Direct and indirect cumulative effects of temperature, nutrients, and light on phytoplankton growth.

Temperature and resource availability are pivotal factors influencing phytoplankton community structures. Numerous prior studies demonstrated their significant influence on phytoplankton stoichiometry, cell size, and growth rates. The growth rate, serving as a reflection of an organism's success within its environment, is linked to stoichiometry and cell size. Consequently, alterations in abiotic conditions affecting cell size or stoichiometry also exert indirect effects on growth. However, such results have their limitations, as most studies used a limited number of factors and factor levels which gives us limited insights into how phytoplankton respond to environmental conditions, directly and indirectly. Here, we tested for the generality of patterns found in other studies, using a combined multiple-factor gradient design and two single species with different size characteristics. We used a structural equation model (SEM) that allowed us to investigate the direct cumulative effects of temperature and resource availability (i.e., light, N and P) on phytoplankton growth, as well as their indirect effects on growth through changes in cell size and cell stoichiometry. Our results mostly support the results reported in previous research thus some effects can be identified as dominant effects. We identified rising temperature as the dominant driver for cell size reduction and increase in growth, and nutrient availability (i.e., N and P) as dominant factor for changes in cellular stoichiometry. However, indirect effects of temperature and resources (i.e., light and nutrients) on species' growth rates through cell size and cell stoichiometry differed across the two species suggesting different strategies to acclimate to its environment.

[Sustainable residency training in urology in context of current changes in the German healthcare system]. / Nachhaltige Weiterbildung in der Urologie vor dem Hintergrund der aktuellen Veränderungen im deutschen Gesundheitssystem.

Promoting sustainable structures and measures in residency is crucial to meet current and future requirements of the German healthcare system. This process does not only involve the integration of social, ecological, and economic aspects into everyday professional life but also into residency training. Specifically, sustainable structures and measures in residency include initiatives such as structured training curricula, simulation-based training, digital training opportunities, flexible working time models, and gender equality. In addition, consideration of environmental aspects as well as expansion of quality management programs are essential. A holistic approach that considers both the efficiency and the needs of physicians and their patients is the key to sustainable urologic residency programs. This way, urology will remain an attractive specialty for future generations.