• 제목/요약/키워드: natural reaction

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Attribution of Cortical Granules to Formation of Fertilization Envelopes and Polyspermy Block in Urechis unicinctus

  • Shin, Kil-Sang;Kwon, Hyuk-Jae;Kim, Wan-Jong
    • Animal cells and systems
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    • 제9권2호
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    • pp.57-64
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    • 2005
  • Cortical reaction and polyspermy block are well defined in most marine invertebrates. In Urechis species, the function of cortical granules (CGs) is not yet known, and there is controversy on whether the cortical reaction occurs, or the fertilization envelope (FE) is attributed to CG releases or functions to prevent polyspermy. This study was carried out to determine the cortical reactions and functions of the FE in Urechis unicinctus. Artificial insemination of the eggs revealed that CG release occurred to give rise to perivitelline space (PS) into the final FE. Both PS and final FE effectively blocked polyspermy. The final FE was accomplished within 10 min after sperm-egg initial binding. No massive release of CGs occurred within the early phase of 5 min after the initial binding, initially and the PS seemed to playa role to prevent polyspermy. The CG massively released its content into the PS in late phase of FE formation, and differentiated PS into five intermediate layers. The layers opened into each other by anastomosis, so that the final FE consisted of two layers, the inner layer ($15{\mu}m$ in thickness) and the outer layer ($1{\mu}m$ in thickness). The outer layer derived from vitelline layer and the inner layer consisted of PS and CG secretions. Immunofluorescence and confocal laser microscopy revealed that the spermatozoon took up residence in the egg cortex during FE formation and successive meioses of the fertilized egg. These results suggest that both PS and final FE of U. unicinctus were equivalent to the early and late block, respectively, of other marine animals.

국산 천연 벤토나이트로부터 제올라이트 A의 합성 (Synthesis of Zeolite A from Natural Bentonite in Korea)

  • 심미자;김상욱
    • 한국재료학회지
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    • 제5권7호
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    • pp.897-902
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    • 1995
  • 경북 감포지역에서 산출되는 천연 벤토나이트를 이용하여 제올라이트 A를 합성하기 위해 반응기질의 몰비, 반응온도, 반응시간 등에 따른 최적의 합성조건을 조사하였다. 실리카원은 40%-황산용액으로 처리한 천연 벤토나이트를 사용하였고, 알루미늄원은 NaA1O₂를 합성하여 사용하였다. 반응기질의 몰비는 SiO₂ : A1₂O₃ : NaO₂ : H₂O=2 : 1 : 1 : 25와 2 : 1 : 1 : 30이었고, 60℃에서 1시간 묵힘과정을 거친 후 90, 100, 120℃에서 1, 3, 5hr반응시켰다 제올라이트 A의 최적의 합성조건은 SiO₂: Al₂O₃ : Na₂O = H₂O=2 : 1 : 1 : 30이고, 90℃에서 3hr 반응시키는 경우였고, 이 조건에서 합성된 제올라이트의 열적 성질은 79.2℃에서 층간수가 증발하였고, 503.0℃에서 결정수가 탈리되었다. 수분의 감소량은 제올라이트 중량비의 5.9%이었다.

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九龍浦産 天然제올라이트의 物性 및 觸媒特性 (The Physical and Catalytic Properties of Kuryongpo Natural Zeolite)

  • 정종식;서곤;전학제;김호기
    • 대한화학회지
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    • 제21권3호
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    • pp.204-209
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    • 1977
  • 경북 구룡포산 천연제올라이트에 대한 물리적 성질과 촉매활성이 검토되었다. 정량분석과 X-선 회절스펙트럼으로부터 천연제올라이트는 30 ${\sim}$ $40{\%}$의 mordenite를 함유하고 있다. 원시료의 표면적은 $75m^2$/g에 불과하나 2N 염산으로 처리시 $320m^2$/g에 이른다. 톨루엔불균화 반응에 대해서도 2N에서 최대의 전화율을 보여주나, 활성저하가 심한 것으로 나타났으며 크실렌에 대한 벤젠의 선택성은 처리한 산농도가 증가함에 따라 감소하는 것으로 나타났다.

