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Additive manufacturing techniques such as vat photopolymerization have laid the foundation for impressive advances in the 3D structuring of ceramic materials. However, simultaneous structuring of these complex‐shaped ceramic objects on the sub‐µm scale, an essential feature for a wide range of applications in separation, energy conversion and storage, adsorption or sensing, has remained a tremendous challenge. This study demonstrates how complex‐shaped polymer‐derived SiOC ceramics exhibiting hierarchical porosity ranging from the sub‐µm‐ to the millimeter‐range can be generated by combining vat photopolymerization with photopolymerization‐induced phase separation using preceramic polymer‐based phase‐separating resins. In addition to allowing single‐step, multi‐level structural control, this new processing concept allows for the chemical modification of the 3D‐printable, phase‐separating preceramic polymer resins using organometallic compounds, including the possibility to generate functional metal nanoparticles in situ during the polymer‐to‐ceramic conversion. In this manner, a chemical toolbox is provided, facilitating the introduction of Ni, Co, Mo, or La into the hierarchically structured SiOC matrix. The versatile applicability of this new materials design approach is demonstrated by employing complex‐shaped, hierarchically porous monoliths containing in situ generated Ni nanoparticles as heterogeneous catalysts for CO2 methanation, with a profound increase in catalyst performance attained by oxidative post‐treatment of the metal‐ceramic hybrid material. [ABSTRACT FROM AUTHOR]

Alloying rare earth elements into aluminum nitride (AlN) thin films to increase the piezoelectric response has gained a lot of attention in the past few years. Many rare earth elements are investigated in which scandium alloying resulted in the highest piezoelectric response for AlN. At the same time, researchers have also theoretically explored yttrium alloying as a feasible and economical alternative to scandium. Herein, for the first time, experimentally, the increase of the piezoelectric response of sputter-deposited YxAl1-xN thin films as a function of increasing yttrium concentration as predicted by density functional theory calculations is demonstrated. Using differently manufactured targets, YxAl1-xN thin films with four different yttrium alloying concentrations (9, 12, 15, and 20 at%). are synthesized. Detailed thin-film analysis is carried out and the highest value of d33 measured is 12 pC N-1 for Y0.2Al0.8N, which is a 250% increase compared to pure AlN. Even more, the Young's modulus decreases with increasing yttrium concentration in excellent agreement with theoretical predictions. Finally, Y0.15Al0.85N and Y0.2Al0.8N layers show high crystalline stability in pure oxygen environment up to 800 °C, demonstrating high oxidation resistance even under harsh environmental conditions. [ABSTRACT FROM AUTHOR]

Alloying transition metals into aluminum nitride (AlN) has surged over the past decade to increase the piezoelectric performance of AlN for microelectromechanical systems (MEMS) applications. So far, the highest piezoelectric coefficients have been achieved by alloying scandium into AlN. But, most recently published studies have theoretically predicted by ab‐initio calculations that yttrium can also be a promising and less expensive alternative to scandium. This paper focuses on the impact of an AlN seed layer on the growth and piezoelectric properties of sputter‐deposited, polycrystalline Y0.15Al0.85N thin films on a silicon substrate. For the first time, the increase in piezoelectric performance of YxAl1−xN (x = 15%) thin films with a d33 of ≈7.85 pC N−1 due to this seed layer approach is presented, thus reaching in good agreement theoretical predictions. Furthermore, for the first time, the crystalline stability of Y0.15Al0.85N layers in a pure oxygen environment up to 1200 °C is reported, demonstrating a high oxygen resistance up to 800 °C even in this harsh environment. Detailed thin film analysis is done with various techniques such as X‐ray diffraction, atomic force microscopy, nano‐indentation, and high‐resolution transmission electron microscopy and correlated with piezoelectric coefficient measurements. [ABSTRACT FROM AUTHOR]

A bimetallic Cu/Cu51Zr14 precatalyst, activated in situ, for hydrogen generation from methanol and water provides very high CO2 selectivity (>99.9 %) and high H2 yields. Referenced to the geometric surface area of our model surface, higher activity of at least one order of magnitude was observed in comparison to supported Cu/ZrO2 and Cu/ZnO/ZrO2 catalysts. Evolution of structural activation monitored by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and electron microscopy indicates transformation of the bimetallic Cu/Cu51Zr14 precatalyst into an active, selective, and self-stabilizing state with coexistence of dispersed Cu and partially hydroxylated tetragonal ZrO2. The outstanding performance is assigned to the presence of a high interface-site concentration following in situ decomposition of the intermetallic compound. These active sites result from the cooperation of Cu, responsible for methanol activation, and tetragonal ZrO2, which activates the water by surface hydroxylation. [ABSTRACT FROM AUTHOR]

