Die wissenschaftlichen Grundlagen der Pulvermetallurgie

Bei der klassischen Metallurgie sind die wesentlichsten Etappen bei der Herstellung von Metallgegenstanden die folgenden: a) Schmelzen des Metalls, b) Giessen in Formen, c) Nachbehandlung. Bei der Pulvermetallurgie muss das Metall a) in ein Pulver ubergefilhrt werden, welches b) in die gewunschte Form gepresst wird, worauf c) durch Erhitzen auf eine Temperatur, die unterhalb des Schmelzpunktes liegt, der Korper sich infolge des Zusammensinterns, verfestigt

Die wissenschaftlichen Grundlagen der Pulvermetallurgie

Bei der klassischen Metallurgie sind die wesentlichsten Etappen bei der Herstellung von Metallgegenstanden die folgenden: a) Schmelzen des Metalls, b) Giessen in Formen, c) Nachbehandlung. Bei der Pulvermetallurgie muss das Metall a) in ein Pulver ubergefilhrt werden, welches b) in die gewunschte Form gepresst wird, worauf c) durch Erhitzen auf eine Temperatur, die unterhalb des Schmelzpunktes liegt, der Korper sich infolge des Zusammensinterns, verfestigt

The Severity of Human Peri-Implantitis Lesions Correlates with the Level of Submucosal Microbial Dysbiosis

AIM To cross-sectionally analyse the submucosal microbiome of peri-implantitis (PI) lesions at different severity levels. MATERIALS AND METHODS Microbial signatures of 45 submucosal plaque samples from untreated PI lesions obtained from 30 non-smoking, systemically healthy subjects were assessed by 16s sequencing. Linear mixed models were used to identify taxa with differential abundance by probing depth, after correction for age, gender, and multiple samples per subject. Network analyses were performed to identify groups of taxa with mutual occurrence or exclusion. Subsequently, the effects of peri-implant probing depth on submucosal microbial dysbiosis were calculated using the microbial dysbiosis index. RESULTS In total, we identified 337 different taxa in the submucosal microbiome of PI. Total abundance of 12 taxa correlated significantly with increasing probing depth; a significant relationship with lower probing depth was found for 16 taxa. Network analysis identified two mutually exclusive complexes associated with shallow pockets and deeper pockets, respectively. Deeper peri-implant pockets were associated with significantly increased dysbiosis. CONCLUSION Increases in peri-implant pocket depth are associated with substantial changes in the submucosal microbiome and increasing levels of dysbiosis

Large-scale replication study reveals a limit on probabilistic prediction in language comprehension

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment (‘cloze’). In our direct replication study spanning 9 laboratories (N=334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words