On the Role of Mechanics in Chronic Lung Disease.

Progressive airflow obstruction is a classical hallmark of chronic lung disease, affecting more than one fourth of the adult population. As the disease progresses, the inner layer of the airway wall grows, folds inwards, and narrows the lumen. The critical failure conditions for airway folding have been studied intensely for idealized circular cross-sections. However, the role of airway branching during this process is unknown. Here, we show that the geometry of the bronchial tree plays a crucial role in chronic airway obstruction and that critical failure conditions vary significantly along a branching airway segment. We perform systematic parametric studies for varying airway cross-sections using a computational model for mucosal thickening based on the theory of finite growth. Our simulations indicate that smaller airways are at a higher risk of narrowing than larger airways and that regions away from a branch narrow more drastically than regions close to a branch. These results agree with clinical observations and could help explain the underlying mechanisms of progressive airway obstruction. Understanding growth-induced instabilities in constrained geometries has immediate biomedical applications beyond asthma and chronic bronchitis in the diagnostics and treatment of chronic gastritis, obstructive sleep apnea and breast cancer

Giving or Taking: The Role of Dispositional Power Motivation and Positive Affect in Profit Maximization?

Socio-economic decisions are commonly explained by rational cost vs. benefit considerations, whereas person variables have not usually been considered. The present study aims at investigating the degree to which dispositional power motivation and affective states predict socio-economic decisions. The power motive was assessed both indirectly and directly using a TAT-like picture test and a power motive self-report, respectively. After nine months, 62 students completed an affect rating and performed on a money allocation task (Social Values Questionnaire). We hypothesized and confirmed that dispositional power should be associated with a tendency to maximize one’s profit but to care less about another party’s profit. Additionally, positive affect showed effects in the same direction. The results are discussed with respect to a motivational approach explaining socio-economic behaviour.economic decision-making, rational choice theory, personality, implicit power motive, positive affect, operant motive test

Microparticles enhance natural product formation in native and metabolically engineered actinobacteria through accelerated morphological development

Actinobacteria, especially the genus Streptomyces, provide a plethora of bioactive natural products. Over the last years, the ubiquitous use of antibiotics resulted in the increasing threat of resistant bacteria, explaining the intense research efforts nowadays to identify new bioactive substances and to improve production. Here, we studied the use of inorganic talc microparticles to enhance natural product formation in actinobacteria. Addition of talc to S. albus J1074/R2 tripled pamamycin production up to 50 mg L-1, yielded a specific production spectrum of the derivatives, and strongly reduced pellet size. Systems biology analyses demonstrated the underlying mechanism of the production shift and revealed a globally reprogrammed gene expression. Supplied to S. lividans TK24 DG2-Km-P41hyg+, talc led to increased production of 109 mg L-1 of combined bottromycin A2, a promising antibiotic for drug development. Talc presence resulted in an increased production efficiency by rebalancing the cluster expression and caused an accelerated morphogenesis. Finally, we miniaturized the setup and examined the production of twelve natural products from different actinobacterial genera. In 75% of the studied cases, talc enhanced natural product formation and was even crucial for teicoplanin production. Due to the effectiveness and simplicity, morphology engineering of actinobacteria using talc microparticles appears as a promising approach for future applications.Actinobacteria, insbesondere die Gattung Streptomyces, liefern eine Vielzahl an bioaktiven Naturstoffen. In den letzten Jahren führte der verstärkte Einsatz von Antibiotika zu einer zunehmenden Bedrohung durch resistente Bakterien, was die heutige intensive Forschung nach neuen bioaktiven Substanzen und deren Produktionsoptimierung begründet. Hier untersuchten wir die Verwendung von anorganischen Talk-Mikropartikeln, um die Naturstoffbildung in Actinobacteria zu steigern. Die Zugabe der Mikropartikel zu S. albus J1074/R2 verdreifachte die Pamamycin-Produktion auf bis zu 50 mg L-1, ergab ein spezifisches Spektrum der Derivate und reduzierte deutlich die Pelletgröße. Systembiologische Analysen offenbarten die Ursache der Produktverschiebung sowie eine global umprogrammierte Genexpression. Addition von Talk zu S. lividans TK24 DG2-Km-P41hyg+, führte zu einer beschleunigten Morphogenese und zu einer gesteigerten Produktion von 109 mg L-1 Bottromycin A2, indem es die Clusterexpression neu ausbalancierte. Abschließend miniaturisierten wir das Setup und untersuchten die Produktion von zwölf Naturstoffen aus verschiedenen Actinobacteria-Gattungen. In 75% der untersuchten Fälle förderte die Zufuhr von Talk die Bildung des Naturprodukts und war sogar entscheidend für die Produktion von Teicoplanin. Aufgrund seiner Effektivität und Einfachheit erscheint Morphologie-Engineering von Actinobacteria mittels Talk-Mikropartikeln als vielversprechender Ansatz für zukünftige Anwendungen

Refining the Experimental Extraction of the Number of Independent Samples in a Mode-Stirred Reverberation Chamber

We investigate the number of independent samples in a chaotic reverberation chamber. Its evaluation as defined by the IEC standard can be made more precise when using not the index of the first value larger then the correlation length but using the value obtained by a linear interpolation instead. The results are validated by a juxtaposition with values from a measurement using a high stirrer-angle resolution. A comparison with estimates known from the literature validates our findings. An alternative approach using the local maxima of the parametric dependence of the transmission is presented in order to show the applicability of the extracted correlation length over a large range of frequencies.Comment: 7 pages, 7 figure

Personality across the lifespan. Exploring measurement invariance of a short big five inventory from ages 11 to 84

Personality is a relevant predictor for important life outcomes across the entire lifespan. Although previous studies have suggested the comparability of the measurement of the Big Five personality traits across adulthood, the generalizability to childhood is largely unknown. The present study investigated the structure of the Big Five personality traits assessed with the Big Five Inventory-SOEP Version (BFI-S; SOEP = Socio-Economic Panel) across a broad age range spanning 11-84 years. We used two samples of N = 1,090 children (52% female, Mage = 11.87) and N = 18,789 adults (53% female, Mage = 51.09), estimating a multigroup CFA analysis across four age groups (late childhood: 11-14 years; early adulthood: 17-30 years; middle adulthood: 31-60 years; late adulthood: 61-84 years). Our results indicated the comparability of the personality trait metric in terms of general factor structure, loading patterns, and the majority of intercepts across all age groups. Therefore, the findings suggest both a reliable assessment of the Big Five personality traits with the BFI-S even in late childhood and a vastly comparable metric across age groups. (DIPF/Orig.