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An effective measuring method for characterizing the planar periodic structure on specimen surface, i.e., inverse laser scanning confocal microscopy moiré method, is presented and verified by experiments in this paper. The planar character of the periodic surface structure in a large region of several hundreds of millimeters, as well as the dimension at micro- and nanoscales, can be obtained through seeking the specimen grating equation as well as the virtual strain distribution. Verification experiment is carried out using a 1200 lines/mm holography grating as the specimen. The calculated results are in good coincidence with the actual character, demonstrating the validity, feasibility, and high accuracy of this method. Applying this method into identifying the structure of butterfly wing, gratings composed of a cluster of curves with pitches of a little less than 438 nm are found on multiscales of butterfly wing, which provides the possibility for further explaining its attractive iridescence. Furthermore, this method is greatly promising for providing simple, reliable support for bionics, grating fabrication, and maybe the sliding mechanism of crystal lattice. [ABSTRACT FROM AUTHOR]

Prostaglandin E2 (PGE2) plays crucial roles in managing microglial activation through the prostanoid EP2 receptor, a PGE2 receptor subtype. In this study, we report that PGE2 enhances interferon-γ (IFN-γ)-induced nitric oxide production in microglia. IFN-γ increased the release of nitrite, a metabolite of nitric oxide, which was augmented by PGE2, although PGE2 by itself slightly affects nitrite release. The potentiating effect of PGE2 was positively associated with increased expression of inducible nitric oxide synthase. In contrast to nitrite release induced by IFN-γ, lipopolysaccharide-induced nitrite release was not affected by PGE2. An EP2 agonist, ONO-AE1-259-01 also augmented IFN-γ-induced nitrite release, while an EP1 agonist, ONO-DI-004, an EP3 agonist, ONO-AE-248, or an EP4 agonist, ONO-AE1-329, did not. In addition, the potentiating effect of PGE2 was inhibited by an EP2 antagonist, PF-04418948, but not by an EP1 antagonist, ONO-8713, an EP3 antagonist, ONO-AE3-240, or an EP4 antagonist, ONO-AE3-208, at 10−6 M. Among the EP agonists, ONO-AE1-259-01 alone was able to accumulate cyclic adenosine monophosphate (AMP), and among the EP antagonists, PF-04418948 was the only one able to inhibit PGE2-increased intracellular cyclic AMP accumulation. On the other hand, IFN-γ promoted phosphorylation of signal transducer and activator of transcription 1, which was not affected by PGE2. Furthermore, other prostanoid receptor agonists, PGD2, PGF2α, iloprost, and U-46119, slightly affected IFN-γ-induced nitrite release. These results indicate that PGE2 potentiates IFN-γ-induced nitric oxide production in microglia through the EP2 receptor, which may shed light on one of the pro-inflammatory aspects of PGE2. [ABSTRACT FROM AUTHOR]

Spot moiré fringes are generated by the superposition between a nanoporous structure and a digital three-way grating. The spot moiré fringes are useful for the characterization of the domain boundaries and structural parameters in ordered nanoporous materials. The pitches and the orientations of the nanopore arrays in three directions can be simultaneously determined in a large view field. [ABSTRACT FROM AUTHOR]

In this study, the residual stress in a resist (PAK01) film and the stress intensity factor (SIF) of an induced crack are simultaneously estimated during ultraviolet nanoimprint lithography (UV-NIL) based on electron moir'e fringes. A micro grid in a triangular arrangement on the resist film fabricated by UV-NIL is directly used as the model grid. Electron moir'e fringes formed by the interference between the fabricated grid and the electron scan beam are used to measure the displacement distribution around the tip of a crack induced by the residual stress in the resist. The SIF of the crack is estimated using a displacement extrapolation method. The residual strain fields and the corresponding residual stress in the resist film far from the crack are determined and analyzed. This method is effective for evaluating the grid quality fabricated by the UV-NIL technique. [ABSTRACT FROM AUTHOR]

Structural information such as domain sizes and orientation directions in ordered assembled nanoparticles can be simultaneously obtained by using generated electron Moiré fringes, without direct observation of the nanoparticles. [ABSTRACT FROM AUTHOR]

Recently, the thermal-spray community has focused considerable attention on cold-spray and warm-spray techniques, in which the temperatures of sprayed particles are kept below their melting point and adhesion occurs based on the impact phenomenon between a solid particle and a substrate. The mechanisms of adhesion are still unclear, but the degree of the mechanical deformation at the interface is considered to be a key factor influencing this mechanism. However, it is very difficult to directly measure the strain at the interface. Instead, in this work, the strain fields on a substrate around an impacted particle sprayed by warm-spray deposition were measured by applying electron Moiré method, and compared with numerical simulation results. [ABSTRACT FROM AUTHOR]

By integrating moiré method with laser scanning confocal microscopy (LSCM), a novel class of moiré patterns, i.e., LSCM moiré patterns, is presented and investigated by experiment in this article. The moiré patterns are formed by the interference of a 1200 line/mm cross-line holographic grating and the scanning lines of LSCM. The principles and conditions of forming LSCM moiré are described in detail. The measured parameters of moiré fringes from experimental images agree well with theoretical analysis. The experimental results verify the feasibility and reality of the proposed moiré method to be another effective and high accuracy technique for measuring and observing in-plane microdeformation at micrometer scale. [ABSTRACT FROM AUTHOR]

The dynamic deformations of impulsed viscoelastic plates measured with the moire method are discussed. A new method for producing visco-photoelastic material is proposed. The material was processed as plate type specimens with elliptical or circular holes, and utilized to investigate its dynamic deformation behavior at 42°C. The measuring method and procedures, as well as the experimental results are discussed in detail. [ABSTRACT FROM PUBLISHER]