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101.
People fear risks and try to avoid them. With a basic innate drive of sensing risks and protecting safety, humans can survive both natural and man-made catastrophes. Modern science and technology considerably serve for predicting risks and lend themselves to increasing protection for humans. In recent years, however, perception and communication gaps seem to be sharpening between scientists and lay public as to what is safe and how safe is safe enough. The present paper is an attempt to illustrate the causes of such perception and communication gaps and present some empirical evidence to understand the psychological foundation of fears in the lay public.  相似文献   
102.
A 77-year-old female was admitted to our hospital because of pyrexia and a right retroperitoneal mass. Leukocytosis and other inflammatory findings were noted. Bone-marrow aspiration revealed hypercellularity with no malignant cells. An additional mass was detected sonographically in the pelvis. The serum concentration of granulocyte colony-stimulating factor (G-CSF) was highly elevated (299 pg/ml). The tumors were removed at laparotomy, and the pelvic mass was found to arise from the ileocecal mesentery. Postoperatively, white blood cell count and serum G-CSF concentrations decreased to normal levels. The mesenteric tumor showed weakly positive immunostaining for human G-CSF, and Northern and polymerase chain reaction (PCR) analyses detected CSF and its mRNA in the mesenteric tumor.  相似文献   
103.
The demand for energy in Japan is expected to increase steadily into the future, and it seems that the importance of nuclear power generation will be heightened more when the situation of our country which is not rich in energy resources is taken into account.

Furthermore, when we consider the present situation that the light water reactors have become common, recent outlook for the supply and demand for uranium resources, trends in the development of the fast breeder reactor technology, etc., the light water reactors are expected to remain dominant in the nuclear power generation of our country until at least the second half of the 21st century.

Based on such a background five PWR utilities in Japan (Hokkaido, Kansai, Shikoku, Kyushu, and the Japan Atomic Power), and Mitsubishi Heavy Industries, Ltd. have jointly started researching the Next Generation PWR which is expected to be the leading nuclear power plant taking place of APWR.  相似文献   

