The Additional Magnetic Anisotropy Induced by Magnetic Anneal in Ferromagnetic Face-Centered Cubic Solid Solutions : Part I. Dependence of the Induced Magnetic Anisotropy on the Temperature and Duration of Magnetic Anneal, on the Measuring Temperature, and on the Alloy Composition in Face-Centered Cubic Nickel-Cobalt Alloys

We have studied systematically the character of the induced magnetic anisotropy in face-centered cubic Ni-Co alloys, using a torque magnetometer designed specially for high-temperature measurements. Specimens used are polycrystalline disks of 10.57, 20.78, 30.84, 40.67, 50.17, and 60.20 %Co-Ni alloys and (110) disk single crystal of 12 %Co-Ni alloy. The results and conclusions obtained are as follows : -The magnetic anisotropy energy, E_u, induced by magnetic anneal is uniaxial. Generally, as the duration of magnetic anneal increases, E_u increases nearly exponentially and, as the temperature of magnetic anneal becomes higher, the rate of development of E_u increases but its saturation value decreases. The development of E_u can not be described in terms of single relaxation time and the associated relaxation times become longer as the duration of magnetic anneal increases. The dependence of E_u\u27 on the temperature, Θ, of magnetic anneal and on the measuring temperature, T, can be expressed well by an expression E_u=const. ×{ (I_Θ/I_0)^2/Θ} (I_T/I_0)^2 where I_Θ, I_T, and I_0 are the values of saturation magnetization at Θ(°K), T(°K), and 0°K, respectively, which was derived by Taniguchi and Yamamoto from the so-called directional order theory. The comparison of the measured data on the alloy composition dependence of E_u as corrected for the composition dependence of the Curie temperature with Neel\u27s theoretical formula indicates that the ordering energy of Ni-Co alloys is negative and hence the alloys may be of the precipitation type. In connection with this study, the temperature dependence of the cubic magnetocrystalline anisotropy constants, K_1 and K_2, was measured with 12 %Co-Ni alloy and pure nickel, and it has been found that, as the temperature rises, K_1 of 12 %Co-Ni alloy changes from positive to negative at about 150℃, while K_1 of nickel takes small positive values above 200℃ and that K_2 of 12% Co-Ni alloy is always positive, while K_2 of nickel changes from positive to negative at about 100℃

Ferromagnetic Domain Structure as Affected by the Uniaxial Anisotropy Induced in a 40 Percent Co-Ni Single Crystal

We have found that the domain structure in the annealed state of a 40 percent cobalt-nickel single crystal is very fine and complicated as compared with those of ordinary ferromagnetic crystals but it becomes simpler and larger after quenching from above the Curie temperature. This can be explained as follows : Since the domain structure may in general be fine and complicated at temperatures just below the Curie temperature, domain walls must displace to establish a more stable domain configuration as the temperature lowers. But, this process is suppressed appreciably at relatively low temperatures, because, in solid solution, the ferromagnetic uniaxial anisotropy is induced, in compliance with the domain distribution, by the anisotropic distribution of atoms at high temperatures and the domain wall displacement can take place only by being accompanied by the redistribution of atoms which can not occur at low temperatures. While, in quenching, the specimen crystal is cooled down so rapid that the uniaxial anisotropy and hence the anisotropic distribution of atoms can not be induced, and thus the quenched specimen crystal behaves just as ordinary ferromagnetic crystals. It is shown that these findings together with the results of considerations reported previously lead us to the conclusion that the perminvar-type magnetic properties are due to the stabilization of domain walls by the induced uniaxial anisotropy in f. c. c. solid solutions with cubic anisotropy constants of any sign and b. c. c. solid solutions with negative cubic anisotropy constants

Intestinal Fibroblast/Myofibroblast TRP Channels in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is characterized by the repeated cycles of inflammation and healing of the gut, which ultimately progress into intestinal fibrosis. Colonic fibroblast/myofibroblast’s functions such as transformation, proliferation, invasion, migration, stress fiber formation, collagen synthesis, and cytokine/chemokine secretion are well estimated. However, the detailed mechanism can rarely be found so far. Thus, we focused on transient receptor potential (TRP) protein super family activated by various physical/chemical stimulations based on the above-described recognitions and also conducted the following examinations for the potential roles in Ca2+ signal transduction in fibroblast/myofibroblasts cells, which play an important role in intestinal inflammation and tissue remodeling. This chapter not only facilitates the understanding about the new role of intestinal fibroblast/myofibroblasts TRP channel for regulating inflammation, fibrotic processes but also suggests a novel molecular target of IBD treatment in future

