/dark) photoperiod and there was no significant difference by light quality. Chlorophyll fluorescence was the lowest in the photoperiod of 24/0 (light/dark) compared with other treatments. Therefore, in terms of economic feasibility and productivity for Ixeris dentata Nakai cultivation in a closed-type plant production system, the results obtained suggest that plants grew the best when kept in a photoperiod of 16/8 (light/dark) and light quality of combined LED RW (3:7).

• Applied Microscopy
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• v.30 no.4
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• pp.357-365
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• 2000

Paneth cells have been suggested to contribute to the elimination of excess metals into the intestinal lumen. The purpose of this study wat to investigate the changes of the zinc pools in rats subjected to functional loading with zinc salt by mean of both light and electron microscopical autometallography (AMG). Wistar rats 4 were administrated with zinc chloride (20 mg/kg body weight) intraperitoneally dissolved in 1 ml distilled water. The control group received 1 ml saline IP. After further one hour the animals were transcardially perfused with 0.4% sodium sulphide dissolved in 0.1 M PB fellowed by 3% glutaraldehyde solution for 10 minutes. Pieces of ileum were frozen with solid $CO_2$ and sectioned on a cryostat. The sections $(20{\mu}m)$ were autometallographically developed. Sections selected for EM were reembedded on top of a blank Epon block, from which ultrathin sections (100 nm) were cut. The ultrathin sections were double stained with uranyl acetate (30 min) and lead citrate (5 min), then examined under electron microscope. Studies of comparable sections from control and zinc loaded animals with the AMG selenium method gave quite different results. The control animals demonstrated a weakly positive staining in the cytoplasm of the Paneth cells. In the electron microscope the AMG silver grains were found to be located in the cytoplasm, while the electron dense secretary granules and other cell organelles were void of staining. Few AMG grains were located at the apical surface of the Paneth cells. In sections from zinc loaded rats, the AMG grains were seen in abundance in the lumen of the Lieberkuhn crypts at light microscopic levels. At EM levels the zinc revealing silver grains were located in the cytoplasm as in the controls, but much more AMG grains were shifted into the secretary granules. Furthermore, profound AMG grains were found in the lumen of the crypts and surrounding vessels. And a few grains were seen in the endothelium. The AMG technique demonstrated a pattern of AMG grains in the Paneth cells that strongly suggests a transport of zinc ions through these cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.300-307
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• 1997

The effects of Aster scaber and Ixeris dentata on cadiovascular system in hyperlipidemic rats were examined. Five groups of thirty Sprague Dawley rats were fed with the diet contained 1% cholesterol, 0.25% sodium cholate, 10% coconut oil and 5% lard(control group) for 4 weeks. Each experimental diet group was added with 5% plant powder or extract of the 5% plant powder by dry weight. Contractile or relaxation responses in the isolated artria and thoracic aortae were measured and the morphological changes of the aortic endotherium from the rats fed the experimental diet were inspected. In response to isoproterenol, the number of right atrial spontaneous beat was significantly lower in Cham chyi powder group$(PP_{1})$ and Sumbagui powder group$(PP_{2})$ than control at $10^(-8)M$ concentration. The contraction forces by injection of phenylephrine and calcium in isolated thoracic aorta were significantly low in each experimental groups compared with the control. The relaxation rates by acetylcholine represented comparatively higher value in $PP_{1}$ than control. The morphological changes of endothelial cell surface was a little in $PP_{1}$ and $PP_{2}$ compared with control, while the damages were considerably advanced in Cham chyi and Sumgbagui extract diet group$(PE_{1},\;PE_{2})$.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.249-254
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• 2002

