• Title/Summary/Keyword: phase-contrast

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A Study on the Effects of Visual Aesthetics and Usability of Web Site Design on their Performance (웹사이트 디자인의 시각적 요소와 유용성이 성과에 미치는 영향에 관한 연구)

  • Kim, Seung-Kyung;Lee, Jae-Kwan
    • Journal of the Korean Operations Research and Management Science Society
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    • v.32 no.2
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    • pp.17-40
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    • 2007
  • Most research on web site design has focused on technological factors, while visual aesthetic factors have been considered less important. In contrast, this study focuses on visual aesthetic factors in web site design. Findings of this study can be summarized as follows : (1) The result of SPSS-factor analysis shows that there are 3 distinct factors, 'classical aesthetics', 'expressive aesthetics', and 'usability' 'Classical aesthetics' and 'expressive aesthetics' can be described by visual aesthetic design, 'Visual aesthetic design' can be distinguished from 'usability'. This conceptual confusion relating to 'usability' and 'visual aesthetic design' can be clarified by these findings. (2) As a result of multiple regression analyses, 'classical aesthetics', 'expressive aesthetics', and 'usability' have a positive influence on 'interactivity' and 'web site evaluation'. This research clarifies the concepts of 'expectations' of Grier [18] and 'engagement' of Rosen and Purinton [33] as the 'interactivity' between users and web sites. Furthermore, this research suggests a valid model with high $R^2$(interactivity, 48% : web site evaluation, 68%). (3) Empirical tests show that the differences among users in 'entry point' are related to the characteristics of web sites and the personal characteristics of users. The differences among users in terms of 'scanning time' are closely related to the attitudes and evaluation tendencies of users with respect to web sites. These findings could contribute to the 'search phase' of the Faraday model [16], enabling it to be more precise and extensible. The managerial implication of this study is that customers' preferences regarding web site designs are differences, as their preferences are based on their individual characteristics. Therefore, marketing managers should consider promotional tools on web sites that are relevant to the target market. An optimal strategy for web design could be a carefully-selected combination of factors that are relevant to the 'interactivity' and 'evaluation' of web sites. Additionally, if marketing managers want to attract more favorable attitudes and more affirmative evaluations from users, web sites should be designed so that they are understood more quickly by users. finally, this study suggests that 'good design' for web sites depends on understanding how to attain the appropriate balance between 'classical aesthetics' and 'expressive aesthetics', based on the target customer.

ADAMTS13 Activity in Childhood Hemolytic Uremic Syndrome(HUS) (소아 용혈성요독증후군에서 ADAMTS13 활성도의 변화)

  • Lee, Cho-Ae;Kim, Nam-Keun;Jang, Moon-Ju;Lee, Jun-Ho;Cheong, Hae-Il;Lee, Sun-Ju;Park, Hye-Won;Oh, Do-Yeon
    • Childhood Kidney Diseases
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    • v.10 no.2
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    • pp.109-118
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    • 2006
  • Purpose : HUS usually occurs in children after infection with shiga toxin-producing microorganism(D+HUS). In contrast, non-postdiarrheal(D-) HUS occurs at any age and has a high rate of relapse and a poor prognosis. The clinical presentation of D-HUS is similar to that of thrombotic thrombocytopenic purpura(TTP). Recently severe deficiencies of ADAMTS13 were reported not only in TTP and D- HUS but also in D+ HUS during their acute phase. The purpose of the study is to evaluate the plasma ADAMTS13 activity in D+ and D-HUS. Methods : Nineteen children with HUS(D+ HUS 12 and D- HUS 7) were enrolled. The assays of plasma ADAMTS13 activity were performed during the acute stage in the D+ HUS and at various stages of relapsing courses in the D- HUS patients by multimer assay, based on electrophoresis. Results : The median plasma activity of ADAMTS13 in D+ HUS and D- HUS were 80.9%(37.8-132.4%) and 53.9%(1.0-94.1%), respectively, which were not statistically significantly different from control(86.4%, 34.2-112.3%)(P>0.05). One boy with D- HUS had severe deficiency of ADAMTS13(1.0%). His platelet count was normalized temporarily by fresh frozen plasma infusion. Conclusion : We have demonstrated that there is no significant difference of the plasma ADAMTS13 activity between D+ HUS, D- HUS and control. We detected severe deficiency of ADAMTS13 in one boy who presented with relapsing episodes of D- HUS. ADAMTS13 deficiency should be considered in the subgroup of D- HUS especially with early onset and recurrent courses. Plasma therapy can be beneficial in this subgroup.

