• Korean Journal of Weed Science
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• v.30 no.4
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• pp.361-370
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• 2010

This study was carried out to establish the analytical method of MCPA residue in brown rice and rice straw by HPLC/UVD. When MCPA was extracted from sample under the pH 3.6 by adding acetone 200 mL and 1N-HCl 100 mL, the extraction efficiency was high by 87%. And purification efficiency was high by 83% when 5 mL of 1% methanol/acetonitrile was eluated by the florisil Sep-pak cartridge column. From spiking of $0.1{\mu}g\;mL^{-1}$ and $0.25{\mu}g\;mL^{-1}$ of MCPA to control sample, respectively, average recovery rate of MCPA in brown rice was 96.0% and 94.9% and that in rice straw was 92.5% and 88.2%, respectively. Precision of experiment was very high by relative standard deviation of 1.5% to 5.7%. In brown rice and rice straw treated with bentazone+MCPA (11+1.2%) of 30 kg and 60 kg per ha at 30 days after rice transplanting, respectively, maximum residue limit was under $0.05{\mu}g\;mL^{-1}$ of the recommended rate of Korean Food and Drug Administration. From the above results, the analytical procedure of MCPA in plants such as hydrolysis, saponification and derivatization were ommited, and retention time was faster and recovery rate was higher than the existed results of HPLC/UVD. Therefore, these results were greatly improved and seemed to be usefully applied for residue analysis of MCPA in plants.

• Journal of Wetlands Research
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• v.5 no.2
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• pp.15-32
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• 2003

The ecological study on seven wetlands of Haman area in Kyungsangnamdo, Korea, was carried out. In especial, the biological data of the sites were unknown. In this study, water quality including water temperature, pH, DO, COD, T-N, T-P, SS were tested. On the survey of plants and animals, vegetation and flora were investigated and the fauna of insects, fish, and amphibians were studied on each wetland. Water of wetland Oksu was heavily polluted and wetlands Pyungy and Dodulyangy were relatively clean. The water pollution was most severe in winter at all of the wetlands. Plant communities were classified into 9 natural communities and 1 artificial community. On the vegetation, wetland Sugok showed the highest plant taxa, and 41 families, 78 species and 16 varieties were classified. There was remarkable difference in number of plant taxa. The difference may be caused by the variances of wetland sizes, the influence from terrestrial environment. Wetland Sugok showed most rich insect fauna, and 10 orders, 76 families 224 species and 1082 individuals were identified. The species diversity was 2.05 and the species richness was 73.49. Wetland Ddun showed poor insect fauna, and 6 orders, 23 families, 29 species and 81 individuals were identified. Total collected fish were 4 orders, 7 families and 11 species. The fish fauna was most rich in wetlands Oksu and Pyungy, but poor in wetland Unan. Total collected amphibians were 2 orders, 3 families and 4 species.

• KSBB Journal
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• v.15 no.5
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• pp.489-496
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• 2000

Several culture systems including batch, two-stage CSTR, semi-fed batch, and two-stage cyclic fed-batch were investigated for the efficient production of the Fab fraction of PDC-E2 specific human monoclonal antibody using high cell density recombinant E. coli. A two-phase batch system and a two-stage continuous system were examined to overcome plasmid instability problems, by separating the growth and the production stages. The cell density and productivity of the two-stage continuous culture was better than that of the two-phase batch fermentation. In the two-stage continuous culture system with DO-stat, the cell growth and the productivity were superior to those of the system without the DO control. Also, almost total plasmid stability was maintained in the two-stage continuous culture system. Modified M9 medium was selected as an optimum feeding medium for the fed-batch process, and the optimum C/N ratio determined to be 2:3. The optimum feeding rate was $0.6g/\ell/hr$ for a constant feeding strategy in semi-fed batch system. When the feeding medium was fed by pulsing, it was observed that more frequent pulsing resulted in improved cell growth. The linear feeding method was the most efficient of the various feeding methods tested. Finally, high cell density culture using a two-stage cyclic fed batch system with pH-stat was tried because the linear feeding method showed limitations in terms of obtaining high cell densities, and a cell density of $54 g/\ell$ was achieved. It was concluded that the two-stage cyclic fed batch system was the most efficient system for high cell density culture of the systems tested. However, productivity improvements were lower than expected due to the extremely high accumulations of acetate, although the low levels of residual glucose were maintained.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.76-83
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• 1999

