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121.
Junoh Kim Jongwon Shim Yong‐Jin Kim Kookheon Char Kyung‐Do Suh Jin‐Woong Kim 《Macromolecular bioscience》2010,10(10):1171-1176
This study reports a facile and practical means to non‐invasively deliver biologically active ingredients through the skin using polymer‐based nanocarriers. For this, polymer nanocapsules were fabricated with different surface charges as well as glass transition temperatures and we observed their ability to deliver the encapsulated active ingredient, coenzyme Q10, through the skin layer. Direct imaging of a probe molecule, Nile Red, and a matrix polymer labeled with fluorescence moiety, Lucifer Yellow, allowed us to demonstrate that the probe molecule readily permeates into the deep skin, while the matrix polymer stays in the stratum corneum layer due to electrostatic interactions. Quantitative characterization of the penetrating amount of coenzyme Q10 using the Frantz cell method proved that, to achieve improved delivery efficiency, the nanocapsule should have a low glass transition temperature as well as positive surface charges.
122.
123.
Jin Seok Woo Chung-Hyun Cho Do Han Kim Eun Hui Lee 《Experimental & molecular medicine》2010,42(9):614-627
During membrane depolarization associated with skeletal excitation-contraction (EC) coupling, dihydropyridine receptor [DHPR, a L-type Ca2+ channel in the transverse (t)-tubule membrane] undergoes conformational changes that are transmitted to ryanodine receptor 1 [RyR1, an internal Ca2+-release channel in the sarcoplasmic reticulum (SR) membrane] causing Ca2+ release from the SR. Canonical-type transient receptor potential cation channel 3 (TRPC3), an extracellular Ca2+-entry channel in the t-tubule and plasma membrane, is required for full-gain of skeletal EC coupling. To examine additional role(s) for TRPC3 in skeletal muscle other than mediation of EC coupling, in the present study, we created a stable myoblast line with reduced TRPC3 expression and without α1SDHPR (MDG/TRPC3 KD myoblast) by knock-down of TRPC3 in α1SDHPR-null muscular dysgenic (MDG) myoblasts using retrovirus-delivered small interference RNAs in order to eliminate any DHPR-associated EC coupling-related events. Unlike wild-type or α1SDHPR-null MDG myoblasts, MDG/TRPC3 KD myoblasts exhibited dramatic changes in cellular morphology (e.g., unusual expansion of both cell volume and the plasma membrane, and multi-nuclei) and failed to differentiate into myotubes possibly due to increased Ca2+ content in the SR. These results suggest that TRPC3 plays an important role in the maintenance of skeletal muscle myoblasts and myotubes. 相似文献
124.
Haladhara Naik Guinyun Kim Ashok Goswami Sarbjit Singh Vijay Kumar Manchanda Devesh Raj Srinivasan Ganesan Young Do Oh Hee-Seock Lee Kyung Sook Kim Man-Woo Lee Moo-Hyun Cho In Soo Ko Won Namkung 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(2):439-445
The mass–yield distributions of various fission products have been determined in the 50-, 60- and 70-MeV end point bremsstrahlung induced fission of natPb using off-line γ-ray spectrometric technique in the electron linac at Pohang Accelerator Laboratory, Korea. The mass–yield distributions are symmetric with average mass of 102.34, 102.25 and 102.03 and FWHM of 21, 22 and 23 mass unit, respectively. From the present data and literature data in the 50–85 MeV bremsstrahlung induced fission of 209Bi the following observations were obtained: (i) The average masses of the yield distributions in the 50–85 MeV bremsstrahlung induced fission of natPb and 209Bi are around 102.25 ± 0.25 and 103 ± 0.5, respectively. (ii) The FWHM of the mass–yield distributions increases from about 21 mass units at 50 MeV to 23 mass units at 70–85 MeV, which is explained from the point of increase in multi-chance fission probability with increasing excitation energy. (iii) Within the bremsstrahlung energy range of 50–85 MeV, the role of nuclear structure effect in the mass–yield distribution was observed in the photo-fission of 209Bi, whereas it was not seen in case of natPb. This may be due to the presence of so many isotopes in natPb unlike mono-isotopic 209Bi. 相似文献
125.
In this study, the supersymmetric Wentzel-Kramers-Brillouin (SWKB) approximation method has been discussed in detail. The entire bound state energy eigenvalues and the ground state wave function of the q-deformed potentials such as Pöschl-Teller and Rosen-Morse potentials have been obtained by SWKB approximation. We have shown that our results are in complete agreement with the results obtained by E?rifes et al. (Physica Scripta 59:90–94, 1999; Physica Scripta 60:195–198, 1999). 相似文献
126.
