Photonic chip based optical frequency comb using soliton induced Cherenkov radiation

By continuous wave pumping of a dispersion engineered, planar silicon nitride microresonator, continuously circulating, sub-30fs short temporal dissipative solitons are generated, that correspond to pulses of 6 optical cycles and constitute a coherent optical frequency comb in the spectral domain. Emission of soliton induced Cherenkov radiation caused by higher order dispersion broadens the spectral bandwidth to 2/3 of an octave, sufficient for self referencing, in excellent agreement with recent theoretical predictions and the broadest coherent microresonator frequency comb generated to date. In a further step, this frequency comb is fully phase stabilized. The ability to preserve coherence over a broad spectral bandwidth using soliton induced Cherenkov radiation marks a critical milestone in the development of planar optical frequency combs, enabling on one hand application in e.g. coherent communications, broadband dual comb spectroscopy and Raman spectral imaging, while on the other hand significantly relaxing dispersion requirements for broadband microresonator frequency combs and providing a path for their generation in the visible and UV. Our results underscore the utility and effectiveness of planar microresonator frequency comb technology, that offers the potential to make frequency metrology accessible beyond specialized laboratories.Comment: Changes: - Added data (new Fig.4) on the first full phase stabilization of a dissipative Kerr soliton (or dissipative cavity soliton) in a microresonator - Extended Fig. 8 in the SI - Introduced nomenclature of dissipative Kerr solitons - Minor other change

Algorithms for highly symmetric linear and integer programs

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch)This paper deals with exploiting symmetry for solving linear and integer programming problems. Basic properties of linear representations of finite groups can be used to reduce symmetric linear programming to solving linear programs of lower dimension. Combining this approach with knowledge of the geometry of feasible integer solutions yields an algorithm for solving highly symmetric integer linear programs which only takes time which is linear in the number of constraints and quadratic in the dimension

Algorithms for highly symmetric linear and integer programs

This paper deals with exploiting symmetry for solving linear and integer programming problems. Basic properties of linear representations of finite groups can be used to reduce symmetric linear programming to solving linear programs of lower dimension. Combining this approach with knowledge of the geometry of feasible integer solutions yields an algorithm for solving highly symmetric integer linear programs which only takes time which is linear in the number of constraints and quadratic in the dimensio

Regionalität: Wettbewerbliche Überlegungen zum Krankenhausmarkt

In den letzten Jahren haben die durch das Bundeskartellamt behandelten Fusionskontrollverfahren im Krankenhaussektor zu einer anhaltenden wettbewerbsökonomischen Debatte geführt. Als eine wichtige Erkenntnis hat sich hierbei ergeben, dass für den überwiegenden Bereich der akutstationären Krankenhausversorgung von einer vergleichsweise engen räumlichen Marktabgrenzung auszugehen ist, der Wettbewerb zwischen Krankenhäusern daher in der Region ausgetragen wird. Das vorliegende Papier untersucht Regionalität und Krankenhauswettbewerb unter verschiedenen Aspekten: Insbesondere beleuchten wir die marktverschließenden Wirkungen der dualistischen Krankenhausfinanzierung, gehen auf die besondere Problematik von Krankenhäusern in der Fusionskontrolle ein und arbeiten das Ob und Wie wesentlicher Konsequenzen von Regionalität in der Versorgung mit Krankenhausleistungen heraus. Zudem greifen wir den Vorschlag der Monopolkommission auf, die Fusionskontrolle im Krankenhausbereich zu verschärfen, um der Regionalität der Krankenhausmärkte gerecht zu werden. -- The increasing number of hospital mergers over the last few years has lead to some debate over the form and degree of competition between hospitals. An important conclusion has been that the geographic definition of the relevant market should be rather narrow when considering inpatient care units. Thus, competition between hospitals takes place in the region. This paper analyses regionalism and hospital competition, highlighting several aspects: We shed light on the market-foreclosing effects of the dual financing system, discuss the special features of hospitals within the German merger control regime and underline the consequences of regionalism for the provision of hospital care. In addition, we follow the proposal made by the German Monopolies Commission to strengthen the merger control regime in order to subject more regional mergers to merger control.

