• The Korean Journal of Malacology
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• v.29 no.1
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• pp.23-32
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• 2013

The purpose of this study is to evaluate the effects of oil dispersant and ultraviolet (UV) radiation on the toxicity of crude oil. The toxicity of water-accommodated fraction (WAF) and chemically enhanced water-accommodated fraction (CEWAF) of Hebei Spirit crude oil was investigated in the embryo of the Manila clam, Ruditapes philippinarum with- and without ultraviolet radiation. The WAF and CEWAF with- and without UV radiation affected significantly the embryonic development of R. philippinarum. The EC50s of WAF without UV, WAF with UV, CEWAF without UV, and CEWAF with UV were 2.82, 0.79, 1.60, and 0.45 g/L, respectively. CEWAF was 1.6 times more toxic than WAF. UV radiation increased crude oil toxicity to 3.6 times for both WAF and CEWAF. The oil dispersant and UV radiation did not affect the acute toxicity to the embryo but retarded the period of embryonic development up to 26%. R. philippinarum proved to be a sensitive species to reflect the toxic effects of oil spill combined with oil dispersant and UV radiation. It is suggested that the chemical analyses on the WAF and CEWAF is important for the identification and quantitative explanation of the phototoxic compounds in crude oil.

• Environmental Analysis Health and Toxicology
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• v.24 no.4
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• pp.311-320
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• 2009

The short term (24-hr) and long term (21 days) effects of copper, cadmium, fenbendazole and sulfathiazole on the survival of the Korean fairy shrimp Branchinella kugenumaensis were evaluated. The 24-hr median lethal concentrations ($LC_{50}$) of copper, cadmium, fenbendazole, and sulfathiazole were 39, 512, 182, and 31,818 ${\mu}g/L$, respectively. The toxicity of copper is highest among 4 chemicals used in this study, while sulfathazole the lowest. After the long term (21 days) exposure experiment, the $LC_{50}$ copper, cadmium, fenbendazole, and sulfathiazole were 1.12, 2.1, 0.1, 6.6 ${\mu}g/L$, respectively. The long term effects of antibiotics were highly enhanced while the short-term effects were not strong. The sensitivities of B. kugenumaensis to copper and cadmium were higher than or comparable to those of other freshwater branchiopods (Streptocephalus spp., Thamnocephalus sp.), and far higher than the marine species (Artemia sp.). There were significant effects on the survival of B. kugenumaensis after long term exposure to relatively lower concentrations of copper, cadmium, fenbendazole and sulfathiazole. Therefore, B. kugenumaensis seems quite a good candidate species for the ecotoxicological assessments of freshwater environments.

• Nuclear Engineering and Technology
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• v.54 no.5
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• pp.1909-1913
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• 2022

This work shows the technical feasibility to obtain uranium tetrafluoride through an electrochemical mercury cell. This technique represents a custom scaling-up methodology from our previous studies to obtain UF₄ using the dropping mercury electrode cell. The UF₄ products were obtained from natural UF₆ gas, which was hydrolyzed to obtain a 50 g/L UO₂F₂ solution. The electrolysis cell was made using a mercury reservoir, to reach UF₄ production rates of 1 Kg UF₄/day. This custom design allowed a stable UF₄ production thanks to the mercury cathode, which do not permit the accumulation of solid products in its surface. The cell was tested using current densities from 5.000 to 17.500 A/m² and temperatures from 25 to 65 ℃. The maximum current efficiency achieved under these conditions was 80%. The UF₄ powders possessed spherical morphology, with diameters between 20 and 80 ㎛. Compared to the SnCl₂ precipitation, this process did not allow preferential growth of the precipitates. This improved the compaction of the UF₄ - Mg powders mixtures, with densities between 3.0 and 3.5 g/cm³. The purity of the UF₄ products was over 98%.

• Journal of Microbiology and Biotechnology
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• v.32 no.4
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• pp.464-472
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• 2022

An endo-polygalacturonase (endo-PGase) exhibiting excellent performance during acidic fruit juice production would be highly attractive to the fruit juice industry. However, candidate endo-PGases for this purpose have rarely been reported. In this study, we expressed a gene from Penicillium oxalicum in Pichia pastoris. The recombinant enzyme PoxaEnPG28C had an optimal enzyme activity at pH 4.5 and 45℃ and was stable at pH 3.0-6.5 and < 45℃. The enzyme had a specific activity of 4,377.65 ± 55.37 U/mg towards polygalacturonic acid, and the K_m and V_max values of PoxaEnPG28C were calculated as 1.64 g/l and 6127.45 U/mg, respectively. PoxaEnPG28C increased the light transmittance of orange, lemon, strawberry and hawthorn juice by 13.9 ± 0.3%, 29.4 ± 3.8%, 95.7 ± 10.2% and 79.8 ± 1.7%, respectively; it reduced the viscosity of the same juices by 25.7 ± 1.6%, 52.0 ± 4.5%, 48.2 ± 0.7% and 80.5 ± 2.3%, respectively, and it increased the yield of the juices by 24.5 ± 0.7%, 12.7 ± 2.2%, 48.5 ± 4.2% and 104.5 ± 6.4%, respectively. Thus, PoxaEnPG28C could be considered an excellent candidate enzyme for acidic fruit juice production. Remarkably, fruit juice production using hawthorn as an material was reported for the first time.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.3
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• pp.388-395
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• 2009

