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H Steiger

Publications and source records attributed to H Steiger.

At least 55 records · Page 3Linked to original sources
PubMed1982

Negating the effects of binaural cues: competition between auditory streaming and contralateral induction.

When a pair of monaural pure tones, A and B, are repeatedly alternated in one ear, with noise bursts presented in synchrony with B in the other ear, the noise sometimes delateralizes B. This is presumably a case of Warren and Bashford's (1976) contralateral induction effect. However, the present experiment shows that the degree of contralateral induction is proportional to the separation in frequency between A and B. It was also found that the degree to which the noise bursts influenced B's timbre was proportional to the separation in frequency between A and B. The combined results suggest that cues that govern the sequential organization of sounds influence the use of binaural cues not only during the assignment of position to auditory events but during the assignment of timbre.

Acoustic Stimulation↗
PubMed1981

Genetic analysis of prophage effects on heteroimmune superinfection in Serratia marcescens.

Plaque formation of phage kappa on Serratia marcescens strain HY normally depends on the presence of either a psi or y prophage in the indicator bacteria. Bacterial ink mutants allowing kappa growth in the absence of either prophage were isolated from the doubly cured strain HY (psi, y)--. By means of a kappa mutant, named gdy, an active participation of kappa in antagonizing inhibition of its own growth on HY (psi, y)-- was demonstrated. The gdy mutation is closely linked to gene cIII coding for the kappa repressor. The prophages psi and y enable kappa to grow undisturbed probably by modifying the kappa DNA during replication in such a way that it is not susceptible to the ink+ effect. Whereas kappa grown on HY (psi, y)--ink-- gave only rare productive infections of HY (kappa, y)--, psi and y grown on the same strain were fully infective. The interference exerted by a kappa prophage on vegetative propagation of y is based upon a multi-component mechanism, the interference being removed, or diminished by mutations residing either inside or outside of the kappa prophage. The responsive phage gene iny+ is dominant over its mutant allele iny--; hence it codes for a diffusible product. Both on the vegetative and the prophage genome iny is located near gene lI responsible for lysogenic conversion of bacteria to non-adsorption of kappa. The restriction-modification system of HY is not involved in the growth inhibition of kappa by HY (psi, y)--. Contrary to the other phages used in this work y is refractory to restriction.

Bacteriophages↗
PubMed1980

[An investigation on the mortality during a smog situation in western Ruhrgebiet on the 17. January 1979 (author's transl)].

A smog-warning of the first degree was announced on the 19th January 1979 for the first time after the institution of the so called Smog-decree in Northrhine-Westphalia. This warning was calceled after a few hours, already. The mortality in the relevant areas did not increase during this period. The adequacy of the 1st stage of the smog-warning was thus confirmed. This stage signifies a prewarning, which indicates a situation with no expected harmful effects of air-pollution on the population.

Emergencies↗
PubMed1975

Different types of thermoconditional clear plaque-mutants and prophage induction by heat or cold of Serratia phage kappa.

Phage kappa of Seratia marcescens was treated with different mutagens to induce thermoconditional clear plaque-mutants. 176 mutants obtained were analysed by crosses and found to be located in clear plaque-region III. Two types resembling the mutants t2 and t1 of phage lambda were identified. Lysogens for the mutant 126 can be induced by heat and even by cold whereas they are scarcely inducible by uv. Nevertheless, a 126 prophage like a uv inducible ct 163 prophage can be sensitized to thermoinduction by short preirradiation if the cells are incubated for 30 to 45 min between uv exposure and heating. With ct 163 this time corresponds to the minimum extension of latent period after uv induction compared with infection at low moi. A mutant of clear plaque-region II, c154, shows an inverted thermoconditional behaviour forming clear plaques at 30 degrees C and turbid plaques due to lysogenization at 37 degrees C.

Journal Article↗