• Korean Chemical Engineering Research
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• v.43 no.6
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• pp.740-744
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• 2005

Perovskite-type oxide $La_{1-x}Sr_xCo_{1-y}Fe_yO_{3-{\delta}}$ sols were prepared by sol-gel method using $La(NO_3)_3{\cdot}xH_2O$, $Sr(NO_3)_2$, $Co(NO_3)_2{\cdot}6H_2O$ and $Fe(NO_3)_3{\cdot}9H_2O$ as starting materials. The properties of the perovskite-type oxide sols were investigated by viscometer, FT-IR, TG-DTA and XRD. The prepared sols showed 1.16 cp in average viscosity, and a strong acidic condition of pH 0.5, irrespective of composition of the starting materials. The viscosity of sols at the same volume decreases, but the gelation time of sols, at which the sol viscosity increases rapidly, increases when increasing La concentration in composition of starting materials.

• The Journal of Korean Obstetrics and Gynecology
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• v.23 no.3
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• pp.38-55
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• 2010

Purpose: This study was designed to find out the anti-cancer effects of Samultang-Gami which was composed of Rehmanniae Radix(RR), Angelicae Gigantis Radix(AGR), Cnidii Rhizoma(CR), Paeoniae Radix(PR), Cortex Moutan Radicis(CMR), Hedyotis Diffusa(HD) and Caesalpinia Sappan on HeLa, HepG2 and AGS cells. Methods: Various cancer cell lines including HeLa, HepG2 and AGS cells, were used. In vitro anti-cancer effects were measured by MTT assay using cancer cell lines treated with various concentrations of 70% ethanol extract of Samultang-Gami. Expression of cell cycle arrest mediators including Bax, Bcl-2, p53 and DARP-1 proteins were measured by Western blot analysis. Results: 1. Samultang-Gami decreased the viability of HeLa and HepG cells in a dosedependent manner. 2. AGR, CMR, PR and HD decreased the viability of HeLa, HepG2 and AGS cells. 3. We could observe that the decreased Bax and Bcl-2 expression level and the increased PARP-1 expression level by Samultang-Gami extracts treated in HeLa cells. 4. We could observe that the decreased Bcl-2 expression level and the increased Bax, p53 and PARP-1 expression level by RR extracts treated in HeLa cells. and also could observe that the reduction of the protein level of Bcl-2, p53 and PARP-1 and the increase of the protein level of Bax by PR in HeLa cells. 5. We could observe that the increased p53 expression level, the decreased PARP-1's that and the unchanged Bax and Bcl-2's that by Samultang-Gami extracts treated in HepG2 cells. 6. We could observe that the reduced Bcl-2 expression level by each of RR extracts and PR extracts in HepG2 cells. 7. The treatment of Samultang-Gami in AGS cells didn't have any effect on the expression level of Bax, Bcl-2, p53 and PARP-1. 8. We could observe that the increased p53 and PARP-1 expression level by each of CR, RR and PR extracts in AGS cells. Conclusion: Taken together, we suggest that Samultang-Gami exhibits cytotoxic effects on HeLa, HepG2 and AGS cells, causing apoptosis. The results showed that Samultang-Gami may do so by regulating the expression of specific target molecules that promote efficient apoptotic cell death in a dose-dependent manner.

• Korean Journal of Materials Research
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• v.12 no.9
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• pp.761-766
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• 2002

