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Melanin-like nanoparticles were synthesized with size control through neutralization of dopamine hydrochloride with NaOH, followed by spontaneous air oxidation of dopamine. Although the particle characteristic of natural melanins was understood to be significantly affected by the biological and structural environment, melanin-lke nanoparticles can be realized through the chemical reactions only. Melanin-like nanoparticles that are

We have developed a simple, efficient, and highly reproducible method to fabricate the large-area biomimetic superhydrophobic polymer surfaces having hierarchical structures of micrometer-sized irregular steps and nanometer-sized fibrils. Commercial Al plates (99.0%) were etched using Beck's dislocation etchant (mixture of HCl and HF) for different time periods in order to alter the structure of the etched Al surfaces from micrometer-sized to highly rough nanometer-sized irregular steps. These hierarchical structures could be easily replicated onto the surface of various thermoplastic polymer plates from the etched Al templates by applying heat and pressure; many polymer replicas without any significant deviations from each other could be duplicated from the same etched Al master templates. All of thermoplastic polymer replicas having hierarchical structures exhibited superhydrophobic properties with water contact angles of larger than 150 degrees. Especially, the surfaces of the high-density polyethylene (HDPE) replicas having nanometer-sized curled strands exhibited superhydrophobicity with a static water contact angle of approximately 160 degrees and a sliding angle of less than 2 degrees. These superhydrophobic HDPE replicas having nanometer-sized curled strands showed excellent stability after being exposed to various organic solvents and aqueous solutions of various pH.

Internal nanostructures in nanorods of polystyrene-poly(4-vinyl pyridine) (PS-PVP) diblock copolymers fabricated from pores having regular or irregular contours in AAO templates were investigated by cross-sectional transmission electron microscopy. When nanorods of PS-PVP copolymers were produced from pores with regular contours, a typical morphology of concentric cylinders was observed due to the strong affinity of the PVP block to the surface of the AAO pores. In the case of PS-PVP nanorods obtained from pores with irregular contours, a concentric cylindrical morphology was not induced. Instead, a nanostructure of lamellae mostly parallel to the axis of the nanorods was observed with a similar period of lamellae to the bulk lamellar period. In addition, nanorods having a functional coaxial nanostructure were fabricated by synthesizing Au nanoparticles in concentric cylinders of the nanorods to demonstrate the utilization of self-assembled internal nanostructures in nanorods.

The durability of the suspension system is a critical component in the development of a vehicle because it is consistently and directly exposed to dynamic loads while the vehicle is in motion. In most cases, attempts are made to improve the durability of a vehicle suspension system by changing the shapes of its parts and components. However, the authors propose to improve the overall durability performance of a vehicle suspension system by modifying the compliance of the elastomeric bushings, which pivotally connect the lower control arm to the vehicle frame. It is relatively easy and cost effective to change the compliance of the bushing components because they are made of rubber or elastomeric materials. The following procedure was used for the present analysis. Firstly, dynamic loads were obtained based on a multi-body dynamic analysis while the vehicle was driven on a virtual proving ground test. Secondly, the stress distribution of the vehicle suspension system was calculated using finite element analysis to obtain an optimal combination of the elastomeric bushing compliance and provide the maximum improvement to the stress distribution on the basis of a robust design approach. Finally, the durability performance of each component in the vehicle suspension system was evaluated using quasi-static durability analyses. The fatigue life of the optimal model was improved by 36—39 per cent when the knuckle and lower control arm passed over bumps, and by 30—41 per cent when they passed over potholes. The proposed optimal design process to improve the elastomeric bushing compliance made it easy to evaluate and improve the durability performance of the vehicle suspension system in the initial stages of the vehicle development process.

Well-defined hierarchical structures, 3-dimensional upright structures containing aligned nanoembosses or nanoposts within micron-sized patterned areas, were realized on a polymer surface by utilizing patterned anodized aluminum oxide (AAO) and electrochemical reactions followed by a heat- and pressure-driven polymer imprinting technique. Sputtered Al on AAO could work excellently as a mask for the selective etching of AAO and successive anodization processes and many interesting hierarchical structures could be generated on an Al surface, from which hierarchical structures could be reproducibly duplicated onto polymer surfaces.

Three cryptic species, Aphis gossypii, Aphis glycines, and Aphis rhamnicola sp. nov., are recognized as sharing buckthorn plant, Rhamnus spp. as primary hosts. These aphid species have morphological similarities; however, there are significant genetic differences between the three cryptic species. Based on the high level of genetic divergence and the different secondary host association, we described a new species, Aphis rhamnicola sp. nov., for apterous and alate vivipara, fundatrix, ovipara, and gynopara, including diagnostic key for the host sharing species in the genus Aphis.

