Near-infrared surface-enhanced Raman spectroscopy (SERS) is a powerful technique for analyzing the chemical composition within a single living cell at unprecedented resolution. However, current SERS ...methods employing uncontrollable colloidal metal particles or non-uniformly distributed metal particles on a substrate as SERS-active sites show relatively low reliability and reproducibility. Here, we report a highly-ordered SERS-active surface that is provided by a gold nano-dots array based on thermal evaporation of gold onto an ITO surface through a nanoporous alumina mask. This new combined technique showed a broader distribution of hot spots and a higher signal-to-noise ratio than current SERS techniques due to the highly reproducible and uniform geometrical structures over a large area. This SERS-active surface was applied as cell culture system to study living cells in situ within their culture environment without any external preparation processes. We applied this newly developed method to cell-based research to differentiate cell lines, cells at different cell cycle stages, and live/dead cells. The enhanced Raman signals achieved from each cell, which represent the changes in biochemical compositions, enabled differentiation of each state and the conditions of the cells. This SERS technique employing a tightly controlled nanostructure array can potentially be applied to single cell analysis, early cancer diagnosis and cell physiology research.
The analysis of 41Ca in concrete generated from the nuclear facilities decommissioning is critical for ensuring the safe management of radioactive waste. An analytical method for the determination of ...41Ca in concrete is described. 41Ca is a neutron-activated long radionuclide, and hence, for accurate analysis, it is necessary to completely extract Ca from the concrete sample where it exists as the predominant element. The decomposition methods employed were the acid leaching, microwave digestion, and alkali fusion. A comparison of the results indicated that the alkali fusion is the most suitable way for the separation of Ca from the concrete sample. Several processes of hydroxide and carbonate precipitation were employed to separate 41Ca from interferences. The method relies on the differences in the solubility of the generated products. The behavior of Ca and the interfering elements such as Fe, Ni, Co, Eu, Ba, and Sr is examined at each separation step. The purified 41Ca was measured by a liquid scintillation counter, and the quench curve and counting efficiency were determined by using a certified reference material of known 41Ca activity. The recoveries in this study ranged from 56 to 68%, and the minimum detectable activity was 50 mBq g−1 with 0.5 g of concrete sample.
Organic light‐emitting diodes (OLEDs) and polymer light‐emitting diodes (PLEDs) are considered promising devices in that they are not limited to conventional display devices and can provide versatile ...functions in photomedicine. Many attempts to replace rigid photomedicine devices with wearable light‐emitting devices are in progress, and OLEDs have shown feasibility with respect to device conformality and photo‐medical efficiency. This paper presents a newly designed flexible optoelectronic device utilizing a wavelength‐designable PLED as an option for realizing disposable photomedicine devices. An optical design based on a multilayer electrode and an additional injection unit is proposed; it allows control of the device peak wavelength without any deterioration of charge injection. Furthermore, a sandwich structure utilizing transferable thin‐film encapsulation enables the PLED to achieve mechanical flexibility, low device heat generation, and sufficient operational lifetime (>8 h). When fibroblasts are irradiated by the wavelength‐designable PLED with a 630 nm peak, cell proliferation and production of type‐I procollagen increase by 25% and 36%, respectively. The change of matrix metalloproteinase‐1 is also evaluated, and it is found to decrease by 23%. Based on these results, the wavelength‐designable PLED induces distinct changes of biological factors.
Flexible and wavelength‐designable polymer light‐emitting diodes are demonstrated and the in vitro test for human fibroblasts is carried out to prove their feasibility to skin rejuvenation. When fibroblast cells are irradiated by the suggested devices, the fibroblast proliferation and production of type‐I procollagen increase by 25% and 36%, respectively, and the matrix metalloproteinase‐1 decrease by 23%.
