• Journal of Environmental Health Sciences
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• v.39 no.4
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• pp.360-368
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• 2013

Objectives: Phthalates are used in a large variety of products including as coatings of pharmaceutical tablets, film formers, stabilizers, dispersants, emulsifying agents, and suspending agents. They have been the subject of great public concern in recent years. The extensive uses of this material have attracted attention and issues regarding its safety have been raised. Methods: In this study, three types of phthalate skin permeation were studied using matrixes such as ointments, creams and lotions in vitro. The absorption of phthalate diesters [Dimethyl phthalate (DMP), Di-n-propyl phthalate (DPP) and Di-n-pentyl phthalate (DNPP)] using film former has been measured in vitro through rat skin. Epidermal membranes were set up in Franz diffusion cells and their permeability to PBS measured in order to establish the integrity of the skin before the phthalates were applied to the epidermal surface. Results: Absorption rates for each phthalate ester were determined and permeability assessment made to quantify any irreversible alterations in barrier function due to contact with the esters. Types of phthalate in vitro experimental results quickly appeared in the following order DMP > DPP ${\geq}$ DNPP. Conclusions: In the experimental results, lotion> cream> ointment, and the permeation rate of lotion with a great amount of moisture was the fastest. Skin permeation rate is generally influenced by the chemical characteristics of a given chemical, such as molecular weight and lipophilicity. As the esters became more lipophilic and less hydrophilic, the rate of absorption decreased.

• Parasites, Hosts and Diseases
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• v.51 no.5
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• pp.531-536
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• 2013

Morphological characteristics of Mesocestoides lineatus tetrathyridia collected from Chinese snakes and their adults recovered from experimental animals were studied. The tetrathyridia were detected mainly in the mesentery of 2 snake species, Agkistrodon saxatilis (25%) and Elaphe schrenckii (20%). They were 1.73 by 1.02 mm in average size and had an invaginated scolex with 4 suckers. Adult tapeworms were recovered from 2 hamsters and 1 dog, which were orally infected with 5-10 larvae each. Adults from hamsters were about 32 cm long and those from a dog were about 58 cm long. The scolex was 0.56 mm in average width with 4 suckers of 0.17 by 0.15 mm in average size. Mature proglottids measured 0.29 by 0.91 mm (av.). Ovaries and vitellaria bilobed and located in the posterior portion of proglottids. The cirrus sac was oval-shaped and located median. Testes were follicular, distributed in both lateral fields of proglottids, and 41-52 in number per proglottid. Gravid proglottids were 1.84 by 1.39 mm (av.) with a characteristic paruterine organ. Eggs were 35 by $27{\mu}m$ in average size with a hexacanth embryo. These morphological characteristics of adult worms were identical with those of M. lineatus reported previously. Therefore, it has been confirmed that the tetrathyridia detected in 2 species of Chinese snakes are the metacestodes of M. lineatus, and 2 snake species, A. saxatilis and E. schrenckii, play the role of intermediate hosts.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.305-309
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• 2013

A freesia (Freesia hybrida Hort.) 'Dancing Flame' was developed for the cut flower in the National Institute of Horticultural Herbal Science in 2007. This hybrid was selected from a crossing between a seedling 'Vulcano' and 'Sailor', which is scarlet double flowering and purple single flowering, respectively, and 'Figaro' which is bright red color and semi-double flowering, in 2000. Morphological characteristics of the selected hybrid were investigated for 3 years from 2005 to 2007, and then it was named 'Dancing Flame'. 'Dancing Flame' had red color (RHS R44B) and single flower with yellow center color (RHS Y9A). The growth of the plant was vigorous and the average height was 93.3 cm. The average flower width was 60 mm, number of floret per stalk was 14.3, and stalk was 13.2 cm length. The average yield, 7.8 cuttings per plant, was 2.5 stems per plant more than the control cultivar. The average days to first flowering of 'Dancing Flame', 133 days, was approximately 5 days earlier than the control cultivar. And its average yield, 7.1 cormlet per plant, was also 2.5times more than the control cultivar.