104.
PURPOSE: To propose a new classification of capsular block syndrome (CBS) to improve understanding of the etiology and provide effective treatment. SETTING: Shohzankai Medical Foundation, Miyake Eye Hospital, Nagoya, and Japanese Red Cross Society, Wakayama Medical Center, Wakayama, Japan. METHODS: Three groups of eyes with CBS were reviewed: eyes originally reported and diagnosed as having CBS; eyes experiencing CBS after hydrodissection and luxation of the lens nucleus; and eyes with CBS accompanying liquefied aftercataract or capsulorhexis-related lacteocrumenasia. RESULTS: In all 3 groups, the CBS occurred in eyes with a continuous curvilinear capsulorhexis (CCC). It was characterized by accumulation of a liquefied substance within a closed chamber inside the capsular bag, formed because the lens nucleus or the posterior chamber intraocular lens (IOL) optic occluded the anterior capsular opening created by the CCC. Depending on the time of onset, CBS can be classified as intraoperative (CBS seen at the time of lens luxation following hydrodissection), early postoperative (original CBS), and late postoperative (CBS with liquefied aftercataract or lacteocrumenasia). The etiology of the accumulated substance and the method of treatment are different in each type. CONCLUSION: Capsular block syndrome is a complication of cataract/IOL surgery that can occur during and after surgery. Correctly identifying the type of CBS is crucial to understanding the nature and effective treatment of this disorder.  相似文献   
105.
A specific colony of Wistar rats was found in which the common carotid artery bifurcates at an unusually caudal position, thereby the carotid sinus nerve that originates from the bifurcation is elongated. The present study was done to determine whether this elongated nerve carries baro- and chemosensations in the same manner as the carotid sinus nerve of conventional rats or of other species. In chloralose-urethane anesthetized rats of this specific colony, the afferent discharges were recorded from the elongated carotid sinus nerve in response to a phenylephrine-induced rise in blood pressure and a fall in oxygen tension, as well as an increase in carbon dioxide tension in the respiratory gas. Reflex effects of electrical stimulation of the nerve were also examined. In nerve recording, the afferent discharges of the elongated carotid sinus nerve were increased by any of the perturbations, hypertensive, hypoxic or hypercapnic. Electrical stimulation of the elongated carotid sinus nerve caused an initial rise and a subsequent fall in blood pressure, bradycardia, and an increase of respiratory volume and rate. These results confirmed that the elongated carotid sinus nerve of rats in this colony contains both baroreceptor and chemoreceptor afferent fibers. It seems that this colony of rats proffers a beneficial material which will facilitate the studies to analyze the features and reflex functions of carotid body chemoreceptors and/or carotid sinus baroreceptors.  相似文献   
106.
We observed 3 diabetic patients with intolerable dizziness followed by nausea and vomiting immediately after an initial administration of the alpha-glucosidase inhibitor, voglibose. These symptoms did not recur after discontinuation of the drug. Adverse effects as observed in these cases have not been reported previously. Since the 3 patients were relatively old (average age, 72 years old) and had various degrees of micro- and macroangiopathies, these side effects may have been associated with increased micro- and macrocirculatory disturbances in their central nervous systems through alpha-glucosidase inhibition of this agent.  相似文献   
107.
108.
Multiple oxide BaTiO3 gel fibres were prepared by the sol-gel method from Ba(OC2H5)2-Ti(O-isoC3H7)4-H2O-C2H5OH-CH3COOH and Ba(CH3COO)2-Ti(O-isoC3H7)4-H2O-CH3COOH solutions. Relatively long gel fibres of 10cm length were obtained from both solutions in the limited composition region. The latter solution in particular showed a spinnability even when it contained no water. Therefore, the occurrence of spinnability of the solution was considered to be due to the formation of linear polymers composed of bridging acetate groups such as TiO-C(CH3)-O-Ti rather than metalloxane bonding as Ti-O-Ti. Addition of water to the solutions seems to break the bridging acetate bonds and replace some of them by bridging oxygen bonds. The as-drawn gel fibres which were X-ray amorphous crystallized into BaTiO3 ceramic fibres of 5mm average length upon heating above 600 ° C. However, the gel fibres drawn from the sols without water became powdery on heating because of the lack of Ti-O-Ti metalloxane bonds. The crystallization behaviour of the BaTiO3 gel fibres is discussed based on the infrared spectroscopy, X-ray diffraction analysis and thermogravimetric-differential thermal analysis.  相似文献   
109.
The microstructure and indentation response of pressureless-sintered - and -SiC were studied using a high-resolution electron microscope and analytical electron microscopy. The materials were manufactured with boron and carbon as sintering aids. It was found that the overall porosity of the materials was very low but a large number of carbon inclusions were present. X-ray diffraction revealed the fabricated -SiC material was of the same 3C polytype as the initial starting powder; however, electron microscope observations indicated that the material contained a high density of faulting of the -forms. High-resolution imaging of grain boundaries in these materials indicated that the boundaries were very clean, and when they contained an amorphous intergranular film it was at most 0.5 to 1 nm thick. The presence of boron was not detected. Deformation due to identation took several forms. Firstly, radial cracks extending from the corners of the indent suffered little hindrance from the matrix microstructure, such that transgranular fracture was the dominant mode. Secondly, the deformation zone beneath the indentations showed copious lattice microcracks with some preferred orientation during crack formation and propagation.  相似文献   
110.
A mathematically simple spatial difference method has been applied for analysing three-dimensionally, and for illustrating graphically, the process of the development of a flame after the propane-air stoichiometric mixture is ignited. The calculated results show that the mathematical simulation can well express the process of mixture explosion in cylindrical vessels, and can evaluate the effects of laminar swirl flow on the flame development. It is concluded that the swirl motion deforms the flame front and accelerates the flame enlargement. Described also is a comparison of swirl flame calculation, with and without the centripetal effect caused by the difference in densities between burnt and unburnt gases.List of symbols A, A f , A K , A W area, flame surface area, flame element area, and wall area - b e heat penetration coefficient - C d coefficient - C p molar specific heat at constant pressure - G mass of gas - H cylinder height - h enthalpy and molar enthalpy - L effective length - M j molecular weight - n, N normal unit vector and normal vector to flame surface - p pressure - q heat input per unit mass - r c flame center location - r, R radius and vessel radius - R universal gas constant - Re Reynolds number - s b , s u flame speed and burning velocity - t time measured from spark-ignition - U c inward moving velocity of flame center - u u compression velocity of the unburnt gas just ahead of the flame front - U(u, v, w) velocity vector - v i , V i specific volume and volume of region-i - x j mole fraction of specie-j - x mass fraction of burnt gas - X(x, Y, z), X(x, r, ) orthogonal and cylindrical coordinate systems - Y j mass fraction of specie-j - Y mass fraction of burnt gas - small amount of change - change from the initial state Suffixes ij flame element number - i region or state - j chemical species  相似文献   
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