One-dimensional device model of the npn bipolar transistor including heavy doping effects under fermi statistics

Carrier transport equations extended to Fermi statistics will be given with characteristic parameters, including heavy doping effect. These equations will be solved numerically by introducing a new method for calculating the parameters. Calculated results will accurately reproduce the significant decrease in transistor current gain with a high impurity concentration at emitter-base junction.     

Effect of clofibrate on cholesterol metabolism in rats treated with polychlorinated biphenyls

Serum and hepatic cholesterol content in rats treated with polychlorinated biphenyls (PCBs, KC-400) were increased compared to those of control rats. This increase of cholesterol content was reduced to control level by simultaneous administration of ethyl p-chlorophenoxyisobutyrate (CPIB). Also, when lecithin-cholesterol acyltransferase (LCAT) (EC. 2.3.1.43) activity was expressed as the net cholesterol esterification, the acyltransferase activity in rats treated with PCBs was elevated, while the elevated acyltransferase activity was brought to control level by simultaneous administration of CPIB. On the other hand, the amount of bile of rats treated with CPIB, PCBs and PCBs-CPIB was increased, but free and total cholesterol content in bile of these treated rats was decreased to 40–60% of those of control rats. Moreover, cytochrome P-450 content in liver microsomes of rats treated with CPIB, PCBs and PCBs-CPIB was increased. At the same time, cholesterol-metabolizing activity in liver microsomes of rats treated with CPIB, PCBs and PCBs-CPIB also was elevated. Similar results were obtained for drug metabolizing (aniline hydroxylation and aminopyrine N-demethylation) activity. In addition, the amount of bile acids excreted from rats treated with CPIB, PCBs and PCBs-CPIB was increased compared to that of control rats. These results suggest that hypercholesterolemia induced by oral ingestion of PCBs is recovered by CPIB treatment and that this hypocholesterolemic effect of CPIB may be related partly to the elevation of hepatic mixed function oxidase activity for cholesterol catabolism.     

Suppression of the benzylpenicilloyl- (BPO) specific IgE formation with isologous anti-idiotypic antibodies in BALB/c mice

In vivo effects of actively produced or passively administered isologous anti-idiotypic antisera (aId) on the benzylpenicilloyl- (BPO) specific IgE and IgG formation in BALB/c mice have been studied. Isologous anti-BPO aId were raised in BALB/c mice by immunization with purified anti-BPO antibodies isolated from ascites induced with BPO-bovine gamma-globulin in the same mouse strain. Mice producing isologous anti-BPO aId exhibited long-term suppression of BPO-specific IgE and IgG antibody responses induced by BPO-ovalbumin (BPO-OVA) in aluminum hydroxide. Simultaneously, they produced increased amounts of anti-BPO aId after each challenge with the BPO-OVA antigens. Passive administration of isologous anti-BPO aId into syngeneic mice previously sensitized with BPO-OVA caused depression of BPO-specific IgE antibody levels for 2 to 3 weeks. When anti-BPO IgE had again reached its previous level, passively administered aId had decreased to the level of untreated mice. Passive administration of anti-BPO aId also depressed the primary anti-BPO IgE formation for 2 to 3 weeks. In all these experiments the IgE antibody formation against the carrier proteins used for BPO-antigens was not affected. These results show that IgE and IgG antibodies share major idiotypic determinants and that IgE production is accessible to regulation by aId.     

Construction of a System Dynamics Model by Principal Component Analysis

Behaviormetrika - In the present paper we present a method of constructing a system dynamics model. When multiple variables are given, we sum them up by principal component analysis. By utilizing...     

Guest editorial. Code division multiple access networks. I

This special issue covers the topics: power control, multiuser receiver and joint detection, network aspects, adaptive equalisation, coding aspects, broadband CDMA systems, and optical systems     

Regulation of the biosynthesis of platelet-activating factor in alveolar macrophages

Activities of enzymes which metabolize lysoplatelet-activating factor (lysoPAF) and platelet-activating factor (PAF) were studied in rabbit alveolar macrophage lysates. Substantial acetyltransferase activity was noted in the presence of 100 μM acetyl-coenzyme A (CoA), and this activity was increased in A23187-stimulated cell lysate. On the other hand, in the absence of exogenous acetyl-CoA, lysoPAF was mainly acylated through a transacylation pathway rather than by acetyltransferase in both control and A23187-stimulated cell lysates. We confirmed that the intracellular concentration of acetyl-CoA is relatively low. The observations suggest that the transacylation system may play an equally important role in the regulation of the availability of lysoPAF in intact cells. Intracellular lysoPAF was also maintained at relatively low levels. Interestingly, large amounts of PAF were produced even in unstimulated cells upon addition of an excess of exogenous lysoPAF, suggesting that generation of an adequate amount of lysoPAF within cells may be sufficient to trigger PAF synthesis in this type of cells. Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989. Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989.     

A fission yeast gene encoding a protein that preferentially associates with curved DNA

We searched for fission yeast (Schizosaccharomyces pombe) proteins that preferentially bind to a synthetic curved DNA sequence, by means of a DNA-binding gel shift assay in the presence of an excess amount of a non-curved DNA sequence as a competitor. We identified such a protein in S. pombe. The protein, thus purified, has an apparent molecular weight of 42 000, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It was suggested that this protein (42 K-protein) recognizes and binds to a curved DNA structure in a given nucleotide sequence, although it also binds to a non-curved DNA sequence with lower affinity. As its putative coding sequence, a 1·9-kilobase genomic DNA from S. pombe was cloned and sequenced. Sequencing of a cDNA clone also revealed the existence of an open reading frame, with no intron, encoding a 381-amino-acid protein with a calculated molecular mass, 41 597. This protein appears to be located in the nucleus. The predicted protein sequence revealed that the 42 K-protein exhibits no significant similarity to any other known proteins, except to a hypothetical protein of Caenorhabditis elegans.     

A 1/3-in 410000-pixel CCD image sensor with feedback field-plateamplifier

The design considerations and performance of a 1/3-in format 410000-pixel interline transfer charge coupled device (CCD) (IL-CCD) image sensor are described. Some techniques have been introduced in order to shrink the pixel size to 6.4(H)×7.5(V) μm without any deterioration in dynamic range and, signal-to-noise (S/N) ratio. The photodiode structure is designed to reduce the knee effect so as to avoid an overflow of the vertical CCD (V-CCD) register up to 500 times the saturating illumination. A depleted-well CCD structure is introduced to maintain the maximum charge-handling capability of 92000 electrons/packet in the V-CCD register, and high enough transfer efficiency of the horizontal CCD (H-CCD) registers with 5-V_p-p pulse driving. A feedback field-plate amplifier (FFPA) is introduced to raise the sensitivity of the output amplifier to 16.2 μV/electron in order to obtain a large enough S/N ratio to the background noise of the peripheral circuits in a video camera