To determine the abilities as both lactic starter and probiotics for fermented foods, we investigated the potency of acid production, proteolytic activity and lactose metabolism of Lactobacillus amylovorus IMC-1. And the strain was cultured with lactococci in 10% skim milk medium. It was also examined the bactericidal action of antibacterial substance, produced by the strain IMC-1, against pathogenic bacteria. L. amylovorus IMC-1 showed excellent production of acid in 10% skim milk supplemented with yeast extract, and produced 0.8 and 2.7% of acid at 12 and 72 h incubation, respectively. It was found that the activity of ${\beta}-galactosidase$, about $39\;{\mu}M/minute/dry$ cell weight (mg), was stronger than that of $phospho-{\beta}-galactosidase$ in the strain IMC-1. The strain showed weak proteolytic activity in 10% skim milk, thus it produced 6 and $69\;{\mu}g/mL$ of free tyrosine at 12 and 72 h cultivation, respectively. It was known that the strain utilized mainly ${\alpha}-casein$ than ${\beta}-casein$ from patterns of SDS-PAGE. Mixed culture produced more acid than single cultures of L. amylovorus IMC-1 and Streptococcus thermophilus NIAI 510. Single culture of Str. thermophilus and mixed culture showed increasing cheese flavor with incubation times. Optimal fermentation time of mixed culture for the acid production and flora of lactic starter was 16 and 12 h by adding 0.1 and 0.5% of yeast extract to 10% skim milk, respectively. Antibacterial substance produced by the strain IMC-1 reduced about 2 log of the viable cell counts of both Escherichia coli O157 and Shigella flexneri after 24 and 4 h incubation, and they were not detected after 48 and 6 h incubation, respectively.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.67-73
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• 2005

Photoautotrophic bacteria are promising candidates for the production of poly(3-hydroxybutyrate) (PHB) since they can address the critical problem of substrate costs. In this study, we isolated 25 Tn5-inserted mutants of the Synechocystis sp. PCC 6803 which showed enhanced PHB accumulation compared to the wild-type strain. After 5-days cultivation under nitrogen-limited mixotrophic conditions, the intracellular levels of PHB content in these mutants reached up to $10-30\%$ of dry cell weight (DCW) comparable to $4\%$ of DCW in the wild-type strain. Using the method of inverse PCR, the affected genes of the mutants were mapped on the completely known genome sequence of Synechocystis sp. PCC 6803. As a result, the increased PHB accumulation in 5 mutants were found to be resulted from defects of genes coding for NADH-ubiquinone oxidoreductase, O-succinylbenzoic-CoA ligase, photosystem II PsbT protein or histidine kinase, which are involved in photosystem in thylakoid inner membrane of the cell. The values of $NAD(P)H/NAD(P)^+$ ratio in the cells of these mutants were much higher than that of the wild-type strain as measured by using pulse-amplitude modulated fluorometer, suggesting that PHB synthesis could be enhanced by increasing the level of cellular NAD(P)H which is a limiting substrate for NADPH-dependent acetoacetyl-CoA reductase. From these results, it is likely that NAD(P)H would be a limiting factor for PHB synthesis in Synechocystis sp. PCC 6803.

• Tuberculosis and Respiratory Diseases
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• v.43 no.4
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• pp.579-589
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• 1996

Background : Activation of neutrophil is critical for the clearance of microorganisms and toxic host mediators during sepsis. Unfortunately the activated neutrophil and its toxic byproducts can produce tissue injury and organ dysfunction. The leucocyte CD11/18 adhesion complex regulates neutrophil-endothelial cell adhesion, the first step in neutrophil migration to sites of injection and inflammation. To investigate the potential of neutrophil inhibition as a treatment strategy for sepsis, we evaluated the effects of monoclonal antibody against CD11b (MAb 1B6) in rats intrabronchial challenged with Escherichia coli. Methods : Animals were randomly assigned to receive monoclonal antibody against CD11b (1 mg/kg, sc) and bovine serum albumin(BSA, 1 mg/kg, sc) 6 hr before, at 0 and 6 hr after intrabronchial challenge of $20x10^9$ CFU/kg E. coli 0111. Animals were randomized to treat either 24, 60 or 90% oxygen after bacterial challenge and begining 4 hr after inoculation, all animals were received 100 mg/kg ceftriaxone qd for 3 days. Peripheral and alveolar neutrophil(by bronchoalveolar lavage) counts and lung injury parameters such as alveolar-arte rial $PO_2$ difference, wet to dry lung weight ratio and protein concentration of alveolar fluid were measured in survived rats at 12 hr and 96 hr. Results : Monoclonal antibody against CD11b decreased circulating and alveolar neutrophil especially more in 12 hr than in 96 hr The lung injury parameters of antibody-treated animals were not different from those of BSA-treated animals. but It was meaningless due to small number of survived animals. The early(6 hr) mortality rate was significantly increased in antibody-treated group(51%) compared to BSA-treated group(31%) (P=0.02) but late(from 12 hr to 72 hr) mortality rate was not different in antibody-treated group(44%) from BSA-treated group(36%) (P =0.089). Conclusion : Leucocyte CD11b/18 adhesion molecule is known to regulate neutrophil migration to the site of infection and inflammation. The monoclonal antibody against CD11b decreased alveolar neutrophil in rats with pulmonary sepsis and increased early mortality rate. Therefore, we can speculate that monoclonal antibody against CD11b blocks of alveolar recruitment of neutrophils, impairs host defense mechanism and increases early mortality rate of pulmonary sepsis in rat.