Studies were conducted during 2 months from May of 1997 to evaluate the effects of pig manure compost(PMC) on soil microbial flora. To do so, a field experiment of Chinese cabbage(Brassica campestris L.) was conducted in a randomized block design on a sandy loam soil and microbial floral characteristics in soils were analyzed. Treatments to control included the application of PMC at (A) $8Mg\;ha^{-1}$CM-8), (B) $29Mg\;ha^{-1}$(CM-2,9), and (C) $57Mg\;ha^{-1}$(CM-57), and of chemical fertilizer(D) at $320N-80P_2O_5-200K_2O\;kg\;ha^{-1}$(NPK). In each treatment, the rhizosphere and non-rhizosphere soils were tested for the analysis of microbial populations. The populations of bacteria, actinomycetes, and fungi increased in soils with the applications of PMC and chemical fertilizer, but that of Bacillus sp. decreased. However, the population of fluorescent Pseudomonas sp. was reduced in NPK plots only. With increasing application rates of PMC, the number of colony forming units(cfu) of bacteria (Pseudomonas sp. and actinomycetes) and fungi increased. in all PMC-treated plots, the population density peaked at early growth stage for bacteria(including Bacillus sp.), at late growth for fluorscent Pseudomonas sp., and at harvest for fungi and actinomycetes. The rhizosphere effect was greatest for fluorscent Pseudomonas sp. As the application rates of PMC increased, Total N, organic matter, available phosphate, and exchangeable -K, -Ca, and -Mg increased compared to control, but soil pH was lowered. In NPK plots, EC was 3.4-fold and exchangeable K was 5-fold higher than control.

• Journal of Aquaculture
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• v.13 no.4
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• pp.277-284
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• 2000

Rabbitfish hatchlings were given a mixed food of rotifers (Brachionus rotundiformis) and trochophore larvae of oyster. Only the oyster-trochophore larvae were found in the gut of 62-h old fish larvae. The fish larvae, fed on rotifer and ciliate alone did not survive. However, their survival increased to 3.3 % on the 10th day after hatching, when trochophore was supplemented. Corresponding with the accelerated growth, the number of rotifers consumed increased from 11 in a 5-day old fish to 165 in a IS-day old fish. In a field ecosystem containing live diatom, Nannochloropsis oculata, rotifers and copepods, fish larvae were shocked and the oyster's trochophore larvae were fed from 2 to 7 days after hatching. A total of 76,000 seedling were produced after 50 days of hatching with 12.7 % survival. Mean total length and body weight were 65.6 mm and 3.4 g, respectively. Growth of body length (BL), body height (BH), body weight (BW) and head length (HL) as a function of the total length (TL) showed regressional relationships as follows; BL=0.8565 TL+0.0852 ($t^2$=0.9996); BH=0.3207 TL - 0.5052 (($t^2$=0.9641) BW=0.0652 TL2.3508 (($t^2$=0.9925); HL=0.2595 TL - 0.1898 (($t^2$=0.9901)

• Journal of Life Science
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• v.25 no.9
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• pp.1027-1035
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• 2015

A strain GP32 which produces a highly viscous extracellular polysaccharide was conducted with soil samples and identified as Pseudomonas species. The culture flask conditions for the production of extracellular polysaccharide by Pseudomonas sp. GP32 were investigated. The most suitable carbon and nitrogen source for extracellular polysaccharide production were galactose and (NH₄)₂SO₄. The optimum carbon/nitrogen ratio for the production of extracellular polysaccharide was around 50. The optimum pH and temperature for extracellular polysaccharide production was 7.5 and 32℃, respectively. In batch fermentation using a jar fermentor, the highest extracellular polysaccharide content (15.7 g/l) was obtained after 70 hr of cultivation. The extracellular polysaccharide produced by Pseudomonas sp. GP32 (designated Biopol32) was purified by ethanol precipitation, cetylpyridinium chloride (CPC) precipitation, and gel permeation chromatography. Biopol32, which has an estimated molecular weight of over 3×10⁷ datons, is a novel polysaccharide derived from sugar components consisting of galactose, glucose, gulcouronic acid and galactouronic acid in an approximate molar ratio of 1.85 : 3.24 : 1.00 : 1.42. The solution of Biopol32 showed non-Newtonian characteristics. The viscosity of Biopol32 exhibited appeared to be higher at all concentration compared to that of zooglan from Zoogloea ramigera. An analysis of the flocculating efficiency of Biopol32 in industry wastewater (food, textile, and paper wastewater) revealed chemical oxygen demand (COD) reduction rates 58.4-67.3% and suspended solid (SS) removal rates 82.6-91.3%. Based on these results, Biopol32 is a possible candidate for industrial applications such as wastewater treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1364-1373
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• 2012