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The Effects of Polygala Tenuifolia DM Fraction on CT105-injuried Neuronal Cells (원지 디클로로메탄분획이 CT105에 의한 신경세포 상해에 미치는 영향)

  • Lee Sang Won;Kim Sang Ho;Kim Tae Heon;Kang Hyung Won;Lyu Yeoung Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.2
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    • pp.507-516
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    • 2004
  • Alzheimer's disease(AD) is a geriatric dementia that is widespread in old age. In the near future AD will be the commom disease in public health service. Although a variety of oriental presciptions in study POD(Polygala tenuifolia extracted from dichlorometan) have been traditionally utilized for the treatment of AD, their pharmacological effects and action mechanisms have not yet fully elucidated. It has been widely believed that AP peptide divided from APP causes apoptotic neurotoxicity in AD brain. However, recent evidence suggests that CT105, carboxy terminal 105 aminoacids peptide fragment of APP, may be an important factor causing neurotoxicity in AD. SK-N-SH cells expressed with CT105 exhibited remarkable apoptotic cell damage. Based on morphological observations by phase contrast microscope and NO formation in the culture media, the CT105-induced cell death was significantly inhibited by POD. In addition, AD is one of brain degeneration disease. So We studied on herbal medicine that have a relation of brain degeneration. From old times, In Oriental Medicine, PO water extract has been used for disease in relation to brain degeneration. We were examined by ROS formation, neurite outgrowth assay and DPPH scravage assay. Additionally, we investigated the association between the CT105 and neurite degeneration caused by CT105-induced apoptotic response in neurone cells. We studied on the regeneratory and inhibitory effects of anti-Alzheimer disease in pCT105-induced neuroblastoma cell lines by POD. Findings from our experiments have shown that POD inhibits the synthesis or activities of CT105, which has neurotoxityies and apoptotic activities in cell line. In addition, treatment of POD(>50 ㎍/㎖ for 12 hours) partially prevented CT(105)-induced cytotoxicity in SK-N-SH cell lines, and were inhibited by the treatment with its. POD(>50 ㎍/㎖ for 12 hours) repaired CT105-induced neurite outgrowth when SK-N-SH cell lines was transfected with CT105. As the result of this study, In POD group, the apoptosis in the nervous system is inhibited, the repair against the degerneration of Neuroblastoma cells by CT105 expression is promoted. Decrease of memory induced by injection of scopolamin into rat was also attenuted by POD, based on passive avoidance test. Taken together, POD exhibited inhibition of CT105-induced apoptotic cell death. POD was found to reduce the activity of AchE and induced about the CA1 in rat hippocampus. Base on these findings, POD may be beneficial for the treatment of AD.

The Effects of Various Extracellular Matrices on Motility of Cultured MC3T3-E1 Cell (다양한 세포외기질이 배양 골아세포의 이동에 미치는 영향)

  • Park, Beyoung Yun;Seo, Sang Woo;Lee, Won Jai;Ryu, Chang Woo;Rah, Dong Kyun;Son, Hyun Joo;Park, Jong Chul
    • Archives of Plastic Surgery
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    • v.32 no.2
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    • pp.143-148
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    • 2005
  • Chemotactic migration of bone forming cell, osteoblast, is an important event during bone formation, bone remodeling, and fracture healing. Migration of cells is mediated by adhesion receptors, such as integrins, that link the cell to extracellular matrix ligands, type I collagen, fibronectin, laminin and depend on interaction between integrin and extracellular ligand. Our study was designed to investigate the effect of extracellular matrix like fibronectin, laminin, type I collagen on migration of osteoblast. Migration distance and speed of MC3T3-E1 cell on extracellular matrix-coated glass were measured for 24 hours using 0.01% type I collagen, 0.01% fibronectin, 100 microliter/ml laminin. The migration distance and speed of MC3T3-E1 cell was compared using a video-microscopy system. To determine migration speed, cells were viewed with a 4 phase- contrast lens and video recorded. Images were captured using a color CCD camera and saved in 8-bit full-color mode. The migration distance on 0.01% type I collagen or 0.01% fibronectin was longer than that on $100{\mu}l/ml$ laminin-coated glass. The migration speed on fibronectin-coated glass was 68 micrometer/hour which was fastest. The migration speed on type I collagen-coated glass was similar with that on fibronectin-coated glass. The latter two migration speeds were faster than that on no-coated glass. On the other hand, the average migration speed on laminin-coated glass was 37micrometer/hour and not different from that of control group. In conclusion, the extracelluar matrix ligands such as type I collagen and fibronectin seem to play an important role in cell migration. The type I collagen or fibronectin coated scaffold is more effective for migration of osteoblast in tissue engineering process.