Fine $LaPO_4$:Tb phosphor particles with spherical shape were prepared by spray pyrolysis. The influence of the precursor type of phosphorous such as ($NH_4$)$_2$$HPO_4$, $NH_4$$H_2$$PO_4$, ($NH_4$)$_3$$PO_4$ and $H_3$$PO_4$ on the morphology and brightness of particles was investigated. As-prepared particles by spray pyrolysis had spherical shape when ($NH_4$)$_2$ $HPO_4$ and $NH_4$$H_2$$PO_4$ were used as the precursor of phosphorous. The precursor type of phosphorous affected the photoluminescence intensity of $LaPO_4$:Tb phosphor particles, but not significant. With changing the content of activator(Tb) and excess of phosphorous, the optimal composition giving the highest photoluminescence intensity was found. The spherical morphology of prepared $LaPO_4$:Tb particles was completely maintained even after the posttreatment up to $1050^{\circ}C$. When the posttreatment temperature was over $1100^{\circ}C$, the particles did not have the spherical shape anymore. However, the highest photoluminescence intensity of prepared $LaPO_4$:Tb particles was obtained at $1050^{\circ}C$. The photoluminescence characteristics of prepared $_LaPO4$:Tb under the vacuum ultraviolet(VUV) illumination was comparable with that of the commercial $Zn_2$$V_4$:Mn and (La,Ce)PO$_4$:Tb phosphor particles. At the optimal condition, the decay time of prepared spherical $LaPO_4$:Tb phosphor particles was about 6.8ms.

• The Journal of Art Theory & Practice
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• no.6
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• pp.51-76
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• 2008

Nous obserbons dans le champs de l'art aujourd' hui, le changement radical provoquant $\'{e}$tant donn$\'{e}$ que le pouvoir du march$\'{e}$ de l'art s'augmente de plus en plus. C'est pour cela que le champ du discours de l'art n'est actuellement plus form$\'{e}$ par des notions esth$\`{e}$tiques artistiques, mais par celles qui sont r$\'{e}$serv$\'{e}$es au domaine de l'$\'{e}$conomie et du march$\'{e}$. Il n'est plus significatif de croire la valeur esth$\`{e}$tique de l'oeuvre d'art, puisque l'esth$\`{e}$tique elle-m$\^{e}$me ne fonctionne plus. Par contre, le syst$\`{e}$me de donner le prix $\`{a}$ l'oeuvre d'art fonctionne rigoureusement. En plus, cette situation s'aggrave $\'{e}$tant donn$\'{e}$ que la mondialisation du march$\'{e}$ de l'art s'installe avec rapidit$\'{e}$. Malgr$\'{e}$ la mondialisation de l'art, des gens qui habitent par exemple $\`{a}$ S$\'{e}$oul ne peuvent pas s' approcher facilement de ce qui se passe $\`{a}$ New York, le vrai centre de l'art contemporain. Dans cette situation, le champ de discours de l'art n'a pas d'autre solution de se r$\'{e}$tr$\'{e}$cir remaquablement et le sujet de discussion sur le grand art est remplac$\'{e}$ par celui du success de l'art. Cette recherche est arriv$\'{e}$e $\`{a}$ remarquer que le syst$\`{e}$me du foire internationale de l'art fonctionne comme une locomotive dans le march$\'{e}$ de l'art qui est le vrai dominateur de l'art contemporain. Aujourd'hui les grands clients du monde de l'art et les jeunes sp$\'{e}$ctateurs, les clients de l'avenir s'assemblent autour de quelques foires internationales r$\'{e}$put$\'{e}$s qui ont de l'autorit$\'{e}$. C'est ainsi que l'achat et la vante de l'oeuvres d'art est suffisamment mondialis$\'{e}$ et que le syst$\`{e}$me local du march$\'{e}$ est d$\'{e}$rang$\'{e}$ et s'$\'{e}$ffondr$\'{e}$gravement. Malgr$\'{e}$ la diff$\'{e}$rence significative, la majorit$\'{e}$ des galeries d'art lacaux s'oblige de suivre $\`{a}$ la suite du style du foire internationale de l'art. C'est la raison pour laquelle que cette recherche se fait une id$\'{e}$e nette que la prosp$\'{e}$rit$\'{e}$ actuelle du march$\'{e}$ de l'art n'est que la situation $\'{e}$conomique ou financi$\`{e}$re. A ce stade de la r$\'{e}$flexion, cette recherche arrivera $\`{a}$ poser une question primordiale ci-dessous: "Si l'art qu'on $\`{a}$ l'intention de proclamer ne serai plus possible de faire r$\'{e}$fl$\'{e}$chir sur la libert$\'{e}$ et la solidarit$\'{e}$ humain, la dignit$\'{e}$ de l'homme, cet art n'est plus autre chose que l'insignifiance. Au lieu de parcourir divers ph$\'{e}$nom$\`{e}$ne du march$\'{e}$ de l'art aujourd'hui, cette recherche fixera son attention sur la r$\'{e}$alit$\'{e}$ du foire internationales de l'art. Dans ce context, cette recherche sera compos$\'{e}$e par trois chapitres donc le premi$\`{e}$re essayera de r$\'{e}$pondre $\'{a}$ la question de son influence extraodinairement puissante. Le deuxi$\`{e}$me chapitre essayera d'analiser la r$\'{e}$alit$\'{e}$ et la source du pouvoir du foire internationale de l'art. Nous essayeront au troisi$\`{e}$me chapitre de configurer le point de vue critique qui permettra de bien comprendre notre sujet.

