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In order to evaluate the heating process of the target and the optimal structure of cavity in a furnace for dielectric heating, such as a microwave oven, the coupled analysis method composed of electromagnetic wave and heat conduction is a powerful tool for practical design. In this paper, we proposed the electromagnetic wave analysis method with a nonconforming mesh connection to take account of the rotational motion of the specific objects in a cavity resonator. The features such as a numerical error and convergence characteristics of the ICCOCG method were investigated, and the proposed method was applied to the dielectric heating analysis of the cavity resonator with rotation of stirrer fans. Index Terms--Finite-element method, high-frequency domain, nonconforming mesh connection, rotational motion, stirrer fan.

A compact soft x-ray source using Thomson scattering was developed aiming at biological studies such as those using an x-ray microscope. Upon collision of the electron beam with the amplified laser beam 300 eV soft x-rays were generated by Thomson backscattering.

The distance dependence of the diffusion constant in hyaluronan (HA) aqueous solution, measured by pulsed field gradient NMR (PFG-NMR) and photochemical quenching techniques, was obtained in two extreme cases above and below the pore dimension of HA solution. Quantitative discussion that compares the obtained characteristic distance of diffusion with the pore size, clarifies the role of the nano-microstructure of HA solution forming small pores surrounded by the polymer chain networks.

The reactions in illuminated TiO2 nanocrystallite layers was studied by exposing them to pulsed laser photolysis in the presence and absence of added reactants. Results showed that the decay of absorption in the nanosecond time range is mainly due to gradual electron trapping, but the absorbance changes are not affected by scavengers. The trapping of electron was found to successfully compete with recombination even in the absence of scavengers.

Abstract Background Fluorescence correlation spectroscopy (FCS) provides information about translational diffusion of fluorescent molecules in tiny detection volumes at the single-molecule level. In normal states, cartilage tissue lacks vascularity, so chondrocyte metabolism depends on diffusion for molecular exchanges. The abundant extracellular matrix (ECM) of cartilage is maintained by a limited number of chondrocytes. ECM plays an important role in the regulation of chondrocyte functions. In this study, FCS was used to measure diffusion behaviors of albumin, the major protein of the intra-articular space, using normal and degenerated cartilage. Preliminary investigation of fluorescence dyes including Alexa 488, Rhodamine 6G and Rhodamine 123 was conducted to evaluate their properties in cartilage. Results The results indicate that the diffusion behaviors of fluorescently lableded albumin can be observed using FCS in both normal and chemically degenerated cartilage. Conclusions This work demonstrates the capability of FCS for direct measurement of diffusion in cartilaginous ECM. When the diffusion characteristics of fluorescent probes in ECM are clarified using FCS evaluation, FCS will be applicable as a method for early diagnosis of osteoarthritis, which is accompanied by increased abnormalities of ECM and also as tool for evaluating bio-engineered artificial cartilage for autologous chondrocyte implantation.

Abstract Background We aimed to study the effects of intra-articular injection of jellyfish mucin (qniumucin) on articular cartilage degeneration in a model of osteoarthritis (OA) created in rabbit knees by resection of the anterior cruciate ligament. Qniumucin was extracted from Aurelia aurita (moon jellyfish) and Stomolophus nomurai (Nomura's jellyfish) and purified by ion exchange chromatography. The OA model used 36 knees in 18 Japanese white rabbits. Purified qniumucin extracts from S. nomurai or A. aurita were used at 1 mg/ml. Rabbits were divided into four groups: a control (C) group injected with saline; a hyaluronic acid (HA)-only group (H group); two qniumucin-only groups (M groups); and two qniumucin + HA groups (MH groups). One milligram of each solution was injected intra-articularly once a week for 5 consecutive weeks, starting from 4 weeks after surgery. Ten weeks after surgery, the articular cartilage was evaluated macroscopically and histologically. Results In the C and M groups, macroscopic cartilage defects extended to the subchondral bone medially and laterally. When the H and both MH groups were compared, only minor cartilage degeneration was observed in groups treated with qniumucin in contrast to the group without qniumucin. Histologically, densely safranin-O-stained cartilage layers were observed in the H and two MH groups, but cartilage was strongly maintained in both MH groups. Conclusion At the concentrations of qniumucin used in this study, injection together with HA inhibited articular cartilage degeneration in this model of OA.

The distance dependence of the diffusion coefficient (DDDC) of a globular protein (cytchrome c) in aqueous hyaluronan (HA) solution, which is a model system for extracellular matrices (ECMs), was measured by a combination of three kinds of spectroscopic measurements of diffusion coefficients, the time and space samplings of which are different. The results of the three methods are plotted against the diffusion distance derived from the consideration of each experimental condition. Due to the characteristic morphology of HA with an effective mesh structure, the proteins showed two extreme diffusion modes: (1) short (<10 nm) diffusion with rare contact with polymer chains; (2) long (>100 nm) diffusion significantly disrupted by polymer chains showing an ≈30% reduction in diffusion coefficient. The transition from the short diffusion to the long one occurs in a very narrow range (10–100 nm) of diffusion distance and this unique character of HA realizing anomalous diffusion should provide suitable environments for various bioactivities when involved in ECM. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The increase in mobility of charge carriers in regioregular poly 3-hexyl thiophene (RR-P3HT) films by mixing them with tetracyanoethylene (TCNE), by in situ time-resolved microwave conductivity (TRMC) and transient optical spectroscopy (TOS) is examined. The result reveals that TCNE acts not only as an electron acceptor which increases the number of charge carriers on photoexposure, but also as a functional addictive which enhances the mobility of the charge carriers.

A study was conducted on the fluorescence fluctuation correlation function in structured fluids where the diffusion coefficients of probe molecules have different values depending on the distance from the initial position. Two simple expressions are derived which show a procedure to analyze the experimental data using time-dependent diffusion coefficient resulting from crossover from free diffusion inside a mesh to hindered diffusion through mesh structures.