Miniaturised two-stage balanced Ku-band CPW MMIC amplifier using impedance transforming couplers

A two-stage balanced Ku-band coplanar waveguide amplifier design is presented which has been miniaturised by using impedance transforming couplers which considerably reduce the required matching networks to the MESFETs. The amplifier, measuring only 2*1.7 mm/sup 2/, exhibits a gain of 13.7 dB with less than +or-0.2 dB of ripple over the range 14-16 GHz.<>     

Heterotopic replantation

In multidigital amputations, it is sometimes better to replant an amputated finger to a different proximal part if a better function can be expected in this position. In our clinical material between October 1991 and March 1994, heterotopic replantation was performed in twelve digits in eleven patients. Three fingers were replanted to the thumb, three to the index, four to the middle, and two to the ring fingers. The functional results were satisfying. The total active range of motion was on an average 24% of a normal finger. Static two-point discrimination was 8.5 mm on an average, and the values for the Semmes-Weinstein test ranged between 3.61 and 6.5. A heterotopic replantation is of special value for primary thumb reconstruction.     

Thermal and hydraulic performance of a modified two-stage evaporative cooler

The thermal and hydraulic performance of a modified two-stage evaporative cooler is evaluated. Variables considered are the mode of operation, packing thickness, mass flow rate of the water flowing to the precooler, and the mass flux of water flowing over the packing media. The effectiveness of the system increased with the increase of the mass flow rate of water flowing to the precooler, decreasing the mass flux of water flowing to the packing, and with the increase of the packing thickness. The effectiveness of the system with structured packing was higher than that with sheathy leaf base or natural fiber packing.The air-side pressure drop per unit length in the direction of air flow was nearly constant when the structured packing was used. For the sheathy leaf and natural fiber packings, the air pressure drop increased at a uniform rate as the mass flux of water flowing over the packing increased. The air pressure drop was lowest for the setup with the structured packing.     

Bodies, antibodies, and neighborhood-density effects in masked form priming.

Facilitatory priming effects due to similarity of orthographic form are obtained for high-N target words provided that they have low-frequency bodies and the body is shared between the prime and target (e.g., perd-HERD). Conversely, it is shown that low-N target words show priming regardless of the frequency of the body, provided that the prime and target do not share the same body (e.g., drice-DRIVE). If the body is shared, then priming occurs only for targets with low-frequency bodies. These results suggest that neighborhood density should be defined in terms of both individual letter units and subsyllabic units and that both types of density jointly determine priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Minimal inhibition concentrations of selected antibiotics for strains of Staphylococcus aureus

Minimal inhibition concentrations (MIC) of gentamycin (Ge), neomycin (Neo), rifampicin (Rif), ampicillin (Amp), lincomycin (Lin), erythromycin (Ery), and streptomycin (STM) were determined by the agar dilution technique using 46, 130, 131, 125, 140, 139 and 142 strains of Staphylococcus aureus, respectively. The strains, selected from the collection of the authors' laboratory, were isolated from mammary gland secretions of cows affected with clinical or subclinical mastitis. The following ranges of MIC (micrograms/ml) were assessed for the antibiotics under study: Ge 0.125-0.50, Neo 0.06-0.50, Rif 0.0039-0.030, Amp 0.015-1.00, Lin 0.25-1.00, Ery 0.06-0.25, STM 0.50-64.0. Modal MIC (micrograms/ml) were as follows; Ery 0.125 (86%), Lin 0.5 (71.4%), Rif 0.007 (68.7%), Ge 0.25 (56.5%), STM 1.00 (54.2%), Neo 0.25 (53.8%), Amp 0.06 (41.6%). The order of efficiency expressed in MIC 90 (micrograms/ml) was as follows: Rif (0.015), Ery (0.125), Ge (0.25), Neo (0.25), Amp (0.5), STM (4.0).     

Synthesis and biological studies on analogs of cyclolinopeptide A with a shortened peptide chain

Continuing our work on the immunosuppressive activity of cyclolinopeptide A (CLA), a cyclic nonapeptide of the sequence: c-(-Leu-Ile-Ile-Leu-Val-Pro-Pro-Phe-Phe), we synthesized a series of 6 linear analogs of CLA, successively shortened at the N-terminus of the peptide chain. Immunosuppressive activity of acetates as well as trifluoroacetates of these peptides was investigated using PFC (humoral immunity) and DTH (cellular immunity) tests. It was found that the immunosuppressive potency of the peptides examined diminishes with shortening of the peptide chain. Octapeptide I with the sequence Ile-Ile-Leu-Val-Pro-Pro-Phe-Phe was found to be the most active of the whole series. The immunosuppressive activity increased again for a tripeptide fragment of CLA of the sequence Pro-Phe-Phe. The immunosuppressive activity of octapeptide probably depends on the suppression of IL-1, IL-6 and TNF production by the cells involved in immune and inflammatory response.     

Electrical characterization and modeling of alternating-currentthin-film electroluminescent devices

Electrical characterization of evaporated ZnS:Mn alternating-current thin-film electroluminescent (ACTFEL) devices is accomplished by capacitance-voltage (C-V) analysis. Interpretation of these C-V characteristics is aided by SPICE modeling and by electrical characterization of an ideal ACTFEL device constructed from discrete components, based on a simple equivalent circuit for the ACTFEL device. Various features of the C -V curve are ascribed to equivalent circuit parameters and associated device physics parameters     

Quasi-optical multiplexer based on reflecting diffraction grating

The article presents results of theoretical and experimental investigation of quasioptical multiplexer based on reflecting diffraction grating. Diffraction losses caused by reflection into mirror harmonic, and by angle divergence of wave beams are calculated. In an experimental multiplexer, wave beams with the frequencies 70 GHz and 79 GHz were mixed with power losses less than 1%.