Permanent sextupole magnets

Compact but very strong sextupole permanent magnets have been assembled for use in a newly developed cold atomic beam polarized ion source. The sextupole magnetic field characteristics have been found to be satisfactory.     

Polarization-independent electroabsorption modulators using strain-compensated InGaAs-InAlAs MQW structures

The improved modulation properties of strain compensated InGaAs-InAlAs multiple quantum well (MQW) electroabsorption modulators and their modules have been demonstrated. Introduction of a 0.5% tensile strain in wells and a 0.5% compression in barriers provides highly efficient operation such as a low driving voltage (V/sub 20/ dB=1.6 V) and a large modulation bandwidth (f/sub 3/ dB>20 GHz). This is in addition to low polarization-dependence with an extinction ratio difference between TE and TM and polarization of less than 1 dB.     

Experimental study of LIM-driven,attraction-type magnetically levitated carrying system

Recently, many kinds of magnetic levitation systems have been proposed and developed for use in factory automation systems. This progress in the development depends on the appearance of new types of permanent magnets and new control theories. On the other hand, some systems have simple structures in which couples roles are given for both levitation and conveyance. As for these systems, however, many trials are needed to establish the system configurations and the control theory. The authors have developed a new magnetically levitated carrying system driven by LIM (linear-induction motor). The system can be completely detached from a guideway both in mechanical and electrical meanings. In this paper, the experimental results, especially the driving characteristics of a vehicle without any contacts to the LIM guideway, are discussed.     

Characterization of three novel monoclonal antibodies against hepatitis C virus core protein

Three novel monoclonal antibodies (MAbs) were established against a recombinant hepatitis C virus (HCV) core protein derived from cloned genotype 1b HCV cDNA. MAbs C7-50 and C8-59 recognize a conserved linear epitope represented by amino acid residues 21 to 40 of the nucleocapsid protein. MAb C8-48 is directed against a strain-specific conformational epitope located within the first 82 amino acids. A sensitive two-site MAb-based immunoradiometric assay was established using antibodies directed against distinct epitopes on the nucleocapsid protein. Processed 21 kDa core protein was detected by immunoblotting in human hepatocellular carcinoma cell lines and primary adult rat hepatocytes transfected with a cytomegalovirus promoter-driven expression construct. Immunofluorescence microscopy studies revealed a granular and vesicular cytoplasmic staining pattern. MAb C7-50 was used successfully to detect HCV core antigen in chronically infected chimpanzee liver tissue. These MAbs represent important reagents for the study of HCV biology and for the development of immunodiagnostic assays.     

A pilot study of ribavirin and interferon beta for the treatment of chronic hepatitis C

BACKGROUND: Chronic hepatitis C is a common and often progressive liver disease for which interferon alfa therapy widely spreads, but the beneficial response is frequently transient. Ribavirin is a nucleoside analog with a broad spectrum of antiviral action, and we investigated the efficacy of it in patients with chronic active hepatitis C. METHODS: We conducted a pilot study of oral ribavirin in patients with chronic active hepatitis C. Twenty-seven patients with hepatitis C virus RNA were randomly assigned to receive either 0.8-1.0 g of ribavirin daily or 3 MU of interferon beta three times weekly or combination of the two for 24 weeks. RESULTS: Ribavirin was tolerated well, and all completed the treatment schedule. Ribavirin decreased aminotransferase levels in all instances, and the mean value at termination decreased to half of the baseline level (P < 0.01), but the enzyme level increased after cessation of therapy in most cases. Ribavirin suppressed amounts of hepatitis C virus RNA in 4 of 9 patients, and 1 became negative during follow-up. Interferon alone (P < 0.05) or with ribavirin (P < 0.01) significantly decreased the viral population, resulting in sustained loss of viremia with normal enzyme levels in 2 of 9 and 3 of 9 patients, respectively, in each therapy during follow-up. CONCLUSIONS: These results indicate that ribavirin has a beneficial effect in some patients with chronic hepatitis C, although the antiviral effect is less than interferon beta. Large-scale trials are needed to determine whether the combination of interferon and ribavirin is of more benefit than interferon alone.     

A low-drive-voltage, high-speed monolithic multiple-quantum-wellmodulator/DFB laser light source

A high-speed InGaAs/InAlAs multiple-quantum-well (MQW) intensity modulator and an InGaAsP/InGaAs MQW distributed feedback laser were monolithically integrated by using a hybrid growth technique combining molecular beam epitaxy and metalorganic vapor phase epitaxy. An operating drive voltage of only 2.0 V, a 20-dB on/off ratio, and a 3-dB bandwidth greater than 15 GHz were obtained. This device operated stably in a single mode and with a side-mode suppression ratio of more than 50 dB     

Ability of surfactants to form highly loaded coal-water mixtures

Coal tends to aggregate in water. In a coal-water mixture (CWM), the higher the coal content is, the more thickened the mixture is. To highly load a CWM with coal, therefore, it is necessary to use a dispersant. The authors synthesized new types of multibranched high molecular nonionic surfactants that did not contain any alkali metal which would be harmfuls in combustion. Those surfactants were added to CWM samples containing Tatung coal pulverized by a ball mill. As a result, it was found that they contributed greatly to improving the fluidity of CWM, as briefly described below. (i) Alkylene-oxide-added multi-branched high molecular nonionic surfactants improve their ability to highly load a CWM with an increase in the molecular weight per active hydrogen atom. When the molecular weight is 3,000 to 6,000 or more, they can make a CWM containing 69% coal. (ii) Sodium salt of formalin naphthalenesulfonate condensate, a type of anionic surfactant, can increase the coal content only to a maximum of 65%. (iii) Multi-branched high molecular nonionic surfactants can make a stable CWM.     

Encephalitogenic peptide (EP) in human cerebrovascular white matter lesions

The expression of encephalitogenic peptide (EP), a 68-86 amino acid sequence of guinea pig myelin basic protein (MBP), was investigated in autopsied brains with focal cerebral damage or with diffuse white matter (WM) lesions. EP immunoreactive fibers were distributed in parallel with fibers immunoreactive for amyloid protein precursor (APP), an indicator of WM damages. EP was expressed in the periphery of cerebral infarctions and hematoma in the acute and subacute stages, but was also distributed in diffuse WM lesions due to heterogeneous causes. These data indicate that EP epitopes are exposed specifically in ongoing WM damages, and that the destruction of myelin occurs sporadically in diffuse WM lesions of varying intensity.