515 research outputs found
Element Material Exposure Experiment by EFFU
The National Space Development Agency of Japan (NASDA) is planning to perform an 'Element Material Exposure Experiment' using the Exposed Facility Flyer Unit (EFFU). This paper presents an initial design of experiments proposed for this project by our company. The EFFU is installed on the Space Flyer Unit (SFU) as a partial model of the Space Station JEM exposed facility. The SFU is scheduled to be launched by H-2 rocket in January or February of 1994, then various tests will be performed for three months, on orbit of 500 km altitude, and it will be retrieved by the U.S. Space Shuttle and returned to the ground. The mission sequence is shown
Effect of Nickel Addition on Corrosion Resistance of Amorphous Iron Base Alloys
Change in the corrosion resistance of amorphous iron base alloys with addition of nickel has been studied by electrochemical methods. The addition of nickel to amorphous Fe-P-C alloys increases their corrosion resistance. In particular, it improves appreciably the corrosion resistance of the amorphous alloys with a small amount of chromium. Nickel added to the chromium-bearing amorphous iron alloys does not constitutes a passive film but promotes the formation of a passive film which is mainly composed of hydrated chromium oxyhydroxide
Effects of Alloying Elements on the Corrosion Behavior of Amorphous Cobalt-Base Alloys
Corrosion characteristics of amorphous cobalt-base alloys in 1N HCl have been investigated by immersion and electrochemical techniques. The corrosion resistance of amorphous Co-P-B alloy is intermediate between those of amorphous Fe-P-B and Ni-P-B alloys. The alloying with chromium, molybdenum, tungsten, nickel and copper is effective in improving the corrosion resistance. In particular, the addition of chromium and the combind addition of chromium with molybdenum lead to spontaneous passivation. The corrosion resistance of chromium-bearing alloy is improved by alloying with various metalloids but is lowered by an increase in boron and silicon. All alloys which passivate do not suffer pitting corrosion even by anodic polarization in 1N HCl
High Corrosion Resistance of Chromium-Bearing Amorphous Iron Alloys in Neutral and Acidic Solutions Containing Chloride
The corrosion resistance of amorphous iron alloys, whose practical application is expected because of their outstanding mechanical properties, has been studied by total immersion tests and electrochemical methods in acidic and neutral solutions containing chloride. In a 1 N NaCl solution at 30 C, 0.01-1 N HCl solutions at 30 C and in 6% FeCl_3 solutions at 40 and 60 C, the amorphous Fe-Cr-P-C and Fe-Cr-Ni-P-C alloys did not suffer pitting corrosion, and no weight losses were detected on the alloys containing 8 At% or more chromium using a microbalance after exposure for 168 hours. The polarization curves of the amorphous alloys did not exhibit the critical potential for pitting, and no anodic current densities higher than 10^ A/cm^2 were observed over the potential range 0 to 0.5 V(SCE) in 1N NaCl and 0 to 0.9 V (SCE) in 1 M H_2SO_4 by potentiostatic anodic polarization of the alloys containing 8 At% or more chromium. The high corrosion resistance of the amorphous iron alloys results partly from the presence of chromium and large amounts of phosphorus and partly from a homogeneous single phase amorphous structure
Diagnosis of idiopathic normal pressure hydrocephalus is supported by MRI-based scheme: a prospective cohort study
<p>Abstract</p> <p>Background</p> <p>Idiopathic normal pressure hydrocephalus (iNPH) is a treatable neurological syndrome in the elderly. Although the magnetic resonance imaging (MRI) findings of tight high-convexity and medial subarachnoid spaces and the ventriculo-peritoneal (VP) shunt with programmable valve are reportedly useful for diagnosis and treatment, respectively, their clinical significance remains to be validated. We conducted a multicenter prospective study (Study of Idiopathic Normal Pressure Hydrocephalus on Neurological Improvement: SINPHONI) to evaluate the utility of the MRI-based diagnosis for determining the 1-year outcome after VP shunt with the Codman-Hakim programmable valve.</p> <p>Methods</p> <p>Twenty-six centers in Japan were involved in this study. Patients aged between 60 and 85 years with one or more of symptoms (gait, cognitive, and urinary problems) and MRI evidence of ventriculomegaly and tight high-convexity and medial subarachnoid spaces received VP shunt using the height/weight-based valve pressure-setting scheme. The primary endpoint was a favorable outcome (improvement of one level or more on the modified Rankin Scale: mRS) at one year after surgery, and the secondary endpoints included improvement of one point or more on the total score of the iNPH grading scale. Shunt responder was defined by more than one level on mRS at any evaluation point in one year.</p> <p>Results</p> <p>The full analysis set included 100 patients. A favorable outcome was achieved in 69.0% and 80.0% were shunt responders. When measured with the iNPH grading scale, the one-year improvement rate was 77.0%, and response to the surgery at any evaluation point was detected in 89.0%. Serious adverse events were recorded in 15 patients, three of which were events related to surgery or VP shunt. Subdural effusion and orthostatic headache were reported as non-serious shunt-related adverse events, which were well controlled with readjustment of pressure.</p> <p>Conclusions</p> <p>The MRI-based diagnostic scheme is highly useful. Tight high-convexity and medial subarachnoid spaces, and enlarged Sylvian fissures with ventriculomegaly, defined as disproportionately enlarged subarachnoid-space hydrocephalus (DESH), are worthwhile for the diagnosis of iNPH. This study is registered with ClinicalTrials.gov, number NCT00221091.</p
Decrease in heart rates by artificial CO2 hot spring bathing is inhibited by beta(1)-adrenoceptor blockade in anesthetized rats
Hashimoto, M; Yamamoto, N, JOURNAL OF APPLIED PHYSIOLOGY, 96(1), 226-232, 2004. "Copyright 2004 by the American Physical Society."
publisherTo investigate the effects of carbon dioxide (CO_2) hot spring baths on physiological functions, head-out immersion of urethane-anesthetized, fursheared male Wistar rats was performed. Animals were immersed in water (30 or 35°C) with high-CO_2 content (〜1,000 parts/million; CO_2-water). CO_2-water for bathing was made by using an artificial spa maker with normal tap water and high-pressure CO_2 from a gas cylinder. When a human foot was immersed for 10 min in the CO_2-water at 35°C, the immersed skin reddened, whereas skin color did not change in normal tap water at the same temperature. Arterial blood pressure, heart rate (HR), underwater skin tissue blood flow, and temperatures of the colon and immersed skin were continuously measured while animals were immersed in a bathtub of water for 〜30 min at room temperature (26°C). Immersed skin vascular resistance, computed from blood pressure and tissue blood flow, was significantly lower in the CO_2-water bath than in tap water at 30°C, but no differences were apparent at 35°C. HR of rats in CO_2-water was significantly slower than in tap water at 35°C. Decreased HR in CO_2-water was inhibited by infusion of atenolol (β1-adrenoceptor blocker), but it was unaffected by atropine (muscarinic cholinoceptor blocker). Theses results suggest that bradycardia in CO_2 hot spring bathing is caused by inhibition of the cardiac sympathetic innervation. This CO_2-water maker should prove a useful device for acquiring physiological evidence of balneotherapy
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