Theoretical estimation of dielectric loss of oxide glasses using nonequilibrium molecular dynamics simulations

To theoretically explore amorphous materials with a sufficiently low dielectric loss, which are essential for next-generation communication devices, the applicability of a nonequilibrium molecular dynamics simulation employing an external alternating electric field was examined using alkaline silicate glass models. In this method, the dielectric loss is directly evaluated as the phase shift of the dipole moment from the applied electric field. This method enabled us to evaluate the dielectric loss in a wide frequency range from 1 GHz to 10 THz. It was observed that the dielectric loss reaches its maximum at a few THz. The simulation method was found to qualitatively reproduce the effects of alkaline content and alkaline type on the dielectric loss. Furthermore, it reasonably reproduced the effect of mixed alkalines on the dielectric loss, which was observed in our experiments on sodium and/or potassium silicate glasses. Alkaline mixing was thus found to reduce the dielectric loss.     

Molecular Targeted Therapy for the Bone Loss Secondary to Pyogenic Spondylodiscitis Using Medications for Osteoporosis: A Literature Review

Pyogenic spondylodiscitis can cause severe osteolytic and destructive lesions in the spine. Elderly or immunocompromised individuals are particularly susceptible to infectious diseases; specifically, infections in the spine can impair the ability of the spine to support the trunk, causing patients to be bedridden, which can also severely affect the physical condition of patients. Although treatments for osteoporosis have been well studied, treatments for bone loss secondary to infection remain to be elucidated because they have pathological manifestations that are similar to but distinct from those of osteoporosis. Recently, we encountered a patient with severely osteolytic pyogenic spondylodiscitis who was treated with romosozumab and exhibited enhanced bone formation. Romosozumab stimulated canonical Wnt/β-catenin signaling, causing robust bone formation and the inhibition of bone resorption, which exceeded the bone loss secondary to infection. Bone loss due to infections involves the suppression of osteoblastogenesis by osteoblast apoptosis, which is induced by the nuclear factor-κB and mitogen-activated protein kinase pathways, and osteoclastogenesis with the receptor activator of the nuclear factor-κB ligand-receptor combination and subsequent activation of the nuclear factor of activated T cells cytoplasmic 1 and c-Fos. In this study, we review and discuss the molecular mechanisms of bone loss secondary to infection and analyze the efficacy of the medications for osteoporosis, focusing on romosozumab, teriparatide, denosumab, and bisphosphonates, in treating this pathological condition.     

Volumetric Change and Surface Properties of Temperature-Sensitive Polyvinylalcohol (PVA) Hydrogel

Polyvinylalcohol (PVA) polymer gel is a temperature sensitive polymeric gel, with a critical transition temperature (with H₂O) of 310 K. At higher than 310 K, this temperature sensitive polymer gel shrinks because of discharging water, whereas at lower temperatures, the gel swelled because of absorbing water. The reversibility of the gel's volume change was confirmed by temperature swing. The adsorption behavior of an organic compound onto the PVA polymer gel in water was tested at various temperatures. The amount of adsorbed organic compound increased remarkably at temperatures higher than about 310 K. Then, it was confirmed that the organic compound in PVA polymer gel could be reversibly adsorbed and desorbed by a temperature change between 293 and 323 K. The mechanism of adsorption of the organic compound onto the PVA polymer gel could be explained by hydration and dehydration of polymer gel.     

日本应用预应力混凝土预制件建造公路防灾构筑物的情况

本文介绍了日本公路工程利用预应力混凝土预制件修建防灾构筑物的情况。防灾构筑物可分为:防雪灾和防落石、塌方两种。也可分为预防工程和防护工程构筑物,如防风雪掩道、防雪崩栅栏、防雪崩安全隧道、防雪崩栏杆、防落石、防塌方安全隧道和防落石栏杆,以及用FRP的吊栅栏、用泡沫苯乙烯的悬臂梁防落石栏杆等。     

Unperturbed dimension of poly(4-acetoxystyrene) measured in good and theta solvents