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Polymorphisms and expression levels of TNP2, SYCP3, and AZFa genes in patients with azoospermia

  • Mohammad Ismael Ibrahim Jebur;Narges Dastmalchi;Parisa Banamolaei;Reza Safaralizadeh
    • Clinical and Experimental Reproductive Medicine
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    • 제50권4호
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    • pp.253-261
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    • 2023
  • Objective: Azoospermia (the total absence of sperm in the ejaculate) affects approximately 10% of infertile males. Despite diagnostic advances, azoospermia remains the most challenging issue associated with infertility treatment. Our study evaluated transition nuclear protein 2 (TNP2) and synaptonemal complex protein 3 (SYCP3) polymorphisms, azoospermia factor a (AZFa) microdeletion, and gene expression levels in 100 patients with azoospermia. Methods: We investigated a TNP2 single-nucleotide polymorphism through polymerase chain reaction (PCR) restriction fragment length polymorphism analysis using a particular endonuclease. An allele-specific PCR assay for SYCP3 was performed utilizing two forward primers and a common reverse primer in two PCR reactions. Based on the European Academy of Andrology guidelines, AZFa microdeletions were evaluated by multiplex PCR. TNP2, SYCP3, and the AZFa region main gene (DEAD-box helicase 3 and Y-linked [DDX3Y]) expression levels were assessed via quantitative PCR, and receiver operating characteristic curve analysis was used to determine the diagnostic capability of these genes. Results: The TNP2 genotyping and allelic frequency in infertile males did not differ significantly from fertile volunteers. In participants with azoospermia, the allelic frequency of the SYCP3 mutant allele (C allele) was significantly altered. Deletion of sY84 and sY86 was discovered in patients with azoospermia and oligozoospermia. Moreover, SYCP3 and DDX3Y showed decreased expression levels in the azoospermia group, and they exhibited potential as biomarkers for diagnosing azoospermia (area under the curve, 0.722 and 0.720, respectively). Conclusion: These results suggest that reduced SYCP3 and DDX3Y mRNA expression profiles in testicular tissue are associated with a higher likelihood of retrieving spermatozoa in individuals with azoospermia. The homozygous genotype TT of the SYCP3 polymorphism was significantly associated with azoospermia.

Immunomodulating activities of water extract from xanthium strumarium 2

  • Moon, Eun-Yi;Park, Seung-Yong;Ahn, Mee-Ja;Ahn, Jong-Woong;Zee, Ok-Pyo;Park, Eun-kyue
    • Archives of Pharmacal Research
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    • 제14권3호
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    • pp.217-224
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    • 1991
  • One of water and/or methanol extracts from 14 herbal deugs which were screened using murine splenocytes showed immunosuppressive activities previously. After water extract from Xanthium strumarium was treated with chloroform. $100 \mu{g/ml}$ of water layer (XS-WCI) has very strong immunosimulating activities tested by $^3H$-thmidine incorporation (control as $100 \mu{g/ml}$, 26345 cpm was 69515 cpm). MLR also appears to be simulated strongly (control vs $100 \mu{g/ml}$, 4962 cpm vs 78688 cpm). When $100 \mu{g/ml}$ of XS-WCI and $0.8 \mu{g/ml}$ of concanavalin a (ConA) were added. more $^3H$-thymidine were incorporated significantly, compared with $0.8 \mu{g/ml}$ of ConA only. In contrast with ConA. results from $5 \mu{/ml}$ of lipopolysaccharide (LPS) and $100 \mu{g/ml}$ of XS-WCI were not different. compared with $5\mu{/ml}$of LPS only. These results indicated the responses of XS-WCI to B cell and T cell may be different. XS-WCI was injected intraperitoneally (10 mg/kg. 50mg/kg/ 100 mg/kg) for 4 days or 10 days and tested secretion of IgM or IgG by direct and indirect hemolytic plaque-forming cell assays, respectively. Numbers of hemolytic plaques for both IgM and IgG were increased significantly. Especially, secretion of IgGs was increased more than 10 times. After administration of XS-WCI for 7 days (50 mg/kg. 100 mg/kg) splenomegaly deu to graft vs host reaction was observed. Human lymhocytes separated from whole blood by Ficoll-Hypaque method were also proliferated after treatment of $10 \mu{g/ml}$ and $50 \mu{g/ml}$ of XS-WCI. As seen in murine lymphocytes, human lymphocyte proliferation was increased synergistically after treatment with both of XS-WCI and phytohemagglutinin (PHA). It appears that XS-WCI may have potential immunosimulating activities and that it remains to be purified further for isolation of active components.