The current study was conducted to investigate the effect of early feed restriction (FR, 8 to 14 d of age) on growth performance and immune function in broiler chickens. Birds were fed corresponding diets from 3 to 35 d of age, which consisted of three phases: starter (3 to 7 d of age), FR (8 to 14 d of age) and re-alimentation (15 to 35 d of age) phases. During the FR period, each group of birds was fed the basal diet ad libitum (CON), 85% (EN85) and 70% (EN70) of lower calorie diet ad libitum (qualitative FR), and 85% (FI85) and 70% (FI70) of voluntary intake on a daily basis (quantitative FR). As a result, there was no statistical difference in weight gain, feed intake and feed conversion ratio between the CON and quantitative or qualitative FR groups during the entire (3 to 35 d) periods. In particular, the EN85 group resulted in a significant (p<0.05) increase in weight gain compared with the EN70, FI85 and FI70 groups. Plasma total protein and albumin at 14 d of age (during FR) were significantly (p<0.05) lower in the quantitative and qualitative FR groups, but these parameters at 35 d of age (after re-alimentation) were higher (p<0.05) in the EN85 and EN70 groups than in the CON group. Plasma IgG level was unaffected by dietary FR procedure. In cytokines, there was no significant difference in the expression of lymphocytic IL-4 and IFN-${\gamma}$ at 14 d of age between the FR and the CON groups, whereas lymphocytic IL-6 and iNOS expression were significantly (p<0.05) lower in FI85 and FI70 groups. Moreover, lymphocytic iNOS was also significantly (p<0.05) lower in birds fed qualitative and quantitative diets compared with those fed ad libitum. In the thymus, IL-4 expression was higher (p<0.05) in FI85 and FI70 groups, whereas IL-6 expression was lower (p<0.05) in the FI85 and FI70 groups than in the CON group. Thymic iNOS was significantly (p<0.05) lower in birds fed qualitatively and quantitatively restricted diets compared with those fed ad libitum. At 35 d of age, there was no difference in the expression of IL-4, IL-6 and IFN-${\gamma}$ of lymphocytes and thymus between the FR and CON groups. In conclusion, 85% of quantitative and qualitative FR would have a beneficial effect on the expression of some cytokines including IL-4 and iNOS without change in growth performance of birds.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.367-372
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• 2005

Antimicrobial effects of the extracts from Castanea crenata leaf were investigated. The antimicrobial effects of methanol extract (8 mg, 20 mg) of 0.2 g and 0.5 g. eq. of Castanea crenata leaf was stronger than that of 0.65 mg of benzoic acid against Gram(+) bacteria such as Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Leuconostoc mesenteroides and Bacillus subtilig and Gram(-) bacteria such as Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa. Growth inhibition of various microorganisms was observed in Castanea crenata leaf, therefor the Castanea crenata leaf were solvent fractionated. The ethyl acetate-soluble acidic and phenolic fraction were showed remarkable antimicrobial activity against microorganisms tested. The acidic fraction was purified with silica gel adsorption column chromatography, Sephadex LH-20 column chromatography and HPLC, subsequantly. The antimicrobial active substance isolated from the acid fraction of Castanea crenata leaf was characterized as stigmast-5-en-3-ol($\beta$-sitosterol) by MS and NMR analysis.

• Archives of Pharmacal Research
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• v.28 no.5
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• pp.550-556
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• 2005

The flower of Campsis grandiflora K. Schum. Was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and H$_2$O. From the EtO Ac fraction, seven triterpenoids were isolated through the repeated silica gel, ODS column chromatographies and preparative HPLC. From the result of physico- chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as 3${\beta}$-hydroxyolean-12-en-28-oic acid (oleanolic acid, 1), 3${\beta}$-hydroxyurs-12-en-28-oic acid (ursolic acid, 2), 3${\beta}$-hydroxyurs-12-en-28-al (ursolic aldehyde, 3), 2${\alpha}$,3${\beta}$-dihydroxyolean-12-en-28-oic acid (maslinic acid, 4), 2${\alpha}$,3${\beta}$-dihydroxyurs-12-en-28-oic acid (corosolic acid, 5), 3${\beta}$,23-dihydroxyurs-12- en-28-oic acid (23-hydroxyursolic acid ,6) and 2${\alpha}$,3${\beta}$,23-trihydroxyolean-12-en-28- oic acid (arjunolic acid, 7). These teriterpenoids were isolated for the first time from this plant. Also, compounds 4, 5, 6, and 7 revealed relatively high hACAT-1 inhibitory activity with the value of 46.2${\pm}$1.1, 46.7${\pm}$0.9, 41.5${\pm}$1.3 and 60.8${\pm}$1.1% at the concentration of 100${\mu}$g/mL, respectively.

