Acceptable distortion and magnification of images on reflective surfaces in an augmented reality system

In this paper, we investigated the consistency of visual perception for the change of reflection images in an augmented reality setting. Reflection images with distortion and magnification were generated by changing the capture position of the environment map. Observers evaluated the distortion and magnification in reflection images where the reflected objects were arranged symmetrically or asymmetrically. Our results confirmed that the observers’ visual perception was more sensitive to changes in distortion than in magnification in the reflection images. Moreover, the asymmetrical arrangement of reflected objects effectively expands the acceptable range of distortion compared with the symmetrical arrangement.     

Rapid microRNA detection using power-free microfluidic chip: coaxial stacking effect enhances the sandwich hybridization

We present a new method for rapid microRNA detection with a small volume of sample using the power-free microfluidic device driven by degassed PDMS. Target microRNA was detected by sandwich hybridization taking advantage of the coaxial stacking effect. This method allows us to detect miR-21 in 20 min with a 0.5 μL sample volume at a limit of detection of 0.62 nM. Since microRNAs can act as cancer markers, this method might substantially contribute to future point-of-care cancer diagnosis.     

Total synthesis of an antitubercular lactone antibiotic, (+)-tubelactomicin A

(+)-Tubelactomicin A (1), an antitubercular lactone, has been synthesized from (S)-citronellol (2) and 2-deoxy-l-ribonolactone (18) through intramolecular Diels-Alder reaction, Suzuki-Miyaura coupling, and Shiina macrolactonization.     

Affinity capillary electrophoresis of DNA for detection of single-nucleotide polymorphisms and point mutations. Comprehensive study for optimization of the weak affinity

A single-stranded DNA and its point mutant can be separated with affinity capillary electrophoresis (ACE) in which an appropriate ligand DNA is used as a pseudo-stationary affinity phase. In this paper, we systematically examine the effects of ligand sequence, capillary temperature, and cation concentration on the ACE separation quality, which is quantitatively evaluated in terms of resolution and peak height. For fine tuning of the affinity, control of MgCl(2) concentration and insertion of a spacer sequence into the ligand DNA are more effective than control of the capillary temperature. For design of the ligand DNA, a simple strategy is proposed, based on the prediction of melting temperature. This strategy was tested with eleven different sample sequences. All of them were separated under the same conditions (250 microM MgCl(2) and 25 degrees C), and nine cases of them had satisfactory separation qualities.     

Evaluation of probe size in STEM imaging at 30 and 60 kV

In order to estimate the probe size on the specimen surface in a newly developed low-acceleration-voltage (30–60 kV) atomic-resolution scanning transmission electron microscopy (STEM), we compared the intensity profiles of experimentally obtained annular dark field (ADF)-STEM images of Si–Si dumbbells and those of images simulated using a multislice method which takes chromatic aberration into account. However, the simulated ADF images at 30 and 60 kV were found not to match the corresponding experimental images. Subsequently, the simulated images were convolved with probe functions (normal distributions) of different widths until a good match was obtained between the images. This allowed the probe shapes corresponding to the experimental conditions to be determined. ADF-STEM images with chromatic aberration could then be calculated by an incoherent superposition of these probe functions over a range of energies. The full widths at half maximum for the probe functions were estimated to be 99.2 pm for 30 kV and 92.8 pm for 60 kV. The D59 diameters were calculated to be 154.0 pm for 30 kV and 127.8 pm for 60 kV. This means that the 30-kV probe has a larger tail than the 60-kV probe.     

Effect of heat treatments on the luminescence properties of Zn2SiO4:Mn2+ phosphors prepared by glycothermal methods

Manganese-doped Zn₂SiO₄ phosphors with different crystal structures and morphologies were synthesized by glycothermal reactions of zinc acetate dihydrate and manganese(II) acetate tetrahydrate with tetraethyl orthosilicate in various glycols at 315 °C. The reactions in 1,3-propanediol and 1,4-butanediol yielded α-Zn₂SiO₄:Mn²⁺, whereas the reactions in ethylene glycol and 1,5-pentanediol yielded β-Zn₂SiO₄:Mn²⁺ and ZnO, respectively. The samples obtained in 1,4-butanediol and 1,3-propanediol emitted green light (522 nm), and the sample prepared in 1,4-butanediol showed a higher emission intensity. The photoluminescence intensity of the Zn_1.96Mn_0.04SiO₄ phosphor prepared by a glycothermal reaction in 1,4-butanediol and subsequently calcined at 1100 °C was twice as high as that of the sample synthesized by a conventional solid-state reaction. The high emission efficiency was obtained because the highly homogeneous distribution of Mn²⁺ in the α-Zn₂SiO₄ host synthesized by the glycothermal reaction was maintained during calcination treatment in air.