Locally adaptive bilateral clustering for universal image denoising

This paper presents a novel and efficient locally adaptive denoising method based on clustering of pixels into regions of similar geometric and radiometric structures. Clustering is performed by adaptively segmenting pixels in the local kernel based on their augmented variational series. Then, noise pixels are restored by selectively considering the radiometric and spatial properties of every pixel in the formed clusters. The proposed method is exceedingly robust in conveying reliable local structural information even in the presence of noise. As a result, the proposed method substantially outperforms other state-of-the-art methods in terms of image restoration and computational cost. We support our claims with ample simulated and real data experiments. The relatively fast runtime from extensive simulations also suggests that the proposed method is suitable for a variety of image-based products ?? either embedded in image capturing devices or applied as image enhancement software.     

Multi-quasiparticle excitations in ~(145)Tb

Nuclei with N and Z near magic number can be well described by the nuclear shell model. The 145Tb nucleus has a valence proton and a pair of neutron holes with respect to the doubly closed 146Gd nucleus. Therefore, it is expected that the excitations in 145Tb be dominated by single-particle configurations. A detailed measurement of the excitation scheme in 145Tb would give us an opportunity to examine the behavior of multi-particle excitations involving high angular momentum orbits and provi…     

Analysis of toxic elements by MPGA

In order to improve the sensitivity for the quantification of trace elements, we propose the combination of prompt gamma-ray analysis (PGA) and a multiple gamma-ray detection method. A new Ge detector system for multiple prompt gamma-ray analysis (MPGA) was constructed at the neutron guide-hall of the JRR-3M reactor of the Japan Atomic Energy Agency (JAEA). The first demonstration of this system was given with a plastic sample containing traces of cadmium. The quantification limit of cadmium in a plastic sample was found to be about 0.1 ppm.     

Chemical structure of composites derived from poly(silicic acid) and 2‐hydroxyethylmethacrylate

Organic–inorganic hybrids from 2‐hydroxyethylmethacrylate (HEMA) and poly(silicic acid)s were prepared and characterized. The molecular architecture of the inorganic phase was studied with ²⁹Si NMR spectroscopy, and the effect of acid concentration and reaction time on the properties of poly(silicic acid) were elucidated. Interactions between phases were studied with NMR spectroscopy and gel permeation chromatography, and the coexistence and connectivity of the two phases were investigated. Contrary to previous assumptions, evidence was found that indicated that the organic and inorganic phases of this class of sol–gel materials were not covalently linked. The curing process was studied by infrared spectroscopy, by which the disappearance of terminal double bonds of HEMA monomer were monitored. Thermogravimetric analysis profiles showed that the inorganic phase content was about 10 wt %, and it was varied slightly by changes in the molar ratio of the components. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1342–1352, 2001     

Systemically Injectable Enzyme‐Loaded Polyion Complex Vesicles as In Vivo Nanoreactors Functioning in Tumors

The design and construction of nanoreactors are important for biomedical applications of enzymes, but lipid‐ and polymeric‐vesicle‐based nanoreactors have some practical limitations. We have succeeded in preparing enzyme‐loaded polyion complex vesicles (PICsomes) through a facile protein‐loading method. The preservation of enzyme activity was confirmed even after cross‐linking of the PICsomes. The cross‐linked β‐galactosidase‐loaded PICsomes (β‐gal@PICsomes) selectively accumulated in the tumor tissue of mice. Moreover, a model prodrug, HMDER‐βGal, was successfully converted into a highly fluorescent product, HMDER, at the tumor site, even 4 days after administration of the β‐gal@PICsomes. Intravital confocal microscopy showed continuous production of HMDER and its distribution throughout the tumor tissues. Thus, enzyme‐loaded PICsomes are useful for prodrug activation at the tumor site and could be a versatile platform for enzyme delivery in enzyme prodrug therapy.     

Anodic Stripping Voltammetry of Silver Nanoparticles: Aggregation Leads to Incomplete Stripping

The influence of nanoparticle aggregation on anodic stripping voltammetry is reported. Dopamine-capped silver nanoparticles were chosen as a model system, and melamine was used to induce aggregation in the nanoparticles. Through the anodic stripping of the silver nanoparticles that were aggregated to different extents, it was found that the peak area of the oxidative signal corresponding to the stripping of silver to silver(I) ions decreases with increasing aggregation. Aggregation causes incomplete stripping of the silver nanoparticles. Two possible mechanisms of ‘partial oxidation’ and ‘inactivation’ of the nanoparticles are proposed to account for this finding. Aggregation effects must be considered when anodic stripping voltammetry is used for nanoparticle detection and quantification. Hence, drop casting, which is known to lead to aggregation, is not encouraged for preparing electrodes for analytical purposes.     

Heterogeneous and Homogeneous Aptamer‐Based Electrochemical Sensors for Thrombin

Nanomolar concentrations of thrombin were electrochemically monitored using heterogeneous switch‐on and homogeneous switch‐off approaches that incorporated ferrocenyl aptamers. For the first time, the heterogeneous approach was coupled to a glucose/glucose oxidase (GOx) amplification‐regeneration system which increased its sensitivity by 2 folds with detection limits of 4.3 nM and 2.5 nM in the absence and presence of glucose/GOx, respectively. We also present a new homogeneous system involving the ferrocenyl aptamer binding thrombin in solution causing a significant decrease in its diffusion coefficient. Thus the ferrocene anodic current decreased at an unmodified gold electrode with detection limit of 3.9 nM and 12 times larger linear range than the heterogeneous method.