Crosstalk between microstrip transmission lines

Methods for prediction of crosstalk between microstrip transmission lines are reviewed and simplified for the weak-coupling case. Classical coupled transmission line theory is used for uniform lines, and potential and induced EMF methods are used for crosstalk between nonuniform lines. It is shown that the potential method is equivalent to classical coupled transmission line theory for the case of uniform lines. An experiment was performed for uniform coupled microstrip lines for frequencies from 50 MHz to 5 GHz, and good agreement between theory and measurement was obtained for both near- and far-end crosstalk     

The apolipoprotein E allele epsilon 4 is overrepresented in patients with the Lewy body variant of Alzheimer's disease

We determined apolipoprotein E (ApoE) genotypes in 122 autopsied demented patients. The frequency of the ApoE epsilon 4 allele was 39.6% in Alzheimer's disease (AD), 29.0% in the Lewy body variant of AD (LBV), and 6.25% in diffuse Lewy body disease. For AD and LBV patients, the epsilon 4 frequency was significantly higher than that reported in nondemented controls (10 to 15%). Therefore, LBV and AD share ApoE epsilon 4 as a genetic risk factor, providing further evidence that these conditions overlap.     

In vivo studies of an implantable energy convertor for skeletal muscle powered cardiac assist

A device that harnesses the mechanical energy of skeletal muscle contracting in a linear configuration has been implanted in goats. This energy convertor transforms muscle work to hydraulic energy that could drive a variety of cardiac assist devices. The device is mounted with a rib clamp and plate affixed to the sternum by cortical bone screws. A transcutaneous hydraulic line carries a silicon based working fluid to an external system that controls the muscle load. In 60 to 70 kg goats, the latissimus dorsi insertion was reattached to the energy convertor. A Telectronics myostimulator with intramuscular electrodes stimulated the latissimus dorsi. In acute implants, hydraulic pressures in excess of 150 psi were obtained. Chronic implantation of the device allowed system evaluation in the conscious unanesthetized animal. Two weeks after implant, hydraulic pressures in excess of 200 psi were obtained and energy transferred to the external loading system exceeded 1 J per contraction. Six weeks after implant, the device continued to cycle freely. These initial results are very promising and suggest an implantable energy convertor is feasible. Development of an energy convertor is an important step toward tether-free skeletal muscle powered cardiac assist devices.     

National survey of blindness and low vision in Lebanon

Here we report a case that presented with sudden onset of neurological symptoms and was treated with ganciclovir. Polymerase chain reaction analysis for human herpes virus-6 (HHV-6) from his cerebrospinal fluid was later found to be positive. He subsequently recovered with minimal residual neurological symptoms. Encephalitis secondary to this virus may be more common than previously thought in patients undergoing bone marrow transplantation. This condition should be considered in the differential diagnosis of sudden onset neurological symptoms after bone marrow transplantation.     

Pressure swing adsorption: Development of an equilibrium theory for gas separations

Two versions of the pressure swing adsorption process are analysed as a means for purification of the light component of a binary feed of arbitrary composition. Local equilibrium with linear, uncoupled isotherms is assumed. The results of the analysis show that a critical pressure ratio must be exceeded before complete purification is possible and that this pressure ratio increases as the light-component content of the feed decreases. When clean up of the light component is complete, pressurization with product leads to higher light-component recoveries than pressurization with feed. This difference becomes large for small separation factors, small fractions of the light component in the feed, and large pressure ratios.     

Global Asymptotical Synchronization of Chaotic Lur'e Systems Using Sampled Data: A Linear Matrix Inequality Approach

Sampled-data feedback control for master-slave synchronization schemes that consist of identical chaotic Lur'e systems is studied. Sufficient conditions for global asymptotic synchronization of such chaotic Lur'e systems are obtained using the free-weighting matrix approach and expressed in terms of linear matrix inequalities (LMIs). With the help of the LMI solvers, the sampled-data feedback control law can easily be obtained to globally asymptotically synchronize Lur'e chaotic systems. The effectiveness of the proposed method is finally illustrated via numerical simulations of chaotic Chua's circuits.     

Particle-bombardment-mediated DNA vaccination with rotavirus VP4 or VP7 induces high levels of serum rotavirus IgG but fails to protect mice against challenge

We recently reported that epidermal immunization using the PowderJet particle delivery device with plasmid vector pcDNA1/EDIM6 encoding rotavirus VP6 of murine strain EDIM induced high levels of serum rotavirus IgG but failed to protect mice against EDIM infection (Choi, A. H., Knowlton, D. R., McNeal, M. M., and Ward, R. L. (1997) Virology 232, 129-138.). This was extended to determine whether pcDNA1/EDIM4 or pcDNA1/EDIM7, which encode either rotavirus VP4 or VP7, the rotavirus neutralization proteins, could also induce rotavirus-specific antibody responses and if these responses resulted in protection. Titers of rotavirus serum IgG increased with the first dose in mice immunized with pcDNA1/EDIM7, but little or no serum rotavirus IgG was detected in mice immunized with pcDNA1/EDIM4. In vitro assays with these plasmids in rabbit reticulocyte lysates showed that VP4 was expressed but the amount was considerably lower than VP6 or VP7. To improve expression of VP4 and induction of rotavirus-specific humoral responses, the coding region of VP4 was cloned into the high-expression plasmid WRG7054 as a fusion protein containing the 22-amino-acid secretory signal peptide of tissue plasminogen activator (tPA) at its N terminus. In vitro expression of tPA::VP4 was significantly higher than unmodified VP4, and mice inoculated with WRG7054/EDIM4 generated high titers of rotavirus IgG. The coding sequence of VP7 without the first 162 nucleotides was also cloned into WRG7054, but no difference was observed between titers of serum rotavirus IgG in mice immunized with this plasmid (WRG7054/EDIM7Delta1-162) and pcDNA1/EDIM7. The rotavirus-specific IgG titers in all immune sera were predominantly IgG1 indicating induction of Th 2-type responses. None of the mice immunized with any of the VP4 or VP7 plasmids developed serum or fecal rotavirus IgA or neutralizing antibody to EDIM. When immunized mice were challenged with EDIM virus, there was no significant reduction in viral shedding relative to unimmunized controls. Therefore epidermal immunization with VP4 or VP7 alone elicited rotavirus IgG responses but did not protect against homologous rotavirus challenge.