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The term Medical Humanities has still not been established in the wider medical, educational and academic communities. This qualitative study, conducted across three acute care trusts, is an exploration of whether clinicians were familiar with the term Medical Humanities, and if so, what the term meant to them and whether they considered the associated concepts relevant to medical practice and education. Reactions to the term Medical Humanities were varied: many clinicians had not heard of the term before, some were unsure what it meant, others displayed mistrust or contempt for it. Explicit definitions that were elicited were categorised (inductively) according to three main approaches to the understanding of Medical Humanities: Humanistic-holistic, Humanities-medicine seperate and Intellectual exercise. Findings indicate that the lack of clarity about the term Medical Humanities among experienced healthcare professionals, contrasts with their sophisticated implicit knowledge of key issues frequently associated with Medical Humanities. Thus, while some clinicians could not define Medical Humanities and some definitions separated humanities from medicine, all clinicians implicitly acknowledged the importance of Medical Humanities issues within their clinical and teaching practices during conversations prior to any mention of the term. It appears that clinicians as role models for medical students can inadvertently convey an ambivalent position towards the Medical Humanities that encompass the very values and attitudes they are trying to inculcate, sending out mixed messages to the novices.

This paper describes a combined theoretical and experimental approach to understanding the capillary spark discharge with specific application to use as a soft x-ray or extreme ultraviolet laser source. Atomic physics calculations have identified several potential laser lines in a collisionally pumped neon-like or nickel-like plasma, and magnetohydrodynamic (MHD) modeling has shown that a capillary discharge device should be capable of producing the correct plasma conditions to achieve a population inversion in some of these lines. An experiment is constructed to evaluate the accuracy of the MHD model and investigate the potential of observing inversion in a neon-like argon or a nickel-like krypton plasma.

A Ne-like laser scheme is considered for a pure silver plasma. Level populations and gain coefficients are calculated with an atomic-kinetics model. It is shown that large gain values (GL100) are achievable in a hot dense quasi-steady-state silver plasma at λ=10.038 nm (2-1 transition) and λ=12.298 nm (0-1 transition). Lasing is also possible at λ=2.75 nm (2s-2p transition). The plasma conditions needed are: electron temperature 3–5keV and density 5 × 1022ne1023;cm-3;. These plasma conditions can be created with a high-contrast, high-intensity short-pulse visible light laser driver.

Multilayers are used in x-ray optics as mirrors.1 They usually consist of a stack of bi-layers of two different materials. For x-ray optics, the thickness of the bi-layer, or the d-spacing of the multilayer, ranges from 2 nm to 20 nm. Since x-ray multilayers are usually made by evaporation or sputtering technique, most of materials in multilayers are amorphous or polycrystalline.

The concept of topological or structural stability is introduced and its importance in the magnetic confinement of plasmas is discussed. Topological stability requires the presence of a pair of limit cycles in the magnetic field configuration. This paper deals with the design of an experimental device possessing limit cycles. The design includes a high beta (s ? 1), high density (~1016), hot (~100 eV) hygrogen plasma which is to be compressed by a factor of about 5 in a toroidal device of 25 cm average major radius with a capacitor bank rise time of less than 2 ?sec. Two shaped toroidal coils with opposing currents and the poloidal compression coils have been designed to give a pressure balance equilibrium and establish the limit cycles. This device could be used to determine the physical significance of topological stability in plasma confinement.

Darwin derived a system of difference equations which relate the incident and reflected amplitudes of X-rays in a crystal in Bragg diffraction. These equations are recast in matrix form. Using a well known result from optical multilayer theory, an exact analytic solution of these difference equations is obtained for a crystal of an arbitrary number of atomic planes. In the limiting case of a semi-infinite crystal, and with the appropriate approximations, Darwin's expression for the reflectivity of a crystal in Bragg diffraction is obtained.

Direct measurements of the force of gravity on charged elementary particles have never been made because of the difficulty of isolating the particles from electric and magnetic fields. Furthermore, no direct measurements have been made of the gravitational force on antimatter. Use of superconducting persistent magnets, cryogenic pumping, and a number of other techniques has enabled us to reduce all vertical forces on a free electron to values comparable to that of gravity, even though the electric force from one electron 5 m away is equal to the gravitational force from the whole earth. An experiment is under way to measure the force of gravity on a free electron and eventually on a free positron. Electrons have already been observed to take 80 msec to travel 15 cm, which indicates that their average kinetic energy is 10-11 eV.