• Journal of Bio-Environment Control
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• v.26 no.1
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• pp.35-42
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• 2017

This research was conducted to investigate the influence of post-planting fertilizer concentrations on the growth of seedlings and changes of nutrient concentrations of media in tomato seedling production through sub-irrigation. Two root media such as peat moss (grade of 0 to 6 mm, PM06) plus perlite (grade of 1 to 2 mm (PE2)(7:3, v/v) and peat moss (grade of 5 to 15 mm, PM515) plus PE2 (7:3, v/v) were formulated and filled into 72-cell plug trays. After seeds of 'Dotaerang Dia' tomato were sown and germinated at $28^{\circ}C$, the trays were moved to greenhouse and seedlings were raised 35 days. When the cotyledons were emerged, post-planting fertilizers of 13-2-13, 15-0-15 and 20-9-20 ($N-P_2O_5-K_2O$) were applied in a sequence. The fertilizer concentrations based on N in each plug stage were differed with $25mg{\cdot}L^{-1}$ in three treatments. The fertilizer solutions were supplied when the weight of plug trays decreased to 40 to 50% compared to container capacity. The root media were collected in 1, 2, 4, and 5 weeks after sowing and were divided into top, middle, and bottom parts, then were analysed for pH, EC and macro-nutrient concentrations. The seedling growth was investigated 5 weeks after sowing. The pH and EC in PM06+PE2 was higher than those of PM515+PE2. The bottom and mid-part had higher pH and lower EC compared to upper part in each medium. The differences of EC between upper and bottom parts were around 2 times in each medium. The $NH_4-N$ and K concentrations in program 3 of PM06+PE2 showed the highest concentrations among all treatments. The $NO_3-N$ concentrations in PM06+PE2 increased gradually and this rising tendency become severe as post-planting fertilizer concentrations were elevated. The seedling growth in terms of fresh and dry weights was the highest in the treatment of program 2 in PM06+PE2 among all treatments tested. Above results indicate that the gradual increases of fertilizer concentrations from 25 to $125mg{\cdot}L^{-1}$ in plug stages 2, 3, and 4 plug stages are desirable for

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.573-582
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• 2005

This study was conducted to investigate effects of the brown seaweed waste(BSW) supplementation on milk production and related endocrine response in serum in Holstein dairy cows. A total of 14 Holstein dairy cows(initial mean live weight 625kg, average lactation days 225, Reproduction 2.4) were randomly allocated into control(basal diet) and treatment groups (4% BSW/basal diet) with 7 replications for 90 days. Dry matter intake was not affected by brown seaweed waste supplementation, but daily milk yield(kg) at the last experiment significantly increased (6.25kg) in treatment group compared with control group(p<0.05) at the last experiment. The plasma insulin-like growth factor(IGF)-1, triiodothyronine($T_3$) and thyroxine($T_4$) levels were significantly increased in treatment group compared with control group(p<0.05), although the concentration of plasma growth hormone(GH) was not significantly different. Milk composition was not significantly different between groups. The somatic cell count(SCC) in milk were significantly reduced in treatment group compared with control group(p<0.05), but antibodies(total IgG, G1, G2) were not significantly different between groups. Therefore we strongly believe that the increased milk yield is related to metabolic hormones as IGF-1, $T_3$ and $T_4$ and the mechanism of reducing SCC in milk must do more study related nonspecific immunsystem in the future.

