Summary Objective The management of Rathke's cleft cyst (RCC), particularly in patients with no symptoms or with only minor endocrinopathies, has not yet been established. We retrospectively analysed patients with RCC to elucidate correlations between the clinical manifestations, magnetic resonance imaging (MRI) findings, histology and therapeutic outcomes. Methods We retrospectively studied 37 patients with RCC, who underwent computed tomography (CT), MRI and endocrinological examinations, of whom 27 patients underwent surgical intervention. Results The presence of frontal headaches and anterior pituitary dysfunction was unrelated to the cyst size but was more frequent in patients with high‐ and isointensity cysts on T1‐weighted images (WIs) than those with low‐intensity cysts ( P = 0·0159 and P = 0·0249, respectively). All three patients with posterior pituitary dysfunction had a high‐intensity cyst on T1‐WI ( P = 0·0385), whereas pituitary dysfunction was not observed in patients with a low‐intensity cyst on T1‐WI. In contrast to the excellent therapeutic outcomes with regard to visual disturbance and hyperprolactinaemia, recovery of pituitary dysfunction was rare; only three of nine patients with hypopituitarism showed improvement. Among six patients with histologically recognized intense chronic inflammation in the cyst wall, five patients had an RCC of T1 high intensity ( P = 0·0161), two patients had distinct rim enhancement on MRI ( P = 0·0060), all patients had frontal headaches ( P = 0·0130), and four patients had associated hypopituitarism ( P = 0·0243), none of which improved after surgical intervention. Conclusion RCCs of high‐ and isointensity on T1‐weighted images, which contain mucous material within the cyst, may be associated with chronic inflammation that can potentially cause irreversible endocrine dysfunction. In asymptomatic patients with RCCs of these MR intensities, close follow‐up with precise endocrinological evaluation and gadolinium‐enhanced MRI is necessary to avoid occult progression of the inflammation.
We report here the autopsy findings in a 51-year-old man who had been admitted with Henoch-Schönlein purpura (HSP) accompanied by rapidly progressive glomerulonephritis and massive intraperitoneal hemorrhage, leading to death. While the intraperitoneal hemorrhage was the primary cause of death, the patient may have suffered widespread intraperitoneal vasculitis due to HSP, or hemorrhagic pancreatitis due to the concurrent administration of a steroid and furosemide. We emphasize the acute hemorrhagic pancreatitis is a possible complication in patients with generalized vasculitis, including HSP and collagen disease, during the concurrent administration of steroids and other agents.
Optical fiber sensor systems have been recently used for ,health monitoring of fiber reinforced plastic (FRP) composite laminate structures. However, the diameter of optical fibers for optical communication is normally 125 μm, which is similar to the thickness of one ply in FRP composite laminates. In order to embed optical fibers within one ply of FRP without introducing any defects in laminates, small- diameter optical fibers are necessary. The present paper describes development of small-diameter optical fiber sensors for damage detection in composite laminates. The coating diameter of the prototype small-diameter optical fiber is 52 μm, while the diameters of the cladding and the core are 40 μm and 8.5 μm, respectively. FBG (Fiber Bragg Grating) sensors were also fabricated with these fibers. Gratings were inscribed into the optical fiber by ultra-violet irradiation method. The wavelength shift and the response by strain of FBG itself were measured. The strain response, when small-diameter optical fiber and FBG sensors were embedded in composite laminates, were evaluated for practical application to detect the damage evolution.
Abstract Switched‐capacitor filter (SCF) design methods reported so far fall into one of the following categories: design from the s‐do‐main, in which a filter is synthesized based on a direct approximation to the s‐transfer function; or design from the z‐domain, in which the system is regarded as being discrete and z‐transfer function is used. This paper proposes a new method of SCF synthesis based on an approximate s‐z conversion, starting from a given frequency characteristic. Characteristics of equivalent capacitors and SC integrators are expressed in a variable p(z). The desired characteristic F(s) is then approximated by the least‐square method with a rational function of p, FC(p). An SCF is constructed from FC(p) using the element substitution method in active FC filter networks. Previously proposed methods of synthesis from the s‐domain based on linear approximation or bilinear transformation result in large substitution errors, especially when relatively low sampling frequency is used. The present method minimizes substitution errors and extends signal bandwidth close to its theoretical limit.
Abstract– We found a simple thin shock vein, less than or equal to about 60 μm in width and 1.8 mm in length, in the poikilitic area in the Yamato (Y-) 000047 lherzolitic shergottite. The shock vein occurs only in magnesian Ca-poor clinopyroxene, which may have transformed from orthopyroxene during the pressure increase at the shock event. The shock vein consists of (Mg0.8,Fe0.2)SiO3 pyroxene polymorphs, such as columnar akimotoite, two kinds of pyroxene glasses, dendritic akimotoite, and framboidal pyroxene glass, in the order from the periphery to the center. The compositions and textures suggest that columnar akimotoite in the periphery of the shock vein crystallized from solid-state phase transition of clinopyoroxene during the cooling of the vein, and the remains in the shock vein solidified from shock-produced melt. The glass includes two kinds of massive glass in the vein and framboidal glass in the vein center. The framboidal glass is the most magnesian and may have been vitrified from perovskite crystallized from high-pressure melt produced at high temperature ≥3000 °C and high-pressure 23–40 GPa. Dendritic akimotoites in the vein center metastably crystallized from residual shock melt. The formation sequences of the constituent phases in the shock vein happen in the following order: columnar akimotoites, rim glass, center glass, framboidal glass, and dendritic akimotoites. The increase of the Raman intensity of 660–670 cm−1 in the order of rim glass, center glass, and framboidal glass suggests that the formation of the pyroxene chain proceeds faster in the vein center than in the vein rim due to its slower cooling. The finding of the shock vein consisting merely of high-pressure polymorphs of pyroxene, akimotoite, and framboidal glass (vitrified perovskite) is the first reported among all Martian meteorites.