• Polymer(Korea)
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• v.32 no.3
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• pp.263-269
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• 2008

To develop carriers of hydrophobic anticancer agents based on chitosan, chitosan oligosaccharide lactate (COS) was chemically modified with lithocholic acid (LA) which is one of the bile acids as a hydrophobic group. The physicochemical properties of the lithocholic acid conjugated chitosan nanoparticles (COS-LA) were investigated using $^1H$-NMR spectroscopy, dynamic light scattering (DLS) and spectrofluorophotometer. COS-LA-paclitaxel (CLs-Tx) nanoparticles loading paclitaxel as an anticancer agent were prepared by a dialysis method and its loading efficiency was measured through HPLC. On the basis of DLS results, the estimated particle sizes of CLs-Tx were around 300 nm. Also, the critical micelle concentration (CMC) was proven to be dependent on the degree of substitution of lithocholic acid. It showed that the CLs-Tx has the superior potential for the application as a paclitaxel carrier.

• Resources Recycling
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• v.26 no.4
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• pp.79-87
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• 2017

Extraction and separation behaviors of La, Ce, Pr, Nd and Sm from light rare earth multi - component mixed solutions by Cyanex 572 were studied. As extractant concentration increased, the $pH_{50}$ values of all the five components decreased. When extractant concentration was larger than 0.6 M, the separation factor of La and Ce, Nd and Sm was higher than 10, while the separation factor between Ce and Pr, Pr and Nd was as low as 0.5~2.2. Addition of TBP to the 0.6 M Cyanex 572 had little synergistic effect on the phase separation rate and separation factor. From the analysis of experiment results, group separation of [La]/[Pr, Nd, Sm] and [Pr, Nd]/[Sm] could be possible, but in case of the group separation between [La, Ce] and [Pr, Nd] was not available because of the low separation factor between Ce and Pr.

• IMMUNE NETWORK
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• v.24 no.1
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• pp.8.1-8.17
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• 2024

Follicular helper T cells (Tfh) play a crucial role in generating high-affinity antibodies (Abs) and establishing immunological memory. Cytokines, among other functional molecules produced by Tfh, are central to germinal center (GC) reactions. This review focuses on the role of cytokines, including IL-21 and IL-4, in regulating B cell responses within the GC, such as differentiation, affinity maturation, and plasma cell development. Additionally, this review explores the impact of other cytokines like CXCL13, IL-10, IL-9, and IL-2 on GC responses and their potential involvement in autoimmune diseases, allergies, and cancer. This review highlights contributions of Tfh-derived cytokines to both protective immunity and immunopathology across a spectrum of diseases. A deeper understanding of Tfh cytokine biology holds promise for insights into biomedical conditions.

• Proceedings of the Korea Crystallographic Association Conference
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• 2007.11a
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• pp.48-48
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• 2007

• Proceedings of the KSCN Conference
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• 2005.04a
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• pp.109-110
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• 2005

• Proceedings of the Zoological Society Korea Conference
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• 2000.04a
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• pp.86.1-86
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• 2000

No Abstract, See Full Text