• Title/Summary/Keyword: retardation also

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Characteristic as a Gene Delivery System of Water Soluble Chitosan Conjugated with Cationic Peptide (양이온 펩타이드가 컨쥬게이트된 수용성 키토산의 유전자 전달체로서의 특성)

  • Kim, Young-Min;Kim, Ji-Ho;Park, Seong-Cheol;Park, Yung-Hoon;Jang, Mi-Kyeong
    • KSBB Journal
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    • v.31 no.4
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    • pp.300-311
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    • 2016
  • Recently gene delivery has been designed newly using bioactive biomaterial and applied in the various field by many researchers. In this study, we proposed a new gene delivery system which has the capability of targeting effect in the specific tissue and remarkably enhanced transfection efficiency. We investigated $^1H-NMR$ spectroscopy, particle size analyzer and gel retardation to confirm the correct preparation of gene delivery. Also, we identified the hemo-compatibility of gene delivery by hemolysis assay, non-cytotoxicity by MTT test and transfection efficiency. The uptake mechanism of the gene carrier was confirmed using inhibitor agent such as sodium azide, indomethacin, quercetin, colchicine, and chloropromazine. As a results, it was identified that gene carrier prepared by in this study entered in the cell by the microtubule-dependent, energy-dependent and clathrin-mediated endocytosis pathway.

A Study on the Retarding effects of Cememtn Mortar Setting (시멘트 모르타르의 응결 지연 효과에 관한 연구)

  • 이재한;이경희;김홍기
    • Journal of the Korean Ceramic Society
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    • v.33 no.3
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    • pp.307-312
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    • 1996
  • In following addition of 0.3, -0.6, 0.8, 1.0 and 5 weight percent MgSiF66H2O studies have been made of the setting and hardening characteristics of ordinary portland cement. MgSiF66H2O retarded the setting time of ordinary portland cement and extended the induction pariod of the hydration. In ordinary portland cement the setting characteristics were drastically altered especially at high MgSiF66H2O contents. Evidence was also obtained by the formation of a KSiF6 which was very fine particle. The results wee as follows. 1. Slump was slightly decreased when MgSiF66H2O added. 2. Setting time was retarded depending on the amount of retarding agent 2 to 8 hours 3. Compressive strength was almost same or some increased in comparision with opc. 4. When MgSiF66H2O was added to cement paste K2SiF6 were formed It was fine-sized distributed uniformly in cement grain and caused retardation of cement setting.

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A Experimental Study on the Fatigue Crack Growth Behavior of Thick Plate with Repaired Crack (보수된 균열을 가진 두꺼운 평판의 피로균열 성장 거동에 관한 실험적 연구)

  • Chung, Ki-Hyun;Yang, Won-Ho;Kim, Cheol;Sung, Ki-Deug
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.292-298
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    • 2001
  • An experimental investigation of the effect of composite patching repair was conducted to characterize the fatigue crack growth behavior in thick A16061-T6 (6mm) panels with single bonded patch by fiber reinforced composite patch. Four patch lengths and no patch plate were examined. An analytical procedure, involving three-dimensional finite element method having three layers to model cracked aluminum plate, epoxy by adhesive and composite patch, is calculated the stress intensity factors. From the calculated stress intensity factors, the fatigue crack growth rates are obtained. At the single patching type, different fatigue crack growth ratios through the plate thickness were investigated by using the experimental and analytical results. The results demonstrated that there was a definite variation in fatigue life depending on the size of composite patch. While crack reached the patch end, retardation of crack growth was also revealed in the bonded repair.

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Speech pathologic evaluation of children with ankyloglossia (설유착증 환자의 언어병리학적 평가)

