• Title/Summary/Keyword: Hatch rate

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Effects of Silver Nanoparticles Exposed in Somite Stage on Zebrafish Development (Somite stage에 노출된 은나노 입자가 zebrafish 발생에 미치는 영향)

  • Hong, Suk-Ho;Song, Hyung-Gwi;Jeong, Kyeong-Jun;Ko, Kwang-Il;Yeo, Min-Kyeong
    • Environmental Analysis Health and Toxicology
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    • v.24 no.1
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    • pp.17-23
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    • 2009
  • Nanotechnology, one of the technologies that forms the core of the recent scientific innovation, is used much in our real lives. Especially products that use nano silver are being sold, with its positive characteristics resulting from the antibacterial effects of both nano materials and silver. But critiques have pointed out that nano silver diffused into everyday life too quickly as we do not have done any comprehensive research about the material, and worry that nano silver will affect the ecology adversely. Therefore, this research focuses on investigating the toxicity of silver nanoparticles first. To compare the effects of exposure to silver nanoparticles at pre-somite stage and somite stage(10 hours after fertilization), we exposed zebrafish embryos to silver nanoparticles(15, 30 ppt) during embryogenesis, and then checked the details of catalase enzyme activity. The hatch rate decreased in the silver nanoparticles exposed groups(15 and 30 ppt); furthermore, the hatched fishes had an abnormal notochord, damaged eyes and curved tail. The catalase activities of the 15 ppt exposed group at somite stage increased relative to those in the control group. Therefore, the silver nanoparticles could seriously damage the development of zebrafish embryos. Especially, exposure to silver nanoparticles at somite stage did severer damage than exposure since pre-somite stage did.

Comparative Toxicity of Abmectin to the Spider Mites, Tetranychus urticae Koch and Teranychus Kanzawai Kishida (Acarina; Tetranychidae) and the Predatory Mite, Amblyseius womersleyi Schicha (Acarina: Phytoseiidae) (점박이응애(Tetranychus urticae), 간자와응애(Tetranychus Kanzawai)와 긴털이리응애(Amblyseius womersleyi)에 대한 Abamectin의 독성 비교)

  • 김상수;백채훈
    • Korean journal of applied entomology
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    • v.35 no.2
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    • pp.164-172
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    • 1996
  • The comparative toxicity of abamectin to the predatory mite, Amblyseius womersleyi Schicha and the spider mites, Tetranychus urticae Koch and T. kanzawai Kishida was evaluated by leaf disc method. Abamectin was much less toxic to A. womersleyi than to the spider mites. Although survival rate of adult females of A. womersleyi tended to decrease with increasing abamectin concentration, 8-78% of predators remained alive at concentrations of 0.38-6 ppm. Likewise, reproduction was significantly reduced with increasing abamectin concentration. Abamectin neither affect the hatch of A. womersleyi eggs nor the development of surviving immature predators. Survival of immature predators decreased with increasing abamectin concentration. However, 42-90% of immature predators reached adulthood at 0.38-3 ppm. Adult female predators survived on a diet of spider mites intoxicated with abamectin, although their fecundity and the sex-ratio of the progeny were significantly affected. Abamectin at selective sublethal concentrations (0.38-0.75 ppm) could he of value in adjusting predatorlprey ratios in integrated management of T. urticae and T. kanzawai.

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Reproduction Study of Korean Endemic Species Acheilognathus koreensis (고유종 칼납자루의 재생산 기초 연구)

  • Kim, Chi-Hong;Lee, Wan-Ok;Lee, Jong-Ha;Beak, Jae-Min
    • Korean Journal of Ichthyology
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    • v.23 no.2
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    • pp.150-157
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    • 2011
  • In this study we described reproduction study of Korean endemic species, Acheilognathus koreensis and three other acheilognathinae species A. signifer, Rhodeus pseudosericeus, and R. uyekii. Morphology of egg shape and larvae just hatched is unique by the species respectively. There is no interrelation factor between size of female and number of spawned eggs per one time. Minium water temperature for spawning of A. koreensis was observed in $13.0^{\circ}C$ having low hatching rate with 43.5 percent. The egg of A. koreensis began to hatch approximately 79 hours after insemination. As higher as water temperature until $22.0^{\circ}C$ hatching elapsed time for developing eggs of A. koreensis and three species in this study was shortened. A. koreensis was grew up to be a adult enough which can be join to new production for three hundred days after hatching with 52.4 mm in total length. This reproduction study will be applied to preservation of Korean endemic fresh water fishes basically.

