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This is a post-peer-review, pre-copyedit version of an article published in Journal of Medical Ultrasonics. The final authenticated version is available online at: https://doi.org/10.1007/s10396-020-01045-3., Purpose: The peak systolic strain decreases due to afterload augmentation. However, its deterioration (i.e., afterload sensitivity) may be different within the left ventricular (LV) segments. We investigated how afterload influences regional strain and whether there is regional heterogeneity of afterload sensitivity. Methods: Afterload was increased by aortic banding in 20 open-chest dogs. Short-axis images were acquired at baseline and during banding. Circumferential strain was analyzed in six segments, and the absolute decrease in the peak systolic strain during banding (Δε) was calculated for each segment. To assess the effect of the compensatory preload recruitment during banding, the endocardial lengths of the septum and free wall were measured at end-diastole, and the rate of increase due to banding was calculated. Results: LV systolic pressure was significantly increased during banding (100 ± 14 vs. 143 ± 18mmHg, P < 0.001). The peak systolic strain in all segments was significantly decreased during banding. Δɛ in the anterior segment, which is a part of the free wall, was significantly lower than that in the inferoseptal segment (2.6 ± 4.7 vs. 6.5 ± 3.5%, P = 0.035). The rate of increase in endocardial length in the free wall was significantly larger than that in the septum (15.6 ± 10.4 vs. 8.1 ± 7.4%, P = 0.014). Conclusion: The decrease in septal strain during afterload augmentation was larger than that in free wall strain, indicating that there was regional heterogeneity of afterload sensitivity in circumferential strain. The larger compensatory preload recruitment in the free wall than in the septum is implicated as a cause of the heterogeneity.

Using ultrafast pump-probe spectroscopy combined with a time-partitioning Fourier transform, we demonstrate transient mechanical distortion of Single-wall carbon nanotubes by photoexcitation assisted by protein adsorption.

In order to obtain road information, we propose a road information acquisition method using scanning range finder by detecting 2D reflector code on roadside. The scanning range finder on vehicle scans the 2D reflector code on roadside. Through some experiments, we show that the proposed method is able to obtain road information by detecting 2D reflector code on roadside.

A non-destructive method for discriminating between different types of paper has been proposed, using image analysis, Fourier transformation, and cross-correlation matching. A fast Fourier transform (FFT) is used to extract the periodicity in the structure of paper that results from the manufacturing processes. The light-transmission images of the paper to be Fourier transformed are obtained from a flatbed image scanner. The similarity between the power spectrum of the FFT of the sample and that of a reference is quantified using a cross-correlation matching method. An advantage of using frequency analysis is that periodicity can be detected even if the sample is damaged or is printed on. The technique works on samples as small as 2 cm 2 .