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Classical statistical optics is revisited with the aim of introducing the concept of spatial statistical optics that places particular focus and special emphasis on spatial statistics of the optical field, rather than on their temporal statistics. The principles of emerging technology of statistical correlation holography based on spatial statistical optics are reviewed, and their unique capabilities for coherence and polarization shaping as well as synthesizing stochastic optical fields with desired statistical properties are introduced. [ABSTRACT FROM AUTHOR]

Phonon dispersions in ferroelectric lithium heptagermanate Li2Ge7O15 (LGO) were measured by inelastic neutron scattering in the vicinity of the transition temperature TC = 283.5 K. The (300) reflections show more pronounced temperature dependence than the (500) reflections. The energy of a peak corresponding to the Brillouin zone-center phonon, around 0.5 meV at 297.0 K, decreases as the temperature decreases. Then, this inelastic component disappears into the central component at 288.0 K, just above TC. The present phonon shows the typical soft mode feature and shows good accordance with the B1u mode observed by hyper-Raman and FTIR measurements. It is confirmed that the ferroelectric phase transition in LGO is associated with the soft optical phonon at the zone center. Moreover, elastic diffuse scattering is observed below 0.1 meV. This implies that there exists a critical phenomenon at energies below than 0.1 meV. [ABSTRACT FROM AUTHOR]

Abstract: Photonic fractal with self-similar structure of dielectric medium can strongly localize the electromagnetic wave energy in the three-dimensional fractal structure. We have fabricated Menger-sponge fractal structures of epoxy by using stereolithography. Titania–silica particles were dispersed into the epoxy to increase the dielectric constant and decrease the dielectric loss. The samples have square holes of 1, 3, 9 and 27mm in edge length through the cubic body of 81mm. Four types of Menger-sponge samples with fractal stages 1–4 were subjected for measurement of microwave responses. The both reflection and transmission amplitudes were attenuated simultaneously at frequencies of 9.5, 10.5, 12.0 and 13.5GHz for each sample with fractal stages 1, 2, 3 and 4, respectively. The electromagnetic field amplitudes in the air holes measured by inserting a mono-pole antenna probe confirmed the strong localization of the electromagnetic wave in the central air cavity. The localized mode frequency can be calculated using the sample size, number of stage, and the effective dielectric constant. The localization efficiency increased according to the fractal stage number. [Copyright &y& Elsevier]

Millimeter-order photonic crystals with the periodic arrangement of the dielectric constant were fabricated by infiltrating the mixed slurry of ceramics and polyester into the epoxy molds with an inverse form of a diamond structure. The epoxy molds are designed and processed by using a CAD/CAM process of stereolithography. The photonic crystals were prepared to have the diamond structure of the ceramic/polyester composite lattice, which is embedded in the epoxy matrix. The ceramic powders mixed with polyester are TiO2, SrTiO3, and BaTiO3 with high dielectric constant. It is possible to control more freely and widely the dielectric constant of the photonic crystals by this method. These ceramic/resin photonic crystals formed the complete photonic band gaps in the microwave band of 7–11 GHz, which can totally reflect the electromagnetic wave for all crystal directions. Attenuation profiles of the transmission amplitude in the band gaps were controlled with the dielectric constant of the composite lattice. The obtained results fairly agreed with the theoretical simulation of the electromagnetic wave propagation through photonic crystals. [Copyright &y& Elsevier]

Abstract: Fibroblast growth factor receptor (FGFR) is expressed in a variety of cells and is involved in their proliferation/migration/survival. To elucidate FGFR-mediated specific action of vascular endothelial cells (ECs) on myocardial ischemia, we generated endothelium-targeted transgenic mice overexpressing constitutively active FGFR2 using Tie2 promoter (FGFR2-Tg). Infarct size, vessel formation and blood perfusion were significantly improved 28 days after myocardial infarction (MI) in FGFR2-Tg, compared with wild-type mice. Aortic ECs isolated from FGFR-Tg showed a marked increase in migratory capacity and tube formation. These in vitro angiogenic activities were blocked by PI3-kinase inhibitor. Whereas, parameters obtained from echocardiography were already improved at three days after MI. Cardiomyocyte apoptosis at the ischemic border zone was decreased in FGFR2-Tg (32.1%, p <0.05) and cardiac mRNA expression of FGF2 (basic FGF) was also up-regulated (142%, p <0.05) at 3 days after MI. 1% oxygen-mediated apoptosis was significantly inhibited in FGFR2-Tg-ECs and this inhibition was abolished by PI3-kinase inhibitor. FGFR2-Tg-ECs exposed to 1% oxygen exhibited enhanced phosphorylation of 416-Tyr-Src, 473-Ser-Akt, and HIF1α accumulation. The production of FGF2 was enhanced 2.1-fold in FGFR-Tg-ECs under 1% oxygen via the Src/Akt/HIF1α pathway, which induced the peri-vessel migration of vascular smooth muscle cells (VSMCs) and anti-apoptotic effects on VSMCs and cardiomyocytes. FGF receptor signaling in ECs promoted migration, survival and autocrine production of FGF2, leading to reduced infarct size, which is associated with anti-apoptotic action in the early stage and with enhanced angiogenesis in the late stage after MI. [Copyright &y& Elsevier]

