Heat-resistant DNA tile arrays constructed by template-directed photoligation through 5-carboxyvinyl-2′-deoxyuridine

Template-directed DNA photoligation has been applied to a method to construct heat-resistant two-dimensional (2D) DNA arrays that can work as scaffolds in bottom-up assembly of functional biomolecules and nano-electronic components. DNA double-crossover AB-staggered (DXAB) tiles were covalently connected by enzyme-free template-directed photoligation, which enables a specific ligation reaction in an extremely tight space and under buffer conditions where no enzymes work efficiently. DNA nanostructures created by self-assembly of the DXAB tiles before and after photoligation have been visualized by high-resolution, tapping mode atomic force microscopy in buffer. The improvement of the heat tolerance of 2D DNA arrays was confirmed by heating and visualizing the DNA nanostructures. The heat-resistant DNA arrays may expand the potential of DNA as functional materials in biotechnology and nanotechnology

N-Oleoyl Sarcosine as an Engine Oil Friction Modifier, Part 2: Elucidation of Friction-Reducing Mechanism at Room Temperature Focusing on Contribution of NOS in NOS+ZDDP Mixture

The tribological properties of a mixture of a commercial organic friction modifier, N-oleoyl sarcosine (NOS), and a commercial anti-wear additive, zinc dialkyldithiophosphate (ZDDP), were investigated. The results suggest a synergistic effect between these two additives, resulting in a mixture that exhibited the lowest and most stable friction coefficient as well as the smallest wear area. X-ray photoelectron spectroscopy was performed to investigate the chemical composition of the tribo-films formed using this mixture. The results suggest that the tribo-films lacked S as well as PO4³⁻ species. They also suggest that ZDDP mitigates degradation of the NOS, and improve the tribo-film durability thus improving anti-wear/friction-reducing performance. These results elucidate the synergistic friction-reducing tribological mechanism of the NOS+ZDDP mixture

N-Oleoyl Sarcosine as an Engine Oil Friction Modifier, Part 1: Tribological Performance of NOS+ZDDP Mixture at 100°C

The friction coefficient when a Fe surface was lubricated with an additive mixture of N-Oleoyl sarcosine (NOS), a commercial organic friction modifier, and zinc dialkyldithiophosphate (ZDDP) was measured at 100°C using a ball-on-disk tribometer under boundary lubrication conditions. The sliding surface was observed with a 3D laser microscope to investigate the tribo-film morphology and to evaluate the anti-wear performance. The findings indicate that this additive mixture enhanced tribological lubrication behavior in terms of friction-reducing and anti-wear properties under extended sliding cycle conditions. Scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDX) studies were conducted to analyze the elemental composition of sliding surfaces after tribo-tests and to estimate the friction reduction mechanism of the additive mixture. The EDX results revealed a noticeable decrease in S, suggesting that the NOS suppresses ZDDP decomposition and reduces the adsorption of the decomposition products

Automatic Tracking of Region of Interest in Sonograms Using Respiratory Information

In heavy ion radiation therapy for cancer, tracking the region of interest (ROI) is important in order to monitor the position of the treatment target, which varies with respect to respiration, during therapy. We previously proposed a method to compute the optical flow, which is a 2-D velocity field, and the locus of the ROI in the internal organs using the optical flow and its reliability. In the present work, this locus is assumed to be prior knowledge and an on-line tracking method of the ROI is proposed. In this method, the ROI position is predicted using the estimated locus, and the template matching technique usingthe respiratory information is applied. The locus is then updated using the template matching result obtained via the Kalman filter. The effectiveness and reliability of this method are confirmed through real image experiments