Genomic classification of fish nodaviruses by molecular phylogenetic analysis of the coat protein gene

A molecular phylogenetic analysis of 25 isolates of fish nodaviruses, the causative agents of viral nervous necrosis of marine fish, was performed based on the nucleotide sequences (427 bases) of the coat protein gene. These fish nodaviruses were classified into four clusters: tiger puffer nervous necrosis virus, striped jack nervous necrosis virus, berfin flounder nervous necrosis virus, and red-spotted grouper nervous necrosis virus.     

Crystalline products and their formation mechanism in thermal hydrolysis of ZrOSO4 solution

Solid products were prepared from mixtures of zirconyl carbonate and sulphuric acid solution under thermal hydrolysis at 240°C. These crystalline products and their formation mechanism were investigated by evaluating the amount of products, and by X-ray diffraction analysis and TEM observation. The solid products precipitated were zirconium oxide sulphates (ZOS, PZOS, ZrOSO₄·H₂O) and m-ZrO₂. The area and thickness of the fine plate-like crystals of ZOS increased with increasing concentration of the solution and hydrothermal treatment time. For thin starting solutions, the precipitation velocity and the amount of PZOS increased. For thick starting solutions, those of ZOS increased. For 0.5 mol/l^–1 ZrOSO₄ solution (ZS0.5) from the thin solution, PZOS crystallized early and m-ZrO₂ crystallized by releasing sulphuric acid ions in PZOS with treatment time. For ZS2.5 from the thick solution, ZrOSO₄·H₂O was crystallized by increasing the proportion of sulphuric acid ions to zirconium ions in the solution, which was caused by ZOS precipitation.     

GHTA welding phenomena of an aluminium alloy in a vacuum

The midair disintegration of the space shuttle 'Colombia', in which the total crew of 7 members was lost, occurred on 1^st February 2003. The circumstances of the crash shown on TV screens reaffirmed the public's view of the risks of space development and the importance of security. NASA has stopped any further space shuttle launches until the causes are fully investigated - a postponement of the completion of the International Space Station is inevitable. The operational life of the ISS is considered to be 10 years but it could be quite possible to prolong this if required for various reasons. Accordingly, it is highly likely that there will be requests for remodelling in order to achieve high levels of functional performance and to repair damage caused by debris impact and for other reasons. In order to meet these requirements it is essential to establish space welding technology.¹     

Regulation of adrenergic nerve-mediated contraction of canine pulmonary artery by K+ channels

The aim of the present study was to investigate the role of certain subtypes of K+ channels in nerve-evoked contractions of pulmonary artery in vitro. The lobar or segmental pulmonary arteries were dissected from dogs, cut into ring segments, and the contractile responses to electrical field stimulation (EFS) and noradrenaline were measured under isometric conditions. Addition of iberiotoxin, a big conductance Ca2+-activated K+ channel blocker, and apamin, a small conductance Ca2+-activated K+ channel blocker, did not change the resting tension but augmented the contractile responses to EFS, so that the electric stimulus frequency required to produce a half-maximal contraction (ES50) was decreased from 18.2+/-3.5 to 7.4+/-2.3 Hz (p<0.01) and from 16.8+/-2.2 to 11.4+/-2.0 Hz (p<0.05), respectively, whereas glibenclamide, an adenosine triphosphate (ATP)-sensitive K+ channel blocker, had no effect. In contrast, none of the K+ channel blockers altered the contractile response to noradrenaline. Incubation of tissues with iberiotoxin and apamin increased the release of 3H-noradrenaline evoked by EFS. We conclude that big conductance Ca2+-activated K+ channels and small conductance Ca2+-activated K+ channels may play a role in the regulation of adrenergic neurotransmission in the pulmonary artery, probably by inhibiting the exocytotic release of noradrenaline from the adrenergic nerve terminals.     

New manufacturing techniques of large forged shell rings for pressure vessels

A 250 ton hollow ingot was made for experimental purposes so that the properties of a large-sized hollow ingot could be simulated. The investigation results indicated that this ingot was suitable for forged shell rings of nuclear reactor pressure vessels (RPV). They were used in the manufacture of forged shell rings for an RPV of a 1300 MW type PWR and for an RPV of an 1100 MW type BWR using basic oxygen furnace, RH degassing, hollow ingot-making process. These shell rings had less segregation and clean inner surfaces which are attributed to the homogeneity of the hollow ingot.     

A role of lysine-43 in the inactivation of rat prorenin

1. Lysine-43 (Lys43) in the prosegment region was located within 3 x 10(-1) of catalytic sites, Asp81 and Asp266, in a stereo structure model of rat prorenin. 2. A mutant prorenin, Lys43Leu, was produced to elucidate a role of Lys43 in the inactivation of prorenin. Lys43Leu as well as the wild type were inactive at a neutral pH, and activated at an acidic pH. Its acid-activation speed was three times higher than that of the wild type. The mutant prorenin was more labile than the wild type at 55 degrees C and a neutral pH. 3. These results indicate that Lys43 forms ionic bonds with Asp81 and Asp266 to inactivate and stabilize prorenin.     

A study on the fatigue crack growth in 9% Ni steel plate: Growth rate of surface crack in a plate under arbitrarily combined tension and bending

Cyclic growth rate of a surface crack is complicated by the three dimensional stress field around the crack and also by an interaction expected between the growth rate at every position on the contour. An analysis, based on the total energy around a surface crack, derived a correlation between strain energy release rate and cyclic increase in cracked area. And the correlation was confirmed by experiments conducted, with 9% Ni steel plate, under tension, bending and combined tension and bending.     

Effect of subarachnoid haemorrhage on micro-circulation in hypothalamus and brain stem of dogs

In order to investigate the relationship between cerebral vasospasm and microvasculature in the hypothalamus and brain stem, colloidal carbon was infused into the vertebral artery at various time intervals after experimental subarachnoid haemorrhage in dogs. Experiments which demonstrated vasospasm on angiogram were always accompanied by ischaemic changes in serial sections taken from the anterior hypothalamus to the brain stem. However, when it was demonstrated by angiography that the vasospasm had disappeared, the micro-circulation was restored to normal. Electron microscopy of the hypothalamus 48 hours and one week after subarachnoid haemorrhage, demonstrated swelling of the endothelial cells, enlargement of the perivascular glia and increase in number of the pinocytic vesicles in the cytoplasm, thus showing vasogenic oedema in this area. It is assumed that in addition to the vasogenic substance in extravasated blood, changes in irritability of cerebral vessels through the vasomotor pathways in the hypothalamus and brain stem might play an important role in the production of cerebral vasospasm.