• Journal of Korean Society of Water and Wastewater
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• v.13 no.2
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• pp.66-73
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• 1999

This study was carried out to derive the removal characteristics of target materials(DOC and turbidity) during the coagulation process after the injection of coagulants(PACl and FeCl3). Used apparatus were a jar test and a pilot plant. A great portion of DOC among the total removed DOC was achieved at the slow mixing process among the coagulation process. The ranges of removed DOC and optimum pH for each coagulant were 0.45~1.47mg/l and 6.0~6.5 by PACl, and 0.97~2.61mg/l. and 5.0~5.5 by FeCl3, respectively. Both of coagulants showed little increase of DOC removal above coagulant dosage 20mg/l Molecular weight distribution(MWD) of removed DOC was measured by get filtration(GF) technique. The MWD variation by gel filtrationin(GF) for removed DOC in the coagulation process were as follows; for raw water, the percentages of each MWD for total area were < MW 6,500 25.5%, MW 6,500~66,000 67.1%, and > MW 66,000 7.4%. For the same coagulant dosage(12mg/l), the percentages of each MWD for total area by PACl were < MW 6,500 20.5%, MW 6,500~66,000 48.7%, and > MW 66,000 9.1%, and those of FeCl3 were MW 66,000 18.2%. For each coagulant, the removal percentage of MW 6,500~66,000 occurred a little, but at a part of

• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.270-276
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• 1999

In previous reports, the authors isolated the algicidal marine bacterium, Alteromonas sp. SR-14 and demonstrated its growth inhibition of diatom, Chaetoceros calcitrans (C. calcitrans). In this paper, we studied the effects of cell free culture filtrate of Alteromonas sp. SR-14 on the growth of C. calcitrans, and the characteristics of the algal growth inhibition substance. The culture filtrate of Alteromonas sp. SR-14 grown in peptone broth showed growth inhibition activity against C. calcitrans. The reasonable culture conditions of the bacterium for producing of algal growth inhibition substances were $15~20^{\circ}$ in temperature, 7.0-9.0 in pH and $23~30{\textperthousand}$ in salinity, respectively. The algal growth inhibition activity of culture filtrate was increased from stationary phase in growth curve of Alteromonas sp. SR-14. The molecular weights of algal growth inhibition substances produced by Alteromonas sp. SR-14 were ranged about from 3 KDa to 12 KDa. Among the substances, less than 10 KDa fraction were stable by heating at $100^{\circ}$ for 10 minutes, while more than 10 KDa fraction were heat labile. According to the experimental results, the algal growth inhibition substance produced by the bacterium was not a single compound.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.12
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• pp.1726-1735
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• 2014

This study investigated the effects of acarbose addition on changes in ruminal fermentation characteristics and the composition of the ruminal bacterial community in vitro using batch cultures. Rumen fluid was collected from the rumens of three cannulated Holstein cattle fed forage ad libitum that was supplemented with 6 kg of concentrate. The batch cultures consisted of 8 mL of strained rumen fluid in 40 mL of an anaerobic buffer containing 0.49 g of corn grain, 0.21 g of soybean meal, 0.15 g of alfalfa and 0.15g of Leymus chinensis. Acarbose was added to incubation bottles to achieve final concentrations of 0.1, 0.2, and 0.4 mg/mL. After incubation for 24 h, the addition of acarbose linearly decreased (p<0.05) the total gas production and the concentrations of acetate, propionate, butyrate, total volatile fatty acids, lactate and lipopolysaccharide (LPS). It also linearly increased (p<0.05) the ratio of acetate to propionate, the concentrations of isovalerate, valerate and ammonia-nitrogen and the pH value compared with the control. Pyrosequencing of the 16S rRNA gene showed that the addition of acarbose decreased (p<0.05) the proportion of Firmicutes and Proteobacteria and increased (p<0.05) the percentage of Bacteroidetes, Fibrobacteres, and Synergistetes compared with the control. A principal coordinates analysis plot based on unweighted UniFrac values and molecular variance analysis revealed that the structure of the ruminal bacterial communities in the control was different to that of the ruminal microbiota in the acarbose group. In conclusion, acarbose addition can affect the composition of the ruminal microbial community and may be potentially useful for preventing the occurrence of ruminal acidosis and the accumulation of LPS in the rumen.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.484-488
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• 1988

