• Applied Chemistry for Engineering
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• v.34 no.6
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• pp.633-639
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• 2023

We synthesized 2-(10-methyl-10H-phenothiazin-3-yl)-5-phenyl-1,3,4-oxadiazole (MPPO) and 5,5-(10-methyl-10H-phenothiazin-3,7-diyl)-bis-(2-phenyl-1,3,4-oxadiazole) (DPPO). MPPO has both electron-donating and electron-accepting substituents with asymmetric molecular geometry. By incorporating one extra electron-accepting group into MPPO, we created a symmetric molecule, which is DPPO. The optical and electrochemical properties of these compounds were measured. The lowest unoccupied molecular orbital (LUMO) level of DPPO was lower than that of MPPO. The excited-state dipole moment of DPPO, with symmetric geometry, was calculated to be 4.1 Debye, whereas MPPO, with asymmetric geometry, had a value of 7.0 Debye. The charge-carrier mobility of both compounds was similar. We fabricated non-doped organic light-emitting diodes (OLEDs) using D-A type molecules as an emitting layer. The current efficiency of the DPPO-based device was 7.8 cd/A, and the external quantum efficiency was 2.4% at 100 cd/m², demonstrating significantly improved performance compared to the MPPO-based device. The photophysical and electroluminescence (EL) characteristics of the two D-A type molecules showed that molecular symmetry, as well as the lowered LUMO level of DPPO, played critical roles in the enhancement of EL performance.

• Biomolecules & Therapeutics
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• v.10 no.2
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• pp.104-113
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• 2002

The effects of enzyme inhibitors and penetration enhancers on the permeation of leucine enkephalin (Leu-Enk) and its synthetic analog, [${D-ala}^2$]-leucine enkephalinamide (YAGFL) across the nasal, rectal and vaginal mucosae were evaluated. Enzyme inhibitors and penetration enhancers employed for Leu-Enk permeation study were amastatin(AM), thimerosal(TM) and ethylenediaminetetraacetic acid disodium salt(EDTA), and sodium taurodihydrofusidate (STDHF). Those for YAGFL permeation study were TM, benzalkonium chloride(BC) and EDTA, and STDHF, sodium deoxycholate(SDC), sodium glycholate(SGC), glycyrrhizic acid ammonium salt (GAA), L-$\alpha$-Iysophosphatidylcholine(LPC) and mixed micelle (MM, STDHF: linoleic acid = 15 mM : 5 mM). The addition of TM alone on the donor and receptor solutions for Leu-Enk permeation study across all the three kinds of mucosae failed to inhibit the degradation; it completely degraded in 6 hrs, and no permeation occurred. However, with addition of three kinds of inhibitors together, the fluxes across nasal, rectal and vaginal mucosae were $\20.7{pm}2.5$>/TEX>,$\0.3{pm}0.05$>/TEX> and $\1.4{pm}0.5$ $\mu$\mid$textrm{m}$/$\textrm{cm}^2$/hr, respectively. Moreover, the addition of STDHF in the presence of the above three inhibitors enhanced permeation across nasal, rectal and vaginal mucosae 1.3, 15 and 1.3 times, respectively. YhGFL also degraded in the donor and receptor solutions rapidly as time went. With mixed inhibitors of TM and EDTA, the percents of YAGFL remaining in the donor solutions facing nasal, rectal and vaginal mucosae were 69.7, 69.8 and 79.8%, respectively; the percent permeated increased to 10, 2.1 and 5.7%, respectively. The addition of STDHF in the presence of either BC/EDTA or TW/EDTA increased the permeation 2.2, 11.0 and 2.9 times, and 2.21, 14.0 and 2.7 times for nasal, rectal and vaginal mucosae, respectively. With SDC, SGC, GAA, LPC ud MM in the presence of TM/EDTA increased permeation; especially, they increased permeation across vaginal mucosae effectively, and the enhancement factors were 12.5, 7.6, 8.7, 5.7 and 5.5, respectively. The degradation extent of YAGFL was correlated with protein concentrations in the epidermal and serosal extracts. The flux of YAGFL across nasal mucosa increased dose-dependently.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.790-799
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• 1997

