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81.
Fraley AW Pons B Dalkara D Nullans G Behr JP Zuber G 《Journal of the American Chemical Society》2006,128(33):10763-10771
Oligonucleotide delivery is a crucial issue for therapeutical purposes and is often addressed by conjugation to short cationic peptides although with controversial results. To further examine this mechanism, a 15-mer anionic oligonucleotide was conjugated to a cationic peptide in order to obtain a diblock compound with an overall positive charge with aggregation properties. These microaggregates were efficiently internalized in cells via the expeditious pathway used by commercial gene delivery systems. Moreover, stability of the duplex formed with the complementary sequence increased without inhibiting oligonucleotide enzyme recognition as shown by the properties of the conjugate to prime chain elongation by Taq DNA polymerase in a linear amplification/sequencing process. 相似文献
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Synthesis of two-component organogelation system was performed very easy and concise manner from Nε-palmitoyl-L-lysine ethyl ester and Nε-miristoyl-L-lysine ethyl ester in which they were used as base component and N-lauroyl-L-amino acids (amino acids:, alanine, leucine and phenylalanine as acid components.). And their organogelation properties were examined in different pharmaceutical fluids such as liquid paraffin, fatty acid ethyl, and isopropyl esters. In this way, gelation efficiency was ascertained variations of alkanoyl moieties and combination of different amino acids in the gelator structures. Characterization of gelators was performed via thermal measurement such as Tg and gel–sol enthalpy change; SEM and FTIR as optical methods. 相似文献
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In this study, experimental measurements have been made on the batch adsorption of cadmium and lead ions from aqueous solutions using poly(guanidine modified 2‐acrylamido‐2‐methylpropan sulfonic acid/acrylic acid/N‐vinylpyrrolidone/2‐Hydroxyethyl methacrylate), P(AMPSG/AAc/NVP/HEMA) hydrogels. The guanidyl end group bearing AMPSG monomer was synthesized from the reaction of AMPS and guanidine. The hydrogels were prepared by UV‐curing technique. The morphology of the dry H10‐hydrogel sample was examined by SEM. The influence of the uptake conditions, such as pH, functional monomer per cent, contact time, initial feed concentration, and foreign metal ions on the metal ion binding capacity of hydrogel, was also tested. The selectivity of the hydrogel toward the different metal ions tested was Hg(II) > Pb(II) > Au(III) > Cd(II). The adsorption isotherm models were applied to the experimental data, and it was seen that the Langmuir isotherm model was the best fit for the adsorption of Cd(II) and Pb(II) ions on P(AMPSG/AAc/NVP/HEMA) hydrogel. It was found that adsorbed lead and cadmium ions on P(AMPSG/AAc/NVP/HEMA) hydrogel can be effectively desorbed by acid leaching and the regenerated P(AMPSG/AAc/NVP/HEMA) hydrogel can be reused almost five times less without any loss of adsorption capacity. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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The static conversion from brick-and-mortar retailing to the hybrid click-and-mortar business model is studied from the perspective of distribution logistics. Retailers run warehouses and brick-and-mortar stores to meet the demand of their walk-in customers. When they decide to operate on the Web as an e-tailer, also click-and-mortar stores are needed which can serve both walk-in and online customers. While the distance between home and the nearest open store is used as a proxy measure for walk-in customers, a quality of service (QoS) guarantee for online customers is timely delivery of their orders. We describe and solve a static location-routing based problem for companies that embrace the clicks-and-bricks strategy in their retail operations. An augmented Lagrangian relaxation method embedded in a subgradient optimization procedure generates lower bounds, whereas a heuristic method finds feasible solutions. The performance of the Lagrangian-based solution method is tested on a number of randomly generated test problems. 相似文献
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Ultrahigh-Q microtoroids on a chip are applied as replication masters to demonstrate replica-molded high-Q microresonator arrays. Replica Q factors are nearly material loss limited, affirming the integrity of the replication process, and are as high as 5 x 10(6), or nearly a factor of 40 greater than previous polymer-based devices. Because the molding process is nondestructive, both the master and the molds can be reused. Additionally, by using a novel optical polymer (Vicast), we demonstrate storage of high-Q microresonators in the mold for weeks, providing a method to preserve the whispering-gallery Q factor. 相似文献
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The temperature dependence of the monoclinic lattice constants in the two smectic phases, S1G and S2G, of HxBPA, has been obtained from X-ray diffraction data, in the temperature range 300 K < T < 240 K. The variation of b (unique axis) is consistent with the chain ordering in the S2G phase indicated by Raman and NMR measurements. 相似文献