Current mobile devices usually provide streaming media for users. While the online multimedia processing requires intensive computation, the characteristics of mobility and portability place a severe energy constraint on the system. In this paper, we aim to develop a systematic methodology for dealing with low-energy computation for the MPEG-4 video decoding. Our approach is based on a new fine-controllable, quality-adaptive technique to reduce data volumes, which results in energy saving. To do so, we introduce a requantization step to the video decoding process. The proposed requantization ensures that the energy consumption reduces at higher rate than the video quality degrades, and that the videos remain intelligible to a human viewer. The experimental results show that the energy consumption is reduced by up to 42% with 13% quality degradation, thereby confirming the efficacy of the quality-adaptive requantization.

Zn diffusion into InP was carried out ex-situ using a spin-on dopant as a diffusion source. The characteristics of Zn-doped InP are analyzed using low-temperature photoluminescence (PL), differential Hall measurement, and secondary ion mass spectrometry (SIMS). Dopant activation of Zn is close to 100% using this method. Band-to-acceptor (B-A) transition peak is dominant in PL, which is a characteristic usually found in in-situ doping. This evidence along with an activation energy of 0.5 eV show that the diffusion is substitutional rather than interstitial.

In this paper, we present evidence that ginsenoside-Rs4 (G-Rs4; an acetylated analogue of ginsenoside-Rg5), a new ginseng saponin isolated from Panax ginseng C. A. Meyer, elevates protein levels of p53 and p21WAF1, which are associated with the induction of apoptosis in SK-HEP-1 cells. Flow cytometric analyses showed that G-Rs4 initially arrested the cell cycle at the G1/S boundary, but consequently induced apoptosis as evidenced by generating an apoptotic peak. The induction of apoptosis was confirmed by the results of DNA fragmentation assays and alterations in cell morphology after treatment of the cells with G-Rs4. Immunoblot assays showed that G-Rs4 significantly elevated protein levels of p53 and p21WAF1, concurrently with the downregulation of both cyclins E- and A-dependent kinase activities and induction of apoptosis. We suggest that G-Rs4 induces apoptosis, the effect of which is closely related to the downregulation of both cyclins E- and A-dependent kinase activity as a consequence of selectively elevating protein levels of p53 and p21WAF1 in SK-HEP-1 cells.

Magnetic nanoparticles (MNPs) have proven themselves to be useful in biomedical research; however, previous reports were insufficient to address the potential dangers of nanoparticles. Here, we investigated gene expression and metabolic changes based on the microarray and gas chromatography-mass spectrometry with human embryo kidney 293 cells treated with MNPs@SiO(2)(RITC), a silica-coated MNP containing Rhodamine B isothiocyanate (RITC). In addition, measurement of reactive oxygen species (ROS) and ATP analysis were performed to evaluate the effect of MNPs@SiO(2)(RITC) on mitochondrial function. Compared to the nontreated control, glutamic acid was increased by more than 2.0-fold, and expression of genes related to the glutamic acid metabolic pathway was also disturbed in 1.0 μg/μL of MNPs@SiO(2)(RITC)-treated cells. Furthermore, increases in ROS concentration and mitochondrial damage were observed in this MNPs@SiO(2)(RITC) concentration. The organic acids related to the Krebs cycle were also disturbed, and the capacity of ATP synthesis was decreased in cell treated with an overdose of MNPs@SiO(2)(RITC). Collectively, these results suggest that overdose (1.0 μg/μL) of MNPs caused transcriptomic and metabolic disturbance. In addition, we suggest that a combination of gene expression and metabolic profiles will provide more detailed and sensitive toxicological evaluation for nanoparticles.

Using a mixed-dye injection technique, we found a novel kind of muscle fiber with a lumen, established its precise location in the subcutaneous muscle layer along the acupuncture muscle of the bladder line, and determined its detailed ultrastructure. The channels with flowing liquid were a novel kind of muscle fibers with lumens and they were located in the subcutaneous muscle layer of rat. Their detection was realized by using chrome-hematoxylin and a mixture of fluorescent nanoparticles and commercial Pelikan ink. These acupuncture muscle channels were hidden among the neighboring skin skeletal muscle fibers and were barely distinguishable from them with light microscopes. Only with a transmission electron microscope were their characteristic features shown to be different from normal skin skeletal muscle. These features included undifferentiated muscle fibers that resembled immature myofibrils without Z-lines and reassembled telophase nuclei.