Aegilops genus is known to include the donor species of the Band D genome of the bread wheat(ABD). An effort to establish a better strategy for phylogenetic relationships about Aegilops polyploids by AFLPs(Amplified Fragment Length Polymorphisms) was conducted using the 19 Aegilops sPP. and T. aestivum. The 207 polymorphic bands from the amplified products on the 6% acrylamide denaturing sequencing gels were obtained with the 7 AFLP primer combinations, and used to account for the genetic similarities and cluster analysis using NTSYS program. According to the genome analysis, the $M^h$-genome of Ae. heldreichii was estimated as an intermediate genome between the M-genome of Ae. comosa and N-genome of Ae. uniaristata and supposed to be incorporated in the establishing process of UM-genome as a possible diploid donor. And Ae. ventricosa(DN) was more close to Ae. umbellulata(U) than Ae. squarrosa(D). The close relationship between Ae. squarrosa and T. aestivum was perceived as a diploid donor of D-genome. As for the polyploid species, hexaploid Ae. triaristata was more closely related to Ae. columnaris rather than tetraploid Ae. triaristata. The clustered groups were, basically same to the previous Gihara's sections based on phenotypes and pairing analysis of interspecific hybrids. AFLP was evaluated as an efficient and powerful method in the genome evaluation of closely related species.

• Korean Journal of Animal Reproduction
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• v.20 no.4
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• pp.459-465
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• 1997

The present study was undertaken to determine the effect of NT time on the rate of fusion a and suhseguent development In vitro and determine the optimal strength and duration of DC pulse for electrofusion of IVF donor embryo nuclei and IVM recipient oocytes. The recipient oocytes were enucleated 25 ~ 2Sh after IVM and further cultured for 18 ~ 20h prior to fusion for oocyte aging. IVF embryos as donor nuclei were C co cultured with BOEC for 16- to 32-cell stage development. The transfer time of donor bIas tomeres was 1~3h post-enucleation in early NT group and 1 ~ 18h post-enucleation in late NT group, respectively and fusion was performed 43~4Sh post-IVM. The fusion rate did not differ between the early NT and late NT group, but the rate of cleavage and 8- to 16-cell stage embryos in the late NT group was more higher than that in the early NT group. The fusion, cleavage and M+B development was high from O.7SkV /cm DC than from 1.0kV /cm DC voltage, resulting in 17.6% M+B from 0.75kV /cm DC voltage. No difference in fusion rate was among pulse durations, but 50 and 70 usec pulse duration showed slight high cleavage and M + B d development. The results indicate that the best NT time of IVF donor blastomeres into the enucleated oocytes was 42~44 post-IVM and the most suitable condition for electrofusion was a single 0.7SkV /cm DC voltage for SO~70$\mu$sec.

• Journal of Embryo Transfer
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• v.10 no.1
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• pp.73-82
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• 1995

large scale production of cloned embryos requires the technology of multiple generation nuclear transplantation(NT) using NT embryos as the subsequent donor nuclei. The purposes of this study were producing the second generation cloned rabbit embryos, and also to determine the electrofusion rate and in vitro developmental potential comparatively in the cloned embryos of the first and second NT generation. The embryos of 16-cell stage were collected from the mated does by flushing oviducts with Dulbecco's phosphate buffered saline(D-PBS) containing 10% fetal calf serum(FCS) at 47 hours after hCG injection In the first generation NT, the nuclear donor embryos were synchronized in the phase of Gi /S transition of 32-cell stage. The first generation NT embryos which were developed to 8-cell were synchronized in Gi /S transition phase of the following 16-cell stage and used as donor nuclei for second generation Synchronization of the cell cycle of blastomeres was induced, first, using an inhibitor of microtuble polymerization, colcemid for 10 hours to arrest blastomeres in M phase, and secondly, using a DNA synthesis inhibitor, aphidicolin for 1.5 to 2 hours to arrest them in Gi /S transition boundary. The recipient cytoplasms were obtained by removing the nucleus and the first polar body from the oocytes collected at 14 hours after hCG injection. The separated donor blastomeres were injected into the enucleated recipient oocytes by micromanipulation and were electrofused by electrical stimulation of three pulses for 60 $\mu$sec at 1.25 kV /cm in 0.28 M rnannitol solution The fused oocytes were co-cultured with a monolayer of rabbit oviductal epithelial cells in M-199 solution containing 10% FCS for 120 hours at 39$^{\circ}C$ in a 5% $CO_2$ incubator. Following in vitro culture of the first and second generation cloned embryos to blastocyst stage, they were stained with Hoechst 33342 dye for counting the number of blastomeres by fluorescence microscopy. The results obtained were summarized as follows: 1. The electrofusion rate was found to be similar as 79.4 and 91.5% in the first and second generation NT rabbit embryos, respectively. 2. The in vitro developmental potential to blastocyst stage of the second generation NT embryos (23.3%) was found significantly(p<0.05) lower, compared with that of the first generation NT embryos (56.8%). 3. The mean blastomeres counts of embryos developed to blastosyst stage following in vitro culture for 120 hours and also their daily cell cycles during the culture period were decreased significantly (p<0.05) to 104.3 cells and 1.33 cylces in the second NT generation, compoared with 210.4 cells and 1.54 cycles in the first NT generation, respectively.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.9
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• pp.43-49
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• 1997