Nano-sized drug delivery system has been widely studied as a potential technique to promote tumor-specific delivery of anticancer drugs due to its passive targeting property, but resulting in very ...restricted improvements in its systemic administration so far. There is a requirement for a different approach that dramatically increases the targeting efficiency of therapeutic agents at targeted tumor tissues. To improve the tumor-specific accumulation of anticancer drugs and minimize their undesirable toxicity to normal tissues, a tumor-implantable micro-syringe chip (MSC) with a drug reservoir is fabricated. As a clinically established delivery system, six liposome nanoparticles (LNPs) with different compositions and surface chemistry are prepared and their physicochemical properties and cellular uptake are examined in vitro. Subsequently, MSC-guided intratumoral administration is studied to identify the most appropriate for the higher tumor targeting efficacy with a uniform intratumoral distribution. For efficient cancer treatment, pro-apoptotic anticancer prodrugs (SMAC-P-FRRG-DOX) are encapsulated to the optimal LNPs (SMAC-P-FRRG-DOX encapsulating LNPs; ApoLNPs), then the ApoLNPs are loaded into the 1 muL-volume drug reservoir of MSC to be delivered intratumorally for 9 h. The tumor accumulation and therapeutic effect of ApoLNPs administered via MSC guidance are evaluated and compared to those of intravenous and intratumoral administration of ApoLNP in 4T1 tumor-bearing mice. MSC is precisely fabricated to have a 0.5 x 4.5 mm needle and 1 muL-volume drug reservoir to achieve the uniform intratumoral distribution of LNPs in targeted tumor tissues. Six liposome nanoparticles with different compositions of 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine (PC), 1,2-dioleoyl-sn-glycero-3-phospho-L-serine (PS), 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy (polyethylene glycol).sub.2000 (PEG.sub.2000-DSPE) are prepared with average sizes of 100-120 nm and loaded into the 1 muL-volume drug reservoir in MSC. Importantly negatively charged 10 mol% of PS-containing LNPs are very slowly infused into the tumor tissue through the micro-syringe of the MSC over 6 h. The intratumoral targeting efficiency of MSC guidance is 93.5%, effectively assisting the homogeneous diffusion of LNPs throughout the tumor tissue at 3.8- and 2.7-fold higher concentrations compared to the intravenous and intratumoral administrations of LNPs, respectively. Among the six LNP candidates 10 mol% of PS-containing LNPs are finally selected for preparing pro-apoptotic SMAC-P-FRRG-DOX anticancer prodrug-encapsulated LNPs (ApoLNPs) due to their moderate endocytosis rate high tumor accumulation and homogenous intratumoral distribution. The ApoLNPs show a high therapeutic effect specifically to cathepsin B-overexpressing cancer cells with 6.6 muM of IC.sub.50 value while its IC.sub.50 against normal cells is 230.7 muM. The MSC-guided administration of ApoLNPs efficiently inhibits tumor growth wherein the size of the tumor is 4.7- and 2.2-fold smaller than those treated with saline and intratumoral ApoLNP without MSC, respectively. Moreover, the ApoLNPs remarkably reduce the inhibitor of apoptosis proteins (IAPs) level in tumor tissues confirming their efficacy even in cancers with high drug resistance. The MSC-guided administration of LNPs greatly enhances the therapeutic efficiency of anticancer drugs via the slow diffusion mechanism through micro-syringe to tumor tissues for 6 h, whereas they bypass most hurdles of systemic delivery including hepatic metabolism, rapid renal clearance, and interaction with blood components or other normal tissues, resulting in the minimum toxicity to normal tissues. The negatively charged ApoLNPs with cancer cell-specific pro-apoptotic prodrug (SMAC-P-FRRG-DOX) show the highest tumor-targeting efficacy when they are treated with the MSC guidance, compared to their intravenous or intratumoral administration in 4T1 tumor-bearing mice. The MSC-guided administration of anticancer drug-encapsulated LNPs is expected to be a potent platform system that facilitates overcoming the limitations of systemic drug administration with low delivery efficiency and serious side effects.
We address object tracking problem as a multitask feature learning process based on low-rank representation of features with joint sparsity. We first select features with low-rank representation ...within a number of initial frames to obtain subspace basis. Next, the features represented by the low-rank and sparse property are learned using a modified joint sparsity-based multitask feature learning framework. Both the features and sparse errors are then optimally updated using a novel incremental alternating direction method. The low-rank minimization problem for learning multitask features can be achieved by a few sequences of efficient closed form update process. Since the proposed method attempts to perform the feature learning problem in both multitask and low-rank manner, it can not only reduce the dimension but also improve the tracking performance without drift. Experimental results demonstrate that the proposed method outperforms existing state-of-the-art tracking methods for tracking objects in challenging image sequences.
This study investigated an analytical method for detecting
90
Sr in soil samples for the routine monitoring of environmental radioactivity. Mineral acid leaching and fusion methods were first used to ...digest the soil sample, and the analytical results were compared. DGA resin was employed to separate
90
Y, being a daughter of
90
Sr. Then,
90
Y was analyzed by liquid scintillation counter (LSC). These analytical results were compared with those obtained using Sr resin, which is a well-known, simple and reliable separation method. With the DGA resin approach a minimum detectable activity of ~0.28 Bq kg
−1
was detected in a 50 g sample, with 180 min of counting time, 70% recovery and ~97% counting efficiency using a LSC.