A single-mode fiber (SMF) acousto-optic tunable filter (AOTF) with a tuning range of more than 300 nm is demonstrated. The SMF used in the experiment has a ring of symmetric holes within the cladding, which causes a larger mode-index difference between the first and the second higher-order antisymmetric modes than those of a conventional SMF. As a result, the difference in beatlengths between the core mode and the higher-order modes is highly increased, which makes it possible for the SMF AOTF to exhibit a single resonance peak in the transmission spectrum over the wavelength range of 1.3-1.6 μm for given acoustic frequencies of 3.1-3.8 MHz. 相似文献
127.
Se Hoon KimJin Woo Kim Tae Sun JoYoung Do Kim 《Journal of magnetism and magnetic materials》2011,323(22):2851-2854
The fabrication of Nd11Dy4Fe76.5TM2.5B6 (TM=Co, Cu, Al, and Nb: at%) sintered magnets via a two-step sintering process was demonstrated. A densification of greater than 99% was achieved using the two-step sintering of the Nd-Fe-B powder. This process produced a sample with an average grain size of 6.2 μm in the Nd2Fe14B phase, resulting in an enhancement of the coercivity compared to that of the isothermally sintered sample. The suppression of grain growth was considered to be affected by the relatively low temperature during the two-step sintering and by the presence of a B-rich phase at the triple junction. Consequently, the two-step sintering process led to suppression of grain growth and a uniform grain size distribution, which resulted in improved magnetic properties, in particular in the intrinsic coercivity. 相似文献
128.
Optimality conditions for weak efficient, global efficient and efficient solutions of vector variational inequalities with constraints defined by equality, cone and set constraints are derived. Under various constraint qualifications, necessary optimality conditions for weak efficient, global efficient and efficient solutions in terms of the Clarke and Michel–Penot subdifferentials are established. With assumptions on quasiconvexity of constraint functions sufficient optimality conditions are also given. 相似文献
129.
The reaction of 2‐(2‐bromoethyl)‐1,3‐dioxane with 1‐alkylbenzimidazole derivatives results in the formation of the new benzimidazolium salts (1). The reaction of Pd(OAc)2 with 1,3‐dialkylbenzimidazolium salts (1a–c) yields palladium N‐heterocyclic carbene (NHC) complexes (2a–c). All synthesized compounds were characterized by 1H NMR, 13 C NMR, IR and elemental analysis techniques which support the proposed structures. As catalysts, these new palladium complexes offer a simple and efficient methodology for the synthesis of triarylamines and secondary amines from anilines and amines and in a single step with potassium tertiary butoxide as a base. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
130.
Seon‐Kyoung Son Yoon‐Suk Choi Woo‐Hyung Lee Yongtaek Hong Jae‐Ryoung Kim Won‐Suk Shin Sang‐Jin Moon Do‐Hoon Hwang In‐Nam Kang 《Journal of polymer science. Part A, Polymer chemistry》2010,48(3):635-646
A series of new phenothiazylene vinylene‐based semiconducting polymers, poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene] ( P1 ), poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene‐alt‐1,4‐phenylene vinylene] ( P2 ), and poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene‐alt‐2,5‐thienylene vinylene] ( P3 ), have been synthesized via a Horner‐Emmons reaction. FTIR and 1H NMR spectroscopies confirmed that the configurations of the vinylene groups in the polymers were all‐trans (E). The weight‐averaged molecular weights (Mw) of P1 , P2 , and P3 were found to be 27,000, 22,000, and 29,000, with polydispersity indices of 1.91, 2.05, and 2.25, respectively. The thermograms for P1 , P2 , and P3 each contained only a broad glass transition, at 129, 167, and 155 °C, respectively, without the observation of melting features. UV–visible absorption spectra of the polymers showed two strong absorption bands in the ranges 315–370 nm and 450–500 nm, which arose from absorptions of the phenothiazine segments and the conjugated main chains. Solution‐processed field‐effect transistors fabricated from these polymers showed p‐type organic thin‐film transistor characteristics. The field‐effect mobilities of P1 , P2 , and P3 were measured to be 1.0 × 10?4, 3.6 × 10?5, and 1.0 × 10?3 cm2 V?1 s?1, respectively, and the on/off ratios were in the order of 102 for P1 and P2 , and 103 for P3 . Atomic force microscopy and X‐ray diffraction analysis of thin films of the polymers show that they have amorphous structures. A photovoltaic device in which a P3 /PC71BM (1/5) blend film was used as the active layer exhibited an open‐circuit voltage (VOC) of 0.42 V, a short circuit current (JSC) of 5.17 mA cm?2, a fill factor of 0.35, and a power conversion efficiency of 0.76% under AM 1.5 G (100 mW cm?2) illumination. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 635–646, 2010 相似文献