Changes in Hospital Efficiency after Privatization

We investigated the effects of privatization on hospital efficiency in Germany. To do so, we obtained bootstrapped DEA efficiency scores in the first stage of our analysis and subsequently employed a difference-in-difference matching approach within a panel regression framework. Our findings show that conversions from public to private for-profit status were associated with an increase in efficiency of between 3.2 and 5.4%. We defined four alternative post- privatization periods and found that the increase in efficiency after a conversion to private for- profit status appeared to be permanent. We also observed an increase in efficiency one year after hospitals were converted to private non-profit status, but our estimations suggest that this effect was transitory. Our findings also show that the efficiency gains after a conversion to private for-profit status were achieved through substantial decreases in staffing ratios in all analyzed staff categories with the exception of physicians. It was also striking that the efficiency gains of hospitals converted to for-profit status were significantly lower in the DRG era than in the pre-DRG era. Altogether, our results suggest that converting hospitals to private for-profit status may be an effective way to ensure the scarce resources in the hospital sector are used more efficiently.Privatization, Performance measurement, Data envelopment analysis, Propensity score matching, Germany

The use of cost accounting methodologies to determine prices in German health care

In many sectors of the health care system, prices at which providers are reimbursed by payers are not determined by the market mechanism, but rather by a defined administrative process. Depending on the sector, prices are set politically and are negotiated between different actors or are calculated according to a defined procedure, considering cost data from a sample of providers. The selected approach for price setting determines decisively, to which extent prices for certain services reflect the actual costs incurred for these services. A lack of reflection of actual costs can lead to unintended incentives for providers and therefore have implications on the allocative efficiency. Our analysis shows that in Germanys inpatient and outpatient sector, cost data is increasingly considered for price setting while in other sectors such as long-term care and rehabilitation, the use of cost data is still very limited. However, DRG-cost-weights in the inpatient sector insufficiently reflect actual costs incurred. Thus, decision makers in the German health care system rely more on cost data for price setting and improving the accuracy of cost calculations in order to increase allocative efficiency. -- Die Preisbildung für die Erstattung von Leistungserbringern erfolgt in vielen Sektoren des Gesundheitswesens nicht durch den Marktmechanismus, sondern durch einen administrativ definierten Prozess. Je nach Sektor werden politische Preise vorgegeben, unter den Akteuren verhandelt oder nach einem festgelegten Verfahren, unter Berücksichtigung von Kostendaten aus einer Stichprobe von Leistungserbringern, berechnet. Das gewählte Verfahren der Preisbildung determiniert in entscheidendem Maße, inwieweit die Preise für die erbrachten Leistungen die realen Kosten der Leistungserbringer für diese abbilden. Eine mangelnde Reflektion der Kosten in den Preisen kann zu Fehlanreizen für die Leistungserbringer und mithin zu einer Fehlallokation von Ressourcen führen. Im Rahmen dieser Untersuchung zeigt sich, dass in Deutschland im stationären und ambulanten Bereich zunehmend detaillierte Kostendaten für die Preisberechnung herangezogen werden, während dies in anderen Sektoren wie Pflege und Rehabilitation bislang nur sehr bedingt erfolgt. Es zeigt sich jedoch, dass auch im stationären Sektor die DRG-Relativgewichte bislang nur unzureichend die Kosten für die entsprechenden Leistungen abbilden. Insgesamt muss in Deutschland für die Preisbildung im Gesundheitswesen mehr auf Kosteninformationen für die Preisberechnung zurückgegriffen und die Verursachungsgerechtigkeit der Kostenkalkulationen verbessert werden, um die Allokationseffizienz zu erhöhen.

Time-Reversal Symmetry and Universal Conductance Fluctuations in a Driven Two-Level System

In the presence of time-reversal symmetry, quantum interference gives strong corrections to the electric conductivity of disordered systems. The self-interference of an electron wavefunction traveling time-reversed paths leads to effects such as weak localization and universal conductance fluctuations. Here, we investigate the effects of broken time-reversal symmetry in a driven artificial two-level system. Using a superconducting flux qubit, we implement scattering events as multiple Landau-Zener transitions by driving the qubit periodically back and forth through an avoided crossing. Interference between different qubit trajectories give rise to a speckle pattern in the qubit transition rate, similar to the interference patterns created when coherent light is scattered off a disordered potential. Since the scattering events are imposed by the driving protocol, we can control the time-reversal symmetry of the system by making the drive waveform symmetric or asymmetric in time. We find that the fluctuations of the transition rate exhibit a sharp peak when the drive is time-symmetric, similar to universal conductance fluctuations in electronic transport through mesoscopic systems

Three-body effects in the Hoyle-state decay

We use a sequential $R$-matrix model to describe the breakup of the Hoyle state into three $\alpha$ particles via the ground state of $^8\mathrm{Be}$. It is shown that even in a sequential picture, features resembling a direct breakup branch appear in the phase-space distribution of the $\alpha$ particles. We construct a toy model to describe the Coulomb interaction in the three-body final state and its effects on the decay spectrum are investigated. The framework is also used to predict the phase-space distribution of the $\alpha$ particles emitted in a direct breakup of the Hoyle state and the possibility of interference between a direct and sequential branch is discussed. Our numerical results are compared to the current upper limit on the direct decay branch determined in recent experiments

Top-down fabrication of ordered arrays of GaN nanowires by selective area sublimation

We demonstrate the top-down fabrication of ordered arrays of GaN nanowires by selective area sublimation of pre-patterned GaN(0001) layers grown by hydride vapor phase epitaxy on Al$_{2}$O$_{3}$. Arrays with nanowire diameters and spacings ranging from 50 to 90 nm and 0.1 to 0.7 $\mu$m, respectively, are simultaneously produced under identical conditions. The sublimation process, carried out under high vacuum conditions, is analyzed \emph{in situ} by reflection high-energy electron diffraction and line-of-sight quadrupole mass spectromety. During the sublimation process, the GaN(0001) surface vanishes, giving way to the formation of semi-polar $\lbrace1\bar{1}03\rbrace$ facets which decompose congruently following an Arrhenius temperature dependence with an activation energy of ($3.54 \pm 0.07$) eV and an exponential prefactor of $1.58\times10^{31}$ atoms cm$^{-2}$ s$^{-1}$. The analysis of the samples by low-temperature cathodoluminescence spectroscopy reveals that, in contrast to dry etching, the sublimation process does not introduce nonradiative recombination centers at the nanowire sidewalls. This technique is suitable for the top-down fabrication of a variety of ordered nanostructures, and could possibly be extended to other material systems with similar crystallographic properties such as ZnO.Comment: This is the accepted manuscript version of an article that appeared in Nanoscale Advances. The CC BY-NC 3.0 license applies, see http://creativecommons.org/licenses/by-nc/3.0

Noise correlations in a flux qubit with tunable tunnel coupling

We have measured flux-noise correlations in a tunable superconducting flux qubit. The device consists of two loops that independently control the qubit's energy splitting and tunnel coupling. Low frequency flux noise in the loops causes fluctuations of the qubit frequency and leads to dephasing. Since the noises in the two loops couple to different terms of the qubit Hamiltonian, a measurement of the dephasing rate at different bias points provides a way to extract both the amplitude and the sign of the noise correlations. We find that the flux fluctuations in the two loops are anti-correlated, consistent with a model where the flux noise is generated by randomly oriented unpaired spins on the metal surface.Comment: 7 pages, including supplementary materia