• Journal of Gastric Cancer
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• v.1 no.4
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• pp.210-214
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• 2001

Purpose: The aim of this study was to evaluate the shortterm outcome of a jejunal interposition, by comparing it with a conventional Roux-en-Y gastrojejunostomy, after a total gastrectomy. Materials and Methods: For 28 patients (20 men and 8 women) with a gastric adenocarcinoma, who underwent an isoperistaltic simple jejunal interposition, weight, hemoglobin, hematocrit, serum protein and albumin, and cholesterol levels were checked before the operation and at 1 year and 2 years after the surgery. Also, endoscopy was performed to confirm reflux esophagitis. In this study, the data were collected between January 1993 and July 1999 at Chungnam National University Hospital, and the results were compared with those of the Roux-en-Y procedure. Results: The body weights at 1 year and 2 years after the surgery had returned to $86.0\%$ and $87.6\%$ of the recent original body weight in the jejunal interposition (JI) group and to $90.8\%,\;87.0\%$, respectively in the Roux-en-Y (RY) group. The levels of hemoglobin (g/dl) were 13.3, 12.5, and 11.9 in the JI group, and 13.8, 12.6, and 12.1 in the RY group at the time of the operation and at 1 year, and 2 years after the surgery, respectively. The total serum protein (g/dl) levels were 7.1, 7.2, and 7.5 in the JI group and 7.1, 7.0, and 7.2 in the RY gropu at the time of the operation and at 1 year and 2 years after the surgery, respectively. The serum albumin (g/dl) levels were 4.2, 4.1, and 4.2 in the JI group and 4.2, 4.2, and 4.2 in the RY group at the time of the operation and at 1 year, and 2 years after the surgery, respectively. The total serum cholesterol (mg/dl) levels were 186.5, 174, and 164 in the JI group and 213.7, 171.1, and 141.0 in the RY group at the time of the operation and at 1 year and 2 years after the surgery, respectively. The endoscopic finding showed that reflux esophagitis occurred in $7.1\%$ of the patients in the JI group and in $3.5\%$ in the RY group. Conclusion: We think that from the view point of quality of life, a jejunal interposition, as well as a Roux-en-Y procedure, is a useful reconstruction methods for a total gastrectomy.

• Nuclear Engineering and Technology
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• v.53 no.12
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• pp.4137-4141
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• 2021

As NPPs continue to operate, liquid waste continues to be generated, and containers are needed to store and transport them at low cost and high capacity. To transport and store liquid phase very low-level radioactive waste (VLLW), a container is designed by considering related regulations. The design was constructed based on the existing container design, which easily transports and stores liquid waste. The radiation shielding calculation was performed according to the composition change of barium sulfate (BaSO₄) using the Monte Carlo N-Particle (MCNP) code. High-density polyethylene (HDPE) without mixing the additional BaSO₄, represented the maximum dose of 1.03 mSv/hr (<2 mSv/hr) and 0.048 mSv/hr (<0.1 mSv/hr) at the surface of the inner container and at 2 m away from the surface, respectively, for a 10 Bq/g of ⁶⁰Co source. It was confirmed that the dose from the inner container with the VLLW content satisfied the domestic dose standard both on the surface of the container and 2 m from the surface. Although it satisfies the dose standard without adding BaSO₄, a shielding material, the inner container was designed with BaSO₄ added to increase radiation safety.

• Journal of Electrochemical Science and Technology
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• v.9 no.4
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• pp.276-281
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• 2018

High concentration of copper in mezcal, a representative Mexican spirituous alcoholic beverage, is a serious problem due to the damage that it may cause to human health. A cyclic voltammetry and square wave anodic stripping voltammetry study of copper (II) in three commercial mezcal samples based on glassy carbon electrode response was undertaken. The analysis was developed using a simulated matrix solution ($EtOH/H_2O$ (1:1), 0.1 M $LiClO_4$ and AcOH/AcONa 0.05 M/0.008 M), with Cu (II) concentrations in the range 0 - 1 ppm. Direct electrochemical analysis of mezcal samples was complicated by the presence of different organic compounds in the matrix. The analytical signal of Cu (II) in the spirituous was notably improved and the interferences caused by organic compounds were minimized, by diluting the mezcal samples 10% with $EtOH/H_2O$ (1:1) solution. An efficient quantification of Cu (II) was obtained from the calibration curve by the SWASV and using the internal standard method (Cd (II)) in commercial samples (1.2-6.7 ppm); the results were correlated satisfactorily with the values obtained by AAS.