Thermophysical properties of (U,Y)O2

We prepared polycrystalline pellets of (U,Y)O₂, containing YO_1.5 up to 11 mol.%. We performed indentation tests on the pellets, and evaluated the Young’s modulus and hardness. We measured the heat capacity and the thermal diffusivity, and evaluated the thermal conductivity. We succeeded in evaluating the effect of Y content on the thermophysical properties of (U,Y)O₂. We revealed that the Young’s modulus, hardness, and thermal conductivity of (U,Y)O₂ decreased with increasing the Y content.     

VLSI implementation of a variable-length pipeline scheme fordata-driven processors

A VLSI-oriented variable-length pipeline structure for data-driven processors is presented. Ordinary inline pipelines have the problem of minimizing the average total processing time through the pipeline, since subdivision of a function along the pipeline is usually optimized for the most complex operations in spite of the fact that simpler operations need fewer stages. As a solution to this problem, a variable-length pipeline scheme in which data go through only the necessary stages according to information contained within is proposed. The scheme has been implemented on a test chip to verify performance. The chip demonstrated a minimum fall-through time (data transmission time from input to output) of 14.4 ns and a data transmission rate in the pipeline of 59 megaword/s (that is, 1/16.9 ns) as a first-in first-out (FIFO) store. By modifying the data transfer control and allocating the processing functions corresponding to the data interval of 16.9 ns, this scheme is applicable as a high-performance processing unit for data-driven processors     

Observational examination of aggregation and migration during early phase of neurosphere culture of mouse neural stem cells

Neural stem cells (NSCs) form cell aggregates called neurospheres during serum-free culture, and this aggregation contributes primarily to neurosphere development. In the present study, we conducted an observational examination of the cell clustering of mouse NSCs in relation to their migration potential. The cell clustering became significant from 12 h after the inoculation of NSCs during the examined culture period of 48 h. Three types of clustering were observed, that is, aggregation between two single cells, and coalescence between a cell and an aggregate and that between two aggregates. The aggregation between single cells occurred during the early phase (0-24 h after inoculation). Six hours after inoculation, the average migration rate of single cells that resulted in aggregation within the subsequent 12 h was higher than that of cells that did not aggregate. Fluorescent stainings of the cytoplasm and F-actin revealed the existence of mini podia and long podia, which were possible elements that produce the driving force for the migration of singly occurring NSCs.     

Supercooled Barium Boric Oxide Melts: X-Ray Diffraction Measurements and Glass Formation

It is well-known that oxide melts easily form a glass state from a supercooled state; however, it is difficult for some oxides to transform to the glass state from the corresponding supercooled state. β-BaB₂O₄ (β-BBO) crystals are important materials for laser applications. The β-BBO crystal easily grows from the supercooled melt, and it is therefore difficult to form the BBO glass state. We attempted to make BBO glass by a containerless technique using the conical nozzle gas-jet levitation (CNL) method. We were successful in making BBO glass with a diameter of 2 mm from a highly supercooled melt without rapid quenching. In order to clarify the phase selection mechanism of the BBO melt, we performed high-energy X-ray (113.6 keV) diffraction experiments on the glassy and supercooled liquid BBO using the CNL technique at the BL04B2 beamline of SPring-8. From these experiments, the structure factor S ( Q ) of BBO glasses and supercooled melts were found to have almost the same features. From these S ( Q ), we obtained the radial distribution function T ( r )=4π rg ( r ). The analysis also showed that BBO glass and the BBO-supercooled melt have the same short-range distances. For phase selection between crystalline and glassy phases, we discuss a structure model of the BBO melt, including medium range structure based on the short-range structure obtained in this experiment.     

Structure Analysis of Molten Ba–Ge Alloys Using Electrostatic Levitation Technique Combined With High-Energy X-Ray Diffraction

High-energy synchrotron X-ray diffraction experiments were performed for clathrate-forming barium–germanium (Ba–Ge) alloys in the liquid state near the eutectic composition. The accurate structure information of highly reactive melts has been obtained by applying electrostatic levitation technique as a containerless method. The structure information obtained from the reverse Monte Carlo simulation suggests that the short-range ordering between the Ge atoms occurs with the addition of Ba atoms in the liquid Ba–Ge alloys. This can be associated with the formation of the cage-like structure composed of the Ge atoms in the liquid alloys near the eutectic composition.     

Solution Property and Irradiation Effect of Random Copolypeptides Composed of Ala and Pro Residues

Summary Poly(proline) and random copolypeptide composed of Pro and Ala residues were synthesized, and their solution properties and molecular conformation were investigated. Aqueous solutions of the polypeptide were irradiated with γ-rays above the transition temperature. It was shown that the transition temperature of the aqueous solution of the copolypeptide is influenced by Ala-residue content and γ-ray irradiation.     