Objective. Nitric oxide (NO) is known to act as a mediator of tissue injury as well as being a potent endogenous vasodilator. The functional and metabolic effects of NO on ischemia-reperfusion injury are still controversial. The aim of this study was to clarify the relationship between the degree of NO synthase (NOS) inhibition and the effects on ischemia-reperfusion injury. Methods and results. Langendorff-perfused rat hearts were subjected to 30 minutes of global ischemia followed by 30 minutes of reperfusion. The recovery of left ventricular developed pressure (LVDP), creatine kinase (CK) release, and myocardial high energy phosphates were measured in hearts perfused with or without NOS inhibitors, L-NG-monomethyl arginine (L-NMMA) or NGnitro-L-arginine methylester (L-NAME). NOS inhibitors exerted different effects on the recovery of LVDP and CK release depending on the concentration. The low dose of L-NMMA improved the recovery of LVDP, decreased the CK release during reperfusion, and preserved the myocardial adenosine triphosphate content after reperfusion. In contrast, the high dose of L-NMMA had adverse effects. L-NMMA reduced NO release in coronary effluent in a dose-dependent fashion. Both effects of L-NMMA were abolished by excessive co-administration of L-arginine and the same doses of D-NG-monomethyl arginine (D-NMMA) showed no effect on ischemia-reperfusion injury. Therefore, both effects were due to NOS inhibition. In addition, L-NMMA suppressed the myocardial malondialdehyde accumulation, an indicator of oxidative stress, which might be attributed to the beneficial effects by partial NOS inhibition. On the other hand, the high dose L-NMMA significantly decreased coronary flow during aerobic perfusion and reperfusion. Therefore, it is conceivable that the vasoactive NOS inhibition contributes to the harmful effects, which might exceed the beneficial effects due to a decrease in oxidative stress. Conclusion. The present results showed that NO inhibitors had dual effects on mechanical function and energy metabolism depending on the concentration. Non-vasoactive inhibition of NOS had beneficial effects due to the suppression of oxidative injury. However, strong vasoactive inhibition of NOS exacerbated the ischemia-reperfusion injury. [ABSTRACT FROM AUTHOR]

This paper reports the first application of the terahertz time domain spectroscopy to phonon polariton dispersion. In order to determine polariton-dispersion of a high-quality ferroelectric bismuth titanate crystal plate, the phase delay was determined minutely as a function of THz radiation frequency in the region between 3 cm -1 and 100 cm -1 . The polarization dependence of polariton dispersion was clearly observed on the c-plate only by switching the polarization of an incident beam from E//a to E//b. The observed polariton dispersion relations are consistently explained by the calculation using Kurosawa's formula. [ABSTRACT FROM AUTHOR]

We study the effect of a dielectric film attached to the surface of a metal hole array (MHA) on the reflection spectrum in the terahertz (THz) region. The frequency of the reflection dip, attributed to the excitation of surface waves in the vicinity of the MHA surface, shifts to lower frequencies with increasing dielectric film thickness. This resonant characteristic of MHAs can be applied to highly sensitive THz sensing for samples attached to the MHA surface. We also investigate the dependence of the reflection spectrum on the MHA’s thickness and the side to which the dielectric film is attached. [ABSTRACT FROM AUTHOR]

Abstract The surface polarization scattering is investigated in terms of the coherence matrix for the electric field scattered from a birefringent material with a random interface between its surface and air. The relationship between the statistical properties of the scattered light at the scattering surface and the micro-structure of the anisotropic media has been explored for the first time to understand the underlying mechanism of the surface scattering phenomena for the electric field with random states of polarization. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate control over the group delay of narrow-band (quasi continuous wave) terahertz (THz) pulses with constant amplitude based on optical switching of a metasurface characteristic. The near-field coupling between resonant modes of a complementary split ring resonator pair and a rectangular slit show an electromagnetically induced transparency-like (EIT-like) spectral shape in the reflection spectrum of a metasurface. This coupling induces group delay of a narrow-band THz pulse around the resonant frequency of the EIT-like spectrum. By irradiating the metasurface with an optical excitation pulse, the metasurface becomes mirror-like and thus the incident narrow-band THz pulse is reflected without a delay. Remarkably, if we select the appropriate excitation power, only the group delay of the narrow-band THz pulse can be switched while the amplitude is maintained before and after optical excitation. [ABSTRACT FROM AUTHOR]