Impact of the omicron phase on a highly advanced medical facility in Japan

BackgroundEight waves of the coronavirus disease 2019 (COVID-19) epidemic have been observed in Japan. This retrospective study was conducted to clarify the clinical characteristics of pediatric COVID-19 patients.MethodsWe studied 121 patients admitted to the Jichi Children's Medical Center Tochigi between April 2020 and March 2023. Incidence of pediatric COVID-19 in Tochigi Prefecture was used to examine hospitalization and severe illness rates.ResultsThe mean age of the patients was 3 years and 8 months. One hundred and eleven patients (91.7%) were hospitalized after January 2022 (after the 6th wave), when the Omicron strain became endemic in Japan. Convulsions occurred in 30 patients (24.8%), all of whom were admitted after the 6th wave. Twenty-three of the 30 patients had no underlying disease. Eleven patients (9.1%) were diagnosed with acute encephalopathy. One patient died due to hemorrhagic shock and encephalopathy syndrome and two had sequelae after the 6th wave. The patient who died due to encephalopathy had hypercytokinemia. In the Tochigi Prefecture, the number of pediatric COVID-19 patients increased after the 6th wave, but the hospitalization rate declined. The rate of severe illness did not change before the end of 5th and after the 6th wave.ConclusionAlthough the rate of severe illness in patients with pediatric COVID-19 did not increase after the 6th wave, some patients had complicated critical illnesses. Systemic inflammatory reaction was considered to have been associated with the severe encephalopathy

The Additional Magnetic Anisotropy Induced by Magnetic Anneal in Ferromagnetic Face-Centered Cubic Solid Solutions : Part. II. Crystal Orientation Dependence of the Induced Magnetic Anisotropy in Face-Centered Cubic Nickel-Cobalt and Nickel-Iron Alloys

The induced uniaxial ferromagnetic anisotropy as a function of the crystal orientation has been measured, using a torque magnetometer, with magnetically annealed (110) disc single crystals of 12 and 20 %Co-Ni and 17 and 46 %Fe-Ni alloys. It has been found that the crystal orientation dependence of the induced uniaxial ferromagnetic anisotropy energy, E_u, is expressed by the formula E_u=-K(Σ_iα_i^2β_i^2+kΣ_j>iα_iα_jβ_iβ_j), where K is a positive constant, k a numerical factor, and α_i\u27s and β_i\u27s (i=1, 2, 3) the direction cosines of magnetization vectors during the torque measurement and during magnetic annealing, respectively. The factor k is 2～3 except for Ni-Fe alloys nearby Ni_3Fe, being smaller than 4 as expected from the directional order theory for face-centered cubic alloys. This difference may partly be due to the fact that the contribution from the second neighbor atoms is neglected in the theory, and rather large values of k for Ni-Fe alloys nearby Ni_3Fe may be due to the presence of superlattice

ANGIOGRAPHIC DEMONSTRATION OF CEREBRAL REVASCULARIZATION AFTER ENCEPHALO-DURO-ARTERIO-SYNANGIOSIS (EDAS) PERFORMED ON PEDIATRIC MOYAMOYA PATIENTS

For the treatment of the moyamoya disease, we developed a surgical procedure of Encephalo­duro-aterio-synangiosis (EDAS), which was conducted in 15 cases on 23 sides. As a result we obtained improvement in cerebral vascularization as well as in neurological and electroencephalo­graphic findings in all cases. This report describes an introduction of the procedure and a review of the postoperative cerebral angiograms. Cerebral revascularization by EDAS proceeded on the following steps, and it was confirmed that efficient cerebral revascularization could be obtained 6 months after the operation in almost all cases following the steps: 1) dilatation and increase of dural artery, 2) dalatation of donor scalp artery, 3) cerebral revascularization with the development of visible fine spontaneous anastomoses between the donor scalp artery and the cerebral arteries and 4) further dilatation of the donor scalp artery and retraction of the abnormal rete vasculosum at the base of the brain

Activation of Myofibroblast TRPA1 by Steroids and Pirfenidone Ameliorates Fibrosis in Experimental Crohn's Disease

The transient receptor potential ankyrin 1 (TRPA1) channel is highly expressed in the intestinal lamina propria, but its contribution to gut physiology/pathophysiology is unclear. Here, we evaluated the function of myofibroblast TRPA1 channels in intestinal remodeling. Methods: An intestinal myofibroblast cell line (InMyoFibs) was stimulated by transforming growth factor-β1 to induce in vitro fibrosis. Trpa1 knockout mice were generated using the Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) system. A murine chronic colitis model was established by weekly intrarectal trinitrobenzene sulfonic acid (TNBS) administration. Samples from the intestines of Crohn’s disease (CD) patients were used for pathologic staining and quantitative analyses. Results: In InMyoFibs, TRPA1 showed the highest expression among TRP family members. In TNBS chronic colitis model mice, the extents of inflammation and fibrotic changes were more prominent in TRPA1-/- knockout than in wild-type mice. One-week enema administration of prednisolone suppressed fibrotic lesions in wild-type mice, but not in TRPA1 knockout mice. Steroids and pirfenidone induced Ca2+ influx in InMyoFibs, which was antagonized by the selective TRPA1 channel blocker HC-030031. Steroids and pirfenidone counteracted transforming growth factor-β1–induced expression of heat shock protein 47, type 1 collagen, and α-smooth muscle actin, and reduced Smad-2 phosphorylation and myocardin expression in InMyoFibs. In stenotic intestinal regions of CD patients, TRPA1 expression was increased significantly. TRPA1/heat shock protein 47 double-positive cells accumulated in the stenotic intestinal regions of both CD patients and TNBS-treated mice. Conclusions: TRPA1, in addition to its anti-inflammatory actions, may protect against intestinal fibrosis, thus being a novel therapeutic target for highly incurable inflammatory/fibrotic disorders