The Effects of Assisted Hatching (AH) According to the Indications (적응 요인에 따른 보조부화술 (Assited Hatching, AH)의 효과)

  • Kim, J.S.;Kang, S.H.;Kwon, Y.J.;Son, I.P.;Choi, K.W.;Kim, S.K.;Chun, H.S.;Lee, J.G.;Lee, S.J.;Park, J.M.
    • Clinical and Experimental Reproductive Medicine
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    • v.25 no.2
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    • pp.123-128
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    • 1998
  • Implantation rates remain low following human in vitro fertilization (IVF). Suboptimal culture conditions may limit the ability of embryos to hatch as blastocysts, and artificial opening of the zona pellucida has been proposed as a means to promote subsequent hatching (assisted hatching). In this study, assisted hatching (AH) by zona drilling using acidic Tyrode's solution was performed in 320 patients, due to their age of more than 38 years (group A), the thick zona pellucida (group Z; $ZP\geq0.18{\mu}m$), and failures in implantation more than 3 times in previous IVF-ET trial (group P). This study was designed firstly, to study the effects of AH on the outcomes of IVF-ET according to the indications and secondly, to verify the appropriate application of AH. The results were as follows; 1. There was no difference in pregnancy rate between AH group (26.6%) and non-AH group (26.5%). 2. Assisted hatching (AH) showed significantly higher pregnancy rate of the patients with thick zona pellucid a than those of the patients with age factor and with the history of repeated implantation failure. But in the patients with age factor only, AH resulted in higher pregnancy rate. 3. Interestingly, the patients with complex factors including zona factor (Z: 33.9%; ZA: 30.4%; ZP: 31.6%; ZAP: 21.4%) showed higher pregnancy rates than other complex factors excluding zona factor (A: 24.4%, P: 0%; AP: 10.8%). From these results, AH is more helpful to the patients with thick zona pellucida rather than patients with older age and/or previous repeated implantation failure.

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An Ethanol Extract of the Brown Seaweed Hizikia fusiformis and Its Active Constituent, Fucosterol, Extend the Lifespan of the Nematode Caenorhabditis elegans (갈조류 톳(Hizikia fusiformis)의 에탄올추출물 및 이의 활성성분 fucosterol에 의한 예쁜꼬마 선충의 수명 연장)

  • Oktaviani, Diyah Fatimah;Bae, Young-Seuk;Meinita, Maria Dyah Nur;Moon, Il Soo;Hong, Yong-Ki
    • Journal of Life Science
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    • v.29 no.10
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    • pp.1120-1125
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    • 2019
  • The short-lived nematode Caenorhabditis elegans has been used as a model organism for many studies, including lifespan extension. To screen common seaweeds for natural anti-aging agents, the lifespan of C. elegans (N2 wild-type strain) was measured by its hatch rate, growth rate, survival rate, chemotaxis, brood size, and egg-laying time after exposure to nematode growth medium (NGM) containing seaweed extracts. Approximately 30 animals synchronized at the first larval stage were incubated until they reached their adult stages before laying their eggs and were transferred to fresh NGM every 3 days. We also identified the major active compound from the seaweed by gas chromatography-mass spectrometry and tested its optimal dose for longevity. Of 13 common seaweed species, an ethanol extract of the brown seaweed Hizikia fusiformis showed the greatest effect on hatching, growth, and survival rates. The lifespan of C. elegans was significantly expanded 1.54-fold and 1.23-fold in the presence of the ethanol extract (0.05 mg/ml) and the main active component, fucosterol (0.05 mg/ml), respectively. Exposure to the ethanol extract also increased chemotaxis 1.13-fold, decreased brood size 0.74-fold, and shortened egg-laying time 0.96-fold. These results suggest that the aquaculturable H. fusiformis may be a promising source of a diet supplement to support health care.