Plant reacts to pathogen attack by activating multiple defense mechanisms as a result from the interaction of resistance gene in the plant and a corresponding avirulence gene in the pathogen. Interaction of the resistance and avirulence genes would stimulate a signalling cascade leading to the activation of defense mechanisms; hypersensitive response (HR), production of reactive oxygen species, cell wall fortification, accumulation of salicylic acid and phytoalexin, and induction of PR genes (reviewed in Bent, 1996; Hammond-Kosack and Jones, 1996).

Polymer nanotubes (PNTs) were fabricated by a simple spin casting of the polymer solution into nanochannels of anodic aluminum oxide (AAO) membranes. The thickness of the polymer nanotubes could be reproducibly controlled by changing the concentration of the polymer solutions. Furthermore, multiple spin casting of different polymer solutions could produce multi-layer PNTs (MPNTs), whose formation was confirmed by a selective staining technique in transmission electron microscope (TEM) experiments. Luminescent molecules such as blue-emitting Ir(III) complex and orange-emitting rhodamine B derivative could be uniformly incorporated into each polymer layer simply by mixing them into each polymer solution. These dye-incorporated MPNTs could be easily fabricated by the same spin casting method. Their optical properties were determined by UV-Vis spectroscopy, photoluminescence, and fluorescence microscopy. The morphology of the nanotubes was characterized using a field emission-scanning electron microscope (FE-SEM) and TEM. These results showed that the MPNTs could be reproducibly fabricated throughout the length of the nanochannels of the AAO templates.

Objective: To determine the feasibility of labeling human mesenchymal stem cells (hMSCs) with bifunctional nanoparticles and assessing their potential as imaging probes in the monitoring of hMSC transplantation. Materials and Methods: The T1 and T2 relaxivities of the nanoparticles (MNP@SiO2[RITC]-PEG) were measured at 1.5T and 3T magnetic resonance scanner. Using hMSCs and the nanoparticles, labeling efficiency, toxicity, and proliferation were assessed. Confocal laser scanning microscopy and transmission electron microscopy were used to specify the intracellular localization of the endocytosed iron nanoparticles. We also observed in vitro and in vivo visualization of the labeled hMSCs with a 3T MR scanner and optical imaging. Results: MNP@SiO 2 (RITC)-PEG showed both superparamagnetic and fluorescent properties. The r 1 and r 2 relaxivity values of the MNP@SiO2(RITC)-PEG were 0.33 and 398 mM -1 s -1 at 1.5T, respectively, and 0.29 and 453 mM -1 s -1 at 3T, respectively. The effective internalization of MNP@SiO2(RITC)-PEG into hMSCs was observed by confocal laser scanning fluorescence microscopy. The transmission electron microscopy images showed that MNP@SiO2(RITC)-PEG was internalized into the cells and mainly resided in the cytoplasm. The viability and proliferation of MNP@SiO2(RITC)-PEG-labeled hMSCs were not significantly different from the control cells. MNP@SiO2(RITC)-PEG-labeled hMSCs were observed in vitro and in vivo with optical and MR imaging. Conclusion: MNP@SiO2(RITC)-PEG can be a useful contrast agent for stem cell imaging, which is suitable for a bimodal detection by MRI and optical imaging.

A porous anodic aluminum oxide (AAO) template was fabricated selectively on a patterned substrate from a sputter-deposited Al film. The pattern size was varied from 2 to 500 μm with a depth of 1.5 μm. The overall surface undulation of Al resulting from the underlying patterns was planarized by chemical mechanical polishing. During the anodization of the confined Al, the anodization rate was significantly retarded at the vertical sidewall of the pattern. This suggests that the stress should be carefully controlled for the successful integration of a porous AAO structure on a patterned substrate.

Large area SERS (surface-enhanced Raman scattering)-active films with closely packed nanoembossed Ag arrays were reproducibly fabricated by the replication method of polymer surfaces with nano-size grooved Al masters. Three different sizes (60, 105 and 420 nm) of nanoembossed polymer surface were produced from three different replication masters obtained by controlled anodization conditions of Al, which could be further coated with silver in various thicknesses by an ion sputtering technique. Nanoembossed Ag films with an emboss size of 420 nm, uniformly formed over all the areas of 1 × 1 cm2, exhibit very even SERS activity and the enhancement factor estimated using benzenethiol as a prototype adsorbate reaches as large as 6.6 × 105. Many replicas of polyethylene and polystyrene could be produced from one replication master by this simple replication method with high reproducibility. Almost the same SERS intensities were observed in ten different spots of each replica and twenty different replicas from one replication master.