Metallurgical Investigation and Functional Consideration of the Iron Swords from Bongseon-ri Site in Seocheon (서천 봉선리유적 출토 철제대도의 금속학적 조사 및 기능성 고찰)

  • Cho, Hyun Kyung;Jung, Young Sang;Cho, Nam Chul;Lee, Hun
    • Journal of Conservation Science
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    • v.30 no.2
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    • pp.111-122
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    • 2014
  • In Bongseon-ri site, the central type and the local type of the Baekje tombs co-exist together. Many swords with ring pommel which to regional leaders in Seocheon the Beekje government granted are excavated from these tombs. These represent that the regional leaders were controlled by the Baekje government gradually. Four swords with ring pommel and one simple sword are investigated metallurgically and we seek what swords have a function of weapon or what sword produce for grave goods. The simple sword is made by solid carburizing technology and quenching of heat treatment so it's possibly used as a weapon. In contrast, four swords with ring pommel has little chance of weapon because the blade of swords consists of microstructure that have low hardness and the back of swords don't have microstructure can absorb the shock. The most identical characteristic of the simple sword and swords with ring pommel is that they are possible to classify clearly into practical/non-practical tools. Additionally, according to non-metallic inclusion analysis result of these swords, w$\ddot{u}$stite and glass phase are found together. Thus, it is able to say that reduction method in low temperature is applied during smelting process.

In Vivo Measurement of Extracellular Monoamines and Their Metabolites in the Rat Posterior Hypothalamus Using Microdialysis Technique (미세투석법을 이용하여 흰쥐 후 사상하부에서 세포외액의 모노아민과 대사체들의 생체내 측정)

  • Sung, Ki-Wug;Kim, Seong-Yun;Cho, Young-Jin;Lee, Kweon-Haeng;Lee, Sang-Bok
    • The Korean Journal of Pharmacology
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    • v.28 no.1
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    • pp.1-9
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    • 1992
  • Catecholamines, serotonin and their metabolites were measured in the posterior hypothalamus of urethane-anesthetized normotensive Wistar Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) using brain microdialysis which is a recently developed experimental method to measure the release of neurotransmitters and their metabolites at the localized brain area in vivo. Microdialysis probe was implanted stereotaxically to the rat posterior hypothalamus and perfused by Ringer's solution. Monoamines and their metabolites were quantified by reverse phase high performance liquid chromatography with electrochemical detection. In vitro recovery test of microdialysis showed that there exist inverse relationship between the perfusion flow rate and the relative recovery of neurochemical compounds. The estimated extracellular concentration of dopamine was about 32 nM, of norepinephrine 50 nM, of epinephrine 50 nM, of serotonin 73 nM, of 3, 4-dihydroxyphenylacetic acid (DOPAC) 281 nM, of homovanillic acid (HVA) 181 nM, and of 5-hydroxyindoleacetic acid (5HIAA) 3767 nM in the hypothalamic perfusate of the normotensive rat. There was no difference in the basal level of monoamines between the SHR and the WKY. In contrast, the level of DOPAC, HVA and 5HIAA in SHR was higher than that in the WKY, This study demonstrated that the microdialysis technique should be an applicable tool for in vivo measurement of central neurochemical substances.