Two forms of extracellular endo-inulinase, designated as PIand P II were resolved from a species of Pseudomonas isolated from soil. Both enzymes were glycoproteins with their carbohydrate content of 15% for PIand 2.4% for P II inulinase. Tryptophan residue was proved to be an essential amino acid for their catalytic activity. The molecular weights of PIand P II were estimated to be 210, 000 and 170, 000, respectively. The activity of the two enzymes was strongly inhibited by p-chloromercuribenzoate but the inhibition was nearly completely offset by the addition of the reducing agents such as cysteine or dithiothreitol. On the other hand, the two enzymes were activated about 50-60% of their activities by the presence of Co$^{+2}$ ion, and quite stable at pH values ranging from pH 4.0 to 1.5. They also appeared to be relatively thermostable, and no appreciable inactivation was observed after incubation at 55$^{\circ}C$ for 2 hours. About 70 % hydrolysis rate with PIand 56 % with P II were achieved when inulin was hydrolyzed at 5$0^{\circ}C$ for 12 hours with 60 units of the enzymes in 2 % inulin solution.

• Membrane Journal
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• v.27 no.5
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• pp.441-448
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• 2017

In this study, the effects of membrane characteristics on the power generation performance in reverse electrodialysis (RED) have been investigated with pore-filled ion-exchange membranes (PFIEMs) prepared by employing a porous polyethylene substrate and the mixtures of three cross-linking agents. As a result, it was confirmed through the correlation analyses that the cross-linking degree and free volume of the PFIEMs were effectively controlled by mixing the cross-linking agents having different molecular sizes, influencing complexly the electrochemical characteristics of the membranes and the power generation performance in RED. In particular, the pore-filled cation-exchange membranes at the optimum cross-linking conditions exhibited the power generation performance superior to that of the commercial membranes and the pore-filled anion-exchange membranes also showed the excellent performance close to that of the commercial membrane.

• Journal of Korea Soil Environment Society
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• v.3 no.2
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• pp.53-60
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• 1998

The influence of venting on the leaching characteristics of pure gasoline and gasoline contaminated soil was studied. The change of leaching characteristics by venting of contaminated soil column could be characterized by two distinct trends : 1) the leaching concentration in TPH-GRO rapidly decreased with evaporation until the evaporation loss became 75% of the original volume. Afterwards, it gradually decreased. 2) the leaching concentrations of individual components showed initial increase followed by gradual decrease. In general, the relative increase of leaching concentration and the venting time to reach the maximum increased with the molecular weight of the components. It should be noted that the decrease of gasoline concentration in the vented air occurs faster than that in the leaching solution. This indicates that, after removing most of the gasoline by evaporation, the focus of the risk assessment for the residual contaminants should be on the groundwater contamination rather than air pollution.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.2
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• pp.201-212
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• 2011

Nanotechnology is the applied science which develops new materials and systems sized within 1 to 100 nanometer, and improves their physical, chemical, and biological characteristics by manipulating on an atomic and molecular scale. This nanotechnology has been applied to wide spectrum of industries resulting in production of various nanoparticles. It is expected that more nanoparticles will be generated and enter to natural water bodies, imposing great threat to potable water resources. However their toxicity and treatment options have not been throughly investigated, despite the significant growth of nanotechnology-based industries. The objective of this study is to provide fundamental information for the management of nanoparticles in water supply systems through extensive literature survey. More specifically, two types of nanoparticles are selected to be a potential problem for drinking water treatment. They are carbon nanoparticles such as carbon nanotube and fullerene, and metal nanoparticles including silver, gold, silica and titanium oxide. In this study, basic characteristics and toxicity of these nanoparticles were first investigated systematically. Their monitoring techniques and treatment efficiencies in conventional water treatment plants were also studied to examine our capability to mitigate the risk associated with nanoparticles. This study suggests that the technologies monitoring nanopartilces need to be greatly improved in water supply systems, and more advanced water treatment processes should be adopted for better control of these nanoparticles.