112 research outputs found
Abnormal Action Potentials Associated with the Shaker Complex Locus of Drosophila
Intracellular recordings of action potentials were made from the cervical giant axon in Shaker (Sh) mutants and normal Drosophila. The mutants showed abnormally long delays in repolarization. The defect is not due to abnormal Ca2+ channels, because it persists in the presence of Co2+, a Ca2+-channel blocker. On the other hand, the K+-channel blocker 4-aminopyridine causes a similar effect in normal animals, suggesting that the Sh mutant may have abnormal K+ conductance. Gene-dosage analysis of Sh shows that the defect is not due to underproduction of an otherwise normal molecule; it may be due to an abnormal molecule produced by the mutated gene. Gel electrophoresis failed to detect an abnormal protein, suggesting that, if Sh codes for a nervous system protein, it is rare. Genetic analysis of the Sh locus indicates three regions. Mutations or chromosome breaks in the two flanking regions cause Sh mutant physiology; the central region shows a "haplolethal effect"--i.e., heterozygous females are lethal
Monoclonal Antibodies against the Drosophila Nervous System
A panel of 148 monoclonal antibodies directed against Drosophila neural antigens has been prepared by using mice immunized with homogenates of Drosophila tissue. Antibodies were screened immunohistochemically on cryostat sections of fly heads. A large diversity of staining patterns was observed. Some antigens were broadly distributed among tissues; others were highly specific to nerve fibers, neuropil, muscle, the tracheal system, cell nuclei, photoreceptors, or other structures. The antigens for many of the antibodies have been identified on immunoblots. Monoclonal antibodies that identify specific molecules within the nervous system should prove useful in the study of the molecular genetics of neural development
Lyman Emitters beyond Redshift 5:The Dawn of Galaxy Formation
The 8m class telescopes in the ground-based optical astronomy together with
help from the ultra-sharp eye of the Hubble Space Telescope have enabled us to
observe forming galaxies beyond redshift . In particular, more than twenty
Ly-emitting galaxies have already been found at . These findings
provide us with useful hints to investigate how galaxies formed and then
evolved in the early universe. Further, detailed analysis of Ly
emission line profiles are useful in exploring the nature of the intergalactic
medium because the trailing edge of cosmic reionization could be close to -- 7, at which forming galaxies have been found recently. We also
discuss the importance of superwinds from forming galaxies at high redshift,
which has an intimate relationship between galaxies and the intergalactic
medium. We then give a review of early cosmic star formation history based on
recent progress in searching for Ly-emitting young galaxies beyond
redshift 5.Comment: 23 pages, 12 figures, jkas35.sty. To appear in the proceedings of the
APCTP WoFormation and Interaction of Galaxies, edited by Hyung Mok Leerkshop
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Ether stress-induced Alzheimer-like tau phosphorylation in the normal mouse brain
AbstractTau is reversibly hyperphosphorylated in the mouse brain by starvation or cold water swimming. Here, we report tau phosphorylation in the hippocampus of normal mouse after ether anesthesia, known to trigger typical stress reactions. Robust phosphorylation of tau was observed immediately and 10min after ether vapor exposure at Ser202/Thr205 and Thr231/Ser235, sites typically phosphorylated in Alzheimer brains. The phosphorylation levels returned to baseline by 1h. The most conspicuous and consistent change in the protein kinases studied was the inactivating phosphorylation of Ser9 of TPKI/GSK3β in close correspondence with tau phosphorylation. These findings show that tau phosphorylation is a rapid physiological process integral to stress response system, and suggest involvement therein of TPKI/GSK3β
Producing cluster states in charge qubits and flux qubits
We propose a method to efficiently generate cluster states in charge qubits,
both semiconducting and superconducting, as well as flux qubits. We show that
highly-entangled cluster states can be realized by a `one-touch' entanglement
operation by tuning gate bias voltages for charge qubits. We also investigate
the robustness of these cluster states for non-uniform qubits, which are
unavoidable in solid-state systems. We find that quantum computation based on
cluster states is a promising approach for solid-state qubits.Comment: 4 pages, 1 figure
The Effect of Side Traps on Ballistic Transistor in Kondo Regime
The effect of side-traps on conductance is calculated in the range of
slave-boson mean field theory, especially when there are electrodes on both
sides of the conductor.
This corresponds to an investigation of transport properties in future
ballistic transistors. An intrinsic dip as a result of the interference effect
(Fano-Kondo effect) is expected to be observed as one of interesting interplays
between physics and engineering devices.Comment: 3 pages, 5 figures. 2006 International Conference on Solid State
Devices and Materials (SSDM2006), Sept. 12-15, 2006, Yokohama, Japa
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