A direct-patternable ZnO thin film was prepared by photochemical solution deposition and the electrical properties were improved by the incorporation of graphene. The transmittance of ...graphene-incorporated ZnO thin films was similar to that of ZnO thin film due to the incorporation of graphene, which slightly decreased the crystallinity of the ZnO thin films. In addition, the resistivity was improved due to the enhanced mobility due to the π-bond nature of the graphene surface. Graphene-incorporated ZnO thin film was direct-patterned through photochemical solution deposition without a photoresist or conventional dry etching process. These results suggest that a micro-patterned system can be simply fabricated at low cost, and the electrical properties of ZnO thin films can be improved by incorporating graphene.
► Transparent ZnO thin film ► π-bond on surface of graphene has higher electrical mobility. ► Graphene incorporation was not affected to crystallinity and transmittance. ► Electrical conductivity was enhanced by graphene incorporation.
The design, management, and operation of network infrastructure have evolved during the last few years, leveraging on innovative technologies and architectures. With such a huge trend, due to the ...flexibility and significant economic potential of these technologies, software-defined networking (SDN) and network functions virtualization (NFV) are emerging as the most indispensable key catalysers. SDN/NFV enhancing the infrastructure agility, thus network operators and service providers are able to program their own network functions (e.g., gateways, routers, load balancers) on vendor-independent hardware substrate. One of the most important considerations in NFV deployment is how to allocate the virtual resources that are needed to provide flexible virtual network services in an NFV-based network infrastructure. Thus, the most important prerequisite for NFV deployment is achieved fast, scalable and dynamic composition and allocation of networks functions (NFs) to implement network services (NSs). We have proposed a revised RA algorithm that integrates embedding and scheduling of virtual network functions (VNFs) simultaneously. In this paper, performance evaluation of the revised RA algorithm is performed and the proposed algorithm is applied more effectively in NFV environment where the demand for resources is flexible and concentrated.
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•We synthesized Prussian blue incorporated polyacrylonitrile nanofiber (PB/PAN).•PB nanoparticles can be incorporated successfully into the PAN matrix.•With simple filtering for the ...137Cs removal, PB/PAN showed high removal efficiency.•PB/PAN showed high 137Cs removal efficiency even in the actual seawater medium.•PB/PAN can be practically applied for the Cs removal from radioactive wastewater.
After the Fukushima Daiichi Nuclear Power Plant disaster in Japan in 2011, the demand drastically increased for efficient technology for the removal of radioactive cesium. Prussian blue (PB) nanoparticles have shown excellent adsorption ability toward Cs. In this study, we synthesized PB nanoparticles incorporated polyacrylonitrile nanofiber (PB/PAN). PB/PAN has the porous structure of nanofibers, with diameters of several hundred nanometers. PB nanoparticles can be incorporated successfully into the PAN matrix without any change to their intrinsic crystallinity and structure. The mesoporous structure of PB/PAN and the incorporation of PB nanoparticles led to an increase in the Brunauer–Emmett–Teller surface area and pore volume. In addition, PB/PAN exhibited excellent wettability with water. With simple filtering for the removal of radioactive cesium, PB/PAN showed high removal efficiency (87 ± 3%) within 10 s for 10 mL of 137Cs solution (1000 Bq L−1). In addition, the 137Cs removal by PB/PAN showed high removal efficiency (70 ± 2%, after 1 h), even in the actual seawater medium (1000 Bq L−1 of 137Cs). Therefore, PB-incorporated PAN nanofibers can be considered useful in the practical application of Cs removal from radioactive wastewater.
•Human senses and characteristics are applied to the evacuation simulation.•Occupants can change routes depending on the situation during the simulation.•Bottleneck Algorithm is reflecting ...personality of each occupant.•The Active Route Choice Model can improve the accuracy of evacuation simulation.
Modern buildings have become larger in scale and function, and the complexity has also increased considerably. For these reasons, there are more difficulties in evacuation and rescue when an emergency occurs, so effective evacuation methods and risk should be predicted and applied to building design, safety training, and education. We have developed an active route choice model based on human body organs and characteristics that detects risks and route conditions, communicates with neighboring occupants, determines the bottleneck point, and selects evacuation routes according to each occupant's personal characteristics. In this study, we introduce the implementation process and characteristics of the active route choice model, and by applying the model to the occupants, we compared the evacuation times according to the route condition, number of occupants, and corridor width in a virtual environment. We believe that realistic and valid results can be obtained by applying the active route choice model in crowd evacuation simulation.
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