A glyco-phosphoprotein in human milk

A highly glycosylated phosphoprotein (HGPP) was isolated from a human casein fraction by reversed-phase high-performance liquid chromatography. This component contained carbohydrates to approximately 38.2% (w/w) and phosphorus to approximately 1.6% (w/w). The molecular weight of this HGPP as estimated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis approximately 41,000. Ultracentrifugal analysis revealed that the sedimentation coefficient of the HGPP was 2.6S in a buffer at pH 7.0 and 27 degrees C, but this component interacted with human k-casein and formed a complex with s = 10.4S.     

Pyrrolizidine Alkaloids Mediate Host-Plant Recognition by Ovipositing Females of an Old World Danaid Butterfly, Idea leuconoe

A giant danaid butterfly, Idea leuconoe, specializes on apocynaceous plants such as Parsonsia laevigata, which has been reported to contain pyrrolizidine alkaloids. Females of I. leuconoe deposited eggs in response to methanolic extract of P. laevigata, and subsequent bioassay-guided fractionation of the extract revealed that phytochemicals crucial for host recognition by ovipositing females are Parsonsia-specific macrocyclic pyrrolizidine alkaloids including parsonsianine, parsonsianidine, and 17-methylparsonsianidine. Parsonine, another P. laevigata pyrrolizidine component with a keto-dihydropyrrolizine moiety that is closely related in structure to male pheromones of the butterfly, and several nonhost pyrrolizidine alkaloids were entirely inactive. We interpret these data as strong evidence for an ancestral association through herbivory between danaid butterflies and pyrrolizidine alkaloids.     

Differential regulation of mitogen-activated protein kinase kinase 4 (MKK4) and 7 (MKK7) by signaling from G protein beta gamma subunit in human embryonal kidney 293 cells

Heterotrimeric G protein beta gamma subunit (Gbeta gamma) mediates signals to two types of stress-activated protein kinases, c-Jun NH2-terminal kinase (JNK) and p38 mitogen-activated protein kinase, in mammalian cells. To investigate the signaling mechanism whereby Gbeta gamma regulates the activity of JNK, we transfected kinase-deficient mutants of two JNK kinases, mitogen-activated protein kinase kinase 4 (MKK4) and 7 (MKK7), into human embryonal kidney 293 cells. Gbeta gamma-induced JNK activation was blocked by kinase-deficient MKK4 and to a lesser extent by kinase-deficient MKK7. Moreover, Gbeta gamma increased MKK4 activity by 6-fold and MKK7 activity by 2-fold. MKK4 activation by Gbeta gamma was blocked by dominant-negative Rho and Cdc42, whereas MKK7 activation was blocked by dominant-negative Rac. In addition, Gbeta gamma-mediated MKK4 activation, but not MKK7 activation, was inhibited completely by specific tyrosine kinase inhibitors PP2 and PP1. These results indicate that Gbeta gamma induces JNK activation mainly through MKK4 activation dependent on Rho, Cdc42, and tyrosine kinase, and to a lesser extent through MKK7 activation dependent on Rac.     

A High-Speed Optical Data Highway for Industrial Control Systems

Recent application of distributed control systems to large-and medium-scale industrial plants requires effective and high-speed communication among the control devices each other to ensure high-performance operation.     

Characteristics of a crossed-wire scatterer without a junction point of an incident wave of circular polarization

A crossed-wire scatterer has the wires displaced in the backscattering direction, and is able to scatter an incident wave of circular polarization in such a way that the backscattering wave has the same rotational sense as that of the incident wave. The radiation performance of the scatterer is improved by bending the horizontal and the vertical wires. Arrays consisting of crossed-wire scatterers are constructed and the backscattering cross sections (BSCS's) are calculated. It is revealed that the increase in the current amplitude due to the mutual effects among the array elements contributes to enhancement in the BSCS. It is also shown that a maximum value of the BSCS of an array of3 times 3bent crossed-wire scatterers is 1.8 times as large as that of a dihedral corner reflector which has the same aperture area. The BSCS's as a function of the angle of incidence are presented with experimental results at a frequency of 9.375 GHz.     

