Radiation effects on silicon Quarterly progress report, Oct. 1 - Dec. 31, 1966

Transient and quiescent electric conductivity in silicon after electron irradiation at room temperatur

Ceftazidime: pharmacokinetics in young volunteers versus elderly patients and therapeutic efficacy with complicated urinary tract infections

Thirty-six urological patients (21 male, 15 female) aged 21 to 83 years with complicated and/or hospital-acquired urinary tract infections due to sensitive bacteria were treated with ceftazidime intravenously with a daily dose of 2 g bd over 5 to 17 days. Twenty-seven patients were followed for 1 to 4 weeks after therapy. Cure was observed in 41%, reinfection in 33% and relapse in 26% of the patients. Eradication of the original pathogen occurred in 74%. Five patients showed minor side effects: diarrhoea (2), nausea (1), rash (1), headache (1). No signs of renal, hepatic or haematological toxicity were observed. A pharmacokinetic study was performed in 13 elderly patients aged 63 to 83 years on day 1 of treatment and in 6 volunteers aged 24 to 32 years following administration of 2 g of ceftazidime as short intravenous infusion. The mean serum half life in 12 patients 2.9 h significantly higher than in volunteers (1.75 h). Serum concentrations in patients on day 7 of treatment, however, showed no accumulation when treated with a dosage of 2 g bd

Radiation effects on silicon Sixth quarterly progress report, Apr. 1 - Jun. 30, 1966

Radiation effects on high purity n-type silicon solar cell

Radiation effects on silicon Summary report 1 Nov. 1965 - 20 Apr. 1967

Radiation-induced displacement effects measured in n and p type, low and high resistivity silico

Pharmacokinetics, in-vitro activity, therapeutic efficacy and clinical safety of aztreonam vs. cefotaxime in the treatment of complicated urinary tract infections

The minimal inhibitory concentrations (MICs) of aztreonam and cefotaxime were determined against 400 isolates from urological in-patients with complicated and/or hospital acquired urinary tract infections (UTI). Against the Gram-negative rods the activities of both antibiotics were comparable except for higher activity of aztreonam against Pseudomonas aeruginosa. The pharmacokinetic study in nine elderly patients showed a prolonged plasma half life of aztreonam (2.7 h) as compared to younger volunteers (1.6-1.9 h). In a prospective randomized study 39 urological patients with complicated and/or hospital acquired UTI were treated with 1 g aztreonam or cefotaxime iv twice daily for 4 to 15 days. Cure was obtained in 5 out of 18 patients in the aztreonam and 7 out of 20 patients in the cefotaxime group. There were 3 superinfections, 7 relapses and 3 reinfections in the aztreonam group and 1 failure, 1 superinfection, 6 relapses and 5 reinfections in the cefotaxime group. There was no significant difference in therapeutic efficacy between the two antibiotics. Both antibiotics were tolerated well and seem to be equally effective in the treatment of complicated UTI caused by sensitive organisms

High-performance liquid chromatography analysis of mezlocillin, piperacillin, their degradation products, and of ioxitalamic acid in plasma and urine of healthy volunteers

In plasma and urine of 10 healthy volunteers after intravenous administration of 4 g mezlocillin and piperacillin, respectively, the parent compounds as well as degradation products were assayed by high-performance liquid chromatography. Ioxitalamic acid, a renal contrast medium, was administered simultaneously, in order to measure the glomerular filtration rate, and to control the collection of 24-h urine. As metabolite of mezlocillin the corresponding penicilloic acid only was found, whereas in the case of piperacillin a further degradation product was observed. Half of the doses given was recovered in the urine as unchanged drugs, and in addition 5-10% as metabolites. No differences were found in the pharmacokinetic behaviour of both antibiotics

Type-II Bose-Mott insulators

The Mott insulating state formed from bosons is ubiquitous in solid He-4, cold atom systems, Josephson junction networks and perhaps underdoped high-Tc superconductors. We predict that close to the quantum phase transition to the superconducting state the Mott insulator is not at all as featureless as is commonly believed. In three dimensions there is a phase transition to a low temperature state where, under influence of an external current, a superconducting state consisting of a regular array of 'wires' that each carry a quantized flux of supercurrent is realized. This prediction of the "type-II Mott insulator" follows from a field theoretical weak-strong duality, showing that this 'current lattice' is the dual of the famous Abrikosov lattice of magnetic fluxes in normal superconductors. We argue that this can be exploited to investigate experimentally whether preformed Cooper pairs exist in high-Tc superconductors.Comment: RevTeX, 17 pages, 6 figures, published versio

Surface Acoustic Wave induced Transport in a Double Quantum Dot

We report on non-adiabatic transport through a double quantum dot under irradiation of surface acoustic waves generated on-chip. At low excitation powers, absorption and emission of single and multiple phonons is observed. At higher power, sequential phonon assisted tunneling processes excite the double dot in a highly non-equilibrium state. The present system is attractive for studying electron-phonon interaction with piezoelectric coupling.Comment: 4 pages, 3 figure

Single-shot readout of electron spin states in a quantum dot using spin-dependent tunnel rates

We present a method for reading out the spin state of electrons in a quantum dot that is robust against charge noise and can be used even when the electron temperature exceeds the energy splitting between the states. The spin states are first correlated to different charge states using a spin dependence of the tunnel rates. A subsequent fast measurement of the charge on the dot then reveals the original spin state. We experimentally demonstrate the method by performing read-out of the two-electron spin states, achieving a single-shot visibility of more than 80%. We find very long triplet-to-singlet relaxation times (up to several milliseconds), with a strong dependence on in-plane magnetic field.Comment: 4 pages, 4 figure