A Simple Low-Vacuum Environmental Cell
The environmental cell device discussed in this paper provides a modest low-vacuum scanning electron microscopy (SEM) capability to a standard SEM without requiring additional pumping. This environmental cell confines a volume of low vacuum in contact with the sample surface using a container that has an aperture for admitting the primary electron beam. The aperture is large enough to permit a limited field of view of the sample, and small enough to limit the outflow of gas into the SEM chamber to that which can be accommodated by the standard SEM pumping system. This environmental cell also functions as a gaseous detector device.
Modifying an FESEM for Low-Vacuum Work
Environmental SEM has greatly extended the utility of SEM as a result of an ESEM's ability to image volatile and insulating samples. However, many institutions have older high-vacuum SEMs that they cannot afford to replace with an ESEM. For this reason, a simple and inexpensive pressure cell has been developed for performing low-vacuum SEM in a standard microscope. Rather than backfilling the entire analysis chamber with gas, a small volume of higher pressure is confined at the sample surface with the use of a pressure cell that has a small aperture for admitting the primary beam and a gas inlet. Figure 1 is a photograph of such a simple pressure cell. The aperture for admitting the primary beam needs to be small enough to limit the escaping gas to an amount below what the standard SEM can pump and still maintain high vacuum. On the other hand, the aperture should be as large as possible to provide a useful field of view.
Ethics and the Treatment of the Mentally Ill, Homeless Person: a Perspective on Psychiatry Resident Training
ObjectiveThe authors outline the unique ethical challenges that psychiatry residents face in working with individuals who are homeless and mentally ill. The authors also propose steps to develop effective teaching methods with residents working with these patients.MethodsThe authors reviewed literature relevant to the training of psychiatry residents in ethics and treating individuals who are homeless and mentally ill.ResultsThe authors summarize current literature and, with the use of case examples, provide guidelines for effective teaching.ConclusionsTeaching psychiatry residents who are working in the community with individuals who are mentally ill and homeless needs to address a number of unique ethical conflicts that arise in this area. The authors outline approaches to this teaching.