Mundt T, Polzer I, Samietz S, Grabe HJ, Dören M, Schwarz S, Kocher T, Biffar R, Schwahn C. Gender-dependent associations between socioeconomic status and tooth loss in working age people in the Study of Health in Pomerania (SHIP), Germany. Community Dent Oral Epidemiol 2011; 39: 398-408. © 2011 John Wiley & Sons A/ S Abstract - Objectives: Individual impact and the effect magnitude of socioeconomic key indicators (income, education and occupation) and of gender on oral health are ambiguous. In primary analyses of cross-sectional data among participants of the Study of Health in Pomerania (north-east Germany), women with low school education and low income were at highest risk for missing teeth, whereas being single was a risk indicator for missing teeth in men. Using the 5-year follow-up of this study, we aimed at verifying these findings and at investigating the gender-dependent impact of key socioeconomic indicators on tooth loss. Methods: The longitudinal data originate from 1971 subjects (1062 women) aged 25-59 enrolled from 1997 to 2001 and again from 2002 to 2006. The effects of marital status, household income, school education and occupational prestige for tooth loss were examined by gender using negative binomial regression analyses. Results: Low education and low income were moderately [relative risks (RR) between 1.6 and 2.0] associated with tooth loss among both women and men, whereas occupational prestige was not. After multiple imputations of missing data, less-educated women with lower income exhibited the highest risk of tooth loss [RR = 3.1; 95% confidence interval (CI) = 1.7-5.5 for <10 years of school education and the lowest income tertile] and tooth loss was more likely in single men (RR = 1.5; 95% CI = 1.0-2.2) than in single women (RR = 0.9; 95% CI = 0.6-1.3). Conclusions: The primary cross-sectional results were partly confirmed. Socioeconomic factors help to explain differences in tooth loss, although the causal pathways are speculative. To improve dental health, the policies should target not only the individual, e.g. oral health promotion, but also an entire population by better education and higher wage employment. [ABSTRACT FROM AUTHOR]

The precipitation of AlN is investigated in the austenite region of ultra low carbon steel. The evolution of the size and the morphology of AlN precipitates are studied by transmission electron microscopy (TEM) after isothermal annealing for different times at temperatures of 950 °C and 1050 °C. Various different morphologies are observed, including cuboids, large plates as well as irregular structures. In addition to the experimental analysis, thermo-kinetic simulations are carried out with the software package MatCalc. The numerically calculated evolution of the mean radii as well as the time-temperature-precipitation (TTP) diagram for AlN precipitation in the present alloy show good agreement with experiment. [ABSTRACT FROM AUTHOR]

Although a considerable amount of research has examined the impact of experience on negotiation behavior and performance, we still know very little about the usefulness of student samples in negotiation research because most studies have compared the performance of inexperienced students with those who had received some kind of extensive negotiation training or with experienced professional negotiators(s). Against this background, we investigate whether the results obtained from trained student samples are generally similar to those of professional negotiators. Generally, our data confirm our hypotheses that students with some negotiation training and experience perform better than untrained student negotiators and that they are not significantly outperformed by professional negotiators. From this, we conclude that many questions in the field of negotiation research can be effectively tested by using trained students as experimental subjects. [ABSTRACT FROM AUTHOR]

Objectives: To analyse the possible effects of the socioeconomic status (SES) on the prosthetic replacement of missing teeth in working-age people and to explore the role of potential confounders. Methods: Cross-sectional data were collected from 2310 German adults aged 30–59 years. The relationship between each of the three SES indicators (education, income, and occupational status) and dental prostheses were examined by multinomial logistic regression analyses. For that, partially dentate participants with suboptimal and no replacement of missing teeth were compared with partially dentate participants having optimal replacement. Potential confounders (age, sex, dental status, social network and social support) were entered if their inclusion in the model led to ≥10% change in the coefficient of interest. Results: Social network and social support did not meet the criterion for confounding. In the maxilla, having no replacement was positively associated with lower categories for each of the three SES indicators [Odds ratios (OR) between 1.6 and 2.1; 95% confidence intervals (CI) between 1.1 and 3.4]. Low occupational status was the single predictor for suboptimal dental prostheses (OR = 3.2; 95% CI: 1.6–6.2). In the mandible, occupational status showed no association with the prosthetic status, whereas low educational level and low household income were determinants for having no replacement (OR = 1.9 and 1.9, 95% CI: 1.0–3.5 and 1.1–3.0, respectively). Low household income was the single determinant for suboptimal replacement of missing teeth (OR = 2.4, 95% CI = 1.1–5.2). Conclusion: The findings may indicate the relevance of the financing of prosthodontic treatment. The strong association between various forms of upper dentures and occupational prestige can be seen as key contributing concept to how individuals′ characteristics affect the outcome in prosthodontic care. [ABSTRACT FROM AUTHOR]

The carboxy-terminal domain of the transcription factor Escherichia coli NusA, NusACTD, interacts with the protein N of bacteriophage λ, λN, and the carboxyl terminus of the E. coli RNA polymerase α subunit, αCTD. We solved the solution structure of the unbound NusACTD with high-resolution nuclear magnetic resonance (NMR). Additionally, we investigated the binding sites of λN and αCTD on NusACTD using NMR titrations. The solution structure of NusACTD shows two structurally similar subdomains, NusA(353-416) and NusA(431-490), matching approximately two homologous acidic sequence repeats. Further characterization of NusACTD with 15N NMR relaxation data suggests that the interdomain region is only weakly structured and that the subdomains are not interacting. Both subdomains adopt an (HhH)2 fold. These folds are normally involved in DNA-protein and protein-protein interactions. NMR titration experiments show clear differences of the interactions of these two domains with αCTD and λN, in spite of their structural similarity. [ABSTRACT FROM AUTHOR]