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Mechanical engineering curriculums at German universities have mostly theoretical approaches to design theory. Several institutes and chairs have specialized courses regarding this topic, but these are seldomly integrated. The approach IDEE – Integrated Design Engineering Education – brings the specialized fields on design theory together in one course with a highly practical focus at the beginning of the mechanical engineering studies. This is realized by a mixture of theoretical lectures and a group project. For students, this includes their first experience of a complex group project with peers and also the first oral presentation in an engineering context. With a lack of professional and soft skills, there is often friction inside groups. There is also a need for appropriate tools to work collaboratively. Due to the Corona pandemic, lectures and the group project must be held completely online. This paper describes our approach in helping the students improve their professional and personal skills by integrating new courses within the project, monitor their group dynamics, and also use digitization to provide an online-only solution. This paper presents the challenges regarding soft skills and collaborative work as well as the chosen approach on how to integrate digitization, monitoring, and self-organization skills into the lecture to face the challenges.

In scanning transmission electron microscopy using a high-angle annular dark field detector, image intensity strongly depends on specimen thickness and composition. In this paper we show that measurement of image intensities relative to the intensity of the incoming electron beam allows direct comparison with simulated image intensities, and thus quantitative measurement of specimen thickness and composition. Simulations were carried out with the frozen lattice and absorptive potential multislice methods. The radial inhomogeneity of the detector was measured and taken into account. Using a focused ion beam (FIB) prepared specimen we first demonstrate that specimen thicknesses obtained in this way are in very good agreement with a direct measurement of the thickness of the lamella by scanning electron microscopy in the FIB. In the second step we apply this method to evaluate the composition of Al x Ga 1 - x N / GaN layers. We measured ratios of image intensities obtained in regions with unknown and with known Al-concentration x , respectively. We show that estimation of the specimen thickness combined with evaluation of intensity ratios allows quantitative measurement of the composition x . In high-resolution images we find that the image intensity is well described by simulation if the simulated image is convoluted with a Gaussian with a half-width at half-maximum of 0.07 nm.

Transient tachypnea of the newborn (TTN) is the most common cause of neonatal respiratory distress; its estimated incidence is 1 % to 2%. Although a number of risk factors for TTN have been identified, the main risk factors include elective cesarean section (ECS), lower gestational age, male gender, and low birth weight. Previous studies have shown a positive impact of labor on respiratory outcomes among infants with TTN, but the impact of labor on the severity of TTN has not been investigated. This population-based cohort study investigated the effect of labor on the risk and course of TTN in a large, representative sample of term singleton neonates in Germany. Between 2001 and 2005, perinatal databases in the federal states of Hesse and Saarland were used to identify cases of TTN among singletons born at a gestational age ≥37 weeks, and to examine neonatal outcomes in all infants admitted to a neonatal center. Data for the TTN group was compared with national perinatal data for term singletons (control group) born during the study period. The International Classification of Diseases, 10th Revision was used to diagnosis TTN. Of the 239,971 term births included in the final analysis, 13,346 (5.6%) were transferred to a neonatal ward and 1423 (0.59%) cases of TTN were diagnosed. This represented an overall TTN incidence of 5.9 cases per 1000 singleton live births. Risk factors for TTN included ECS, low gestational age, male gender, and low birth weight. There was a significant association between the absence of labor before birth and longer duration of oxygen supplementation (P < 0.02), and an increased risk of TTN and severity of TTN at term. Prolonged labor reduced the need for oxygen supplementation and conversely, a decrease in labor duration increased the need (P < 0.028). These findings show that ECS and the absence of labor at term are strong risk factors for the development of TTN. Absence of labor or reduced labor duration is associated with increased severity of TTN and the need for oxygen supplementation.

Investigation of composition in InGaN quantum wells and quantum dots by TEM is hampered by formation of electron beam induced agglomeration of indium, which occurs if the specimen is exposed to the electron beam for a few minutes. In this contribution we demonstrate that compositional analysis of InGaN nanostructures is possible without this artifact if STEM Z-contrast imaging is applied instead of parallel beam illumination. The suggested method for composition analysis in InGaN is based on a comparison of intensity normalized with respect to the incident electron beam with simulated image intensity. Simulations are performed with the STEMsim program using the frozen lattice multislice approximation for which static atomic displacements were taken into account.