The detailed phase distribution of an astigmatic optical beam with inverting vortex is measured with a polarization based phase shifting interferometry. Energy flows and angular momentum density distribution within the beam cross sections are calculated from experimental data. Positive and negative angular momentum regions are observed both before and after vortex inversion, and regions of pure radial flow are identified. [ABSTRACT FROM AUTHOR]

Raster scan systems can introduce cubic and quadratic phase distortions in holograms for generating and detecting doughnut beams. The distortions can be corrected by subtracting corresponding terms from the hologram design. The compensation parameters can be determined by fabricating test holograms and applying rotational symmetry analysis to the intensity distribution of the generated beams. The 2- and 3-fold rotational symmetry components are shown to be effective in determining quadratic and cubic corrections respectively, and in the final corrected hologram the total contribution of anisotropic intensity components was reduced to 0.3%. [ABSTRACT FROM AUTHOR]

We experimentally controlled the spectral characteristics of the extraordinary transmissions observed in metal hole arrays by analogy with spoof surface plasmon-polaritons (spoof SPPs). We constructed doubly periodic metal hole arrays. The larger and smaller periodic holes are for inducing extraordinary transmissions and modifying the spoof SPPs' characteristics, respectively. Introducing the smaller holes that surround the larger hole arrays can modify the dispersion curve of the surface waves excited on a structured metal surface analogous to the spoof SPP model, and consequently, the extraordinary transmission peak will show a redshift. [ABSTRACT FROM AUTHOR]

Experience of primary percutaneous coronary intervention (PCI) for young adults with acute myocardial infarction (AMI) due to sequelae of Kawasaki disease (KD) has been extremely limited. In the present report on three young adults (two males and one female; age 20-35 years) with AMI, we performed primary PCI and intravascular ultrasound imaging (IVUS). Case 1 underwent thrombectomy alone in the proximal left circumflex coronary artery, and subsequent IVUS depicted a large aneurysm with an asymmetrically intimal thickening and a residual thrombus in the culprit. Case 2 underwent balloon dilation with adjunctive intracoronary thrombolysis in the proximal left anterior descending coronary artery (LAD), and IVUS during follow-up coronary angiography (CAG) delineated a regressed giant aneurysm with a markedly intimal thickening in the culprit. Case 3, with past history highly suggesting KD, underwent balloon dilation in the proximal LAD, and follow-up CAG as well as IVUS revealed a neoaneurysmal formation in the culprit. In all of the patients, PCI was angiographically effective at the acute phase without complication. Follow-up CAG performed 3-6 months after the procedure revealed no restenosis in all three cases, but a new coronary aneurysm still remained in case 3. Although case 1 and case 2 had no obvious history of KD, the vessel wall morphology from IVUS closely resembled the coronary sequelae after KD, suggesting that they might have antecedent incomplete KD. These cases suggest that primary PCI against coronary sequelae of KD in young AMI patients might be safe and effective in the short term. [ABSTRACT FROM AUTHOR]

Members of the fibroblast growth factor (FGF) family have been clinically applied to the treatment of ischemic diseases because of their strong angiogenic actions. Although tissue ischemia is predominantly caused by atherosclerosis, the roles of endothelial FGF receptors (FGF-Rs) in atherosclerosis remain obscure. We generated endothelial cell (EC)-targeted constitutively active FGF-R2-overexpressing mice, using the Tie2 promoter (Tie2-FGF-R2-Tg), and crossed them with apolipoprotein E (ApoE)-deficient mice (ApoE-KO) to generate Tie2-FGF-R2-Tg/ApoE-deficient mice (Tie2-FGF-R2-Tg/ApoE-KO). After being fed a Western diet for 8 wk, the Tie2-FGF-R2-Tg/ApoE-KO demonstrated 2.0-fold greater atherosclerotic lesion area on the luminal surfaces of the aortas than the ApoE-KO (P < 0.01). The level of p21Cip1 protein, a cell cycle inhibitor, in the FGF-R2-overexpressing EC was 2.5-fold greater than that in the wild-type (WT) EC at the baseline (P < 0.01). FGF-R2 overexpression in the EC resulted in increased expression of VCAM-1 and ICAM-1, acceleration of apoptosis, and decreased proliferative activity, all of which were normalized by small interfering RNA (siRNA)-mediated knockdown of p21Cip1 (75% reduction in protein level, P < 0.01). Furthermore, the expression of PDGF-B and Egr-1, a PDGF/p21Cip1-inducible transcription factor, in the aortic endothelium of Tie2-FGF-R2-Tg/ApoE-KO was significantly greater than that in ApoE-KO. The proliferation of vascular smooth muscle cells in the aortic media of Tie2-FGF-R2-Tg/ApoE-KO was 2.0-fold higher than that in ApoE-KO (P < 0.01). Thus our study reveals that endothelial FGF-R2 signaling aggravates atherosclerosis by promoting p21Cip1-mediated EC dysfunction and cautions against the use of FGF for therapeutic angiogenesis in the setting of atherosclerosis. [ABSTRACT FROM AUTHOR]

