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Characteristics and Toxicity Sensitivity of Korean Dominant Species Daphnia galeata for Ecotoxicity Testing: Comparative Study with Daphnia magna (생태독성실험을 위한 한국 우점종 유리물벼룩(Daphnia galeata)의 특성 및 독성민감도: 큰물벼룩(Daphnia magna)과의 비교연구)

  • Cui, Rongxue;Kwak, Jin Il;An, Youn-Joo
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.4
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    • pp.193-200
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    • 2016
  • Water flea is a widely used test species in the aquatic ecotoxicity test. In Korea, D. magna is currently used as a standard test species, however that do not inhabit in the Korean aquatic ecosystem. In this study, Daphnia galeata, which is a dominant species in the Korean aquatic ecosystem, was collected from domestic lake and investigated to suggest the D. galeata for ecotoxicity assessment in Korea. We investigated the characteristics, life span, and toxicity sensitivity compared with D. magna. The life span test of D. galeata was performed in this study, and then the results were compared to the sensitivity with D. magna to confirm the applicability for ecotoxicity assessment. The 48h-L(E)C50 values for seven heavy metals (As, Cd, Cr, Cu, Hg, Ni, and Zn) of D. galeata and D. magna were collected and analyzed. As a results, shorter lifetime, less reproduction, smaller body size of D. galeata were observed compared with D. magna. D. galeata was similar or more sensitive than D. magna for seven heavy metals. Therefore, we propose that D. galeata is a suitable test species for ecotoxicity testing in Korea.

Effects of Gonadotrophins on In Vitro Growth and Maturation of Mouse Preantral Follicles (생쥐 Preantral Follicles의 체외성장 및 성숙에 있어서 Gonadotrophins의 역할)

  • 김동훈;지희준;강희규;한성원;이훈택;정길생;이호준
    • Korean Journal of Animal Reproduction
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    • v.23 no.1
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    • pp.53-61
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    • 1999
  • The present study was designed to investigate the effects of gonadotrophins on in vitro growth and maturation in mouse preantral follicles. Ovaries were removed from 12-day-old ICR mice. Follicles were dissociated enzymetically in Leibovitz L-15 medium containing 1 mg/$m\ell$ collagenase and 0.2 mg/$m\ell$ DNase I. The follicles were cultured on Transwell-COL membrane inserts in six well cluster dishes for 10 days. The culture medium was $\alpha$MEM medium supplemented with 5% fetal bovine serum and FSH or HMG. After 10 days of growth in vitro, follicles were allowed to mature for 18~20 hr in medium supplemented with 1.5 IU/$m\ell$ hCG. The oocytes were then denuded of their cumulus cells and assessed maturation status. Concentrations of oestradiol and progesterone were measured with a radioimmunoassay. Oocyte diameter was determined with an ocular micrometer. The survival and Metaphase II rates of oocytes were significantly higher in FSH treatment groups than in control group (P<0.001), but there were no differences among the groups of treated FSH concentration. The survival and Metaphase II rates of oocytes in HMG treatment group (60.9 and 40.6%) were higher than in FSH treatment group (76.6 and 48.2%) and control group (49.2 and 7.1%). The survival and Metaphase II rates of oocytes on both FSH and LH treatment groups were no differences among the ratios of FSH and LH. Diameter of oocyte was no differences among the treatment groups, but smaller than compared to in vivo grown oocyte. Through the entire culture period, secretions of oestradiol and progesterone were significantly less in control group than in HMG and FSH treatment groups. These results suggest that gonadotrophins playa key role in in vitro culture of mouse preantral follicles. Especially, addition of FSH and LH should be more effective than FSH alone.