• Korean Journal of Pharmacognosy
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• v.5 no.2
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• pp.111-124
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• 1974

The radioactive compound sodium $acetate-U-C^{14}\;(C^{14}-acetate)$ was administered to two- and four-year-old July and September American ginseng (Araliaceae, Panax quinquefolium L.) plants and cuttings. The $C^{14}-acetate$ uptake was approximately 99%. The autoradiochromatograms suggest that the saponins isolated by preparative thin-layer chromatography contained impurities, especially those isolated from the leaf and stem extracts. The root and fruit methanol extracts yielded relatively pure saponins. The large amounts of panaquilin B and its proximity to panaquilin C on preparative thin-layer plates resulted in some admixing. The average concentration (% plant dry weight) of semi-purified saponins were high in the leaves (13.8%), as compared to fruits (9.8%), stems (7.9%) and roots (6.3%). The average percentage of $C^{14}-acetate$ incorporation into panaquilins was 4.8%. The average percentage of $C^{14}-acetate$ incorporation into panaquilins B and C was higher (1.40% and 1.13%, respectively) than that into panaquilins C, (d), G-1 and G-2 (0.75%, 0.65%, 0.13% and 0.53%, respectively). Panaquilin synthesis may be depending upon the part, collection period and age of the plant. The average percentage of $C^{14}-acetate$ incorporation into panaquilin B is high in roots (0.58%) and stems (0.48%); that into panaquilins C and (d) high in leaves (0.40% and 0.45%, respectively); and that into panaquilin E high in roots and leaves (0.55% and 0.50%, respectively). Panaquilin G-2 was synthesized in all parts of plants. The panaquilins appear to be biosynthesized more actively in July than September (exception-panaquilin G-1). Panaquilins B, C and G-1 may be biosynthesized more actively in four-year-old plants and panaquilins (d) and E more actively in two-year-old plants. The results from expectance with cuttings suggest that the panaquilins are synthesized de novo in the above-ground parts of ginseng plants, and that panaquilin G-1 may be synthesized de novo in the leaf. It is known from the tissue culture studies that panaquilins are produced by leaf, stem and root callus tissues and cailus-root cultures of American and Korean ginseng plants. Panaquilins may actively be synthesized de novo in most any cell or organ of the ginseng plants. It was verified that $C^{14}-acetate$ was incorporated into the panaxadiol portions of the panaquilins of two-year-old plants (sp. act. 0.56 mmcCi/mg) and four-year-old plants $(sp.\;act.\;0.54\;m{\mu}Ci/mg)$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.272-277
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• 1998

Filtering rates of two farming ascidians Styela clava and S. plicata, and of a farming mussel Mytilus edulis were experimentally investigated with reference to effects of water temperature and size. Absorptiometric determinations of filtering rates were carried out in a closed system with experimental animals being decreased indicate dyes neutral red. Optical density (OD) of 440 nm in path length 22 mm cell used as the indication of food particles absorption was appeared directly in proportion with the concentration of neutral red dyes. The filtering rate F is calculated by Kim's equation $F\;=\;V(1-e^{-z})$, where V is the water volume ($\ell$) in the experimental jar, and Z is the decreasing coefficient of OD as meaning of instantaneous removal speed as In $C_t\;=\;In\;C_{o}-Z{\cdot}t$, in this formula $C_t$ is OD at the time t. Filtering rate of S. clava increased as exponential function with increasing temperature while not over critical limit, and the critical temperature for filtering rate was assumed to be between $28^{\circ}C$ and $29^{\circ}C$. In case of S. plicata, the critical temperature was to be below $13^{\circ}C$, and through the temperature range $15\~25^{\circ}C$ appeared a little difference in level even though with significant. M. edulis was not appear any significant effects by water temperature less than $29^{\circ}C$. The model formula derived from the results is as below, where F is filtering rate (${\ell}/hr/animal$), T is water temperature ($^{\circ}C$), and DW is dry meat weight (g) of experimental animal. $$S.\;Clava;\;F\;=\;e xp\;(0.119\;T-4.540)\;(DW)^{0.6745},\;T<29^{\circ}C$$) $$S.\;plicata;\;F\;=\;e xp\;(A_t)\;(DW)^{0.5675},\;(13^{\circ}C $$[A_t =-8.56+0.6805\;T-0.0153\;T^2]$$ $$M.\;edulis;\;F\;=\;0.3844\;(DW)^{0.4952},\;<29^{\circ}C$$)