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The thickness of the dura mater in the human cervical spine can vary between individuals and by vertebral level; these differences can result in various clinical outcomes. The purpose was to measure and analyze cervical dura mater thickness. Microscopic measurements were made of tissue from human cadavers. The subjects were nine human cadavers with no previous history of spinal deformity or surgery. Fourteen segments of both anterior and posterior dura mater from the C1 to C7 cervical vertebrae were obtained. Dura mater thickness was measured using an infrared laser-based confocal microscope. Statistical analyses were performed to examine the relationships of cervical dura mater thickness with vertebral level, age, and sex. The overall average cervical dura mater thickness was 379.3 × 10−3 mm. Statistically significant differences in thickness were found between the anterior and posterior segments (P < 0.0001). Moreover, the thickness at each vertebral level was significantly different from the thicknesses at the other levels (P < 0.05). The posterior dura mater thickness was highest at C1 and lowest at C5/6. Posterior dura mater thickness was significantly different at the axial, sub-axial, and lower cervical levels, whereas anterior dura mater thickness was relatively constant among levels. A significant correlation was found between thickness and age (P < 0.05); however, the average dura mater thickness was not significantly different between males and females. This study shows anatomical differences in cervical dura mater thickness with respect to vertebral level and age. These results provide anatomical information that will inform basic research and clinical approaches. [ABSTRACT FROM AUTHOR]

A micro-beam scanning X-ray photoelectron spectroscopy (XPS) has been utilized to obtain information about the attachment of ligand to nanoparticles in solution by measuring the ligand components relative to nanoparticle components. CdSe/ZnS core/shell nanoparticles capped with three different kinds of ligand molecules are drop-casted on a substrate and led to dry into self-agglomerated micropatterns. Those specimens are mapped out by element-sensitive XPS imaging. The spatial correlation between surface ligand molecules and core nanoparticle atoms is statistically analysed using Pearson correlation function, which provides with a useful assessment of the ligand binding to nanoparticle surfaces. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The excited-state intramolecular proton-transfer-induced charge transfer of semirigid polyquinoline (PQH) is explored in 1,1,2,2-tetrachloroethane (TCE) and N-methyl-2-pyrrolidinone (MP) using picosecond time-resolved fluorescence spectroscopy. Reaction mechanisms are found to depend on the rotational conformations of PQH at the moment of excitation; whereas the trans-enolic form does not undergo intramolecular proton transfer within its excited-state lifetime, the cis-enolic form does within 15 ps to form a tautomeric zwitterion species. While the subsequent intramolecular charge transfer of the zwitterionic species to yield a tautomeric keto species takes place on time scales of 25 ps in TCE ( ε = 8.50) and 62 ps in MP ( ε = 32.55), its reverse reaction is also followed on time scales of 28 ps in TCE and 20 ps in MP. The lack of a kinetic isotope effect in both forward and reverse charge-transfer reactions support our proposed mechanisms. [ABSTRACT FROM AUTHOR]

The article discusses the use of Prussian blue for synthesis of Mesoporous Iron Oxide Particles, which are mostly composed of inorganic substances. Topics include significance of metal organic frameworks (MOFs) as catalyst, synthesis of monodisperse Prussian blue (PB), and use of hydrothermal synthesis.

Individual silver nanoparticle-conjugated target protein (cTnI) molecules on gold-nanopatterned chip were selectively detected by wavelength dependent-enhanced dark field illumination. Using specific nanoparticles with unique sizes and materials, the immunotargeted nanoparticle on the chips was detected at the single-molecule level by monitoring changes in the plasmonic resonance based on wavelength dependence. [ABSTRACT FROM AUTHOR]

A new molecular structure of azobenzene, which can be reduced to the corresponding anilines at a low reduction potential for the site-selective immobilization of biomolecules, is proposed. Redox-active species, enzymes, peptides, and cultured hippocampal neurons can be effectively immobilized on the electrochemically activated surface. [ABSTRACT FROM AUTHOR]

