A major challenge in biology is understanding how organisms partition limited resources among physiological processes. For example, offspring production and self-maintenance are important for fitness and survival, yet these critical processes often compete for resources. While physiological trade-offs between reproduction and immune function have been documented, their regulation remains unclear. Most current evidence suggests that physiological changes during specific reproductive states directly suppress various components of the immune system; however, some studies have not found this clear relationship. We performed two experiments in female tree lizards (Urosaurus ornatus) that demonstrate the presence of trade-offs between the reproductive and immune systems under controlled laboratory conditions. These results also support the hypothesis that these trade-offs are a facultative response to resource availability and are not obligatory responses to physiological changes during reproduction. We found that (1) experimentally increasing reproductive investment under limited resources resulted in suppressed immune function and (2) experimentally limiting resources resulted in immunosuppression but only during resource costly reproductive activities. There seems to be a critical balance of resources that is maintained between multiple processes, and changes in the balance between energy intake and output can have major consequences for immune function.

The optical properties and electronic structure of aluminium nitride are determined using valence electron energy-loss spectroscopy in a dedicated scanning transmission electron microscope. Quantitative analysis of the experimental valence electron energy-loss spectra to determine the electronic structure encompasses single scattering deconvolution of the valence electron energy-loss spectra to calculate the energy-loss function, Kramers-Kronig analysis of the energy-loss function to reveal the complex dielectric function, transformation of the dielectric function into the optical interband transition strength via optical property relations and finally critical-point analysis of the interband transition strength. The influence of both experimental and analytical parameters on the final result was studied systematically to define and improve the understanding of the methods. To check the reliability of this technique the interband transition strength determined was compared with results of vacuum ultraviolet spectroscopy. Good agreement was found if sample preparation was taken into account. The preparation of the specimen for the transmission electron microscopy has an effect on the electronic structure. Quantitative analysis of valence electron energy-loss spectroscopy, using the methods presented, is an important and capable method to determine the electronic structure of materials and it has the benefit of high spatial resolution.

The emerging evidence‐based decision‐making phenomenon represents a new opportunity for nursing professionals. This opportunity arises because managed care brings about a new motivation to incorporate existing evidence and research skill into the health care delivery process. In order to participate fully in managed care systems nursing research must be uncompromising in its focus on the characteristics of the client group, the processes of intervention and the outcomes of intervention. It is argued that evidence‐based nursing, as a process, needs to consider three questions. How do we know what practice needs to be changed? How do we enable this change in practice? and how do we ensure that change brings about no further harm? The greatest danger in the process of identification and prioritizing by a group is the bias that can occur because of conscious and unconscious habits associated with power relationships within groups. Nominal Group and Delphi techniques are suggested to alleviate this. Action research is proposed as a method of dealing with, the critical issue of risk management.