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Studies on the Selenium Type and Metabolism of Selenium Accumulation in the Selenium-Enriched Mushroom, Flammulina Velutipes, and Its Spent Mushroom Composts (셀레늄 강화 팽이버섯과 폐배지의 셀레늄 형태 및 팽이버섯내 셀레늄 축적대사에 관한 연구)

  • Lee, S.H.;Kwak, W.S.;Kim, W.Y.
    • Journal of Animal Science and Technology
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    • v.47 no.2
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    • pp.305-316
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    • 2005
  • This study was conducted to determine the total amount and type of seleniwn (Se) in the Se-enriched mushroom and its spent mushroom composts (SMC), and to investigate the metabolism in relation to Se accwnulation in the mushroom. Mushrooms, Flammulina velutipes, used in this study were grown for 60 days by adding 2 rng of inorganic Se (Na2Se03) per kg of mushroom composts (MC) on as-fed basis and were compared with normal mushrooms grown on the non Se-supplemented Me. Total Se contents for Se-treated mushrooms were significantly increased (P < 0.0001) by 20-fold (4.51 $\mu$/ g of dry) compared to Se-untreated (0.23 $\mu$/ g of dry). On the contrary, organic Se ratio was significantly lower (P < 0.0001) in the Se-treated mushroom (72.3 %) than the Se-untreated one (100 %, not analytically detected of inorganic Se). Se distribution upon a length in the Se-treated mushrooms was the highest in the bottom part (6.86 $\mu$/ g of dry) near to MC, and top and middle parts were significantly lower (3.71 and 3.01 $\mu$/ g of dry, respectively; P < 0.001) than the bottom. In the SMC from Se-treated mushrooms, the significant amount of Se (5.04l1g/g of dry) was remained, but that from the Se-untreated mushrooms was significantly low (P$\mu$ / g of dry. Se-treated SMC showed a high ratio of organic Se (65.67 %), suggesting that the significant amount of inorganic Se in the SMC was converted to organic Se by mushroom mycelia. Prior to mycelia inoculation in the mushroom culture, the sterilization of MC brought approximately 18% of Se loss in the MC. Apparent and net accumulation rates (%) for Se into mushrooms were 14.81 and 10.14 %, respectively, resulting from the Se volatilization into the air via metabolic process of mushroom itself. The result of this study shows that inorganic Se addition to MC for mushroom improved the organic Se contents in the mushroom and SMC. This study showed the possibility that Se in Se-enriched mushroom and SMC could be utilized as Se sources of food for human as well as feed for livestock.

Analysis of SNPs in Bovine CSRP3, APOBEC2 and Caveolin Gene Family (소의 CSRP3, APOBEC2, Caveolin 유전자들의 단일염기다형 분석)

  • Bhuiyan, M.S.A.;Yu, S.L.;Kim, K.S.;Yoon, D.;Park, E.W.;Jeon, J.T.;Lee, J.H.
    • Journal of Animal Science and Technology
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    • v.49 no.6
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    • pp.719-728
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    • 2007
  • The cysteine and glycine rich protein 3 (CSRP3), apolipoprotein B mRNA editing enzyme catalytic polypeptide‐like 2(APOBEC2) and caveolin (CAV) gene family(CAV1, CAV2, CAV3) have been reported to play important roles for carcass and meat quality traits in pig, mouse, human and cattle. As an initial step, we investigated SNPs in these 5 genes among eight different cattle breeds. Eighteen primer pairs were designed from bovine sequence data of NCBI database to amplify the partial gene fragments. Sequencing results revealed 9 SNPs in the coding regions of three caveolin genes, 1 SNP in CSRP3 and 3 SNPs in APOBEC2 gene. All the identified SNPs were confirmed by PCR-RFLP. Also, 9 more intronic SNPs were detected in these genes. However, all identified mutations in the coding region do not change amino acid sequence. Allelic distributions were significantly different for 5 SNPs in CAV2, CAV3, CSRP3 and APOBEC2 genes among the eight different breeds. These results gave some clues about the polymorphisms of these genes among the cattle breeds and will be useful for further searches for identifying association between these SNPs and meat quality traits in cattle.