Insecticidal Activities and Synergism of Bistrifluron Against EPN-Resistant Strain of Diamondback Moth, Plutella xylostella (Lepidoptera: Plutellidae) (EPN 저항성 배추좀나방에 대한 IGR계 약제 Bistrifluron의 살충활성과 세 가지 협력제에 의한 살충활성 증진 효과)

  • Joo, You-Lee;Yang, Jeong-Oh;Yoon, Chang-Mann;Kim, Gil-Hah
    • The Korean Journal of Pesticide Science
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    • v.13 no.1
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    • pp.54-61
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    • 2009
  • EPN-resistant diamondback moth were tested the developmental characteristics, longevity, fecundity and synergistic effect with synergists when treated with the bistrifluron, an inhibitor of chitin synthesis. Inhibition rate of egg hatch was below at the recommended concentration (50 ppm) to the EPN-resistant strain than EPN-non selected strain, however, mortality within 24hr after hatching was showed as 50-60%. They did not show the difference between two strains. Mortality of larval instars were showed effective to two strains with no difference. Inhibition rate of emergence did not show any effect when treated with pupae. Moreover, they did not affect to the longevity and fecundity. When bistrifluron was treated at 50 ppm to the adult, however, longevity and fecundity was decreased with no difference between two strains. Bistrifluron to the EPN-resistant strain showed synergistic effect as high as 137.7 and 73.1 folds with synergist such as PBO (microsomal oxidase inhibitor) and polyoxin B (chitin synthetase inhibitor), respectively.

Effects of Acidification on the Species Compositions of Heterotrophic Bacterial Community in Microcosm (수계 종속영양세균 군집의 종조성에 미치는 산성화의 영향)

  • 안영범;조홍범;최영길
    • Korean Journal of Microbiology
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    • v.33 no.3
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    • pp.175-180
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    • 1997
  • In an artificial pH-gradient hatch culture system, the author analyzed the effects of acidification on the species composition of heterotrophic bacteria. As the result of this study, it was found that the numbers of total bacteria were not affected by acidification and that the population size of heterotrophic bacteria decreased as pH became lower. The heterotrophic bacteria isolated from all of the pH gradient were 12 genera and 22 species. and among them, gram negative and gram positive bacteria were 64% and 36%, respectivcly. As pH decreased, the distribution rate of gram negative bacteria increased while that of gram positive bacteria decreased. Regarding to distrihution rate of genuses in each pH gradient, 13 genuses appeared at pH 7 while only 5 genuses appeared at pH 3. which means that the diversity of genera decrease as pH decreased. As a result of cluster analysis, diversity indices 01 species had ranges from 1.13 to 2.37, and decreased as pH decreased. In order to evaluate the diversity of different size samples, we analyzed the expected number of species appearance according to pH by rarefaction method. The statistical significance of species diversity was verified by the fact that the number decreased at lower pH.

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Insecticidal activity of Diamondback Moth, Plutella xylostella against Bacillus thuringiensis and Neem oil (Bacillus thuringiensis와 Neem oil에 대한 배추좀나방의 살충활성)