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Characterization of gp64 Gene of Bombyx mori Nucleopolyhedrovirus and Development of a Transient Expression Vector (누에 핵다각체병 바이러스 헤 gp64 유전자의 특성조사 및 transient 발현 벡터 개발)

  • 김미향;최재영;우수동;이해광;제연호
    • Microbiology and Biotechnology Letters
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    • v.29 no.1
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    • pp.18-24
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    • 2001
  • Expression of the baculovirus major envelope glycoprotein gene(gp64) is regulated by transcription from botha early and late promoters. To develop a transient expression vector under the control of gp64 gene promoter, the gp64 gene of Bombyx mori nucleopolyhedrovirus-K1(BmNPV-K1) was characterized. The gp64 gene was local-ized at EcoR I-Pst I 7.38-kb fragment of the BmNPV-K1 genome. The EcorR 1-Pst I 7.38-kb fragment was cloned and the nucleotide sequence of 2,277 bases including the coding region of gp64 gene was determined. Based on these results, transient expression vector using gp64 gene promoter was constructed and named as pBm64. E.coli lacZ gene was introduced onto pBm64 as a reporter gene and expressed transiently in B. mori 5(Bm 5) cells. The expression vector transfected into the cells was maintained stably for 1 to 5 days. In order to confirm the expression of the reporter gene by gp64 promoter, recombinant virus was constructed. The recombinant virus has two independent transcription units in opposite orientations with two promoters; gp64 and polyhedrin gene promoters each initiating transcription of $\beta$-galactosidase and polyhedrin, respectively. Polyhedra formation and expression of $\beta$-galactosidase in Bm5 cells infected with the recombinant virus were observed with phase contrast microscope and in situ staining.

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Effects of Dissolved Oxygen Level on Avermectin $B_{1a}$ Production by Streptomyces avermitilis in Computer-Controlled Bioreactor Cultures

  • Song, Sung-Ki;Jeong, Yong-Seob;Kim, Pyeung-Hyeun;Chun, Gie-Taek
    • Journal of Microbiology and Biotechnology
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    • v.16 no.11
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    • pp.1690-1698
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    • 2006
  • In order to investigate the effect of dissolved oxygen (DO) level on AVM $B_{1a}$ production by a high yielding mutant of Streptomyces avermitilis, five sets of bioreactor cultures were performed under variously controlled DO levels. Using an online computer control system, the agitation speed and aeration rate were automatically controlled in an adaptive manner, responding timely to the oxygen requirement of the producer microorganism. In the two cultures of DO limitation, the onset of AVM $B_{1a}$ biosynthesis was observed to casually coincide with the fermentation time when oxygen-limited conditions were overcome by the producing microorganism. In contrast, this phenomenon did not occur in the parallel fermentations with DO levels controlled at around 30% and 40% throughout the entire fermentation period, showing an almost growth-associated mode of AVM $B_{1a}$ production: AVM $B_{1a}$ biosynthesis under the environments of high DO levels started much earlier than the corresponding oxygen-limited cultures, leading to a significant enhancement of AVM $B_{1a}$ production during the exponential stage. Consequently, approximately 6-fold and 9-fold increases in the final AVM $B_{1a}$ production were obtained in 30% and 40% DO-controlled fermentations, respectively, especially when compared with the culture of severe DO limitation (the culture with 0% DO level during the exponential phase). The production yield ($Y_{p/x}$), volumetric production rate (Qp), and specific production rate (${\bar{q}}_p$) of the 40% DO-controlled culture were observed to be 14%, 15%, and 15% higher, respectively, than those of the parallel cultures that were performed under an excessive agitation speed (350 rpm) and aeration rate (1 vvm) to maintain sufficiently high DO levels throughout the entire fermentation period. These results suggest that high shear damage of the high-yielding strain due to an excessive agitation speed is the primary reason for the reduction of the AVM $B_{1a}$ biosynthetic capability of the producer. As for the cell growth, exponential growth patterns during the initial 3 days were observed in the fermentations of sufficient DO levels, whereas almost linear patterns of cell growth were observed in the other two cultures of DO limitation during the identical period, resulting in apparently lower amounts of DCW. These results led us to conclude that maintenance of optimum DO levels, but not too high to cause potential shear damage on the producer, was crucial not only for the cell growth, but also for the enhanced production of AVM $B_{1a}$ by the filamentous mycelial cells of Streptomyces avermitilis.