Abstract: Nicorandil has been shown to inhibit myocyte apoptosis by opening of mitochondrial ATP-sensitive potassium (mitoKATP) channels and nitrate-like effect against oxidative stress. However, the detailed mechanism of nicorandil-mediated cardioprotection under hypoxic conditions remains to be largely unknown. The present study examined whether nicorandil can inhibit apoptosis via regulation of Bcl-2 family proteins in hypoxic myocytes. Neonatal rat cardiac myocytes were exposed to hypoxia for 7 hours. Hypoxia-induced myocyte apoptosis (13.9±0.9%) under glucose-rich conditions. Myocyte apoptosis was accompanied by loss of mitochondrial membrane potential (Δψm), cytochrome c release from mitochondria into cytosol, and activation of caspase-3. Hypoxia also significantly increased Bax and decreased Bcl-2 mRNA and protein expression, thereby increasing Bax/Bcl-2 ratio. Nicorandil 100 μmol/l significantly decreased the percentage of apoptotic myocytes (7.2±0.5%) by inhibiting loss of Δψm and translocation of cytochrome c. These effects of nicorandil were partially but significantly inhibited by cotreatment of either 500 μmol/l 5-hydroxydecanoate, a selective mitoKATP channel antagonist, or 10 μmol/l 1H-[1,2,4]oxidazolo[4,3-a]quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase. Moreover, nicorandil significantly inhibited the hypoxia-induced changes in Bax and Bcl-2 expression, and concomitant increased Bax and decreased Bcl-2 immunoreactivity in mitochondria. These effects of nicorandil in Bax and Bcl-2 expression were significantly blunted by cotreatment of ODQ and 5-HD, respectively. Cotreatment of KT5823, an inhibitor of protein kinase G, significantly blocked the effect of nicorandil on Bax expression and 8-bromo-cyclic guanosine 3′,5′ monophosphate (8-bromo-cGMP), a cGMP analog, mimicked the effect of nicorandil on Bax expression. The present study demonstrates that nicorandil regulates Bcl-2 family proteins via opening of mitoKATP channels and nitric oxide-cGMP signaling and inhibits hypoxia-induced mitochondrial death pathway. [Copyright &y& Elsevier]

Abstract: The phase-crossing algorithm is proposed for white-light interferometry, which uses the multi-color phase information of spectrally decomposed interferograms recorded simultaneously with color-sensitive image sensors. The location of zero optical path difference is identified as the singular point at which the phase becomes color invariant, and is determined accurately with a sub-sampling-interval resolution from the crossing point of the multi-color phase distributions obtained by the Fourier transform method. An experimental result is presented that demonstrates the performance of the phase-crossing algorithm. [Copyright &y& Elsevier]

Three-dimensional photonic crystals with a diamond lattice structure consisting of 5 × 5 × 5 unit cells with the unit cell dimension of 15 mm were fabricated using TiO2-based ceramic particles dispersed epoxy by stereolithography. The diamond lattice showed a perfect band gap between 14.3 and 15.8 GHz. An air cavity defect with a rectangular shape (15 mm × 45 mm × 15 mm) was introduced at the center of the crystal by extracting 3 unit cells in order to investigate the shape effect of the defect on the formation of localized defect modes of electromagnetic wave. When microwaves were radiated normal to the wide sides (45 mm × 15 mm) of the rectangular shape defect, a sharp localized mode appeared at the middle of the band gap. However, no localized mode was observed for incident waves normal to the smaller side (15 mm × 15 mm) because of the symmetry mismatching between internal eigenmodes in the defect cavity and incident plane waves. The mode analysis using a simple cavity model showed the penetration of the electric field of resonant modes about 2.4 mm into the host lattice. [ABSTRACT FROM AUTHOR]

