Highly efficient gene silencing and bioimaging based on fluorescent carbon dots <Emphasis Type="Italic">in vitro</Emphasis> and <Emphasis Type="Italic">in vivo</Emphasis>

Small interfering RNA (siRNA) is an attractive therapeutic candidate for sequencespecific gene silencing to treat incurable diseases using small molecule drugs.However,its efficient intracellular delivery has remained a challenge.Here,we have developed a highly biocompatible fluorescent carbon dot (CD),and demonstrate a functional siRNA delivery system that induces efficient gene knockdown in vitro and in vivo.We found that CD nanoparticles (NPs) enhance the cellular uptake of siRNA,via endocytosis in tumor cells,with low cytotoxicity and unexpected immune responses.Real-time study of fluorescence imaging in live cells shows that CD NPs favorably localize in cytoplasm and successfully release siRNA within 12 h.Moreover,we demonstrate that CD NP-mediated siRNA delivery significantly silences green fluorescence protein (GFP) expression and inhibits tumor growth in a breast cancer cell xenograft mouse model of tumor-specific therapy.We have developed a multi functional siRNA delivery vehicle enabling simultaneous bioimaging and efficient downregulation of gene expression,that shows excellent potential for gene therapy.     

Phase behaviour of poly(benzophenoneimide)s having n-alkyloxymethyl side chains

A series of poly(benzophenoneimide)s (C_m-BP-PIs) having n-alkyloxymethyl side chains (−CH₂O-n-CmH_2m+1, m = 4, 6, 8) have been examined by X-ray diffraction, differential scanning calorimetry (DSC) and polarizing optical microscopy. The samples showed basically two phase transitions and both transition temperatures decreased with increasing side chain length. The first transitions were ascribed to glass transitions and the second ones were assigned to liquid crystal-to-isotropic transitions. Eicosane (n-C₂₀H₄₂) which is chemically very similar to the side chain was miscible with the side chains of C₈-BP-PI, which induced depression of the glass transition temperature. Received: 17 February 1997/Revised: 1 April 1997/Accepted: 4 April 1997     

An experimental study on the environmental performance of the automated blind in summer

Blinds are used widely in numerous buildings to conserve energy and provide for occupants' comfort in the perimeter zone. However, manual or motorized blinds are limited in their ability to reduce energy consumption and to provide comfort because occupants themselves must operate blinds to block direct solar radiation. Thus, the use of automated blinds would more fully exploit the full benefits of blinds.     

Master equation and Fokker-Planck methods for void nucleation and growth in irradiation swelling

A complete theory of void swelling in irradiated metals requires the treatment of defect cluster nucleation events, as well as subsequent growth of stable clusters. One difficulty is that small-voids evolve rapidly and reversibly, whereas the secular evolution of the overall system is extremely slow. Thus, rate theory models for the void size distribution entail a set of stiff, coupled equations. A combined Master equation and Fokker-Planck numerical approach is introduced to address this problem and permit large time-steps at late times. Calculations are stable in practice, easily converged, and computationally efficient to large doses over a wide range in temperatures. The results are encouraging compared to experiment and earlier, related calculations.     

Analysis of Barrier Defects in Low-<Emphasis Type="Italic">k</Emphasis>/Cu Interconnects Based on Electrochemical Response and Simulation Cell

The electrochemical mechanism behind voltammograms produced by defective barriers in low-k/Cu interconnect structures is investigated using simulation cells which mimic various barrier conditions. The findings reveal that the Cu reaction peak current used as an indicator for barrier defects represents oxidation of Cu at the anodic electrode. When both electrodes have similar defect (Cu) fraction, the voltammogram is symmetric, but when the electrodes have different Cu fraction, the voltammogram is asymmetric and changes during repeated cycling until a stable form is reached.     

Fully integrated unequal Wilkinson power divider with EBG CPW

In this paper, a CPW with electromagnetic bandgap (EBG CPW) is newly proposed for designing a transmission line with high impedance. After designing, fabricating, and evaluating the characteristic impedance of the proposed EBG CPW transmission line, it will be applied to an integrated unequal Wilkinson power divider. In the EM simulation, the EBG-CPW transmission line with 10 /spl mu/m in line width has the same characteristic impedance as a CPW with a line width of 2.5 /spl mu/m. The insertion and return losses of the fabricated power divider with a power ratio of 1 to 3 are less than -0.7 dB and -15 dB, respectively. It also has excellent isolation characteristics with more than -20 dB. The experimental results are good agreement with the simulation.     

Insecticidal activities of aromatic plant extracts and essential oils against Sitophilus oryzae and Callosobruchus chinensis

Methanol extracts from 30 aromatic medicinal plant species and five essential oils were tested for their insecticidal activities against adults of Sitophilus oryzae (L.) and Callosobruchus chinensis (L.), using direct contact application and fumigation methods. Responses varied with plant material, insect species, and exposure time. In a test with a filter paper diffusion method at 3.5 mg/cm², potent insecticidal activity against both species was produced by an extract from Cinnamomum cassia bark, cinnamon (C. cassia) oil, horseradish (Cocholeria aroracia) oil, and mustard (Brassica juncea) oil within 1 day after treatment. Over 90% mortality at 3 or 4 days after treatment was achieved using extracts of Acorus calamus var. angustatus rhizome, Acorus gramineus rhizome, Illicium verum fruit, and Foeniculum vulgare fruit. An extract from Cinnamomum sieboldii root bark gave 100% mortality at 2 days after treatment. At 0.7 mg/cm², extracts from C. cassia, C. sieboldii, and F. vulgare as well as cinnamon oil, horseradish oil and mustard oil were highly effective against both species. In a fumigation test with S. oryzae adults, the oils described were much more effective in closed containers than in open ones, indicating that the insecticidal activity of the oils was attributable to fumigant action. The plant extracts and essential oils described could be useful for managing field populations of S. oryzae and C. chinensis.     

A Fast H.264 Intra Frame Encoder with Serialized Execution of 4 × 4 and 16 × 16 Predictions and Early Termination

This paper presents a fast H.264 intra frame encoder that processes a single macroblock of 1920 × 1080 size video in 334 cycles on average which is 20% faster than the previous best design. The speed-up is mainly achieved by early termination of either 4 × 4 intra prediction or 16 × 16 intra prediction. The executions of intra 4 × 4 and 16 × 16 predictions are serialized and the second prediction is terminated early by using the cost of the first prediction as the stop criterion. A simple and efficient algorithm by making use of spatial locality is proposed to select the mode that is processed first. To avoid the bubble cycles caused by this serialized execution of 4 × 4 and 16 × 16 predictions, the modified processing order presented in (Jung et al. 2008) is employed for intra 4 × 4 prediction in order to schedule dependent 4 × 4 blocks apart from each other. To further reduce the execution time of 4 × 4 prediction, neighboring pixels with the same value are grouped, and only one prediction mode in the group is evaluated. Experimental results show that the PSNR drop is 0.0619 dB and the bitrate increase is 0.842% when compared with the JM reference software. The additional hardware cost to support the proposed methods is less than eight thousand gates which are very small when compared with the hardware size of a whole intra frame encoder.     

Microstructural Evolution During the Infiltration Treatment of Titanium Carbide-Iron Composite

The microstructural evolution of grain-matrix interfaces in TiC-Fe cermet has been observed and explained in terms of equilibration reaction and interfacial energy minimization. The coherency strain energy is assumed to be the driving force for enhanced dissolution of certain specific planes, which results in a very irregular grain shape. The equilibrium shape appears after heat treatment for a long period.