The dependence of the electrical properties in planar MQW - APD & pn, and p - i - n photodiode implanted with oxygen on the annealing emperatures and ion dose has been investigated. The oxygen implantation was performed for inter-device isolation. The leakage current of as-impanted p-i-n photodiode obtained was less than 50 nA. An annelaing temperature dependence study shows an abrupt increase of leakge current at 600.deg.C for all devices under study. This indicates that donor complex centers introduced by the chemical activity of oxygen increase with increasing annelaing temperatures. Furthermore, leakage current was highly correlated with oxygen dose due to th eimplanted related defects.

• Journal of Photoscience
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• v.8 no.2
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• pp.43-53
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• 2001

a, a parameter that describes how effectively photoinactivated PS II units protect their functional neighbours; car, carotenoids; ΔpH, transthylakoid pH difference; D1 protein, psbA gene product in the PS II reaction centre; f, functional fraction of PS II: F$\_$v//F$\_$m/, the ratio of variable to maximum chlorophyll a fluorescence; k$\_$d/, rate coefficient for degradation of D1 protein; k$\_$i/ and k$\_$r/, rate coefficient for photoinactivation and repair of PS II, respectively; NADP+, oxidized nicontinamide adenine dinucleotide phosphate; P680, the primary electron donor in the PSII reaction centre; Ph, pheophytin; PS, photosystem; Q$\_$A/, first quinone acceptor of an electron in PS II; R$\_$s/, the gross rate of D1 protein synthesis.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1315-1319
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• 2008

A trisaccharide, 6d-Altro-Hepp$\alpha$ (1$\rightarrow$3) GlcNAc$\beta$ (1$\rightarrow$3) Gal$\alpha$ (1$\rightarrow$$OCH_2CH_2N_3$, as an O-antigenic repeating unit of Campylobacter jejuni serotypes O:23 and O:36, was synthesized. Coupling of the 6d-altro-Hepp$\alpha$ (1$\rightarrow$3) GlcNAc$\beta$ (1$\rightarrow$SEt donor with Gal$\alpha$ (1${\rightarrow}OCH_2CH_2Cl$ acceptor in the presence of NIS-TfOH promoter afforded the trisaccharide having the $\beta$ (1$\rightarrow$3) Gal linkage. $\beta$ -Stereospecificity and the desired regioselectivity for the 3-OH Gal are obtained. Subsequent hydrogenation, acetylation, azide displacement, hydrazinolysis, Nacetylation, and finally deacetylation furnished the title trisaccharide hapten for further glycoconjugation.

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.766-771
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• 1994

A number of molybdenum(VI), -(V), and -(IV) oxo complexes with S-methyl 3-(2-hydroxyphenyl)methylenedithiocarbazate and its derivatives as the ONS-donor metal-binding substrate are synthesized. The Mo(VI)-dioxo complexes are cis-dioxo Mo$O_2$L(D), where D is solvent molecules such as MeOH, DMF, Py(pyridine), DMSO, and ${\gamma}$-Pic(${\gamma}$-picoline). The Mo(V)-oxo complexes are of the type (PyH)[MoO(NCS$)_2$L] with an octahedral geometry. The Mo(IV)-oxo complexes, MoOL are derived from corresponding Mo(VI)-dioxo complexes by oxo abstraction with PP$h_3$. The complexes are characterized by IR, $^1$H-NMR, UV-Vis spectroscopy and cyclic voltammetry. On the basis of ligand displacement reaction, the qualitative order of D binding for Mo$O_2$L(D) complexes is also discussed.

• Polymer(Korea)
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• v.25 no.1
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• pp.63-70
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• 2001

The objective of this study was to investigate the effect of cure type on the processing and physical properties under conditions of similar stress-strain properties. On the carbon black filled natural rubber(NR) based compound, the induction time decreased, but the cure rate became fast with increasing loading of sulfur donor agent. Tensile strength was little affected on the curing type. However, elongation generally decreased with increasing accelerator. Effect of cure type on the blow-out properties was followings: CV