Scanning acoustic microscopy (SAM) or Acoustic Micro Imaging (AMI) is a powerful, non-destructive technique that can detect hidden defects in elastic and biological samples as well as non-transparent hard materials. By monitoring the internal features of a sample in three-dimensional integration, this technique can efficiently find physical defects such as cracks, voids, and delamination with high sensitivity. In recent years, advanced techniques such as ultrasound impedance microscopy, ultrasound speed microscopy, and scanning acoustic gigahertz microscopy have been developed for applications in industries and in the medical field to provide additional information on the internal stress, viscoelastic, and anisotropic, or nonlinear properties. X-ray, magnetic resonance, and infrared techniques are the other competitive and widely used methods. However, they have their own advantages and limitations owing to their inherent properties such as different light sources and sensors. This paper provides an overview of the principle of SAM and presents a few results to demonstrate the applications of modern acoustic imaging technology. A variety of inspection modes, such as vertical, horizontal, and diagonal cross-sections have been presented by employing the focus pathway and image reconstruction algorithm. Images have been reconstructed from the reflected echoes resulting from the change in the acoustic impedance at the interface of the material layers or defects. The results described in this paper indicate that the novel acoustic technology can expand the scope of SAM as a versatile diagnostic tool requiring less time and having a high efficiency. [ABSTRACT FROM AUTHOR]

Super-resolution imaging of fluorescence-free plasmonic nanoparticles (NPs) was achieved using enhanced dark-field (EDF) illumination based on wavelength-modulation. Indistinguishable adjacent EDF images of 103-nm gold nanoparticles (GNPs), 40-nm gold nanorods (GNRs), and 80-nm silver nanoparticles (SNPs) were modulated at their wavelengths of specific localized surface plasmon scattering. The coordinates (x, y) of each NP were resolved by fitting their point spread functions with a two-dimensional Gaussian. The measured localization precisions of GNPs, GNRs, and SNPs were 2.5 nm, 5.0 nm, and 2.9 nm, respectively. From the resolved coordinates of NPs and the corresponding localization precisions, super-resolution images were reconstructed. Depending on the spontaneous polarization of GNR scattering, the orientation angle of GNRs in two-dimensions was resolved and provided more elaborate localization information. This novel fluorescence-free super-resolution method was applied to live HeLa cells to resolve NPs and provided remarkable sub-diffraction limit images. [ABSTRACT FROM AUTHOR]

A nanoimmunosensor based on wavelength-dependent dark-field illumination with enhanced sensitivity was used to detect a disease-related protein molecule at zeptomolar (zM) concentrations. The assay platform of 100-nm gold nanospots could be selectively acquired using the wavelength-dependence of enhanced scattering signals from antibody-conjugated plasmonic silver nanoparticles (NPs) with on–off switching using optical filters. Detection of human thyroid-stimulating hormone (hTSH) at a sensitivity of 100 zM, which corresponds to 1–2 molecules per gold spot, was possible within a linear range of 100 zM–100 fM ( R =0.9968). A significantly enhanced sensitivity (~4-fold) was achieved with enhanced dark-field illumination compared to using a total internal reflection fluorescence immunosensor. Immunoreactions were confirmed via optical axial-slicing based on the spectral characteristics of two plasmonic NPs. This method of using wavelength-dependent dark-field illumination had an enhanced sensitivity and a wide, linear dynamic range of 100 zM–100 fM, and was an effective tool for quantitatively detecting a single molecule on a nanobiochip for molecular diagnostics. [ABSTRACT FROM AUTHOR]

The article discusses the use of Prussian blue for synthesis of Mesoporous Iron Oxide Particles, which are mostly composed of inorganic substances. Topics include significance of metal organic frameworks (MOFs) as catalyst, synthesis of monodisperse Prussian blue (PB), and use of hydrothermal synthesis.