Four crossbred (75% Holstein Friesian) lactating dairy cows, with an average live weight of $418{\pm}5$ kg and $36{\pm}10$ d in milk were randomly assigned according to a $2{\times}2$ factorial arrangement in a $4{\times}4$ Latin square design to evaluate the effects of cassava hay (CH) and rice bran oil (RBO) on feed intake, nutrient digestibility, ruminal fermentation, milk yield, and milk composition. Factor A was non-supplementation or supplementation with CH in the concentrate. Factor B was supplementation with RBO at 0% or 4% in the concentrate mixture. The four dietary treatments were (T1) control (Concentrate with non-CH plus 0% RBO; C), (T2) Concentrate with CH plus 0% RBO (CH), (T3) Concentrate with non-CH plus 4% RBO (RBO), and (T4) Concentrate with CH plus 4% RBO (CHRBO). The cows were offered concentrate, at a ratio of concentrate to milk production of 1:2, and urea-lime treated rice straw was fed ad libitum. Urea-lime treated rice straw involved 2.5 g urea and 2.5 g $Ca(OH)_2$ (purchased as hydrated lime) in 100 ml water, the relevant volume of solution was sprayed onto a 100 g air-dry (91% DM) straw, and then covering the stack with a plastic sheet for a minimum of 10 d before feeding directly to animals. The CH based concentrate resulted in significantly higher roughage intake and total DM intake expressed as a percentage of BW (p<0.05). Ruminal pH, $NH_3$-N, BUN and total VFA did not differ among treatments, while RBO supplementation increased propionate, but decreased acetate concentration (p<0.05). Furthermore, the population of total ruminal bacteria was significantly lower on the RBO diet (p<0.05). In contrast, the total ruminal bacteria and cellulolytic bacteria on the CH diet were higher than on the other treatments. Supplementation with CH increased (p<0.05) F. succinogens and R. flavefaciens populations, whereas the populations of B. fibrisolvens and M. elsdenii were increased on the RBO diet. In addition, supplementation with CH and RBO had no effect on milk production and composition in dairy cows, while fatty acid composition of milk was influenced by RBO supplementation, and resulted in significantly lower (p<0.05) concentrations of both short-chain and medium-chain FA, and increased (p<0.05) the proportion of long-chain FA in milk fat, as well as significantly increased cis-9, trans-11 CLA and total CLA. In conclusion, RBO or CH exhibited specific effects on DMI, rumen fermentation, microbial population, milk yield and composition in lactating dairy cows, which were not interactions between CH and RBO in the diets. Feeding lactating dairy cows with RBO could improve fatty acid in milk fat by increasing cis-9, trans-11 CLA.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.3
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• pp.287-291
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• 1988

These studies were carried out to find out the polishing properties and cooking quality of the cut-polished barley. Naked barley, Youngsanbori which was produced in Chonnam province, Korea in 1981, was applied for this experiment. Polished barley was produced by the conventional method and cut-barley was manufactured by the method established by Wheat and Barley Research Institute. The yield of cut-polished barley was 68.2% and that of conventionally polished barley was 70.1 %. The ratio of length to width was 2.88 in cut-polished barley and that of conventionally polished barley was 1.36. And weight of 1,000 kernel was 9.5g in cut-polished barley and 18.5g in conventionally polished barley. Energy consumption was found to be 91.1kW/1,000kg in conventionally polished barley and 105kW/1,000kg in cut-polished barley. Whiteness, water uptake ratio and expanded volume of cooked barley were 45.5, 225.7 and 283% in conventionally polished barley and 49.5, 312.7 and 318% in cut-polished barley, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3483-3487
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• 2016

