Electron tomography (ET) has recently afforded new insights into neuronal architecture. However, the tedious process of sample preparation, image acquisition, alignment, back projection, and additional segmentation process of ET repels beginners. We have tried Hitachi's commercial packages integrated with a Hitachi H-7650 TEM to examine the potential of using an automated fiducial-less approach for our own neuroscience research. Semi-thick sections (200–300 nm) were cut from blocks of fixed mouse (C57BL) cerebellum and prepared for ET. Sets of images were collected automatically as each section was tilted by 2° increments (±60°). “Virtual” image volumes were computationally reconstructed in three dimension (3D) with the EMIP software using either the commonly used “weighted back-projection” (WBP) method or “topography-based reconstruction” (TBR) algorithm for comparison. Computed tomograms using the TBR were more precisely reconstructed compared with the WBP method. Following reconstruction, the image volumes were imported into the 3D editing software A-View and segmented according to synaptic organization. The detailed synaptic components were revealed by very thin virtual image slices; 3D models of synapse structure could be constructed efficiently. Overall, this simplified system provided us with a graspable tool for pursuing ET studies in neuroscience.

At the apical tip of Drosophila testis, there is a stem cell niche known as the proliferation center, where the stem cells are maintained by hub cell cluster for the regulation of differentiation and proliferation. Germline stem cells go through mitosis four times from one primary spermatogonial cell to the 16-cell stage before the maturation. The cells derived from the same germline stem cell are located within one cyst, an enclosed system by two cyst cells, and they are connected by the intercellular bridges called ring canals. In this study, the three-dimensional (3D) structure of Drosophila testis tip was reconstructed from serial sections. The size of cells at each stage was compared in volume from the 3D structure. The stages of cells in a cyst could be distinguishable exactly by counting the cells linked with intercellular bridges in 3D-reconstructed structure. The cysts containing the same stage cells appeared in the horizontal plane. Both the germline stem cell directly attached to the hub cell and the spermatogonial cells detached from the hub cell were divided at the almost perpendicular direction to the spermatogonial cell layers. The dividing phase in one cyst was delayed gradually through the cytoplasmic region of intercellular bridge.

The “LEXT” confocal laser scanning microscope has been used for the three-dimensional (3D) imaging of the surface of specimens, especially in materials science fields, by the penetration of near-infrared (NIR) light without mechanical cutting, deposition, or other specimen pretreatment. Noninvasive investigation of various biological tissues such as human spinal dura mater, rat aorta, and cornea without the dehydration process was successfully carried out with the “LEXT,” in order to access both surface and internal topographic images of the biological structures at a good status of the wet tissue such as in vivo, especially in measuring tissue thickness. The confocal NIR laser microscopy offers the viable means to visualize tissue architecture and its thickness in microdomain to integrate 3D images efficiently. We believe that the “LEXT” has a good application for biological researchers to study biomaterials, and it would be useful as a diagnostic tool in the near future.

We report the synthesis of carbon nanowires (CNWs) via chemical vapor deposition using catalytic decomposition of ethanol on nanosized transition metals such as Co, Fe, and Ni. Dip-coating process was used for the formation of catalytic nanoparticles, inducing the growth of CNWs on the surface of the carbon fiber paper (CFP). The liquid ethanol used as carbon source was atomized by an ultrasonic atomizer and subsequently flowed into the reactor that was heated up to a synthesis temperature of 600–700°C. Microscopic images show that CNWs of <50 nm were densely synthesized on the surface of the CFP. Raman spectra reveal that a higher synthesis temperature leads to the growth of higher crystalline CNWs. In addition, we demonstrate the successful decoration of platinum nanoparticles on the surface of the prepared CNWs/CFP using the electrochemical deposition technique.

The oxidation mechanism and thermal stability of nickel oxide (NiO)/carbon nanotube (CNT) composites were investigated by examining composites with different NiO contents by thermogravimetric analysis and transmission electron microscopy (TEM). NiO acts as a catalyst in the oxidation of CNT in the composite. CNTs can be oxidized, even in a vacuum, by reducing NiO to nickel at temperatures lower than the normal oxidation temperature of CNTs. This phase transition was confirmed directly by in situ heating TEM observations. In air, reduction by CNT occurs simultaneously with reoxidation by gaseous O2 molecules, and NiO maintains its phase. The thermal stability decreased with increasing NiO content because of defects in the CNT generated by the NiO loading.

International standard ISO-25498 specifies the method of selected area electron diffraction (SAED) analysis in TEM. It is applicable to the acquisition of SAED patterns, indexing the patterns and calibration of diffraction constant. Several features of this standard are introduced. As an example of the applications, phosphide with nanometer scale in a low-carbon steel produced by compact strip production process was analyzed by SAED and EDX. The phosphide precipitates in the steel are identified as MxP, where x is 2–3 and M is Fe, Ti, Cr, or Ni. It possesses a hexagonal lattice with lattice parameter a = 0.609 nm and c = 0.351 nm.

The in vitro corrosion mechanism of the biodegradable cast Mg–10% Ca binary alloy in Hanks' solution was evaluated through transmission electron microscopy observations. The corrosion behavior depends strongly on the microstructural peculiarity of Mg2Ca phase surrounding the island-like primary Mg phase and the fast corrosion induced by the interdiffusion of O and Ca via the Mg2Ca phase of lamellar structure. At the corrosion front, we found that a nanosized crack-like pathway was formed along the interface between the Mg2Ca phase and the primary Mg phase. Through the crack-like pathway, O and Ca are atomically exchanged each other and then the corroded Mg2Ca phase was transformed to Mg oxides. The in vitro corrosion by the exchange of Ca and O at the nanosized pathway led to the rapid bulk corrosion in the Mg–Ca alloys.