  • Lee, Ju-Kyung
    • Proceedings of the KSPS conference
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    • 2007.05a
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    • pp.155-157
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    • 2007
  • Objective : There are close relationship between intraoral abnormal structure and speech-functional problem. Patients with cleft palate & ankyloglossia are typical examples. Patients with abnormal structure can be repaired toward normal structure by operation. Ankyloglossia may cause functional limitation - for example, speech disorder - even if adequate surgical treatment were done. And, each individuals have each speech disorders. The objective of this study is to evaluate the speechs of childrens with ankyloglossia, and to determine whether ankyloglossia is associated with articulation problem. We wanted to present criteria for indication of frenectomy. Study design The experimental group is composed of 10 childrens who visited our department of oral and maxillofacial surgery, dental hospital, Chonbuk university, due to ankyloglossia and articulation problem,. The average age is 5 Y 7M, M : F ratio is 4 : 1 at the time of speech test. The VPI consonant discrimination degree, PPVT, PCAT, Nasometer II, Visi-Pitch test result were obtained from each group. Result : There was significant difference for 'language development' through PPVT. Except 3 members of experimental group, all remainder showed retardation for 'language development'. For 'errored consonant rate', data showed more higher scores in alveolar consonant. There 'consonant error' in experimental group, mostly showed 'alveolar consonant', also a major modality of 'consonant error' was mostly distortion. Conclusion : We can judge the severity of ankyloglossia patient by examinig language development degree & speech test of 'alveolar consonant' . And we can make a decision for frenulotomy using these results.

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Combustive Characteristics of Pinus Rigida Treated with Ammonium Salts (암모늄염으로 처리된 리기다 소나무의 연소특성)

  • Chung, Yeong-Jin;Jin, Eui
    • Fire Science and Engineering
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    • v.24 no.5
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    • pp.115-121
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    • 2010
  • This study was performed to test the combustive properties of Pinus rigida-based materials by the treatment of ammonium salts. Pinus rigida plate was soaked in three 20 wt% ammonium salt solutions such as ammonium sulfate (AMSF), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP), respectively, at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). Comparing with virgin pinus rigida plate, specimens treated with the ammonium salts had lower combustive properties and It is supposed that the combustion-retardation properties improved due to the treated ammonium salts in the virgin Pinus rigida. Also, the specimens with treated ammonium salts showed both the lower peak heat release rate (PHRR) and lower total heat release (THR) than those of virgin plate.

Clinical Experiences on the Treatment of Congenital Cutis Aplasia and Craniosynostosis (선천성 두피결손증 및 두개골 조기유합증의 치험 5례)

  • Lee, Kyung-Ho
    • Journal of Yeungnam Medical Science
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    • v.10 no.2
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    • pp.493-505
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    • 1993
  • The congenital cutis aplasia mainly occurs in head, sometimes involving the skull and dura mater. It's cause and the rate of falling ill are not known yet, it is the disease that rate of death is high by the infection, such as, the injured vascular hemorrhange of meningitis. Craniosynostosis is the disease the appears the skull as well as the facial deformity with growing, has from the developmental difficiency, visual distibance, motor disturbance, convulsion to the neurologic impairment of mental retardation, and accompanies the each characteristic deformity following the suture fused. Satisfactory results was achieved by local flap surgery and conservative treatment on the infant, diagnosed as the congenital cutis aplasia, case 1 Also successful treatment experiences of craniosynostosis(oxycephaly, brachycephaly, trigonocephaly, cloverleaf deformity) through the frontal bone advancement and the barrel stave asteotomy, were reviewed & pursues and investigates the intracranial volume of before and after of surgery, and then reports with the literature investigation.

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Candida albicans Can Utilize Siderophore during Candidastasis Caused by Apotransferrin

  • Lee Jue-Hee;Han Yong-Moon
    • Archives of Pharmacal Research
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    • v.29 no.3
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    • pp.249-255
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    • 2006
  • Ability of iron acquisition of pathogenic microorganisms functions as a virulence factor. Candida albicans, a fungal pathogen that requires iron for growth, is susceptible to growth retardation by high-affinity iron binding proteins such as transferrin. Recently, we reported that C. albicans could utilize the heme as a part of heme-containing proteins dissociated by heme oxygenase, CaHMX1. In search of another pathway that C. albicans can use to bypass the growth regulation produced by iron limitation, this present study examined utilization of non-candidal siderophores such as Desferal and rhodotorulic acid (RA) for acquisition of inorganic iron by the fungus. C. albicans secreting no siderophores was cultured in iron-free (pretreated with apotransferrin for 24 h) (culture medium). Once growth of the yeast reached stasis from iron starvation, a siderophore was added to the culture media. Results showed that cultures containing apotransferrin within a dialysis membrane recovered growth to the level of untreated controls, whereas C. albicans yeast cells in direct contact with soluble iron-free (apo) transferrin recovered growth only partially. When static growth from iron limitation was reached, the addition of siderophore-apotransferrin complex to culture medium also permitted the yeast to recover growth from apotransferrin growth regulation. All the data show that C. albicans can utilize the non-candidal siderophores for iron acquisition under transferrin regulation as can pathogenic bacteria.

