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121.
In this Letter we study electron interference in nanotube loops. The conductance as a function of the applied voltage is shown to oscillate due to interference between electron beams traversing the loop in two opposite directions, with slightly different velocities. The period of these oscillations with respect to the gate voltage, as well as the temperatures required for the effect to appear, are shown to be much larger than those of the related Fabry-Perot interference. We calculate interaction effects on the period of the oscillations, and show that even though interactions destroy much of the near degeneracy of velocities in the symmetric spin channel, the slow interference effects survive. 相似文献
122.
Development of Imidazoline‐2‐Thiones Based Two‐Photon Fluorescence Probes for Imaging Hypochlorite Generation in a Co‐Culture System
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Dr. Qingling Xu Cheol Ho Heo Gyoungmi Kim Hyo Won Lee Prof. Hwan Myung Kim Prof. Juyoung Yoon 《Angewandte Chemie (International ed. in English)》2015,54(16):4890-4894
We designed and prepared the imidazoline‐2‐thione containing OCl? probes, PIS and NIS , which operate through specific reactions with OCl? that yield corresponding fluorescent imidazolium ions. Importantly, we demonstrated that PIS can be employed to image OCl? generation in macrophages in a co‐culture system. We have also employed two‐photon microscopy and PIS to image OCl? in live cells and tissues, indicating that this probe could have wide biological applications. 相似文献
123.
Multivalent Polymer Nanocomplex Targeting Endosomal Receptor of Immune Cells for Enhanced Antitumor and Systemic Memory Response
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Sun‐Young Kim Min Beom Heo Dr. Geum‐Sook Hwang Youngae Jung Dr. Do Yeol Choi Prof. Dr. Yeong‐Min Park Prof. Dr. Yong Taik Lim 《Angewandte Chemie (International ed. in English)》2015,54(28):8139-8143
We have designed and synthesized linear polymer‐based nanoconjugates and nanocomplexes bearing multivalent immunostimulatory ligands and also demonstrated that the synthetic multivalent nanocomplexes led to an enhanced stimulation of immune cells in vitro and antitumor and systemic immune memory response in vivo. We have developed hyaluronic acid (HA)‐based multivalent nanoconjugates and nanocomplexes for enhanced immunostimulation through the combination of multivalent immune adjuvants with CpG ODNs (as a TLR9 ligand) and cationic poly(L ‐lysine) (PLL; for the enhancement of cellular uptake). The multivalent HA‐CpG nanoconjugate efficiently stimulated the antigen‐presenting cells and the multivalent PLL/HA‐CpG nanocomplex also led to an enhanced cellular uptake as well as continuous stimulation of endosomal TLR9. The mice vaccinated with dendritic cells treated with the multivalent nanocomplex exhibited tumor growth inhibition as well as a strong antitumor memory response. 相似文献
124.
A phase-field model for modeling the diffusional processes in an elastically anisotropic polycrystalline binary solid solution is described. The elastic interactions due to coherency elastic strain are incorporated by solving the mechanical equilibrium equation using an iterative-perturbation scheme taking into account elastic modulus inhomogeneity stemming from different grain orientations. We studied the precipitate interactions among precipitates across a grain boundary and grain boundary segregation–precipitate interactions. It was shown that the local pressure field from one coherent precipitate influences the shape of precipitates in other grains. The local pressure distribution due to primary coherent precipitates near the grain boundary leads to inhomogeneous solute distribution along the grain boundary, resulting in non-uniform distribution of secondary nuclei at the grain boundary. 相似文献
125.
Natural convection heat transfer phenomena on horizontal cylinders were investigated experimentally in order to explore the
applicability of analogy experimental method using the copper electroplating system and to visualize the local heat transfer
depending on the angular position and the diameter of the horizontal cylinder. The diameters of the cylinders are varied from
0.01 to 0.15 m, which correspond to the Rayleigh numbers of 1.73 × 107–5.69 × 1011. The measured mass transfer coefficients show good agreements with the existing heat transfer correlations. The patterns
of copper plated on the aluminum cathodes for various Rayleigh numbers reveal and visualize the local heat transfer depending
on the angular position and show good agreement with the works of Kitamura et al. The hydrogen bubbles produced at higher
applied potential visualize the plumes appeared on top region of the cylinders. 相似文献
126.
Kim SK Li Y Abrol R Heo J Goddard WA 《Journal of chemical information and modeling》2011,51(2):420-433
Subtype 2 serotonin (5-hydroxytryptamine, 5-HT) receptors are major drug targets for schizophrenia, feeding disorders, perception, depression, migraines, hypertension, anxiety, hallucinogens, and gastrointestinal dysfunctions. (1) We report here the predicted structure of 5-HT2B and 5-HT2C receptors bound to highly potent and selective 5-HT2B antagonist PRX-08066 3, (pKi: 30 nM), including the key binding residues [V103 (2.53), L132 (3.29), V190 (4.60), and L347 (6.58)] determining the selectivity of binding to 5-HT2B over 5-HT2A. We also report structures of the endogenous agonist (5-HT) and a HT2B selective antagonist 2 (1-methyl-1-1,6,7,8-tetrahydro-pyrrolo[2,3-g]quinoline-5-carboxylic acid pyridine-3-ylamide). We examine the dynamics for the agonist- and antagonist-bound HT2B receptors in explicit membrane and water finding dramatically different patterns of water migration into the NPxxY motif and the binding site that correlates with the stability of ionic locks in the D(E)RY region. 相似文献
127.