Addition of Capsicum oleoresin, Carvacrol, Cinnamaldehyde and their mixtures to the broiler diet II: Effects on meat quality

  • Ipcak, Hasan Huseyin;Alcicek, Ahmet
    • Journal of Animal Science and Technology
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    • v.60 no.4
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    • pp.9.1-9.11
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    • 2018
  • Background: In recent years, with the prohibition of antibiotics used as growth stimulants in the nutrition of farm animals, researchers have searched for alternative natural and reliable products in order to be able to sustain the developments experienced during the use of antibiotics and to overcome the possible inconveniences. In this context, studies on evaluation of essential oils in poultry nutrition have been reported to improve the utilization of feed, stimulate the release of digestive enzymes, increase absorption in the stomach and intestines, antimicrobial and anti-parasitic effects and thus, can be an alternative to antibiotics and improve meat quality as well. Indeed, this study has been carried out to explore the effects of the addition of 150 mg/kg capsicum oleoresin (CAP), carvacrol (CAR), cinnamaldehyde (CIN) or their mixture (CAP+CAR+CIN) into the broilers' ration over sensory, physical and chemical properties in breast meat and leg meat. Methods: Experiments were conducted over 400 male and female broiler chicks (Ross-308) in 5 groups (1 control group and 4 treatment groups), each composed of 80 chicks. The control group was fed without feed additives while the second, third, fourth and the fifth groups were fed with 150 mg CAP/kg feed, 150 mg CAR/kg feed, 150 mg CIN/kg feed, and 150 mg CAP+CAR+CIN/kg feed, respectively. Results: Addition of CAP, CAR, CIN or CAP+CAR+CIN had effects on the sensory (of taste, tenderness, juiciness and overall acceptability); physical properties (of $L^*$ value and toughness), the chemical properties (of DM, CF, CP, linoleic, EPA, behenic, MUFA, PUFA and ${\Sigma}n-6$ of the leg meat), the physical characteristics (of toughness and firmness), and the chemical properties (of CF, CP, linoleic, ecosenic, EPA, lignoseric, MUFA and ${\Sigma}n-3$) of the breast meat in comparison to control group. Furthermore, while the treatments had positive impacts on thawing loss, cooking loss and water holding capacity in both breast and leg meat; no effect was observed on pH value and lipid oxidation on day 1, day 4 and day 8. Conclusion: The results strongly suggested that the addition of CAP, CAR, CIN or CAP+CAR+CIN to the rations of the broiler chicks changed the sensory, physical and chemical properties of breast and leg meat. It was also observed that these compounds were more effective when they were added to the ratio as a mixture rather than adding them individually.

Gluconacetobacter persimmonis sp. nov., Isolated from Korean Traditional Persimmon Vinegar

  • Yeo, Soo-Hwan;Lee, Oh-Seuk;Lee, In-Seon;Kim, Hyun-Soo;Yu, Tae-Shick;Jeong, Yong-Jin
    • Journal of Microbiology and Biotechnology
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    • v.14 no.2
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    • pp.276-283
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    • 2004
  • Screening was performed to isolate cellulose-producing microorganisms from the Korean traditional fermented persimmon vinegar. The resulting strain, KJ $145^{T}$, was then taxonomically investigated by phenotypic characterization, particularly chemotaxonomic, and by phylogenetic inference based on a 16S rDNA sequence analysis including other related taxa. Strain KJ $145^{T}$ was found to grow rapidly and form pale white colonies with smooth to rough surfaces on a GYC agar. Strain KJ $145^T$ also produced acetate from ethanol, and was tolerable to 10% ethanol in SM medium. In a static culture, a thick cellulose pellicle was produced, and in GYC broth, the strain grew at temperatures ranging from 28 to $40^\circ{C}$ with an optimum pH of 4.0. The genomic DNA G+C content of strain KJ $145^T$ was 61.9 mol%, and the predominant ubiquinone was Q 10 as the major quinone and Q9 as the minor quinone. The major cellular fatty acids were $C_{16:0}$ and the sum in feature 7 ($C_{18:1}$ w9c, w12t and/or w7c). A 16S rRNA-targeted oligonucleotide probe specific for strain KJ $145^T$was constructed, and the phylogenetic position of the new species was derived from a 16S rDNA-based tree. When comparing the 16S rDNA nucleotide sequences, strain KJ $145^T$ was found to be most closely related to G. hansenii LMG $1527^T$ (99.2%), although KJ $145^T$ was still distinct from G. hansenii LMG $l527^T$ and G. xylinus LMG $1515^T$ in certain phenotypic characteristics. Therefore, on the basis of 16S rDNA sequences and taxonomic characteristics, it is proposed that strain KJ $145^T$ should be placed in the genus Gluconacetobacter as a new species, Gluconacetobacter persimmonis sp. nov., under the type-strain KJ $145^T$ (=KCTC =$10175BP^T$=KCCM=$10354^T$).