Abstract: Rather than regarding the phase singularities as obstacles or nuisances in phase unwrapping, we explore new possibilities of making use of the phase singularities in optical metrology. Instead of intensity correlation techniques used in conventional speckle metrology, we propose a new technique of displacement measurement that makes use of the density of phase singularities in the complex analytic signal of the speckle pattern, which is generated by Hilbert filtering. Experimental results and theoretical analysis are presented that demonstrate the validity of the proposed technique. [Copyright &y& Elsevier]

Complex polariton dispersion relations were determined in the congruent lithium niobate crystal using the latest terahertz time domain spectroscopy. We measured the power and phase transmission spectra by the coherent THz radiation. The complex dispersion relations of phonon polariton frequency and damping have been investigated simply by rotating the polarization plane of an incident beam. These dispersive properties have been consistently reproduced by the damped harmonic oscillator model related to the lowest frequency infrared active modes. [ABSTRACT FROM AUTHOR]

A new concept of smart processing is proposed that can produce advanced materials and components by finely controlling processing energy and engineering structures. New functional components of 3D photonic crystals and fractals are demonstrated, which are constructed of dielectric ceramics and a polymer using a CAD/CAM stereolithography system. By modifying the structure of diamond-like photonic crystals using free-form fabrication, electromagnetic waves can be controlled, opening the way for new applications in communication and sensing technology. The photonic fractal, a new material that can strongly localize electromagnetic waves without reflection and transmission, will also lead to new applications in the energy and medical fields. [ABSTRACT FROM AUTHOR]

Photonic crystals with a diamond structure of epoxy lattices in which TiO[sub 2]-based ceramic particles are dispersed were fabricated by stereolithography. The periodicity of the lattice was designed to reflect electromagnetic waves in the gigahertz range. The volume fraction (β) of the dielectric lattice medium was modified from 14% to 33% by changing the rod diameter of the lattice. The photonic band gap was observed along Γ-L 〈111〉, Γ-X 〈100〉, and Γ-K 〈110〉 directions and the complete photonic band gap was formed at over β = 20%. The width of the forbidden gap increased gradually when the β increased over 14%, and reached 2.4 GHz at β = 33%. These results agreed with the band calculation using the plane wave expansion method. [ABSTRACT FROM AUTHOR]

Three-dimensional electromagnetic or photonic crystals with periodic variations of the dielectric constants were fabricated by a rapid prototyping method called stereolithography. Millimeter-order epoxy lattices with a diamond structure were designed to reflect electromagnetic waves by forming an electromagnetic bandgap in the GHz range. Titanium oxide-based ceramic particles were dispersed into the lattice to control the dielectric constant, resulting in the formation of narrow and deep bandgaps. Crystals of the inverse form that have a network of holes with the diamond structure in a dielectric matrix were successfully fabricated as well. These inverse diamond structures formed the perfect bandgap reflecting electromagnetic waves for all directions. The location of the bandgap agreed with the band calculation using the plane wave propagation method. [Copyright &y& Elsevier]

Optical switching of the spectrum and polarization of terahertz radiation from split-ring resonator-loaded photoconductive antennas has been demonstrated. The switching is based on the sensitivity of the resonance of a split-ring resonator on a photoconductive substrate to a change in the capacitance induced by optical pulse irradiation. The spectral and polarization characteristics of the split-ring resonator-loaded photoconductive antennas are discussed in terms of the coupling between the electric dipole induced by the pump laser and the eigenmodes of the split-ring resonators. [ABSTRACT FROM AUTHOR]

We show that the terahertz resonant transmission through metal hole array can be tailored by filling the holes with metamaterials. Experiment and finite difference time domain simulations show this type of resonant transmission to be induced by locally resonant modes, instead of the usual lateral surface grating mode. As the metamaterial's local resonances can be manipulated by varying their geometric configurations, this type of resonant transmission can be tuned over a broad frequency regime that is subwavelength to the array periodicity, with a transmission profile that can also be tailored by the frequency location of the resonance. Such tunability of resonant transmission, with its attendant enhanced local field intensity in the vicinity of the aperture, may provide some potential applications. [ABSTRACT FROM AUTHOR]

Three-dimensional bulk metamaterials that operate in the terahertz (THz) frequency range were fabricated by stacking 100 two-dimensional sheets containing metallic split-ring resonators (SRR) on thin polyethylene terephthalate film substrates. The THz magnetic resonance for the incident magnetic field perpendicular to the plane of the SRR structure was measured. We also investigated the dependence of the magnetic resonant strength on the metal thickness. [ABSTRACT FROM AUTHOR]