Enhancement of cyanoacrylate-developed marks using p-dimethylaminobenzaldehyde (DMAB) on semi-porous surfaces and analysis of the influence factors on fluorescence intensity (반다공성 재질에 유류된 지문의 CA 훈증 후 p-dimethylaminobenzealdehyde(DMAB) 형광시약 적용 시 표면적과 주변 온도, 기압이 형광착색에 미치는 효과에 관한 연구)

  • Yu, Je-Sul;Kim, Ju-Hah
    • Analytical Science and Technology
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    • v.27 no.4
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    • pp.187-195
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    • 2014
  • It is very important to minimize the damage of latent fingerprints at enhancing the contrast. This study proves the enhancement effects of cyanoacrylate-fumed latent fingerprints using p-dimethylaminobenzealdehyde (DMAB) on semi-porous surfaces and the influence factors. The latent fingerprints in experiment were developed for cyanoacrylate treatment in a vacuum chamber and used after drying at room temperature for 24 hours. For fluorescence staining, the cyanoacrylate-developed marks using DMAB were sublimated during 48 hours under the different conditions of surface area, temperature, atmospheric pressure. First experiment showed how surface area effects on the sublimation rate and fluorescence intensity by DMAB of particle size and container size. In addition, the fluorescence staining using DMAB with solvent-free contact method had the greatest fluorescence intensity after 36 hours and a low fluorescence intensity over a certain size of surface area. Second experiment showed that the evaporation of DMAB solid crystals got a satisfying result in a temperature of $20^{\circ}C$ and reduced time to get the greatest fluorescence intensity. It took a long time to get a optimum level of fluorescence intensity at $30^{\circ}C$ or more and it was less effective in fluorescence intensity. Third experiment on the pressure indicated that the fluorescence intensity of vacuum was weaker than nonvacuum but it was inapplicable to very high variations in pressure.

Cytotoxicity Assessments of Portulaca oleracea and Petroselinum sativum Seed Extracts on Human Hepatocellular Carcinoma Cells (HepG2)

  • Farshori, Nida Nayyar;Al-Sheddi, Ebtesam Saad;Al-Oqail, Mai Mohammad;Musarrat, Javed;Al-Khedhairy, Abdulaziz Ali;Siddiqui, Maqsood Ahmed
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.16
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    • pp.6633-6638
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    • 2014
  • The Pharmacological potential, such as antioxidant, anti-inflammatory, and antibacterial activities of Portulaca oleracea (PO) and Petroselinum sativum (PS) extracts are well known. However, the preventive properties against hepatocellular carcinoma cells have not been explored so far. Therefore, the present investigation was designed to study the anticancer activity of seed extracts of PO and PS on the human hepatocellular carcinoma cells (HepG2). The HepG2 cells were exposed with $5-500{\mu}g/ml$ of PO and PS for 24 h. After the exposure, cell viability by 3-(4,5-dimethylthiazol-2yl)-2,5-biphenyl tetrazolium bromide (MTT) assay, neutral red uptake (NRU) assay, and cellular morphology by phase contrast inverted microscope were studied. The results showed that PO and PS extracts significantly reduced the cell viability of HepG2 in a concentration dependent manner. The cell viability was recorded to be 67%, 31%, 21%, and 17% at 50, 100, 250, and $500{\mu}g/ml$ of PO, respectively by MTT assay and 91%, 62%, 27%, and 18% at 50, 100, 250, and $500{\mu}g/ml$ of PO, respectively by NRU assay. PS exposed HepG2 cells with $100{\mu}g/ml$ and higher concentrations were also found to be cytotoxic. The decrease in the cell viability at 100, 250, and $500{\mu}g/ml$ of PS was recorded as 70%, 33%, and 15% by MTT assay and 63%, 29%, and 17%, respectively by NRU assay. Results also showed that PO and PS exposed cells reduced the normal morphology and adhesion capacity of HepG2 cells. HepG2 cells exposed with $50{\mu}g/ml$ and higher concentrations of PO and PS lost their typical morphology, become smaller in size, and appeared in rounded bodies. Our results demonstrated preliminary screening of anticancer activity of Portulaca oleracea and Petroselinum sativum extracts against HepG2 cells, which can be further used for the development of a potential therapeutic anticancer agent.