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The temperature dependent surface impedance Zs(T)of single-crystalline YBa2Cu3O7-x(YBCO) was analyzed within the two-fluid model in terms of the fraction of paired charge carriers, fs(T), and of the quasiparticle scattering time. The usual approach was extended by considering a temperature dependent effective quasiparticle mass m*(T), which results from a strong electron-phonon interaction. This effect must not be neglected in the description of high-temperature superconductors due to the large ratio of Tcto the Debye temperature TD. The temperature dependence of the penetration depth, of high-quality YBCO crystals and films could be described with an electron-phonon coupling constant, and using fs(T) = 1- (T/Tc)2.8as an approximation of the BCS theory. Different trial phonon spectra were encountered in terms of their ability to reproduce the -data. The scattering time was described by the Bloch-Grüneisen formalism with TD=460 K. Assuming an Einstein spectrum with, a residual resistivity and a fraction of unpaired quasiparticles at T= 0 Kyielded a surprisingly good agreement of the model with Zs(T)-data measured at 87 GHz with a high-quality epitaxial YBCO film between T=4 Kand Tc. While an exact reproduction of the surface impedance asks for a rigorous theoretical computation, our analysis demonstrates that strong electron-phonon coupling is relevant for discussing the unconventional transport properties of YBCO.

Quality of recovery after anaesthesia is an important measure of the early postoperative health status of patients. We attempted to develop a valid, reliable and responsive measure of quality of recovery after anaesthesia and surgery. We studied 160 patients and asked them to rate postoperative recovery using three methods: a 100-mm visual analogue scale (VAS), a nine-item questionnaire and a 50-item questionnaire; the questionnaires were repeated later on the same day. From these results, we developed a 40-item questionnaire as a measure of quality of recovery (QoR-40; maximum score 200). We found good convergent validity between QoR-40 and VAS (r = 0.68, P < 0.001). Construct validity was supported by a negative correlation with duration of hospital stay (rho = -0.24, P < 0.001) and a lower mean QoR-40 score in women (162 (SD 26)) compared with men (173 (17)) (P = 0.002). There was also good test-retest reliability (intra-class ri = 0.92, P < 0.001), internal consistency (Cronbach's alpha = 0.93, P < 0.001) and split-half coefficient (alpha = 0.83, P < 0.001). The standardized response mean, a measure of responsiveness, was 0.65. The QoR-40 was completed in less than 6.3 (4.9) min. We believe that the QoR-40 is a good objective measure of quality of recovery after anaesthesia and surgery. It would be a useful end-point in perioperative clinical studies.

Surface impedance data at 19 and 87 GHz of high-quality epitaxial YBCO films on different substrates are compared with data for Nb3Sn films on sapphire in terms of pair and quasiparticle (qp) transport. Surface resistance Rsand penetration depth λ of YBCO are strongly affected by temperature dependent qp scattering, which is depressed in films with enhanced lattice strain. All films showed a comparable residual resistance Rres(19 GHz)∼90 μΩ constituting a qp reservoir which is likely to be caused by the electronic configuration and by impurities. Subtracting Rresfrom Rs(T)revealed activated behavior with a reduced energy gap Δ0/kBTc∼0.9 for a film on sapphire, but power-law behavior for the other films. The penetration depth did not reveal power-law dependences at T≤0.5 ·Tc, but was consistent with a reduced energy gap of 0.45 for a film on MgO. The increase of λ(T) at T≥0.5 · Tcwas related to qp scattering, which also caused an extremal conductivity σ1(T). A shoulder in λ(T) at T=(0.6–0.7) · Tcconfirmed evidence for the existence of two superconducting bands. The magnetic-field induced recovery of λ(B) of various YBCO films hinted for an important role of magnetic scattering. The results are in contradiction to a d-wave symmetry of the order parameter, at least for the chain band.

Abstract: An anomalous magnetic field-effect has been observed in the microwave surface impedance of epitaxial YBa2Cu3O7−x films on LaAlo3 substrates. The application of dc and microwave magnetic fields up to 20 mT caused a significant decrease of microwave surface reactanceX s (≤3%) and resistanceR s (≤20%) at 8.5 GHz, 77 K and at 87 GHz, 4.2 K. The field effects onX s andR s s were found to correlate within the framework of the two-fluid model. The observed effect is attributed to the presence of magnetic impurities in the superconducting films, giving rise to pair breaking. Alignment of the impurity spins suppresses the spin-flip scattering rate and, as a result, leads to a recovery of microwave superconductivity.

The surface impedance of two 350nm thick YBCO films was measured for temperatures between 4.2K and 150K in a copper cavity at 87 GHz. Both films, one grown by electron beam evaporation on MgO, the other one by high oxygen-pressure dc sputtering from a stoichiometric target on LaAlO3, provide critical temperatures of about 91K, low residual surface resistances of Rs(4.2K) < 1mO and low specific resistivities in the normal state of ?(100K) < 85µOcm. The experimental data obtained on these two films are compared to a d-wave model of superconductivity which incorporates elastic and inelastic scattering. Good agreement between theory and the experimental results for both the surface resistance and the penetration depth in the whole temperature range is achieved for scattering phase shifts near 0.4p and order parameter amplitudes in the range of 2?0(0)/kBTc = 6.0 – 7.5 without subtracting an extrinsic residual surface resistance.

