Billing and insurance-related functions have been reported to consume 14 percent of medical group revenue, but little is known about the costs associated with performing specific activities. We conducted semistructured interviews, observed work flows, analyzed department budgets, and surveyed clinicians to evaluate these activities at a large multispecialty medical group. We identified 0.67 nonclinical full-time-equivalent (FTE) staff working on billing and insurance functions per FTE physician. In addition, clinicians spent more than thirty-five minutes per day performing these tasks. The cost to medical groups, including clinicians' time, was at least $85,276 per FTE physician (10 percent of revenue).

The temperature dependence of the geometric structure of amorphous and crystallized Ni33Zr67 was investigated by means of in situ synchrotron X-ray diffraction. The crystal structure parameters of the tetragonal NiZr2 phase were determined by the Rietveld refinement of the X-ray diffraction patterns. The lattice parameters a0, c0, and therefore the interatomic distances increase linearly with temperature. The behavior of the short-range order was analyzed by the corresponding atomic pair correlation functions G(r). The position of the first maximum of G(r) at r1 decreases with temperature. The analysis of real space data of the crystallized state of Ni33Zr67 shows that the measured G(r) function consists of several superimposed, non-resolved inter-atomic distances. The individual distances increase with temperature in agreement with the Rietveld analysis. The position of the first maximum r1 is additionally influenced by the thermal broadening of the distance distributions leading to the “unphysical” reduction of r1 with temperature.

The thermal behavior of Pd40Cu30Ni10P20 and Zr60Ti2Cu20Ni8Al10 bulk metallic glasses has been investigated in situ through the glass transition by means of differential scanning calorimetry, high-temperature X-ray synchrotron diffraction, and electrical resistivity. The temperature dependence of the X-ray structure factor can be well described by the Debye theory within the glassy state with a Debye temperature of θ=296K for Pd40Cu30Ni10P20, and θ=418K for Zr60Ti2Cu20Ni8Al10, respectively. At the glass transition temperature the temperature dependence of the structure changes, pointing to a continuous development of structural changes in the liquid state with temperature. The electrical resistivity behaves similar to the structure factor in accordance with Ziman theory.

GeO2 and a sodium aluminosilicate were studied by in-situ high-temperature X-ray diffraction measurements in a wide temperature range from ambient temperature up to temperatures above the liquidus temperature. In order to get information on how intensively the structure changes in the different temperature regions, the family of scattering curves was analyzed by a method based on simple statistical concepts. The overall structural activity of the melt and a specified structural activity, describing only qualitative changes, were determined. The latter function has a strong maximum slightly above Tg, indicating that glass forming begins with a rearrangement of structural units.

The thermal behavior of the structure of Pd40Cu30Ni10P20 bulk metallic glass has been investigated in situ through the glass transition by means of high-temperature x-ray synchrotron diffraction. The dependence of the x-ray structure factor S(q) of the Pd40Cu30Ni10P20 glass on temperature follows the Debye theory up to the glass transition with a Debye temperature θ=296 K. Above the glass transition temperature Tg, the temperature dependence of S(q) is altered, pointing to a continuous development of structural changes in the liquid with temperature. The atomic pair correlation functions g(r) indicate changes in short-range-order parameters of the first and the second neighborhood with temperature. The temperature dependence of structural parameters is different in glass and in supercooled liquid, with a continuous behavior through the glass transition. The nearest-neighbor distance decreases with temperature, changing the slope at Tg. The interatomic distances of higher coordination shells expand analogously to the macroscopic linear thermal expansion.

The structural behavior of the Zr52Ti5Cu18Ni15Al10 bulk glass-forming alloy has been investigated in situ by means of high-temperature x-ray synchrotron diffraction. The dependence of the structure factor of the glass can be well described with a Debye–Waller factor and a Debye temperature θ=412 K. At the glass transition, the structure factor significantly decreases due to additional thermal excitations. The extrapolation of the structure factor of the supercooled liquid to temperatures above the liquidus curve is in agreement with experimentally determined values of the melt. The short-range order of the glass, of the supercooled liquid state, and of the equilibrium melt at T=1193 K, is found to be quite similar. The formation of complex chemically ordered clusters in the melt is proposed to be essential for the high-glass-forming ability of this alloy.