Heavy Metal Removal Efficiency in Accordance with Changes in Acid Concentrations in a Micro-nano Bubble Soil Washing System and Pickling Process (마이크로나노버블 토양세척시스템 및 산세척 복합공정의 산 농도변화에 따른 중금속 제거효율에 관한 연구)

  • Jung, Jin-Hee;Choi, Ho-Eun;Jung, Byung-Gil;Sung, Nak-Chang;Yi, Gi-Chul;Choi, Young-Ik
    • Journal of Environmental Science International
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    • v.26 no.1
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    • pp.23-28
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    • 2017
  • This study was aimed at determining the changes in heavy metal removal efficiency at different acid concentrations in a micro-nanobubble soil washing system and pickling process that is used to dispose of heavy metals. For this purpose, the initial and final heavy metal concentrations were measured to calculate the heavy metal removal efficiency 5, 10, 20, 30, 60, and 120 min into the experiment. Soil contaminated by heavy metals and extracted from 0~15 cm below the surface of a vehicle junkyard in the city of U was used in the experiment. The extracted soil was air-dried for 24 h, after which a No. 10 (2 mm) was used as a filter to remove large particles and other substances from the soil as well as to even out the samples. As for the operating conditions, the air inflow rate in the micro-nano bubble soil washing system was fixed at 2 L/min,; with the concentration of hydrogen peroxide being adjusted to 5%, 10%, or 15%. The treatment lasted 120 min. The results showed that when the concentration of hydrogen peroxide was 5%, the efficiency of Zn removal was 27.4%, whereas those of Ni and Pb were 28.7% and 22.8%, respectively. When the concentration of hydrogen peroxide was 10%, the efficiency of Zn removal was 38.7%, whereas those of Ni and Pb were 42.6% and 28.6%, respectively. When the concentration of hydrogen peroxide was 15%, the efficiency of Zn removal was 49.7%, whereas those of Ni and Pb were 57.1% and 42.6%, respectively. Therefore, the efficiency of removal of all three heavy metals was the highest when the hydrogen peroxide concentration was 15%.

THE EFFECT OF DIETARY PROTEIN AND ALUM IN LITTER ON PERFORMANCE, NH3 GAS CONCENTRATION AND LITTER COMPOSITION IN BROILER

  • 남기홍
    • Proceedings of the Korea Society of Poultry Science Conference
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    • 2001.11a
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    • pp.86-88
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    • 2001
  • An experiment was conducted to determine how broiler performance, feces and litter concentration of N can be maintained and whether NH3 gas concentration can be reduced with reducing dietary CP, adding ALUM(AL2(SO4)3.14H20) in litter and supplementing with amino acid and vitamin D in feed. The experiment was divided into a starter period(1 to 21d) and grower period(22 to 42d), each having three different CP with 90 birds per treatment of 3 replications. The CP treatments consisted of a mean CP of 23.0(control 71), 20.4 (72) and 18.0 (73) % for starter and 21.0(control 71),19.3 (72) and 17.0 (73) % for grower, respectively, but with similar amino acid levels as the control. Alum was mixed in each treatment except control treatment with 200g in kilogram litter(rice bran) weight. Results suggested that reducing CP below control in the diets fed during 3wks and 6wks slightly increased feed gain and slightly decreased feed intake and weight gain. However, there were no significant difference among treatments. Reducing CP caused NH3 gas concentration to decline by 74.8 - 80.9% when Alum was mixed in litter(P < 0.05). Litter N concentration did not show any difference(P > 0.05) among treatments. These results suggest that dietary manipulation with adding Alum in litter show for significant reducing NH3 gas concentration while maintaining acceptable Production performance from broiler.

