Shannon capacity calculation on multimode fibres

As the ultimate transmission performance of installed multimode fibres is uncertain, there is a need to understand the practical maximum capacity limit that a multimode fibre can support. The authors therefore present a new model to determine the worst-case Shannon capacity limit for multimode fibres. Detailed calculations are reported for fibre-distributed-data-interface (FDDI)-grade and OM1 fibres for operation using serial transmission with a single wavelength near 1310 nm. The method is also applicable to FDDI-grade, OM1, OM2 and OM3 fibres at all wavelengths of operation. The Shannon capacity limit of a multimode fibre is calculated for 220 m link lengths, assuming a link power budget consistent with the IEEE 10GBASE-LRM Gigabit Ethernet standard. It is shown that the Shannon capacity for non-optimised and optimised transmission spectra are at least 42 and 52 Gb/s, respectively.     

Segmentation and recognition of Chinese bank check amounts

This paper describes a system for the recognition of legal amounts on bank checks written in the Chinese language. It consists of subsystems that perform preprocessing, segmentation, and recognition of the legal amount. In each step of the segmentation and recognition phases, a list of possible choices are obtained. An approach is adopted whereby a large number of choices can be processed effectively and efficiently in order to achieve the best recognition result. The contribution of this paper is the proposal of a grammar checker for Chinese bank check amounts. It is found to be very effective in reducing the substitution error rate. The recognition rate of the system is 74.0%, the error rate is 10.4%, and the reliability is 87.7%. Received June 9, 2000 / Revised January 10, 2001     

RLS adaptive blind beamforming algorithm for cyclostationarysignals

A new cost function, which is a modification of the cost function of Castedo and Figugiras-Vidal (1995) for the adaptive blind beamforming of cyclostationary signals, is proposed. The proposed cost function enables the well-known recursive least-squares technique to be applied. Simulations demonstrate that the resulting algorithm has a faster convergence speed than the stochastic gradient-based algorithm of Castedo and Figugiras-Vidal     

Parental overprotection in Asian American children: A psychodynamic clinical perspective.

Provides an overview of the problem of overprotection in Asian families, with an emphasis on issues related to clinical theory and practice. The first section addresses parental overprotection and its manifestations in Asian culture. The second section provides an examination of potential psychopathological effects of overprotection on Asian children and adolescents. The third section discusses clinical aspects and includes 3 case illustrations; complications caused by cultural factors are emphasized. A discussion and conclusions section follows. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antibody responses of cows during an outbreak of neosporosis evaluated by indirect fluorescent antibody test and different enzyme-linked immunosorbent assays

Hairpin ribozymes with high cleavage activities were designed. An extra sequence was introduced at the 3'-end of the hairpin ribozyme to increase the binding to the substrate RNA, as compared to the wild-type hairpin ribozyme. A three-way junction (TWJ) was formed between the newly designed ribozyme and the substrate RNA. The complex with a solid TWJ showed less RNA cleavage activity than the wild-type hairpin ribozyme. However, the ribozyme with a TWJ with five unpaired bases or propandiol phosphate linkers had higher cleavage activity than the parent ribozyme without the TWJ. When a cis-cleavage system, in which the 5'-end of the substrate RNA was conjugated to the 3'-end of the ribozyme, was employed, the complex with the TWJ containing unpaired bases was also cleaved faster than the complex with the solid TWJ. This suggested that these differences in the cleavage activities were derived from the confirmation, and this was proven by nondenaturing gel electrophoresis. The TWJ hairpin ribozyme containing unpaired bases is able to bind strongly with substrate RNAs and to cleave them efficiently. Since the three-way ribozyme presented here is more active than the wild-type ribozyme, this type of ribozyme can serve as a more efficient tool to control RNA activities in vitro and in vivo.     

