The Largest Respectful Function

Respectful functions were introduced by Sangiorgi as a compositional tool to formulate short and clear bisimulation proofs. Usually, the larger the respectful function, the easier the bisimulation proof. In particular the largest respectful function, defined as the pointwise union of all respectful functions, has been shown to be very useful. We here provide an explicit and constructive characterization of it

Semiclassical spin damping: Superradiance revisited

A well known description of superradiance from pointlike collections of many atoms involves the dissipative motion of a large spin. The pertinent ``superradiance master equation'' allows for a formally exact solution which we subject to a semiclassical evaluation. The clue is a saddle-point approximation for an inverse Laplace transform. All previous approximate treatments, disparate as they may appear, are encompassed in our systematic formulation. A byproduct is a hitherto unknown rigorous relation between coherences and probabilities. Our results allow for generalizations to spin dynamics with chaos in the classical limit.Comment: 12 pages standard revtex; to be published in EPJ

Zeitgemäß oder anachronistisch? Zwangseinweisungspraxis in Frankfurt am Main

Background: The evaluation of local mental health care remains difficult. For this reason systematic development of appropriate services is barely possible. Methods: We examined involuntary hospitalization in the city of Frankfurt/Main with regard to diagnoses, socio-demographic data, complementary psychosocial outpatient care, and circumstances of hospitalization. There are four psychiatric clinics, each serving a catchment area of more than 165.000 inhabitants. These clinics are responsible for all psychiatric in-patient treatments regardless of the admission modus. During a one year period, 677 patients were involuntarily hospitalized. Statistical analyses were performed subsequent to pooling the data. Results: During a period of one year, 103 out of 100.000 inhabitants of Frankfurt/Main were admitted involuntarily. The rate of involuntary admissions related to all admissions was 10.98 percent. Any complementary psychosocial care was missing in more than 70 percent of patients admitted involuntarily. Only about 10 percent of patients were examined by a physician before reaching the hospital and in disappointing 1.3 percent the municipal mental health service had been consulted prior to involuntarily admission. Conclusion: Our results show that a systematic improvement of precautionary complementary psychosocial care for risk patients is needed as well as the obligation of psychiatric emergency consultation before involuntary hospitalization.Anliegen: In der gemeindepsychiatrischen Versorgung ist eine systematische Datenerhebung bislang unzureichend etabliert. Daher ist eine planvolle Entwicklung von Versorgungsstrukturen kaum möglich. Zur weiteren Qualitätsverbesserung der gemeindepsychiatrischen Struktur soll eine verlässliche Datenbasis geschaffen werden. Methode: Das durch den Sozialpsychiatrischen Dienst initiierte Projekt PISA untersuchte 677 Zwangseinweisungen in die Versorgungskliniken der Stadt Frankfurt/Main. Ergebnisse: Bei über 70 % der Patienten fehlte eine komplementäre psychosoziale Versorgung, nur 10 % wurden außerhalb der Klinik vor der Einweisung ärztlich untersucht, nur 1,3 % durch den Sozialpsychiatrischen Dienst. Schlussfolgerungen: Eine gezielte Ausweitung ambulanter Hilfesysteme und die Hinzuziehung fachärztlicher Kompetenz vor einer Zwangseinweisung erscheinen dringend erforderlich

Classical versus Quantum Time Evolution of Densities at Limited Phase-Space Resolution

We study the interrelations between the classical (Frobenius-Perron) and the quantum (Husimi) propagator for phase-space (quasi-)probability densities in a Hamiltonian system displaying a mix of regular and chaotic behavior. We focus on common resonances of these operators which we determine by blurring phase-space resolution. We demonstrate that classical and quantum time evolution look alike if observed with a resolution much coarser than a Planck cell and explain how this similarity arises for the propagators as well as their spectra. The indistinguishability of blurred quantum and classical evolution implies that classical resonances can conveniently be determined from quantum mechanics and in turn become effective for decay rates of quantum correlations.Comment: 10 pages, 3 figure

Automatic detection of accommodation steps as an indicator of knowledge maturing

Jointly working on shared digital artifacts – such as wikis – is a well-tried method of developing knowledge collectively within a group or organization. Our assumption is that such knowledge maturing is an accommodation process that can be measured by taking the writing process itself into account. This paper describes the development of a tool that detects accommodation automatically with the help of machine learning algorithms. We applied a software framework for task detection to the automatic identification of accommodation processes within a wiki. To set up the learning algorithms and test its performance, we conducted an empirical study, in which participants had to contribute to a wiki and, at the same time, identify their own tasks. Two domain experts evaluated the participants’ micro-tasks with regard to accommodation. We then applied an ontology-based task detection approach that identified accommodation with a rate of 79.12%. The potential use of our tool for measuring knowledge maturing online is discussed