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폐 농업용 비닐 수지에서 연료유 생성을 위한 원료 수지의 열분해 반응에서 제올라이트계 촉매의 영향 (The Effects of Zeolite-Type Catalysts on the Pyrolysis Reaction of Raw Material Resin to Produce Fuel-Oil from Waste Vinyl)

  • 박영철;최주홍;조태호
    • Korean Chemical Engineering Research
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    • 제47권3호
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    • pp.303-309
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    • 2009
  • 폐 농업용 비닐을 이용한 연료유 생산 공정을 위한 저밀도폴리에틸렌(LDPE)과 에틸렌비닐아세테이트(EVA) 수지에 대한 열분해 반응 실험을 하였다. 질소 분위기에서 상온에서 $650^{\circ}C$까지의 비등온 조건에서의 열분석기(열중량분석기, 시차주사열량계)와 $420^{\circ}C$의 배치형 반응기에서 무촉매 반응과 천연제올라이트, FCC 촉매, 폐 FCC 촉매, 중국 촉매(촉매 A) 등의 제올라이트계 촉매를 사용한 열분해가 행하여졌다. TGA 실험에서 무적제가 첨가된 EVA 수지는 열분해 개시 온도가 $250^{\circ}C$ 근처로 매우 낮아졌으나, 황토와 장수제 첨가는 열분해를 다소 지연시켰다. LDPE에서 제올라이트 계열 촉매는 촉매 A>폐 FCC 촉매>천연제올라이트>LDPE의 순으로 열분해 반응속도를 높이는데 유효하였다. EVA에서 제올라이트 계열 촉매 첨가 시는 폐 FCC 촉매>천연제올라이트>촉매 A>EVA 수지의 순으로 열분해 반응을 촉진시켰다. DSC 실험에서 제올라이트 계열 촉매 첨가 시 촉매 A>폐 FCC 촉매>천연제올라이트>LDPE의 순으로 융해개시 온도와 열분해열이 낮아졌다. 회분식 실험에서 천연제올라이트 첨가 시 시료 중 가장 높은 액상의 연료유 생성수율을 얻었다.

New Photopolymers Composed of Photoreactive Binder for Holographic Applications (I)

  • Choi, Dong-Hoon;Yoon, Han-Na;Yoon, Hyuk;Lee, Geon-Joon;Feng, De-jun;Kim, Jae-Hong;Paik, Sang-Hyun;Choi, Suk-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.230-233
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    • 2003
  • New photopolymers were designed and prepared using the photosensitive polymer binders. The photochemical reaction of the photosensitive polymer binder was studied by virtue of UV absorption and infrared spectroscopy. The holographic gratings were successfully fabricated in these photopolymer film samples by conventional optical interference method. We also investigated the effect of photocrosslink in the polymer binder on the diffraction behavior of the photopolymer. The dynamic behaviors of the grating formation were studied with the change of exposure intensity in terms of the diffraction efficiency. Particularly, we focused our efforts to observe the variation of the diffraction efficiency during post UV curing process.