Study on an after-laying test for a long-distance GIL

Technologies for the after-laying test of long-distance SF₆ gas insulated transmission line (GIL) have been developed for the detection of partial discharge (PD) and contact defects. We constructed a long (168 m) test line in a deep tunnel and clarified the propagation characteristics of PD signals through the GIL as well as the spatial sensitivity and S/N characteristics of PD sensors for locating metallic particles. We have also proposed the application of a fiber-optic temperature distribution sensor for locating contact defects and confirmed the validity of this sensor for the GIL test line     

Application of AlGaAs/GaAs HBTs for wideband direct-coupled amplifiers

An AlGaAs/GaAs HBT direct-coupled amplifier has been designed and its characteristics described for the first time. The amplifier consists of two HBTs and three resistors without level-shift diodes. A superior amplifier performance of 11 dB gain with a 4 GHz bandwidth was obtained.     

Chlorine isotope fractionation during reductive dechlorination of chlorinated ethenes by anaerobic bacteria

Chlorine isotope fractionation during reductive dechlorination of trichloroethene (TCE) and tetrachloroethene (PCE) to cis-1,2-dichloroethene (cDCE) by anaerobic bacteria was investigated. The changes in the 37Cl/35Cl ratio observed during the one-step reaction (TCE to cDCE) can be explained by the regioselective elimination of chlorine accompanied by the Rayleigh fractionation. The fractionation factors (alpha) of the TCE dechlorination by three kinds of anaerobic cultures were approximately 0.994-0.995 at 30 degrees C. The enrichment of 37Cl in the organic chlorine during the two-step reaction (PCE to cDCE) can be explained by the random elimination of one chlorine atom in the PCE molecule followed by the regioselective elimination of one chlorine atom in the TCE molecule. The fractionation factors for the first step of the PCE dechlorination with three kinds of anaerobic cultures were estimated to be 0.987-0.991 at 30 degrees C using a mathematical model. Isotope fractionation during the first step would be the primary factor for the chlorine isotope fractionation during the PCE dechorination to cDCE. The developed models can be utilized to evaluate the fractionation factors of regioselective and multistep reactions.     

Incremental learning methods with retrieving of interfered patterns

There are many cases when a neural-network-based system must memorize some new patterns incrementally. However, if the network learns the new patterns only by referring to them, it probably forgets old memorized patterns, since parameters in the network usually correlate not only to the old memories but also to the new patterns. A certain way to avoid the loss of memories is to learn the new patterns with all memorized patterns. It needs, however, a large computational power. To solve this problem, we propose incremental learning methods with retrieval of interfered patterns (ILRI). In these methods, the system employs a modified version of a resource allocating network (RAN) which is one variation of a generalized radial basis function (GRBF). In ILRI, the RAN learns new patterns with a relearning of a few number of retrieved past patterns that are interfered with the incremental learning. We construct ILRI in two steps. In the first step, we construct a system which searches the interfered patterns from past input patterns stored in a database. In the second step, we improve the first system in such a way that the system does not need the database. In this case, the system regenerates the input patterns approximately in a random manner. The simulation results show that these two systems have almost the same ability, and the generalization ability is higher than other similar systems using neural networks and k-nearest neighbors.     

Preparation and biological evaluation of hydroxyapatite-coated nickel-free high-nitrogen stainless steel

Calcium phosphate was formed on nickel-free high-nitrogen stainless steel (HNS) by chemical solution deposition. The calcium phosphate deposition was enhanced by glutamic acid covalently immobilized on the surface of HNS with trisuccinimidyl citrate as a linker. X-ray diffraction patterns and Fourier transform infrared spectra showed that the material deposited on glutamic acid-immobilized HNS within 24 h was low-crystallinity calcium-deficient carbonate-containing hydroxyapatite (HAp). The biological activity of the resulting HAp-coated HNS was investigated by using a human osteoblast-like MG-63 cell culture. The HAp-coated HNS stimulated the alkaline-phosphate activity of the MG-63 culture after 7 days. Therefore, HAp-coated HNS is suitable for orthopedic devices and soft tissue adhesion materials.