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51.
Chikungunya is an infectious disease caused by mosquito-transmitted chikungunya virus (CHIKV). It was reported that NS1 and E2 siRNAs administration demonstrated CHIKV inhibition in in vitro as well as in vivo systems. Cationic lipids are promising for designing safe non-viral vectors and are beneficial in treating chikungunya. In this study, nanodelivery systems (hybrid polymeric/solid lipid nanoparticles) using cationic lipids (stearylamine, C9 lipid, and dioctadecylamine) and polymers (branched PEI-g-PEG -PEG) were prepared, characterized, and complexed with siRNA. The four developed delivery systems (F1, F2, F3, and F4) were assessed for stability and potential toxicities against CHIKV. In comparison to the other nanodelivery systems, F4 containing stearylamine (Octadecylamine; ODA), with an induced optimum cationic charge of 45.7 mV in the range of 152.1 nm, allowed maximum siRNA complexation, better stability, and higher transfection, with strong inhibition against the E2 and NS1 genes of CHIKV. The study concludes that cationic lipid-like ODA with ease of synthesis and characterization showed maximum complexation by structural condensation of siRNA owing to high transfection alone. Synergistic inhibition of CHIKV along with siRNA was demonstrated in both in vitro and in vivo models. Therefore, ODA-based cationic lipid nanoparticles can be explored as safe, potent, and efficient nonviral vectors overcoming siRNA in vivo complexities against chikungunya.  相似文献   
52.
In the present work, an experimental investigation of heat transfer enhancement parameters of the oscillating flow heat exchanger under different frequencies, tidal displacement, and heat fluxes is carried out. The effect of different parameters on experimental effective thermal conductivity and convective heat transfer coefficient in cooling region is studied using correlations given by different researchers. A correlation for experimental effective thermal conductivity in terms of S2√ω is derived based on experimental data. This correlation is useful for predicting the optimum value of S2√ω before onset of turbulence.  相似文献   
53.
For the ferrites Ni x Cd1–x Fe2O4 (x=0.3, 0.4,1) the lattice parameter, grain size, electrical resistivity, initial permeability, Curie temperature and squareness of the magnetization curve were measured. The results are discussed in terms of the model of the canted spin structure taking into account the domain structure of the polycrystalline ferrite.  相似文献   
54.
55.
Optical Networks-on-Chip (ONoC) is emerging technology for future optical interconnects used in all optical networks. The electrical interconnects face lot of problems due to their inability to support higher data rates used in the System-on-Chip (SoC) technologies. Integrated optical interconnects based on SoC avoid this bottleneck with their support to higher data rates. In this paper for the first time we have studied and analyzed ONoC at physical level for the system performance based on crosstalk, BER, throughput, system frequency, and other related parameters. The investigation of ONoC performance is carried out for the multistage microring optical crossconnect on SoC for coherent WDM signals. The analysis can be used in the design of ultra-high speed photonic routers for reliable data communication and processing. The results show the dependency of a coherent crosstalk on the system frequency of SoC and also illustrate the reduction in throughput with increase in number of WDM signals due to higher probability of packet transmission. Minimum 2 dB signal to noise ratio can be obtained when crosstalk is ?25 dB with 60 wavelengths for probability of packet transmission is 0.5.  相似文献   
56.
A rapid, simple, and accurate ion-pair RPLC method has been developed for simultaneous analysis of vitamin C and major B-complex vitamins. An RP C18 column thermostated at 30 degrees C was used with gradient elution of mobile phase comprising 10 mM potassium dihydrogen phosphate buffer (containing 3 mM sodium hexane-1-sulfonate, adjusted to pH 2.80 with o-phosphoric acid) and methanol at a flow rate of 1.0 mL/min to achieve the best possible separation and resolution of all vitamins in about 11.00 min. The detection was performed at 274 nm. The method has been implemented successfully for simultaneous determination of vitamins present in 12 multivitamin/multimineral pharmaceutical preparations, as well as in human urine. Typical validation characteristics were evaluated in accordance with International Conference on Harmonization guidelines. Good linearity over the investigated concentration levels was observed. Intraday repeatability was < or = 2.0%, and interday variation was < or = 2.6%, for all vitamins. The method can be used for assay of these vitamins over a wide concentration range with good precision and accuracy; hence, it would be appropriate for routine QC as well as in clinical analysis.  相似文献   
57.
A novel fluoranthene based fluorescent chemosensor for the detection of picric acid (PA) at the parts per billion (ppb) level was evaluated. Static fluorescence quenching was the dominant process by intercalative π-π interaction between fluoranthene (S(1)) and nitroaromatics.  相似文献   
58.
The inclusion complex of isatoic anhydride with β-cyclodextrin was formed as a result of intermolecular interaction between isatoic anhydride with β-CD. The inclusion complex was confirmed by IR spectroscopy, X-ray diffraction and DSC studies. From application of complex, herein we have described a simple and efficient protocol for synthesis of 2, 3-dihydroquinazoline-4(1H)-one derivatives by one pot condensation of isatoic anhydride, ammonium acetate or amine and aldehyde using β-CD as a supramolecular catalyst in aqueous media.  相似文献   
59.
A rapid method for selective cleavage of aryl methylethers can be achieved in the presence of a protic acid and a catalytic amount of phase-transfer catalyst (Aliquat-336). Aliquat-336 accelerates the rate of reaction and affords the corresponding phenols in excellent to good yields on a wide variety of substrates.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]  相似文献   
60.
Chromatographia - WCK 771 is a novel antibacterial drug recently launched in India for the treatment of acute bacterial skin and skin structure infections (ABSSSI). This report describes...  相似文献   
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