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We developed a method for generating continuous sinusoidal displacements of an object to estimate viscoelastic parameters. However, the amplitude of the displacement caused by the ultrasonic excitation force under safe guidelines was small (a few micrometers), and it was difficult to stably measure the displacement. Therefore, to stably measure the amplitude of sinusoidal displacement as small as the order of micrometers, we proposed a novel method using a network analyzer. Ultrasonic waves were irradiated using an ultrasonic transducer to an object vibrating sinusoidally. The S parameter of the first reflected wave received from the surface of the object was measured using a network analyzer. The S parameter and the inverse Fourier transform were formulated theoretically, and the amplitude of the sinusoidal displacement of the object was estimated from the amplitude characteristics of the inverse Fourier-transformed signal. The proposed method was applied to measure sinusoidal displacements on the order of micrometers from 10 to 300 Hz on an object using a water tank experiment. The obtained sinusoidal displacement agreed well with the reference values measured using a laser displacement meter. The proposed method can accurately measure minute sinusoidal displacements that occur on an object. [ABSTRACT FROM AUTHOR]

The article titled "A novel ultrasonic method for measuring minute sinusoidal displacement by network analyzer" was published in the Review of Scientific Instruments. However, the original online version contained typesetting errors, which have since been corrected. The errors included changes in punctuation, spacing, and formatting. AIP Publishing has apologized for the mistakes, and the corrected version is now available online and in the printed version of the journal. The authors of the article are Yuya Komatsu, Shohei Mori, Mototaka Arakawa, and Hiroshi Kanai. [Extracted from the article]

This article presents a Bayesian sparse modeling method to analyze extended x-ray absorption fine structure (EXAFS) data with basis functions built on two-body signals. This method does not require any structural model and allows us to evaluate regression coefficients proportional to the radial distribution functions of the respective elements and their errors and is very effective for analysis of EXAFS with weak absorption intensity and severe signal-to-noise ratios. As an application example, we used it to analyze the EXAFS of an yttrium oxyhydride (YOxHy) epitaxial thin film. These EXAFS data show weak absorption intensity and a severe signal-to-noise ratio due to the small amount of x-ray absorption in the thin film sample. However, this approach revealed that the radial distance ratio of the second neighbor yttrium to the first neighbor oxygen coincides with that of a tetrahedral configuration. This result demonstrates that the interstitial oxygen position is tetrahedral in the YOxHy thin film. [ABSTRACT FROM AUTHOR]

Colonic anisakiasis is rare because most cases of anisakiasis occur in the stomach. An accurate diagnosis is sometimes difficult because of the rarity and symptom nonspecificity. We should consider the possibility of colonic anisakiasis when examining patients who have a history of consuming raw fish. [ABSTRACT FROM AUTHOR]

The use of endoscopic submucosal dissection ( ESD) for duodenal neoplasms has increased in recent years, but delayed perforation and bleeding are also known to frequently occur. We present two cases in which duodenal adenoma was successfully treated with laparoscopic-endoscopic cooperative surgery. ESD was combined with laparoscopic seromuscular sutures. The lesions in both cases were located in the second portion of the duodenum. The patients requested resection of the lesion, and we performed laparoscopic-endoscopic cooperative surgery. After the laparoscopic surgeon mobilized the duodenum, the endoscopic surgeon performed ESD for the duodenal tumor without perforation. The laparoscopic surgeon sutured the duodenal wall in the seromuscular layer to strengthen the ulcer bed after ESD. Histopathological studies confirmed that the surgical margins were tumor-free in both cases. The patients were discharged with no complications. This unique laparoscopic-endoscopic cooperative procedure is a safe and effective method for resecting superficial nonampullary duodenal tumors. [ABSTRACT FROM AUTHOR]