High-silica multimode channel waveguide structure for minimizing fiber-waveguide-fiber coupling loss

The optimum structure for high-silica channel waveguides which are connected to input and output graded-index fibers having a 50-μm core diameter and a 1.0-percent refractive-index difference is studied theoretically and experimentally. Theoretical optimum waveguide structure is obtained on the basis of ray optic analysis. For the step-index waveguide with 1.0-percent refractive-index difference, the theoretical minimum coupling loss (input coupling loss + output coupling loss) is 1.7 dB for an optimum core of 38 μm both in depth and width. For the graded-index waveguide with parabolic-index profile in the depth direction and step-index profile in the width direction, the theoretical coupling loss is 1.1 dB for an optimum core of 38 μm in width and 50 μm in depth. These estimations were in good agreement with the experimental results, which were 1.8 dB for the step-index waveguide and 1.3 dB for the graded-index waveguide.     

Hybrid integration of a laser diode and high-silica multimode optical channel waveguide on silicon

An InGaAsP laser diode with 1.34 ?m wavelength and a high-silica multimode optical waveguide were integrated on a common Si substrate using an alignment guide, which is formed simultaneously with the waveguide, for laser diode mounting. The laser-waveguide coupling efficiency was 30%.     

A Microprocessor-Based Robot Manipulator Control with Sliding Mode

The application of a sliding-mode control based on a Variable Structure System (VSS) for a multijoint manipulator is presented. The high-gain effect of a sliding-mode control suppresses the complicated interactions between each joint of a robot arm. The resulting system is completely robust whereas the obtained control law is simple and easy to apply to on-line computer control. In this-paper, the practical sliding-mode controller, which has a simple nonlinear compensator and proper continuous function, is implemented for a two-linkage manipulator. The validity of this technique is confirmed in experiments where the system shows robust performance in spite of the existing nonlinear interactions and unknown parametric changes. In addition, this sliding-mode control is improved to track the desired path.     

Considerations on the equivalence between non‐uniform transmission lines

We investigate the relation of equivalence between non‐uniform lossless transmission lines (LC lines or lines, for short) with sectionally smooth distributed parameters (series inductance L(x) and shunt capacitance C(x) per unit length, x being the spatial variable). The equivalence condition is derived by heuristic and well‐grounded inference. The condition provides us with the basis on which we can generate by rote a line equivalent to a fixed original line according to a specified change of spatial variable (elasticity function). The concept of intermediary lines between a pair of equivalent lines is introduced to enhance precise understanding of the condition and the procedure to generate equivalent lines. In addition, fused parameters are defined as a generalization of distributed parameters, in terms of which the argument and formulas are developed in a brief and inclusive manner. It is shown to be possible, on generating equivalent lines, to preassign a fused parameter of the equivalent line or one of the associated intermediary lines instead of specifying the elasticity function. Equivalent lines thus obtained are called conditioned equivalent lines. We discuss how to get conditioned equivalent lines as well as equivalency tests of arbitrarily given pair of LC lines to present some comprehensible and promising methods involving a versatile, graphical technique. We also refer to such interesting topics as a normalization of LC lines, a kind of conservation law of fused parameters between equivalent lines and the scope of realizable characteristics by LC lines conditioned in an arbitrary way. Some formerly known equivalence conditions are located appropriately in the context of our theory. Further, the equivalence condition is shown to be not only sufficient but also necessary for LC lines whose distributed parameters may have a finite number of points of discontinuity by invoking a theorem for an inverse scattering problem. Copyright © 2005 John Wiley & Sons, Ltd.     

Annotated references on neutron and photon production from thick targets bombarded by charged particles

The literature on neutron and photon production from thick targets bombarded by charged particles has been surveyed. The survey covers fourteen journals and some internal reports and conference proceedings, mainly from 1965 up to June 1984. For each paper, applicable information is listed on type and energy of the projectile, the accelerator used, composition and thickness of the target, the experimental method, the calculation, and the quantities obtained. The references on neutron and on photon production are accessed through two indices which list the available projectile-target combinations and the projectile energy range.     

Identification of a novel cDNA clone encoding protein tyrosine kinase in murine skin

Tyrosine phosphorylation is widely recognized as playing important roles in cell differentiation, proliferation, and carcinogenesis. We have used the polymerase chain reaction (PCR) method to identify protein tyrosine kinases that are expressed in the skin. Mixed oligonucleotide probes were used to amplify and screen a neonatal murine skin cDNA pool for clones encoding amino acid contiguities whose conservation is characteristic of the protein tyrosine kinase family. When the PCR products were sequenced, 13 distinct clones were found, of which one is novel to date and has provisionally been named tks (for tyrosine kinase identified from skin). Sequence homology comparison showed that the tks gene is homologous to the src and fes/fps families. Northern blotting using PCR products of tks as a probe revealed that the mRNA of tks is detected ubiquitously and weakly in other tissues such as brain, lung, liver, thymus and kidney. This fact suggests that the tks gene is expressed in widely distributed cell types.     

Clinical assessment of complement activation and leukocyte kinetics during cardiopulmonary bypass: the effect of cepharanthine

Complement activation and leukosequestration to the lung was studied during cardiopulmonary bypass in eleven patients undergoing cardiac operation without blood transfusion. Six patients (group I) received methylprednisolone before and after the bypass, and the other five (group II) received cepharanthine (biscoclaurin alkaloid) before the bypass associated with methylprednisolone therapy. Leukosequestration to the lung was observed at the time of reperfusion of the lung only in group I, although complement activation estimated by the increase of C 4 a and C 3 a was quite similar in both group. Cepharanthine prevented the sequestration of the leukocyte to the lung may be by its membrane stabilizing effect.     

A novel variant of acquired epidermolysis bullosa with autoantibodies against the central triple-helical domain of type VII collagen

Epidermolysis bullosa acquisita and bullous systemic lupus erythematosus are autoimmune bullous disorders, with tissue-bound and circulating autoantibodies reactive with the noncollagenous NC1 domain of type VII collagen (C-VII). Here, we describe a novel acquired bullous dermatosis with autoantibodies against the triple-helical domain of C-VII. Three patients, all Japanese children, presented with widespread inflammatory tense blisters. Histologically, subepidermal tissue separation was noted with inflammatory infiltrate in the superficial dermis. Direct immunofluorescence staining revealed linear IgG/C3 deposits along the dermal-epidermal junction. Circulating IgG anti-basement membrane zone autoantibodies stained the dermal side of normal skin separated with 1 M NaCl. Direct and indirect immunoelectron microscopy using colloidal gold labeling showed that patient sera reacted with anchoring fibrils. The gold particles were localized both near the lamina densa and on the central banded portion of the fibrils. The sera reacted with C-VII in immunoblots. Epitope analyses with natural and recombinant fragments of C-VII disclosed that the sera did not recognize the NC1 domain of C-VII, but the central triple-helical domain of this anchoring fibril protein. Thus, the present probands show a hitherto unrecognized variant of epidermolysis bullosa acquisita, with autoantibodies against epitopes in the collagenous domain of C-VII.