Conformational state-dependent effects of halothane on cardiac Na+ current

BACKGROUND: The Na+ channel is voltage gated and characterized by three distinct states: closed, open, and inactivated. To identify the effects of halothane on the cardiac Na+ current (I(Na)) at various membrane potentials, the effects of 1.2 mM halothane at different holding potentials (V(H)) on I(Na) were examined in single, enzymatically isolated guinea pig ventricular myocytes. METHODS: The I(Na) was recorded using the whole-cell configuration of the patch-clamp technique. Currents were generated from resting V(H)s of -110, -80, or -65 mV. State-dependent block was characterized by monitoring frequency dependence, tonic block, and removal of inactivation by veratridine. RESULTS: Halothane produced significant (P < 0.05) V(H)-dependent depressions of peak I(Na) (mean +/- SEM): 24.4 +/- 4.1% (V(H) = -110 mV), 42.1 +/- 3.4% (V(H) = -80 mV), and 75.2 +/- 1.5% (V(H) = -65 mV). Recovery from inactivation was significantly increased when cells were held at -80 mV (control, tau = 6.0 +/- 0.3 ms; halothane, tau = 7.1 +/- 0.4 ms), but not at -110 mV. When using a V(H) of -80 mV, halothane exhibited a use-dependent block, with block of I(Na) increasing from 8.6 +/- 1.4% to 30.7 +/- 3.5% at test pulse rates of 2 and 11 Hz, respectively. Use-dependent inhibition was not apparent at V(H) of -110 mV. When inactivation of I(Na) was removed by exposure to 100 microM veratridine, no significant difference was observed in the depressant effect of halothane at both V(H)s: 26.6 +/- 4.5% (V(H) = -80 mV) and 26.4 +/- 5.6% (V(H) = -110 mV). CONCLUSIONS: The present findings indicate that the depressant action of halothane on cardiac I(Na) depends on the conformational state of the channel. As more channels are in the inactivated state, the more potent is the effect of halothane. Removal of channel inactivation by veratridine abolished the dependence of the halothane effect on V(H), but depression of the current was still evident. These results indicate a complex interaction between halothane and the various conformational states of the Na+ channel.     

Homotopy analysis of nonlinear progressive waves in deep water

This paper describes the application of a recently developed analytic approach known as the homotopy analysis method to derive a solution for the classical problem of nonlinear progressive waves in deep water. The method is based on a continuous variation from an initial trial to the exact solution. A Maclaurin series expansion provides a successive approximation of the solution through repeated application of a differential operator with the initial trial as the first term. This approach does not require the use of perturbation parameters and the solution series converges rapidly with the number of terms. In the framework of this approach, a new technique to apply the Padé expansion is implemented to further improve the convergence. As a result, the calculated phase speed at the 20th-order approximation of the solution agrees well with previous perturbation solutions of much higher orders and reproduces the well-known characteristics of being a non-monotonic function of wave steepness near the limiting condition.     

Enhanced reliability for low-temperature gate dielectric of MOS devices by N2O or NO plasma nitridation

Silicon MOS capacitors fabricated solely by low-temperature processes (under 600 °C) are treated with nitridation using N₂O or NO plasma. Their properties are investigated at room temperature under high-field stress. It is found that both kinds of plasmas are effective in improving the gate-oxide hardness against stress-induced damage, which is characterized by a smaller shift in flatband voltage and smaller increase in interface states after the stress. Moreover, NO-nitrided device shows better performance than N₂O-nitrided one. These results show that plasma nitridation has positive effects on the reliability of low-temperature-fabricated devices, which play an important role in flat-panel display systems on glass.     

Evaluating the Impact of Partial Factorial Invariance on Selection in Two Populations.

Studies of factorial invariance examine whether a common factor model holds across multiple populations with identical parameter values. Partial factorial invariance exists when some, but not all, parameters are invariant. The literature on factorial invariance is unclear about what should be done if partial invariance is found. One approach to this problem evaluates the impact of partial invariance on accuracy of selection on the basis of a composite of the measures whose factor structure is being studied. Assuming a single-factor model holds, accuracy of selection using the composite is evaluated under varying degrees of partial invariance. A variety of examples are presented with discussion of extensions and limitations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Structural characteristics of chemical vapor polymerized polypyrrole/polycaprolactam fiber composites

Structural characteristics of polypyrrole (PPy)‐coated polycaprolactam (PA6) fiber composites prepared by chemical vapor deposition, in the presence of ferric chloride as the oxidizing agent, were investigated. A multi‐layered coating structure was observed by transmission electron microscopy (TEM), where a compact and denser layer existed between the PPy and PA6 fibers with two diffused layers on each side of the denser layer. The compact layer had a thickness of 200–300 nm. The experimental results show that there was no chemical interaction between PPy and PA6 in the PPy‐coated PA6 fibers. However, there was a stronger interaction between PPy and PA6 molecules in the interphase of PPy‐coated PA6 fiber after heat treatment at elevated temperature. The surface morphology of PPy‐coated PA6 fibers changed with the application of different processing treatments, e.g. swelling and heat treatment. Copyright © 2005 Society of Chemical Industry