  • Cho, Min-Su;Choi, Su-Yeon;Kim, Tae-Whan;Park, Chan;Kim, Dam-A;Kim, Young-Rim;Oh, Se-Mun;Kim, Sung-Woo;Youn, Young-Nam;Yu, Yong-Man
    • The Korean Journal of Pesticide Science
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    • v.13 no.4
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    • pp.315-324
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    • 2009
  • For the environmental friendly management of diamondback moth, Plutella xylostella (L.), Bacillus thuringiensis subsp. kurstaki ($30{\times}10^8\;cfu/mg$) and neem oil (0.5% azadirachtin) were used as green control agencies with mixed and alternative treatments on the chinese cabbage. When Bacillus thuringiensis subsp. kurstaki was applied to 1st and 2nd larva of P. xylostella with recommended concentration, their mortalities were reached to 100% by 2 days after treatment. In case of azadirachtin, its effect of mortality was continued for 7 days, and reached to 100% mortality. $LC_{50}$ values of Bacillus thuringiensis subsp. kurstaki and azadirachtin against 1st, 2nd, 3rd and 4th larva of P. xylostella were $2.8{\times}10^4$, $3.1{\times}10^4$, $3.4{\times}10^4$ and $1.5{\times}10^5\;cfu/ml$, and 2.7, 3.9, 4.7 and 7.1 ppm, respectively. The number of laid eggs of P. xylostella was reduced to 57.5 at 25 ppm of azadirachtin compared with control treatment. The hatch ratio was not significantly different with Bacillus thuringiensis subsp. kurstaki treatment in comparison with control treatment. However, when azadirachtin was applied, their hatch ratio were reduced to 25.8 and 45.4% at 25 and 50 ppm, respectively. On the other hand, emergence rate of eggs was not different with Bacillus thuringiensis subsp. kurstaki treatment, but 45.4% was shown in azadirachtin treatment with 50 ppm in comparison with control. When the mixture with Bacillus thuringiensis subsp. kurstaki and azadirachtin was applied to adults of P. xylostella, their mortality was higher than Bacillus thuringiensis subsp. kurstaki treatment only. These results are supposed that the mixture of Bacillus thuringiensis subsp. kurstaki and azadirachtin might be used as green control agents for reducing the demage of diamondback moth in the Chinse cabbage.

Influence of Temperature on the Egg Production and Hatching of Microcotyle sebastis (Monogenea : Microcotylidae), Parasitic on Rockfish, Sebastes schlegeli (수온이 조피볼락에 기생하는 아가미흡충(Microcotyle sebastis)의 산란과 부화에 미치는 영향)

  • Kim, Ki-Hong;Choi, Eun-Seok;Cho, Jae-Bum;Hwang, Yoon-Jung;Park, Soo-Il
    • Journal of fish pathology
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    • v.11 no.2
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    • pp.113-117
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    • 1998
  • The influence of temperature on the rate of egg production and embryonic development of Microcotyle sebastis was investigated to determine the precise time of a second treatment. The survival time of the adults of M. sebastis was inversely proportional to temperature. The number of laid eggs per each replicate during the first 24 h was $39.3{\pm}4.0$ at $10^{\circ}C$, $62.7{\pm}14.2$ at $15^{\circ}C$, $101.0{\pm}5.6$ at $20^{\circ}C$ and $89.0{\pm}11.0$ at $25^{\circ}C$. The time required for egg hatching of M. sebastis was $31.30{\pm}4.88$, $17.52{\pm}3.24$, $11.59{\pm}3.02$ and $10.76{\pm}3.10$ days at 10, 15, 20 and $25^{\circ}C$, respectively. The regression models of the time required for the beginning and 50% point of hatching according to the different temperatures were as follows; Beginning of hatch: D=58.2000-$4.2067{\times}Temp+0.0867{\times}(Temp)^2$ ($P\leq0.01$), 50% of hatch: D=91.3833-$7.5767{\times}Temp+0.1767{\times}(Temp)^2$ ($P\leq0.01$).