Abstract: The conditions for the design of compact high-power HTS filters are deduced from basic considerations, and related to the microwave properties of the HTS films and the substrates. Potential mechanisms limiting the linear microwave response of HTS films are analyzed systematically. Magnetic and thermal field breakdowns are found to confine the power handling capability to comparable field levels. While magnetic limitation is related to flux penetration at the lower critical field Bc1, thermally induced quenches occur dependent on the presence of defects and on the thermal conductivity of the substrate. The detrimental role of film inhomogeneities for the linear microwave response is confirmed experimentally for microwave fields at 19 GHz and for dc fields at 87 GHz.

Abstract: An anomalous magnetic field-effect has been observed in the microwave surface impedance of epitaxial YBa2Cu3O7−x films on LaAlo3 substrates. The application of dc and microwave magnetic fields up to 20 mT caused a significant decrease of microwave surface reactanceX s (≤3%) and resistanceR s (≤20%) at 8.5 GHz, 77 K and at 87 GHz, 4.2 K. The field effects onX s andR s s were found to correlate within the framework of the two-fluid model. The observed effect is attributed to the presence of magnetic impurities in the superconducting films, giving rise to pair breaking. Alignment of the impurity spins suppresses the spin-flip scattering rate and, as a result, leads to a recovery of microwave superconductivity.

Cell-mediated immunity to herpes simplex virus type 1 (HSV-1) was assessed by a lymphocytotoxicity 51-Cr-release microassay procedure, using the MA-160 human prostatic adenoma cell line chronically infected with HSV-1 and its parent cell line as control. The specific immune release mean plus or minus standard deviation for nine asymptomatic patients with recurrent HSV-1 infections was 13.7 plus or minus 8.1%, compared to 28.9 plus or minus 8.4% in seven normal seropositive controls (P is less than 0.01). In four additional patients studied serially, the cell-mediated immunity was significantly increased during the recrudescence of herpetic infection, with a mean specific immune release value of 51.7 plus or minus 27.8%, compared to 8.7 plus or minus 1.5% during the convalescent period 2 to 10 weeks later (P is less than 0.05). These findings suggest that patients with recurrent HSV-1 infections have vigorous cellular immune responses during the acute phase but a specific impairment of cell-mediated immunity during the quiescent period, which may in part account for their susceptibility to recurrent herpetic infections.

We used a dielectric resonator technique for highly sensitive measurements of the temperature dependence of the microwave surface resistanceRsof 1×1 cm2 superconducting films at 18.7 GHz. It consists of a sapphire disc positioned on the film under investigation within a copper cavity which is acting as a radiation shield. In the TE01d oscillation mode the highly reproducible quality factor of about 105 results in a sensitivity of ±50µO forRsmeasurements. The temperature dependence ofRscan be measured up to values as high as 1 O. We have investigated several YBa2Cu3O7 thin films prepared by high oxygen pressure d.c. sputtering on LaAlO3 and NdGaO3. Our best films exhibit a pronounced nonlinear behavior of the d.c. resistivity?(T) with?(300K)/?(100K) values of about 3.7. Those films show, besides the initial fall-off just belowTc, a further strong decrease ofRsat low temperatures. This was observed both at 18.7 GHz and 87 GHz, as measured by a conventional cavity end plate replacement technique. ForT«Tc/2 these films exhibit an exp (-aTc/T) dependence ofRswitha-values around 0.4. These observations may be explained by a superconducting energy gap with 2?/kTc˜0.8 for charge carriers localized in the CuO chains for YBa2Cu3O7.

The conditions for the design of compact high-power HTS filters are deduced from basic considerations, and related to the microwave properties of the HTS films and the substrates. Potential mechanisms limiting the linear microwave response of HTS films are analyzed systematically. Magnetic and thermal field breakdowns are found to confine the power handling capability to comparable field levels. While magnetic limitation is related to flux penetration at the lower critical field Bc1, thermally induced quenches occur dependent on the presence of defects and on the thermal conductivity of the substrate. The detrimental role of film inhomogeneities for the linear microwave response is confirmed experimentally for microwave fields at 19 GHz and for dc fields at 87 GHz.

Rubella complement-fixing (CF) antigen and infectious virus were produced continuously and concurrently for as long as 63 days in suspension cultures of BHK-21 cells prepared from uncloned monolayer stock cultures. CF titers ranged from 1:4 to 1:32, and the peak infectivity titer was greater than 8.0 (TCID50log10) per ml. Suspension cultures could be recultivated after prolonged storage in liquid nitrogen. The resulting monolayer or suspension cultures also produced CF antigen. Suspension cultures provide an effective system for the long-term continuous and concurrent production of rubella virus diagnostic reagents.

Zusammenfassung Cytogenetische Befunde zum Nachweis oder Ausschluß eines Ph1-Chromosoms und Untersuchungen zu dem cytologischen Merkmal der alkalischen Leukocytenphosphatase (ALP) werden in den Vordergrund einer Analyse von 4 Fällen einer chronischen Myelose gestellt. In einem Fall einer CML mit lang anhaltender aplastischer Phase wurde im Knochenmark eine Ph1-positive Stammlinie neben Ph1-negativen Stammlinien mit Extra-C-Chromosomen nachgewiesen; der ALP-Index war extrem hoch. Ein bis kurz vor dem Tod aleukämisch verlaufender Fall einer chronischen Myelose war Ph1-negativ und wies einen ALP-Defekt auf. Von 2 Fällen einer CML des späten Kindesalters war einer Ph1-positiv, der andere Ph1-negativ.

A new 51Cr-release microassay is described for the measurement of cell-mediated immunity to cytomegalovirus, using cryopreserved target cells acutely infected with cytomegalovirus.