In order to obtain the additional data concerning the unperturbed dimension of poly-4-substituted styrene, light scattering measurements are performed on the twenty-two fractions with molecular weight of (0.91–352)·10⁴ of poly(4-acetoxystyrene) in dioxan at 25°C, from which the molecular weight obtained was found easily to be evaluated with the gel permeation chromatography using THF. Phase separation experiments for this polymer indicate that the theta state is attained in isopropyl acetate at 19.7°C and butyl acetate at 26.8°C. By making viscosity measurements at that state, the value of K_Θ is directly evaluated as 5.4·10^?4 dl g^?1. The limiting viscosity number is also obtained in good solvents, THF and dioxan, at 25°C and constants of the Mark-Houwink-Sakurada equation in each solvent are determined. Further, approximately the same K_Θ as above is obtained from these data with the Stockmayer-Fixman plot. The calculated value of steric factor, 2.37, on this polymer may be plausible, compared with those of polyvinylaromatic derivatives.     

Infrequent mutation of the H-cadherin gene on chromosome 16q24 in human breast cancers

To investigate the molecular basis of altered expression of the H-cadherin gene, we used polymerase chain reaction-single strand conformation polymorphism and DNA sequencing to examine the H-cadherin gene in 48 primary breast cancers in which loss of the long arm of chromosome 16 had been detected. We identified no mutations other than somatic 5-bp deletion within the coding region in a single tumor. The very low frequency of mutation found in these experiments suggests that H-cadherin is usually not a primary target for carcinogenesis in human breast cancers, and that reduction of its expression is likely to be a consequence of some other genetic event(s).     

Clinico-laboratory characteristics and treatment of patients with trichinosis

The severity of clinical features of trichinosis and cardiac involvement incidence were examined in the study. The values of eosinophiles, serum enzymes and serologic response to T. spiralis were determined in relation to the disease severity. Twenty-nine patients, of mean age from 24 to 29 years treated in the Clinic in the period from January to April 1995 were presented-7 with severe form of trichinosis, 10 with moderately severe and 12 with light. The fever was noticed in 93.1% of patients, gastrointestinal disorders in 65.5%, myalgias in 96.6%, facial edema in 79.3%, cardiac disorders in 31% and rash in 20.7%. Positive IIF test result was found in 100% of patients with severe clinical features, and only in 58.3% of patients with light clinical features. The patients were treated with mebendazole in the dose of 25 mg/kg BM a day during 14 days. It was concluded that severe trichinosis forms were frequently followed by myocardial damage, that severe forms responded faster and better serologically to trichinella and those patients should be treated with high mebendazole doses.     

An automatic torque ripple compensation system for direct drive motors

A serious problem in motion control is the occurrence of torque ripple. Since a direct drive (DD) motor with a magnet rotor uses a rare-earth magnet, the torque ripple is more serious than that of conventional servomotors. This paper presents an auto-compensation of torque ripple using a software-implemented torque observer. The frequency and amplitude of torque ripple can be obtained in the controller by using the estimated torque from an observer, and the autonomous generation of a compensating current component for a torque ripple is possible. The proposed algorithm has been verified by experiments.     

Three-dimensional display of the bronchi using helical CT

The purpose of this study was to evaluate the clinical usefulness of three-dimensional (3D) images of the bronchi obtained using helical CT. Thirteen patients with lung cancer, one with tracheal diverticulum, and one with bronchial amyloidosis were examined. The CT scanner employed was the Toshiba Xforce. The helical CT scan cycle consisted of 20 continuous rotations, each requiring 1.5 sec, for a total scanning time of 30 sec. Scans were obtained using a 5-mm X-ray beam width, a 5-mm/1.5 sec couchtop sliding speed, and a 2-mm reconstruction interval. 3D images were reconstructed using a CEMAX VIPstation. The optimal lower and upper threshold CT values for 3D images of the bronchi were -650 and -100 HU, respectively, and 3D images clearly depicted endobronchial lesions. Cartilage crescents were also demonstrated, but longitudinal and circular mucosal folds could not be visualized. In conclusion, 3D images of the bronchi acquired using helical CT were useful in evaluating endobronchial lesions.