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천연재료와 합성색소 첨가에 따른 마카롱의 품질 특성 (Characteristics of Macaroons prepared with Natural Materials and Artificial Food Colorant)

  • 박옥자;박미혜;이승환;이선미
    • 한국식품영양학회지
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    • 제31권5호
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    • pp.631-639
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    • 2018
  • The purpose of this study was to investigate the characteristics of macaroons prepared using natural color materials (Opuntia ficus-indica var. saboten (Re-N), mulberry leaf (Gr-N), pumpkin (Ye-N), and cocoa powder (Br-N)) and corresponding artificial food colorants (red (Re-A), yellow (Ye-A), green (Gr-A) and brown (Br-A)). The moisture content of macaroons prepared using natural color material was higher compared to the macaroons prepared using artificial food colorant. DPPH and ABTS radical scavenging activity was similar in both types of macaroons. Lightness and redness of Re-N, Gr-N, Ye-N, and Br-N macaroons were lower than Re-A, Gr-A, Ye-A and Br-A macaroons. Yellowness of Re-N was higher because of the browning reaction. The texture profile analysis revealed lower hardness when natural color powder was employed. In the sensory evaluation, overall acceptability was not significantly different between natural colored and artificial colored macaroons. As a result, macaroons with the natural color material were softer and showed higher antioxidative activity, however, organoleptic properties were not much different when compared with macaroons with artificial colors. Apparently, it is stated that more studies on the development of macaroons with more enhanced physical functionality and good taste using natural materials should be performed.

A Study on the Dyeing Characteristics by Reproduction of Hwangsu Spring

  • Ahn, In-Yong;Suh, Hwa-Jin;Song, Eun-Young;Na, Seon-Young;Park, Ji-Ju;Park, Young-Mi;Jung, Jin-Young;Kwon, Oh-Oun
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2011년도 제45차 학술발표회
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    • pp.42-42
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    • 2011
  • To evaluate the Hwangsu spring as natural mordants effect on dyeing. The natural mordants effect of Hwangsu spring were analyzed by pH, temperature, trace elements, organic matter and color fastness. Hwangsu spring having pH 2.42 and $14.4^{\circ}C$ was harvested at the end of September, in Yeongcheon (Gyeongbuk Province, Korea) and left on a $0^{\circ}C$ and $25^{\circ}C$ before use. Hwangsu spring during storage at $25^{\circ}C$ turned brown by photochemical reaction. The Result of ICP analysis, it contained Fe(414.9 ppm), Al(88.9 ppm), Mn(4.9 ppm) and observed character by water analysis. Dyeing and post-mordant procedure; Cotton(KS K 0905) were dyed with clove powder for 30 min at $70^{\circ}C$. Hwangsu spring, Aluminium Sulfate $14-18H_20(Al_2(SO_4)_3{\cdot}14-18H_2O)$, Iron Sulfate Heptahydrate($FeSO_4{\cdot}7H_2O$) were used by post mordant at the same ratio. The dyed fabrics were treated with 20% each mordant solution at $25^{\circ}C$ for 10min. Comparison with a reproduced chemical mordant, the K/S values of cotton fabrics dyed with Hwangsu sping were increased.

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양식수산물 자연재해 피해조사의 문제점과 개선방향 연구 (Problems and Improvement Directions for Damage Investigation of Aquaculture Products from Natural Disaster)

  • 강종호;문건호
    • 수산경영론집
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    • 제50권3호
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    • pp.31-42
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    • 2019
  • This study aims to determine problems of the damage investigation system of aquaculture products resulting from natural disaster and to deduce improvement plans for such problems. The main problems revealed from this study were as follows: 1) detailed damage investigation is carried out only by one particular organization, 2) for aquaculture insurance subscribers another detailed damage investigation is conducted to reveal the causes of natural disaster by a joint investigator team formed according to a different legislation with a different purpose, 3) damage investigation is usually suffered from lack of labor, budget and time due to the restriction of natural damage to a certain period of season leading to the absence of quick reaction capability for irresistible natural disasters, and 4) there are no specified procedures and protocols for deciphering causes of a natural demage. The improvement plans to find solutions for such problems are as follows: 1) for the investigation, the object, method and role of the investigation organization should be clarified by improving the present legislation, 2) investigation methods for determining the demage causes should be systematized by making a manual to minimize disputes, and 3) supports for the investigation organization should be institutionalized to guarantee sufficient budget and manpower. Under the present circumstance with continuous natural damages, smooth procedures of damage compensation would lead to the management stability of aquaculture farms.