The glass transition and the phase formation during crystallization of the Zr52Ti5Cu18Ni15Al10 bulk metallic glass were followed in situ by high-temperature X-ray diffraction using synchrotron radiation at the high energy beam-line BW5 ( λ = 0.01040 nm) at the storage ring DORIS (HASYLAB, Hamburg). The experimental set-up enables to record intensities in transmission up to scattering vectors q of 200 nm -1 with a measuring time of 20 s per diagram. The crystallization starts with the formation of an extremely fine nanostructure followed by the transformation into tetragonal NiZr2-type crystals plus an unknown phase. Both phases are metastable and transform at about 1123 K into the stable equilibrium phases. The temperature dependence of the structure factor S(q) of the glass can be well described within the framework of the Debye theory. At the glass transition the first derivative dS(q)/dT changes. A Debye temperature Θ = 412 K was estimated for the glassy, and Θ = 162 K for the liquid state of the Zr52Ti5Cu18Ni15Al10 alloy. The short-range order of the glass, of the supercooled liquid state, and of the equilibrium melt at T = 1193 K is found to be quite similar.

Vitreous and molten boron oxide were studied by in situ high-temperature X-ray diffraction. New insights into the structure were gained by adapting the distance correlation function of a carefully chosen model to the experimental correlation function. In case of vitreous B2O3 a network which is made of the same concentration of boroxol groups as of BO3 groups proves to be consistent with the diffraction experiment. A quasi-planar network with closed rings of BO3 groups appears to be an inappropriate model for the structure of molten B2O3. On the other hand, a network which contains `broken-up' boroxol rings is in agreement with diffraction data.

The question as to whether the fraction of 4-fold coordinated boron atoms decreases at higher temperatures has been studied by the x-ray radial distribution method. In order to increase the conclusiveness the coordination of the oxygen atoms was taken into account by using a calculation of most probable values. Nearly identical results, obtained for three different binary borate glasses with 29mol% network modifier oxide, constitute evidence for the decay of BO4 tetrahedra at higher temperatures.

Using synchrotron radiation, WAXS studies on binary alkali silicates, both in the vitreous and molten state, have been performed. Radial difference correlation functions, Dif(r), are obtained by Fourier transform of the weighted interference functions, Qi(Q). The difference correlation functions reflect the decay of the SiO-network in its dependence on network modifier content and temperature. In the case of sodium silicates, the separations as well as the areas under the peaks reveal distinct changes of the NaOn-polyhedrons in the transformation range.

Diffraction experiments, especially in the form of in situ studies, represent one of the main ways for a better understanding of the structure of glass-forming melts. After demonstrating some shortcomings of previous experiments, newer results are reviewed. Besides it is attempted to classify the different oxide melts.

Abstract X-ray diffraction experiments of molten oxide glasses, which give new insights into the structure of melts, were carried out. Using modern means (synchrotron radiation, image plates, container-less high-temperature technique) it could be shown that the short range order of melt and solid glass is often qualitatively different. If vitreous B2O3 or binary borate glasses with low content of network modifier are heated up above Tg , the network topology begins to alter. With rising temperature more and more of the boroxol groups are replaced by independent B0 3 groups. While melting a metaphosphate glass, how-ever, structural changes of another kind take place. In solid glass the environment of the network modifier ions is similar to the one found in crystalline modifications, and their distances to the surrounding PO4 tetrahedra have narrow distributions. In the melt, however, these distances scarcely become evident, probably owing to the increased thermal motion of the modifier ions.

X-ray diffraction measurements of molten binary metaphosphate glasses are described. The changes in the short-range order in the temperature range greater than the glass transition temperature, Tg, are discussed and the differences between the glass and liquid structures are emphasized. The phenomenon of a thermally inducible peak at the smallest Q nm−1 which exists for sodium metaphosphate, but is not detected for diffraction from magnesium or calcium metaphosphate, is regarded as a first sharp diffraction peak (FSDP) and interpreted in terms of the cluster–void picture. The amplitude of the FSDP increases with temperature due to the increase of scattering contrast by the thermal expansion of the NaOn polyhedra. We assert that the FSDP is a sufficient, but not necessary signature of medium-range order.

A high-temperature device is described which allows wide-angle x-ray scattering experiments (WAXS) of molten glasses in transmission arrangement without parasitic scattering and problems due to chemical reactions. The advantage of high heating and cooling rates for glass melt studies is emphasized and problems of temperature measurement and homogeneity are discussed.

The most striking change in the x-ray diffraction pattern of glass which takes place during melting is the generation of a strong first sharp diffraction peak (FSDP). Starting from a model of glass and using reverse Monte Carlo simulations, the structure of molten is approximated by replacing the ions with ions and displacing them in a random manner within the extended cages originally occupied by the larger ions. In this way the increased vibrations and the additional diffusive motion of the ions are taken into account. This motion requires considerably more room in the melt than is occupied by the cations in the glass. The model reproduces the structure factor of the melt, including the FSDP, and explains the disappearance of the peak at 0.35 nm in the total pair distribution function.

High-temperature diffraction studies on molten oxide glasses show that it is necessary to differentiate in describing the structure of melts. There are glasses in which the short range order (SRO) changes markedly in the temperature range above T-g.