Coordination polymer nanorods are synthesized from the hexagonal 3D structure of Fe-MIL-88B. Subsequently, hematite (α-Fe(2)O(3)) and magnetite (Fe(3)O(4)) nanorods are selectively prepared by controlling the calcination conditions of coordination polymer nanorods. 相似文献
128.
Protein–ligand docking techniques are one of the essential tools for structure‐based drug design. Two major components of a successful docking program are an efficient search method and an accurate scoring function. In this work, a new docking method called LigDockCSA is developed by using a powerful global optimization technique, conformational space annealing (CSA), and a scoring function that combines the AutoDock energy and the piecewise linear potential (PLP) torsion energy. It is shown that the CSA search method can find lower energy binding poses than the Lamarckian genetic algorithm of AutoDock. However, lower‐energy solutions CSA produced with the AutoDock energy were often less native‐like. The loophole in the AutoDock energy was fixed by adding a torsional energy term, and the CSA search on the refined energy function is shown to improve the docking performance. The performance of LigDockCSA was tested on the Astex diverse set which consists of 85 protein–ligand complexes. LigDockCSA finds the best scoring poses within 2 Å root‐mean‐square deviation (RMSD) from the native structures for 84.7% of the test cases, compared to 81.7% for AutoDock and 80.5% for GOLD. The results improve further to 89.4% by incorporating the conformational entropy. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011 相似文献
129.
Min Ku Jeon Jae Won Lee Kweon Ho Kang Geun Il Park Chang Hwa Lee Jae Hwan Yang Chul Min Heo 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):417-422
Nitrofurantoin (NFN) radiolabeling with technetium-99m (99mTc) was investigated using different concentration of the NFN, sodium pertechnetate (Na99mTcO4), reducing agent (SnCl2) at different pH ranges (5.1–6.00). The suitability of the 99mTc-NFN was evaluated in terms of the radiochemical purity (RCP) yield, in vitro stability in saline, serum, in vitro binding
with E. coli, biodistribution in E. coli infected model rat (ERT), and scintigraphic accuracy in E. coli infected model rabbit (EBT). The superlative radiochemical succumb at 2.5 mg NFN, 125 μL of SnCl2 (1 μg/μL in 0.01 N HCl), 2.5 mCi of Na99mTcO4, at pH 5.2 at 30, 60, 90, and 120 min after reconstitution was 64.50 ± 0.11, 97.50 ± 0.16, 94.25 ± 0.10, 92.15 ± 0.14 and
90.75 ± 0.0.13%. The complex was found stable in saline and serum for 90% up to 120 min and showed 50–65% in vitro binding
with E. coli. The absorption of the 99mTc-NFN, primarily at E. Coli infected (ECT) muscle of ERT was lower but after 60 min it went up to 7.25 ± 0.17%. The absorption in the blood, liver, spleen,
stomach, intestines, inflamed muscle (N.T1) and normal muscle (N.T2) went down while in the kidney and urine it went up with
time. The ratio of the ECT/N.T1 was 7:1 and N.T2/N.T1 was 2:1. The Whole Body Static (WBS) imaging of the ERB confirmed the
suitability of the 99mTc-NFN as radiotracer. The superlative radiochemical succumb, significant in vitro stability in saline and serum, in vitro
binding with E. coli, ideal biodistribution and scintigraphic accuracy confirmed the viability of the 99mTc-NFN as radiotracer for infection. 相似文献
130.
Oocyte cryopreservation has become an essential tool in the treatment of infertility by preserving oocytes for women undergoing chemotherapy. However, despite recent advances, pregnancy rates from all cryopreserved oocytes remain low. The inevitable use of the cryoprotectants (CPAs) during preservation affects the viability of the preserved oocytes and pregnancy rates either through CPA toxicity or osmotic injury. Current protocols attempt to reduce CPA toxicity by minimizing CPA concentrations, or by minimizing the volume changes via the step-wise addition of CPAs to the cells. Although the step-wise addition decreases osmotic shock to oocytes, it unfortunately increases toxic injuries due to the long exposure times to CPAs. To address limitations of current protocols and to rationally design protocols that minimize the exposure to CPAs, we developed a microfluidic device for the quantitative measurements of oocyte volume during various CPA loading protocols. We spatially secured a single oocyte on the microfluidic device, created precisely controlled continuous CPA profiles (step-wise, linear and complex) for the addition of CPAs to the oocyte and measured the oocyte volumetric response to each profile. With both linear and complex profiles, we were able to load 1.5 M propanediol to oocytes in less than 15 min and with a volumetric change of less than 10%. Thus, we believe this single oocyte analysis technology will eventually help future advances in assisted reproductive technologies and fertility preservation. 相似文献