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Overview of UV-B Effects on Marine Algae (자외선이 해조류에 미치는 영향에 관한 고찰)

  • 한태준
    • Korean Journal of Environmental Biology
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    • v.17 no.1
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    • pp.1-9
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    • 1999
  • Numerous observations revealed strong evidence of increased middle ultraviolet radiation or UV-B (280 ~ 320 nm) at the earth's surface resulting from stratospheric ozone depletion. UV is the waveband of electromagnetic radiation which is strongly absorbed by nucleic acids and proteins, thus causing damage to living systems. It has been recorded in the East Sea, Korea that solar UV-B impinging on the ocean surface penetrates seawater to significant depths. Recent researches showed that exposure to UV-B for as short as 2h at the ambient level (2.0 Wm$^{-2}$) decreased macroalgal growth and photosynthesis and destroyed photosynthetic pigments. These may suggest that UV-B could be an important environmental factor to determine algal survival and distribution. Some adaptive mechanisms to protect macroalgae from UV-damage have been found, which include photoreactivation and formation of UV-absorbing pigments. Post-illumination of visible light mitigated UV-induced damage in laminarian young sporophytes with blue the most effective waveband. The existence of UV-B absorbing pigments has been recognized in the green alga, Ulva pertusa and the red alga, Pachymeniopsis sp., which is likely to exert protective function for photosynthetic pigments inside the thalli from UV-damage. Further studies are however needed to confirm that these mechanisms are of general occurrence in seaweeds. Macroalgae together with phytoplankton are the primary producers to incorporate about 100 Gt of carbons per year, and provide half of the total biomass on the earth. UV-driven reduction in macroalgal biomass, if any, would therefore cause deleterious effects on marine ecosystem. The ultimate impacts of increasing UV-B flux due to ozone destruction are still unknown, but the impression from UV studies made so far seems to highlight the importance of setting up long-term monitoring system for us to be able to predict and detect the onset of large -scale deterioration in aquatic ecosystem.

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Stimulation of Blood Flow Needs a Parallel Magnetic Field and Psycho-physics acupuncture

  • Oh, Hung-Kuk
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2000.11a
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    • pp.105-112
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    • 2000
  • The conventional model did not take momentum conservation into consideration when the electron absorbs and emits the photons. II-ray provides momentum conservations on any directions of the entering photons, and also the electrons have radial momentum conservations and fully elastic bouncing between two atoms, in the new atom model. Conventional atom model must be criticized on the following four points. (1) Natural motions between positive and negative entities are not circular motions but linear going and returning ones, fur examples sexual motion, tidal motion, day and night etc. Because the radius of hydrogen atom's electron orbit is the order of 10$^{-11}$ m and the radia of the nucleons in the nucleus are the order of 10$^{-l4}$m and then the converging $\pi$-gamma rays to the nucleus have so great circular momentum, the electron can not have a circular motion. We can say without doubt that any elementary mass particle can have only linear motion, because of the $\pi$-rays' hindrances, near the nucleus. (2) Potential energy generation was neglected when electron changes its orbit from outer one to inner one. The h v is the kinetic energy of the photo-electron. The total energy difference between orbits comprises kinetic and potential energies. (3) The structure of the space must be taken into consideration because the properties of the electron do not change during the transition from outer orbit to inner one even though it produces photon. (4) Total energy conservation law applies to the energy flow between mind and matter because we daily experiences a interconnection between mind and body. Any magnet absorbs n-rays to S pole and sends out the $\pi$-rays from N pole. Proton are constructed with the closed n-rays quantum-mechanically. The crystallizing n-bonding makes two $\pi$-far infrared rays of one wave length between two protons if two $\pi$-rays are supplied to each proton. It is easily done for a $\pi$-ray to be absorbed to a proton if there is a parallel magnetic flow to the blood flow because a $\pi$-ray advances axially under a magnetic field and a proton looks like a sphere. A axially advancing disk-like $\pi$-ray can meet more easily the coming spheres than from the other directions. The blood crystals stimulate the autonomous nerves on the blood vessels during the flow by their mechanical sliding collisions. SM n-ray meridian therapy and SMACN $\pi$-ray meridian therapy show the stimulation of blood flow and also combinational experiment between SM $\pi$-ray meridian therapy and n-ray psycho-physics acupuncture shows more clearly that magnet is forcing to make $\pi$-rays absorbed to the nucleons.s.ons.

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