Nickel Electroplating

NICKEL ELECTROPLATING has been practicallyused for decades.There is an unknown part in theplating,although this is easy to plate.Applications ofthe plating are described from the practical viewpoint.Purpose of Nickel Electroplating(1)Decorative,and corrosion resistanceNickel electroplating is deposited on iron,cupper,zinc and aluminum substrate etc.,and chromiumplating is usually deposited on nickel plating.Hexavalent chromium plating has an important effecton the corrosion resisitan…     

A case of acquired petrous cholesteatoma associated with insidious middle ear infection treated by staging the surgical procedures

STUDY OBJECTIVE: To compare the efficacy of preincision wound infiltration with bupivacaine to wound infiltration at the end of the operation. DESIGN: A prospective, randomized, double-blind study. SETTING: University medical center. PATIENTS: 56 ASA status I and II women scheduled for abdominal hysterectomy were randomly assigned to one of three treatment groups. INTERVENTIONS: Group 1 (control) received no local anesthetic infiltration. Group 2 received subcutaneous infiltration with 40 ml of bupivacaine 0.5% (pH 6.9) 15 minutes prior to incision. Group 3 received wound infiltration with a similar solution at the end of surgery. Anesthesia was induced with thiopental 3.0 mg/kg i.v., droperidol 50 micrograms/kg i.v., and sufentanil 0.5 microgram/kg i.v. and maintained with nitrous oxide 67% in oxygen and sufentanil 0.1 microgram/kg IV boluses as required. Postoperative pain was treated with morphine via a patient-controlled analgesia delivery system for 24 hours, followed by oral hydrocodone for 3 days. MEASUREMENTS AND MAIN RESULTS: The opioid consumption was recorded for 4 days postoperatively. Pain scores were measured at 4 to 8-hour intervals using 100 mm visual analog scales. There was no difference in either the opioid analgesic requirements or the pain scores between the three study groups. CONCLUSIONS: Wound infiltration, either preincision or postincision, had no clinically significant effect on the pain scores or analgesic requirements following abdominal hysterectomy.     

Evidence for the existence of L-dopa-immunoreactive neurons in the human mesencephalic region

Radioactive end labeling can be used to determine the hydrolytic rates of nuclease mimics on moderate to long lengths of RNA or DNA. However, the reliability of end labeling as an assay can vary depending on how well the unincorporated label is removed from the labeled RNA or DNA products. Therefore, gel filtration, acid precipitation, membrane diafiltration, and paper chromatography were tested to determine which technique was the most effective at such separation. The results in order of decreasing contamination by [gamma-32P]ATP were gel filtration (40%), acid precipitation (5%), diafiltration (2%), and paper chromatography (1%); and, in order of decreasing loss of RNA, were acid precipitation (30%), diafiltration (11%), gel filtration (10%), and paper chromatography (1%). In order for the resultant radioactive counts to be linearly proportional to the number of cleavage sites, the total ATP in the end-labeling reaction should be in excess of 5'-hydroxyl ends by a factor of 10 or more. Interference by nuclease mimics in the end-labeling reaction should be accounted for by including the mimics when developing a standard curve based on known concentrations of 5'-hydroxyl ends.     

Role of nitric oxide in the development of tolerance and sensitization to behavioural effects of phencyclidine in mice

1. To determine whether nitric oxide (NO) was involved in tolerance and sensitization to the effects of phencyclidine (PCP), we examined NO synthase activity and the number of NADPH-diaphorase (NADPH-d)-positive cells in discrete brain regions of saline-, acute PCP- and repeated PCP-treated mice. We also investigated the effects of a NO synthase inhibitor, NG-nitro-L- arginine methyl ester (L-NAME), on the behavioural changes induced by repeated PCP treatment in mice. 2. Acute PCP (1, 3, and 10 mg kg-1, s.c.) treatment induced dose-dependent hyperlocomotion, motor incoordination and stereotyped behaviours, consisting of sniffing, head movement and ataxia in mice. 3. In mice treated repeatedly with PCP (1, 3, and 10 mg kg-1 day-1), s.c., once a day for 14 days), the sniffing, head movement, ataxia and motor incoordination induced by PCP were attenuated (indicating the development of tolerance to these behaviours), whereas the hyperlocomotion induced by PCP was potentiated (indicating the development of sensitization to hyperlocomotion). The development of tolerance and sensitization to PCP-induced behaviours in the repeated PCP-treated mice was more marked at the dose of 10 mg kg-1 day-1) than at other doses. 4. NO synthase activity in the cerebral cortex and cerebellum, but not in the striatum and hippocampus, was significantly decreased by acute PCP (10 mg kg-1) treatment in comparison with saline treatment, and such changes in activity in the cerebral cortex and cerebellum were reversed by repeated PCP treatment (10 mg kg-1 day-1). 5. The number of neurones containing NADPH-d reactivity in the cerebral cortex, nucleus accumbens, and striatum of acute and repeated PCP-treated mice showed no change in comparison with saline-treated mice. 6. Tolerance to PCP (10 mg kg-1 day-1)-induced ataxia and motor incoordination was significantly attenuated by combined treatment with L-NAME (50 mg kg-1 day-1 i.p.). 7. Sensitization to PCP-induced hyperlocomotion was further enhanced by combined treatment with L-NAME (50 mg kg-1 day-1). However, NG-nitro-D-arginine methyl ester (D-NAME, 50 mg kg-1 day-1, i.p.), a less active enantiomer of L-NAME, had no effect, suggesting a stereospecific mechanism. 8. The PCP-induced behaviours in animals that had exhibited tolerance and sensitization to PCP (10 mg kg-1 day-1) were not influenced by acute L-NAME (5 and 50 mg kg-1, i.p.) or D-NAME (50 mg kg-1, i.p.) treatment. 9. These results suggest that NO may play an important role in the development, but not in the maintenance, of tolerance and sensitization to the effect of PCP in mice.