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An innovative image processing methodology is proposed to draw the magnetization curves of electrical steels. Our methodology enables to draw the continuous magnetization curve from a series of the distinct scanning electron microscope (SEM) images of magnetic domains. Our image processing methodology has two distinguished features. One is that the contrast of a domain image is regarded as an average of flux density. Another one is that domain motion observed in several domain images is represented by the image Helmholtz equation. Its solution generates any magnetized states of the magnetic domains. Moreover, computing averaged contrast of each image gives value of flux density on a magnetization curve. In this paper, we apply our methodology to the domain images of a grain-oriented electrical steel. This paper demonstrates the macroscopic- as well as microscopic-magnetization curves reflecting on their physical conditions. Index Terms--Grain-oriented electrical steel, image processing, magnetic domains, magnetization curve, scanning electron microscope.

The T2 phase in the Mo–Si–B system has great potential for ultra-high temperature structural applications. We examined creep of the single crystalline and polycrystalline T2 phase. The steady-state creep rate of the [021] oriented specimens is as low as 3.1×10-8 s-1 at 1500 °C and 432 MPa. The minimum creep rates at 1500 °C of the [001] oriented and polycrystalline specimens are 6.9×10-8 s-1 at 600 MPa and 3.0×10-8 s-1 at 300 MPa, respectively. The activation energy for creep was found to be ∼740 and ∼400 kJ mol-1 for [021] and [001] oriented specimens, respectively. Stress exponent for creep was found to be 6.8, 4.3 and 4.6 for [021] and [001] oriented and polycrystalline specimens, respectively. Creep resistance of the single crystalline and polycrystalline T2 specimens is much better than that of MoSi2 and Si3N4 base structural ceramics. [Copyright &y& Elsevier]

Human cytochrome P450 3A4 (CYP3A4) is a drug-metabolizing enzyme that is abundantly expressed in the liver and intestine. It is an important issue whether compounds of interest affect the expression of CYP3A4 because more than 30% of commercially available drugs are metabolized by CYP3A4. In this study, we examined the effects of cholesterol and cholic acid on the expression level and activity of CYP3A4 in hCYP3A mice that have a human CYP3A gene cluster and show human-like regulation of the coding genes. A normal diet (ND, CE-2), CE-2 with 1% cholesterol and 0.5% cholic acid (HCD) or CE-2 with 0.5% cholic acid was given to the mice. The plasma concentrations of cholesterol, cholic acid and its metabolites in HCD mice were higher than those in ND mice. In this condition, the expression levels of hepatic CYP3A4 and the hydroxylation activities of triazolam, a typical CYP3A4 substrate, in liver microsomes of HCD mice were higher than those in liver microsomes of ND mice. Furthermore, plasma concentrations of triazolam in HCD mice were lower than those in ND mice. In conclusion, our study suggested that hepatic CYP3A4 expression and activity are influenced by the combination of cholesterol and cholic acid in vivo., (© 2024 The Authors. Pharmacology Research & Perspectives published by British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics and John Wiley & Sons Ltd.)

Progesterone (P) and 17β-estradiol (Eβ) form the well-known hormone pair that regulates sperm capacitation. Here, we examined the regulatory effects of P and Eβ on sperm hyperactivation in mice and evaluated the in vitro fertilization (IVF) success. Although P enhanced hyperactivation, Eβ dose-dependently suppressed the P-enhanced hyperactivation. Moreover, P increased IVF success, whereas Eβ suppressed the P-induced increase in IVF success in a dose-dependent manner. Thus, P and Eβ competitively regulate hyperactivation and IVF success in mice. Since P and Eβ concentrations generally change during the estrous cycle, sperm are speculated to capacitate in response to the oviductal environment and fertilize the oocyte.

The accurate diagnosis of vascular anomalies (VAs) is considered a challenging endeavor. Misdiagnosis of VAs can lead clinicians in the wrong direction, such as the performance of an unnecessary biopsy or inappropriate surgical procedures, which can potentially lead to unforeseen consequences and increase the risk of patient injury. The purpose of the present study was to develop an approach for the diagnosis of VAs of the oral and maxillofacial region based on computed tomography (CT), magnetic resonance imaging (MRI) and dynamic contrast-enhanced MRI (DCE-MRI). In the present study, the CT and MR images of 87 VAs were examined, and the following imaging features were evaluated: Detectability of the lesion, the periphery of the lesion, the inner nature of the lesion, the density of the lesion on CT, the signal intensity of the lesion on MRI, the detectability of phleboliths and the shape of the lesion. A total of 29 lesions were further evaluated using the contrast index (CI) curves created from the DCE-MRI images. A diagnostic diagram, which is based on the imaging features of VAs and CI curve patterns, was subsequently extrapolated. The results obtained demonstrated that the VAs were detected more readily by MRI compared with CT, whereas the detectability of phleboliths was superior when using CT compared with MRI. VAs showed a propensity for homogeneous isodensity on CT, whereas, by contrast, they exhibited a propensity for heterogeneous hyperdensity on CE-CT. VAs also showed a propensity for homogeneous intermediate signal intensity when performing T1-weighted imaging (T1WI), heterogeneous high signal intensity when performing short tau inversion recovery MRI, and heterogeneous high signal intensity when performing fat-saturated CE-T1WI. The CI curves of VAs were found to exhibit a specific pattern: Of the 29 CI curves, 23 (79.3%) showed early weak enhancement, followed by a plateau leading up to 400-600 sec. An imaging-based diagnostic diagram was ultimately formulated. This diagram can act as an aid for radiologists when they are expecting to find a VA, and hopefully serve the purpose of simplifying the diagnostic process. Taken together, the findings of the present study indicated that DCE-MRI may be considered a useful tool for the diagnosis of VAs., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Al-Hammad et al.)

Aims: The purpose of the present study is to analyze the fluid-attenuated inversion recovery (FLAIR) signal intensity of the retrodiscal tissue in a painful temporomandibular joint (TMJ), and to develop a diagnostic system based on FLAIR data., Methodology: The study was based on 33 joints of 17 patients referred for MR imaging of the TMJ. Regions of interest were placed over retrodiscal tissue and gray matter (GM) on FLAIR images. Using signal intensities of GM as reference points, signal intensity ratios (SIR) of retrodiscal tissue were calculated. SIRs in painful TMJ were compared with those in painless TMJ. Wilcoxon's Rank Sum Test was used to analyze the difference in SIRs between the painful and painless groups (P<0·05)., Results: The SIRs of retrodiscal tissue were significantly higher in painful joints than in painless joints., Conclusion: FLAIR sequences provide a high signal in patients having painful TMJ, and it suggests that retrodiscal tissue in painful TMJ contains elements such as protein.

A 42-year-old woman with biopsy-proven chronic hepatitis B, who had been treated with human leukocyte-derived interferon-alpha (huLe-IFN alpha) therapy for two months was found to have liver tumors on routine abdominal ultrasonography examination. She underwent laparotomy, and partial hepatectomy was performed under the clinical diagnosis of hepatocellular carcinoma. The lesions were diagnosed histologically as pseudolymphoma based on the massive infiltration of small mature lymphocytes and the presence of hyperplastic lymph follicles with germinal centers. Immunohistochemistry revealed polyclonal origin of the involved lymphocytes. The possible association between IFN alpha treatment and chronic hepatitis B with the development of pseudolymphoma is discussed.