Differences in virus receptor for type I and type II feline infectious peritonitis virus.

Feline infectious peritonitis viruses (FIPVs) are classified into type I and type II serogroups. Here, we report that feline aminopeptidase N (APN), a cell-surface metalloprotease on the intestinal, lung and kidney epithelial cells, is a receptor for type II FIPV but not for type I FIPV. A monoclonal antibody (MAb) R-G-4, which blocks infection of Felis catus whole fetus (fcwf-4) cells by type II FIPV, was obtained by immunizing mice with fcwf-4 cells which are highly susceptible to FIPV. This MAb also blocked infection of fcwf-4 cells by type II feline enteric coronavirus (FECV), canine coronavirus (CCV), and transmissible gastroenteritis virus (TGEV). On the other hand, it did not block infection by type I FIPVs. MAb R-G-4 recognized a polypeptide of relative molecular mass 120-130 kDa in feline intestinal brush-border membrane (BBM) proteins. The polypeptide possessed aminopeptidase activity, and the first 15 N-terminal amino acid sequence was identical to that of the feline APN. Feline intestinal BBM proteins and the polypeptide reacted with MAb R-G-4 (feline APN) inhibited the infectivity of type II FIPV, type II FECV, CCV and TGEV to fcwf-4 cells, but did not inhibit the infectivity of type I FIPVs

Evaluation of scanning earth sensor mechanism on engineering test satellite 4

The results of the analysis and the evaluation of flight data obtained from the horizon sensor test project are described. The rotary mechanism of the scanning earth sensor composed of direct drive motor and bearings using solid lubricant is operated satisfactorily. The transmitted flight data from Engineering Test Satellite IV was evaluated in comparison with the design value

Giant directional dichroism of terahertz light in resonance with magnetic excitations of the multiferroic oxide BaCo2_2Ge2_2O7_7

We propose that concurrently magnetic and ferroelectric, i.e. multiferroic, compounds endowed with electrically-active magnetic excitations (electromagnons) provide a key to produce large directional dichroism for long wavelengths of light. By exploiting the control of ferroelectric polarization and magnetization in a multiferroic oxide Ba$_2$CoGe$_2$O$_7$, we demonstrate the realization of such a directional light-switch function at terahertz frequecies in resonance with the electromagnon absorption. Our results imply that this hidden potential is present in a broad variety of multiferroics

Ferrimagnetic spin-1/2 chain of alternating Ising and Heisenberg spins in arbitrarily oriented magnetic field

The ferrimagnetic spin-1/2 chain composed of alternating Ising and Heisenberg spins in an arbitrarily oriented magnetic field is exactly solved using the spin-rotation transformation and the transfer-matrix method. It is shown that the low-temperature magnetization process depends basically on a spatial orientation of the magnetic field. A sharp stepwise magnetization curve with a marked intermediate plateau, which emerges for the magnetic field applied along the easy-axis direction of the Ising spins, becomes smoother and the intermediate plateau shrinks if the external field is tilted from the easy-axis direction. The magnetization curve of a polycrystalline system is also calculated by performing powder averaging of the derived magnetization formula. The proposed spin-chain model brings an insight into high-field magnetization data of 3d-4f bimetallic polymeric compound Dy(NO_3)(DMSO)_2Cu(opba)(DMSO)_2, which provides an interesting experimental realization of the ferrimagnetic chain composed of two different but regularly alternating spin-1/2 magnetic ions Dy^{3+} and Cu^{2+} that are reasonably approximated by the notion of Ising and Heisenberg spins, respectively.Comment: 11 pages, 6 figure