Highly reliable 200 mW AlGaAs laser diode with fundamental transverse mode

A highly reliable 200 mW AlGaAs laser diode with a fundamental transverse mode has been developed, by optimising its structure with a 0.8 mu m thick p-cladding layer, a 1200 mu m long cavity length, and a front facet coating with a low reflectivity of 2%. The maximum output power was 500 mW, and stable fundamental transverse mode operation was obtained up to 350 mW. Stable operation under 200 mW and 50 degrees C was confirmed for more than 1200 h. Optical feedback noise was below 3*10/sup -14/ Hz/sup -1/.<>     

High‐pixel‐rate grating‐light‐valve laser projector

Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed.     

Rapid somatic growth after birth in children with neuroblastoma: A survey of 1718 patients with childhood cancer in Kyushu-Okinawa district

OBJECTIVE: To evaluate the association of somatic growth from birth through diagnosis with the development of childhood cancer. METHODS: The weights and heights of 1718 children with cancers were determined and converted into standard deviation (SD) scores, both at birth and at diagnosis, by using the means and SD values of the general population. RESULTS: Among patients with neuroblastoma and acute lymphoblastic leukemia, the percentages of children with body weight and height over mean + 2 SDs were significantly higher at diagnosis than the expected value in the general population. The percentage of children with neuroblastoma and body weight over mean + 2 SD increased significantly from birth through diagnosis (P =.04). Although the medians of weight SD scores decreased from birth through diagnosis in patients with representative cancers except for neuroblastoma, the value significantly increased in patients with neuroblastoma diagnosed before 1 year of age (P =.03), especially in those whose cancer was detected by mass screening at 6 months of age (P <.01). CONCLUSIONS: Rapid somatic growth from birth through diagnosis in patients with neuroblastoma diagnosed before 1 year of age suggests a possible involvement of certain growth factors in these patients.     

Increased urinary excretion of 3-oxo-delta4 bile acids in Japanese patients with idiopathic neonatal cholestasis

This report examines the reliability of nighttime blood pressure dipping. Twenty-one individuals were studied twice with ambulatory blood pressure monitoring. On one occasion they were studied as outpatients, and on the other as inpatients on a clinical research ward. Blood pressure monitoring revealed the expected dip in blood pressure at nighttime. However, there was little test-retest reliability across the two settings. The test-retest correlations for the dip in blood pressure across the two settings were nonsignificant for systolic, diastolic, and mean arterial blood pressure. Caution is advised before diagnosing dipping or nondipping on the basis of one 24-h ambulatory blood pressure recording.     

Small advanced colorectal adenocarcinomas: report on three cases

Small advanced cancers (less than 10 mm in size) have rarely been described in the literature, mainly due to their difficult endoscopic diagnosis. A total of 5120 colonoscopic examinations were performed at the National Cancer Center Hospital East; three cases (0.05%) of small advanced cancer were found. The indigo carmine dye spraying technique with magnifying endoscopy was used for diagnosis. All cases were flat and depressed lesions (8, 9 and 9 mm in size respectively) with V type pit pattern at the magnifying observation. Histology showed three cancers with invasion to the proper muscle layer and two cases of lymph node metastasis. K-ras point mutation was negative in all cases, while p53 stained in two out of the three cases (one diffuse and one focal). It is concluded that small advanced colorectal adenocarcinomas are a reality. Our data on their macroscopic appearance and histology confirm their high malignant potential.     

Pathology of chronic hepatitis C in children. Child Liver Study Group of Japan

Limited information is available regarding the histology of hepatitis C virus infection in children. The aim of this study was to determine the histological pattern of chronic hepatitis C (CHC) in children, and liver biopsy specimens from 109 pediatric patients with CHC were examined. Each biopsy specimen was evaluated based on a numerical scoring system for the stage of fibrosis (1-4), the grade of portal/periportal necroinflammation (0-4), the grade of lobular necroinflammation (0-4), and their sum (final grade). The histological lesions considered to be characteristic of chronic hepatitis were also evaluated. None of the children had liver cirrhosis, and 105 cases (97%) were stage 1 or 2. Only 4 children were stage 3. Two of these 4 cases showed hemosiderosis. A significant correlation was observed between the staging score and the final grade in the pediatric patients (r = .59; P < .0001). The histological characteristics of adult CHC, such as lymphoid aggregate, bile duct injury, and fatty changes, were also observed in the children. In conclusion, the majority of children with CHC presented with mild fibrosis, but a few showed CHC with lobular distortion and hemosiderosis. Frequent blood transfusion may aggravate hepatic lesions in pediatric CHC.     

A clinical study of persistent hypotension in patients on chronic hemodialysis

In order to clarify the pathogenesis of hypotension seen in the patients on chronic hemodialysis, we studied the vascular reactivity to exogenous vasoactive substances and the change of plasma ANP level during hemodialysis treatment. The vascular responsiveness to intravenously infused norepinephrine was decreased in hemodialysis patients, particularly in hypotensive group, compared with healthy controls (< 0.05). The blood pressure response to angiotensin II was also diminished significantly in hypotensive patients, compared with normotensive patients (p < 0.05). The plasma ANP concentration before and after each hemodialysis treatment was not different statistically between hypotensive and normotensive patients. Furthermore, the change of plasma ANP concentration was not correlated with the blood pressure change during each hemodialysis procedure. These findings suggest that the decrease of vascular responsiveness may be a factor for causing persistent hypotension in patients on chronic hemodialysis, and that the plasma ANP level is not responsible for the pathogenesis of hypotension.     

Pt-Al2O3 Cryogel with High Thermal Stability for Catalytic Combustion

The cryogel catalyst of platinum on alumina was prepared from aluminum sec-butoxide and H₂PtCl₆ through the sol-gel technique and subsequent freeze drying. The cryogel catalyst showed higher thermal stability of platinum than the corresponding xerogel or impregnation catalysts, which was ascribed to the more intimately developed platinum-alumina interaction accompanied by the encapsulation of the metal into the alumina cryogel. It was also shown that platinum accessibility was higher on the cryogel than on the xerogel despite the higher thermal stability of the metal on the formed than on the latter. For the VOC combustion, the cryogel exhibited higher activity than the xerogel and impregnation catalysts. Also for the methane combustion the cryogel showed higher activity, although it showed lower activity than the impregnation catalysts above 600 °C. By the addition of ceria as an additive to the cryogel catalyst, the CH₄ combustion activity was improved especially in the temperature region above 600 °C.