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F Jentsch

Publications and source records attributed to F Jentsch.

17 recordsLinked to original sources
PubMed2001

What determines whether observers recognize targeted behaviors in modeling displays?

Observational learning is based on a critical assumption that trainees can and do recognize critical modeled behaviors. This assumption has been virtually untested in applied settings. We studied the effects of work experience and instructions on the ability of 59 observers to recognize target behaviors in an observational learning paradigm similar to existing ones. Additionally, we investigated the effects of two key factors that were hypothesized to affect the recognition process in observational learning. The results indicated that only observers who had a minimum of work experience (i.e., intermediate and experienced observers in the study) were able to consistently recognize targeted behaviors. Additionally, recognition was influenced by the level of detail of instructions given to the participants. Finally, characteristics of the modeled behaviors greatly affected recognition: Overall, examples of negative behaviors were better recognized than were positive examples. Behaviors whose consequence was shown were also better recognized than those that were neither reinforced nor punished in the video. The results are discussed in terms of their implications for the design of observational learning as a training strategy in complex and applied social learning situations. The applications of this work include the design of training, and the training of evaluators and observers.

Aviation↗
PubMed1988

[The pH-dependent solubility of heavy metals from sewage sludge of different compositions].

Sludge suspensions of anaerobically digested sewage sludge, limed anaerobically digested sewage sludge, precipitation sludge of the tertiary waste water treatment and limed precipitation sludge were incubated for 8 days with continuous rotation at nine defined pH-values (pH 1, 3-10). After membrane filtration (0.45 micron) solution concentrations of Zn, Cd, Cu, Pb and Cr were determined by atomic absorption spectroscopy. Results show that solubilities of Cd, Zn and Cu depend not only on pH-value but also in a high degree on the sludge type. The solubility is by far the lowest in the anaerobically digested sludge. Most obvious differences can be found for Cd: While the concentrations of soluble Cd in anaerobically digested sludge only increase at pH values lower than pH 4, the solubility of Cd in precipitation sludge and limed sludges already show rapid increases at pH values lower than 7. The solubility of Pb and Cr remains low in all sludges at all pH-values ranging from pH 3 to pH 10. These results show that when judging ecological effects of heavy metals from sewage sludges the physical and chemical composition of these sludges should be considered.

Anaerobiosis↗
PubMed1985

Radiotherapy of non-metastatic ewing sarcoma.

Comparing the radiotherapy data of two groups of patients with non-metastatic Ewing sarcoma, we came to the following conclusions: intensive chemotherapy does not substitute for effective radiotherapy. Irradiation fields should be large enough to include the whole affected bone and the entire extra-osseous compartments, exempting only uninvolved epiphyses. Marginal recurrences are a major risk of the shrinking field technique. Single doses per fraction should be high and the total dose raised to the point of maximal irradiation tolerance of normal tissues.

Adolescent↗
PubMed1983

[Primary lymphedema].

Secondary peripheral lymphedemas (all edemas based on pontine symptoms) are very much more frequent than primary edemas which are either congenital or due to a predisposition. Of the latter, only hereditary (essential) lymphedema and idiopathic lymphedema (lymphedema praecox) play a role in clinical practise with the regard to their incidence. The exceedingly rare hereditary lymphedemas, which differ from the primary noncongenital lymphedemas only with regard to the demonstrated heritability merely have a clinical significance. Thus for example only six such cases occurred amongst our patients in the last 20 years. Most primary lymphedemas occur at the time of puberty with a time span of 10 to 30 years. Primary lymphedemas can also occur within a genuine clinical picture (flat nevi, Recklinghausen disease etc.), so that underlying symptoms must be looked for when they occur.

Adolescent↗
PubMed1980

[On the occurrence of staphylococci and pseudomonas in swimming-pool water (author's transl)].