Study on In Vitro Development of Mouse Embryos (생쥐 수정란의 핵이식후 체외발달에 관한 연구)

  • 박희성;이효종;최상용;박충생
    • Korean Journal of Animal Reproduction
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    • v.14 no.3
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    • pp.205-211
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    • 1990
  • Single nuclei from two-, four- and eight-cell mouse embryos were transplanted into enucleated two-cell mouse embryos by micromanipulation and sendai virum mediated fusion. no significant difference in successful injectin rate and fusion rate was found between the cell stages of nuclear donor embryos. There nuclear transplant embryos receiving different cell stage nuclei were cultured in vitro for 96 hours. 75.3% of 255 embryos receiving 2-cell nuclei, 68.2% of 236 embryos reciving 4-cell nuceli and 46.9% of 228 embryos receiving 8-cell nuclei were developed to blastocyst, respectively. The number of blastomeres was significantly(P<0.05) reduced in the embryos receiving 8-cell nuclei, compared with the embryos receiving 2-cell, 4-cell nuclei or the intact embryos. Also the size of blastocysts was significantly(P<0.05) smaller in the embryos receiving 8-cell nuclei, compared with the intact or other nuclear transplant embryos. These results suggest that single nuclei introduced into the enucleated two-cell embryos are able to support the in vitro development of the reconstituted embryos to blastocysts. The prominant retardation of blastocoele formation and cell division was shown in nuclear transplant embryos receiving eight-cell nuclei when they were cultured in vitro.

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A Study on the Jetting Phenomena in Injection Molding Process (사출성형 공정에서 젯팅 현상에 관한 고찰)

  • Lyu Min-Young
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2002.02a
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    • pp.125-131
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    • 2002
  • Surface defects in injection molded parts are due to the unsteady flow of polymer melt which are related to the geometries of cavity and gate, the operational conditions of injection and the rheological properties of polymer. In this study we have examined jetting phenomena in injection molding process for three kinds of PCs which have different molecular weight and structure, PBT and PC/ABS alloy with several injection speeds. We have used various cavity shapes that are tensile, flexural and impact test specimens with various gate and cavity thicknesses. Through this study we have observed that the formation of surface defect associated with jetting during filling stage in injection molding is strongly related to die swell. This means that the jetting is strongly affected by the elastic property rather than the viscous property in viscoelastic characteristics of molten polymer. Large die swell would eliminate jetting however, the retardation of die swell would stimulate jetting. In the point of mold design, reducing the thickness ratio of cavity to gate can reduce or eliminate jetting and associated surface defects regardless of magnitude of elastic property. It also enlarges process window that can produce steady flow of polymer melt in injection molding.

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Regulatory Viral and Cellular Elements Required for Potato Virus X Replication

  • Kim, Kook-Hyung
    • The Plant Pathology Journal
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    • v.17 no.3
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    • pp.115-122
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    • 2001
  • Potato virus X (PVX) is a flexuous rod-shaped virus containing a single plus-strand RNA. Viral RNA synthesis is precisely regulated by regulatory viral sequences and by viral and/or host proteins. RNA sequence element as well as stable RNA stem-loop structure in the 5' end of the genome affect accumulation of genomic RNA and subgenomic RNA (sgRNA). The putative sgRNA promoter regions upstream of the PVX triple gene block (TB) and coat protein (CP) gene were critical for both TB and CP sgRNA accumulation. Mutations that disrupted complementarity between a region at the 5' end of the genomic RNA and the sequences located upstream of each sgRNA initiation site is important for PVX RNA accumulation. Compensatory mutations that restore complementarity restored sgRNA accumulation levels. However, the extent of reductions in RNA levels did not directly correlate with the degree of complementarity, suggesting that the sequences of these elements are also important. Gel-retardation assays showed that the 5' end of the positive-strand RNA formed an RNA-protein complex with cellular proteins, suggesting possible involvement of cellular proteins for PVX replication. Future studies on cellular protein binding to the PVX RNA and their role in virus replication will bring a fresh understanding of PVX RNA replication.

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