Background: Cigarette smoking is one of the leading causes of death in the world. Tobacco consumption has grave negative consequences for health so that it is important to understand the reasons and motivations towards cigarette smoking and barriers against quitting smoking among the young generation for developing effective policies to control this widespread problem. Materials and Methods: This cross-sectional survey was carried out at the Faculty of Medicine, Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia. A total of 438 young smokers participated from the University and the general population. Data were collected through anonymous, self-administered questionnaires in the Arabic language that contained questions about the reasons and motivations towards cigarette smoking and barriers against quitting smoking. The questionnaire also contained several questions regarding knowledge and attitude of the participants towards cigarette smoking. The data was analyzed on SPSS-16. Results: The mean age of the respondents was $22.9{\pm}3.48$, out of 438 subjects 87 (19.9%) were married, and 351 (80.1%) were unmarried, and 331 (75.6%) belonged to urban areas while 107 (24.5%) were from the rural areas. Responding to a question about a number of cigarettes smoked per day, 31% answered 11-20, 29% answered 21-30, and 25% answered 1-10. Questioned about smokers in the family, 34.5% responded more than one, with 19% for brother and 13% for father. About the reasons for not quitting smoking, 26% described lack of willpower, 25% had no reason, 22% said that people around me smoke, and 15.3% responded stress at home/work. The major motivation for smokers was smoker friends (42%), for 33.8% others, for 12% father/brother and 7.8% media. Conclusions: There are several avoidable and preventable reasons and barriers against quitting smoking. However, knowledge and attitude about smoking were good, and the majority of the smokers were well aware of the associated hazards. Therefore, there is a need to search out ways and means to help them to quit this addiction.

• Applied Microscopy
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• v.15 no.1
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• pp.31-58
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• 1985

The morphological study on different types of cells of reproductive organ including spermatogenesis in the adult planaria was performed to observe their cytochemical and ultrastructural characteristics. 1. Spermatogenesis The circular luminated material appears immediately inside the nuclear envelope of early spermatid and is found also in the nucleus of sperm, but typical acrosomal structures cannot be observed. Approximately ten of small-sized mitochondria occur around the nucleus in the transitional phase from primary spermatocyte to secondary spermatocyte, but in sperm a long mitochondrion is closely associated with nucleus, parellel to long axis of it. The sperm has a relatively long head connected with two tails via hollow neck. 2. Reproductive organ The penis bulb and the bursa stalk were observed. (1) Penis bulb The cells constituted penis bulb are classified into six types on the basis of ultrastructure of the cells and cytochemistry of the cytoplasmic granules. 1) A-type cells: These cells exhibiting low electron density are mainly occupied by large nucleus. These cells possess two different types of granules: highly electron-dense round granules with an average size of $0.9{\mu}m$, and electron-dense granules exhibit PAS-positive reaction. 2) B-type cells contain PAS-positive granules with the size of about $0.4{\mu}m$. They are rich in free ribosomes and mitochondria. 3) C-type cells are found to be dark cells due to high electron-density. These cells are largely occupied by large nucleus. 4) D-type cells: These cells are seen as light cells which have poorly developed cell organelles. 5) E-type tells: These cells contain a large number of glycogen granules which occupy most of cell. 6) F-type cells: These arc parietal epidermal cells surrounding the genital antrum. These cells are characterized by their finger-like shapes and the presence of a number of electron-dense, irregularly-shaped structures inside cells. The relatively large electron-lucent granules can be also found. The F-type cells possess numerous microvilli on their free surfaces. (2) Bursa stalk The cells constituted bursa stalk are classified into 3 types on the basis of cell shapes and presences of electron-dense or electron-lucent granules. 7) G-type cells with a long cytoplasmic process. They have large nuclei and poorly developed cell organelles. 8) H-type cells: These cells are characterized by the presence of a long cytoplasmic process and relatively highly electron-dense cytoplasmic profile. They have poorly developed cell organelles. 9) I-type cells contain large electron-lucent granules which exhibit negative reactions with three kinds of cytochemical staining methods used in this experiment. The fine electron-dense structures can be found inside these granules.