1. Analyses made at a bath with an additional ozone processing stage showed that the bathers caused a marked bacterial contaminatin on busy days and that this contamination did not originate from the purification plant. 2. This finding and numerous individual analyses of water from various swimming pools yielded a spectrum of 14 micro-organisms, 4 genera being of frequent incidence: bacillus, staphylococcus, pseudomonas and flavobacterium. In general, bacterial contamination exists not only in the pool itself but also after filtering and even subsequent to the addition of chlorine. Staphylococci were found to be particularly invulnerable even to high chlorine contents, which is likely to be attributable to their enclosure in organic material. 5. Tenfold sampling demonstrated that the identification of Staphylococcus aureus in individual samples is unreliable despite its ubiquitous occurrence, probably due to their uneven distribution in the water, while the identification or exclusion of Pseudomonas aeruginosa proves sufficiently dependable even with only individual samples. 4. The general routine analysis of swimming pool water for the presence of staphylococcus aureus appears not justifiable, whilst testing for Pseudomonas aeruginosa appears justifiable, especially for identifying potentially dangerous filter contaminations.

Bacillus↗
PubMed1978

[Chemical parameters in coastal waters in correlation with microbiological parameters (author's transl)].

Nearly 4600 samples of coastal water from the Baltic Sea were characterized by microbiological parameters as well as by pH, ammonium, nitrite, nitrate, phosphate, and oxidizability by permanganate. Correlation of E. coli with chemical parameters varies strongly according to parameter, region, and season. Sanitary assessments can only be based on microbiological findings.--As regards eutrophication, we should expect special and more comprehensive chemical test programmes to give us substantial knowledge, whereas chemical tests after the EC guidelines for bathing waters along the Baltic Sea coast would mean considerable work and costs without getting any new results.

Escherichia coli↗
PubMed1977

[Experience gained with ozone/activated-charcoal treatment of swimming-pools filled with sea water (author's transl)].

An ozone/activated charcoal stage in the water treatment also lends itself extremely well to improving the quality of sea water in swimming pools. This improvement is typically reflected in the low content of organic substances and nitrogen compounds (ammonia, urea) and, as a result, in the high redox potentials in the swimming-pool water which are even likely to bring about a rapid inactivation of the viri. A small percentage of the bromide in the sea water is oxidised to free bromide which passes through the activated charcoal filter, counteracts the growth of germs, keeps the filtrate largely free from germs and contributes to the disinfection of the swimming pool.

Ammonia↗
PubMed1977

[Examination of the growth of pathogenic organisms on the elastic joints made of plastic material in swimming baths (author's transl)].

Roughly three months after a swimming bath had been put into operation a growth was observed on the permanently elastic joints made of plastic material at the bottom of the pool. Samples were taken and examined and bacteria, fungi, green algae as well as many monocellular organisms were found. The repeated identification of a pathogenic dermatophyte and of P. aeruginosa was of hygienic significance.

Chlorophyta↗
PubMed1976

[Results of radiotherapy of bronchial carcinoma (author's transl)].

In a joint retrospective study by 17 radiotherapy clinics in German-speaking countries the results of treatment of bronchial carcinoma after radiotherapy were analysed in 7503 cases. The age peak was between the 60th and 70th year. Squamous-cell carcinoma was the most frequent histological type, followed by anaplastic carcinoma, with adenocarcinoma being rare. There was a high proportion of histologically not clearly identified cases (27% in central and 35% in peripheral carcinomas). Survival rate at one year was 31% for central (3662 patients) and peripheral (961 patients) tumours, but only 2% at five years. Prognostically there was no difference between histological types and kind of radiotherapy or technique, but total dose affected survival rate. At a total dose of less than 5000 rd the survival rate at five years was minimal. The prognosis of combined surgical and radiotherapeutic measures was slightly better than with a radiotherapy alone, but results were unpredictable for the individual case. It is concluded that radiotherapy aiming at cure should be used in imoperable bronchial carcinoma if the tumour state and general condition of the patient appear to make a cure possible. But if this is not the case, radiotherapy should be used only palliatively, i.e. only to ameliorate symptoms.

Adenocarcinoma↗