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Study on Hospital Environmental Causes Affected the Mother′s Comfort After Her Child Birth (산욕부 안위에 영향을 미치는 병원환경 요인에 관한 연구)

  • 변수자
    • Journal of Korean Academy of Nursing
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    • v.8 no.1
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    • pp.1-15
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    • 1978
  • The Purpose of this study is to examine closely the causes influenced upon the comfort and recovery of the woman delivered of a child in the hospital at the same time to understand environmental status of hospitals in order to promote mother's health recovery, and to improve hospital environment by emphasizing the meaning of environment and health before the medical staff and hospital administrative authority. In the method of servery of the research, 165 post paestum patients have been randomly selected who were accommodated and delivered their babies at OB(obstetric ) & GY (Gynecologic) unit the 7 general hospitals for the period of 6 December 1976 through 17 December 1976. As for the survey, it has been used of Questionnaire where we have 65 items in the respect of personal environment in the hospital such as trusting nurse, ability, reliability, kindness and etiquette of nurse and tile character of nurse the relationship with patients the other respect of physical environment included 9f temperature, moisture. air-ventilation lightening noise, cleanness. facilities, and the third realm being of mother's hearth ground to have the following conclusion 1. The feature of the collected personnel they are from OB or GY sects of from OB unit of the other 5 hospitals except the two general hospitals of the college or school Otherwise the rate of the patients to nurses would be 9 : 1. As for the nurses'ground it would be appeared of 20-25 years of age as the 76%. either 3 year course or 4 year course in the education would be each 50% and less than 2 year experience case would record as of 60 %. In the respect of hospital physical environmental status, there we have two hospitals without any thermometers, on the other han4 nowhere there's hygrometer, otherwise, the lightening is normal or over than normal As for the structure of noise protection the corridors're, generally speaking worse than rooms, nerver hueless, there's no ventilating system in the hospitals. The rooms'repainted in white and yellow, light green white, or green color. The patient's clothing were in green pink blue, light green or in white co for. There're not anything special in both decoration and equipments. Most of them used tall beds except in one hospital 2. To the extent of perception of patient's hatch 9round and hospital environment it is presented that they perceived nurse's ability in highest in total human variable, though perceived kindness or etiquette in the lowest otherwise, comparatively high in total average. 3. In the respect of physical environment it is highest perceived of lightening terms, otherwise, lowest perceived of air ventilation and total average became lowest than the one of the original record 4. To ages, in the respect of hatch ground rather old aged mother than the younger one has perceived that nurse would be trusting, in good service character, able, at the same time, liable, Otherwise, in physical environment regardless of age, they perceived lightening in high and remarkably lower in ventilation As a result of the examination of the difference in hospital environment to each age it is appeared of statistical difference at 5% level of ability in the personal environment otherwise little difference as for physical environment 5. In the respect of perceiving level to educational standard it is highly perceived of personal environment for higher ranking group rather than lower group in the educational standard. In case of physical environment it is highly perceived for lower level group rather than higher level group in educational background. The variables which have statistical significance at 5% level are from trusting kindness, etiquette and total kindness, etiquette and total all significance at 5% level are from trusting, kindness, etiquette and total human environment variable in personal environment, otherwise, there's little difference in the physical environment. 6. The perceiving level due to times of admission and accommodation at the hospital would be cleared out as gradual higher perception both physical and personal environment in the hospital. At 5% significant level of the ventilation condition in physical environmental variable it is presented of meaningful difference otherwise, there we have little difference both in Personal variable and other one. 7. In accordance with living standard, the perception degree of personal environment in tee hospital would be inclined to increase to higher living standard on the other hand, in case of the physical environment, the perception level world increase to lower living standard At 5 % level, the trustuariable and total scores in the personal eicuironmectal variable there appeared a meaningful/ significant difference otherwise, there presented little difference both in physical environmental and other variable to the living standard 8. Pertaining to family unit, the mother of an independent family unit perceived highly in all respect of the personal and the physical environment in the hospital rather than the woman of succeeding family unit. At 5 % level there appeared a difference in the respect of kindness and etiquette both in personal environment variable, on the other hand, there hardly marked a difference between other variable and physical environmental one. 9. The degree of perception to comforting level has little connection with a statistical difference the age, educational level hospital admitting times, living standard or family unit. 10. The most effective variable to mother's comforting level will be nurse's ability, reliability, trusting manner, and total physical environment variable in order.

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