Algorithms for Highly Symmetric Linear and Integer Programs

This paper deals with exploiting symmetry for solving linear and integer programming problems. Basic properties of linear representations of finite groups can be used to reduce symmetric linear programming to solving linear programs of lower dimension. Combining this approach with knowledge of the geometry of feasible integer solutions yields an algorithm for solving highly symmetric integer linear programs which only takes time which is linear in the number of constraints and quadratic in the dimension.Comment: 21 pages, 1 figure; some references and further comments added, title slightly change

Wettbewerbspotenziale im deutschen Apothekenmarkt

Der vorliegende Beitrag analysiert den Ordnungsrahmen für den deutschen Apothekenmarkt und die dortigen Konkurrenzbeziehungen, welche durch signifikante Wettbewerbsdefizite gekennzeichnet sind. Ausgehend von unserer Diagnose und den Befunden werden die Vor- und Nachteile von zwei Therapieoptionen als diskutiert: Das sogenannte Selektivertragsmodell, bei dem Apotheken um das Kollektiv der Versichertengemeinschaft einer jeden Krankenkasse konkurrieren, und das Modell der Apothekentaxe, bei dem die Patienten die Leistung der Apotheke direkt vergüten. Für das Modell der Apothekentaxe werden in drei Szenarien die Wettbewerbswirkungen und das mögliche Einsparpotenzial pro Jahr ermittelt, dass sich auf bis zu 448 Mio. EUR beläuft. -- This paper analyses the institutional framework for pharmacies in Germany and competition in that sector, which is characterized by significant competition deficits. Based on our diagnosis and findings the advantages and disadvantages of two therapies are discussed: The selective contracting model, where pharmacies compete for the collective group of all members of every health insurance company, and the pharmacy fee model, where patients have to directly pay for pharmacy services. For the latter model we analyze, under three different scenarios, the competitive effects and annual saving potentials which can amount up to 448 million euro.Apotheke,Wettbewerb,Gesundheitsausgaben,Effizienz,Nachhaltigkeit,pharmacies,competition,health-care expenditures,efficiency,sustainability

Air Pollution and Lymphocyte Phenotype Proportions in Cord Blood

Effects of air pollution on morbidity and mortality may be mediated by alterations in immune competence. In this study we examined short-term associations of air pollution exposures with lymphocyte immunophenotypes in cord blood among 1,397 deliveries in two districts of the Czech Republic. We measured fine particulate matter < 2.5 μm in diameter (PM(2.5)) and 12 polycyclic aromatic hydrocarbons (PAHs) in 24-hr samples collected by versatile air pollution samplers. Cord blood samples were analyzed using a FACSort flow cytometer to determine phenotypes of CD3(+) T-lymphocytes and their subsets CD4(+) and CD8(+), CD19(+) B-lymphocytes, and natural killer cells. The mothers were interviewed regarding sociodemographic and lifestyle factors, and medical records were abstracted for obstetric, labor and delivery characteristics. During the period 1994 to 1998, the mean daily ambient concentration of PM(2.5) was 24.8 μg/m(3) and that of PAHs was 63.5 ng/m(3). In multiple linear regression models adjusted for temperature, season, and other covariates, average PAH or PM(2.5) levels during the 14 days before birth were associated with decreases in T-lymphocyte phenotype fractions (i.e., CD3(+) CD4(+), and CD8(+)), and a clear increase in the B-lymphocyte (CD19(+)) fraction. For a 100-ng/m(3) increase in PAHs, which represented approximately two standard deviations, the percentage decrease was −3.3% [95% confidence interval (CI), −5.6 to −1.0%] for CD3(+), −3.1% (95% CI, −4.9 to −1.3%) for CD4(+), and −1.0% (95% CI, −1.8 to −0.2%) for CD8(+) cells. The corresponding increase in the CD19(+) cell proportion was 1.7% (95% CI, 0.4 to 3.0%). Associations were similar but slightly weaker for PM(2.5). Ambient air pollution may influence the relative distribution of lymphocyte immunophenotypes of the fetus

Discrete cytosolic macromolecular BRAF complexes exhibit distinct activities and composition

As a central element within the RAS/ERK pathway, the serine/threonine kinase BRAF plays a key role in development and homeostasis and represents the most frequently mutated kinase in tumors. Consequently, it has emerged as an important therapeutic target in various malignancies. Nevertheless, the BRAF activation cycle still raises many mechanistic questions as illustrated by the paradoxical action and side effects of RAF inhibitors. By applying SEC‐PCP‐SILAC, we analyzed protein–protein interactions of hyperactive BRAFV600E and wild‐type BRAF (BRAFWT). We identified two macromolecular, cytosolic BRAF complexes of distinct molecular composition and phosphorylation status. Hyperactive BRAFV600E resides in large complexes of higher molecular mass and activity, while BRAFWT is confined to smaller, slightly less active complexes. However, expression of oncogenic K‐RasG12V, either by itself or in combination with RAF dimer promoting inhibitors, induces the incorporation of BRAFWT into large, active complexes, whereas pharmacological inhibition of BRAFV600E has the opposite effect. Thus, the quaternary structure of BRAF complexes is shaped by its activation status, the conformation of its kinase domain, and clinically relevant inhibitors