Photochemical Reductive trans-Elimination from trans-Diacidotetracyanoplatinate(IV) Complexes

Abstract Upon CT excitation the complex ions trans-[Pt(CN)4N3X]2- and trans-[Pt(CN)4X2]2- (X = Cl and Br) undergo a reductive trans-elimination with formation of [Pt(CN)4]2- and two ligand radicals in the photoprimary step. The formation of a Pt(III) intermediate is not observed. Due to the stability of [Pt(CN)4]2-, recombination reactions regenerating the starting complex are efficient if the ligand radicals are not scavenged. For the azide complexes the high quantum yields for the production of [Pt(CN)4]2- are explained by the instability of azide radicals. For trans-[Pt(CN)4X2]2-, the recombination is efficient in aqueous solution, while in ethanol the halogen atoms are scavenged by hydrogen abstraction. The sequence of steps following CT excitation can be explained by a potential energy diagram.</jats:p

Imaging through turbulence with a quadrature-phase optical interferometer

We present an improved technique for imaging through turbulence at visible wavelengths using a rotation shearing pupil-plane interferometer, intended for astronomical and terrestrial imaging applications. While previous astronomical rotation shearing interferometers have made only visibility modulus measurements, this interferometer makes four simultaneous measurements on each interferometric baseline, with phase differences of π/2 between each measurement, allowing complex visibility measurements (modulus and phase) across the entire input pupil in a single exposure. This technique offers excellent wavefront resolution, allowing operation at visible wavelengths on large apertures, is potentially immune to amplitude fluctuations (scintillation), and may offer superior calibration capabilities to other imaging techniques. The interferometer has been tested in the laboratory under weakly aberrating conditions and at Palomar Observatory under ordinary astronomical observing conditions. This research is based partly on observations obtained at the Hale Telescope

Slx5/Slx8-dependent ubiquitin hotspots on chromatin contribute to stress tolerance

Chromatin is a highly regulated environment, and protein association with chromatin is often controlled by post-translational modifications and the corresponding enzymatic machinery. Specifically, SUMO-targeted ubiquitin ligases (STUbLs) have emerged as key players in nuclear quality control, genome maintenance, and transcription. However, how STUbLs select specific substrates among myriads of SUMOylated proteins on chromatin remains unclear. Here, we reveal a remarkable co-localization of the budding yeast STUbL Slx5/Slx8 and ubiquitin at seven genomic loci that we term "ubiquitin hotspots". Ubiquitylation at these sites depends on Slx5/Slx8 and protein turnover on the Cdc48 segregase. We identify the transcription factor-like Ymr111c/Euc1 to associate with these sites and to be a critical determinant of ubiquitylation. Euc1 specifically targets Slx5/Slx8 to ubiquitin hotspots via bipartite binding of Slx5 that involves the Slx5 SUMO-interacting motifs and an additional, novel substrate recognition domain. Interestingly, the Euc1-ubiquitin hotspot pathway acts redundantly with chromatin modifiers of the H2A.Z and Rpd3L pathways in specific stress responses. Thus, our data suggest that STUbL-dependent ubiquitin hotspots shape chromatin during stress adaptation

Ultrafast photodoping and effective Fermi-Dirac distribution of the Dirac particles in Bi2Se3

We exploit time- and angle- resolved photoemission spectroscopy to determine the evolution of the out-of-equilibrium electronic structure of the topological insulator Bi2Se. The response of the Fermi-Dirac distribution to ultrashort IR laser pulses has been studied by modelling the dynamics of the hot electrons after optical excitation. We disentangle a large increase of the effective temperature T* from a shift of the chemical potential mu*, which is consequence of the ultrafast photodoping of the conduction band. The relaxation dynamics of T* and mu* are k-independent and these two quantities uniquely define the evolution of the excited charge population. We observe that the energy dependence of the non-equilibrium charge population is solely determined by the analytical form of the effective Fermi-Dirac distribution.Comment: 5 Pages, 3 Figure

A scalable optical detection scheme for matter wave interferometry

Imaging of surface adsorbed molecules is investigated as a novel detection method for matter wave interferometry with fluorescent particles. Mechanically magnified fluorescence imaging turns out to be an excellent tool for recording quantum interference patterns. It has a good sensitivity and yields patterns of high visibility. The spatial resolution of this technique is only determined by the Talbot gratings and can exceed the optical resolution limit by an order of magnitude. A unique advantage of this approach is its scalability: for certain classes of nano-sized objects, the detection sensitivity will even increase significantly with increasing size of the particle.Comment: 10 pages, 4 figure

Steuerung des GKV-Arzneimittelmarktes – Auswirkungen von Selbstbeteiligungen und Härtefallregelungen

This analysis shows that hardship and not hardship cases respectively reject clear differences both at the demand and at the expenditures for pharmaceuticals financed by the statutory health insurance. Hardship cases without exemption regulations would be burden therefore by enormous co-payments. Moreover, it also turns out that straight hardship cases are less healthy on average than not hardship cases. Co-payments without accompanying hardship case regulations would therefore hardly make a supply possible adapted to the needs of hardship cases. On the other hand the effectivity of drug co-payment regulations is reduced by hardship case regulations considerably.co-payments, pharmaceutical market, statutory health insurance, public finance

Kopfpauschalen zur Finanzierung der Krankenversicherungsleistungen in Deutschland

In letzter Zeit wurde von einigen Wissenschaftlern der Vorschlag gemacht, die Finanzierung der gesetzlichen Krankenversicherung auf einkommensunabhängige Kopfpauschalen umzustellen. Die Autoren stellen in dieser Arbeit deshalb einleitend die unterschiedlichen Vorschläge verschiedener Gutachter zur Kopfprämienfinanzierung vor. Anschließend werden Modellrechnungen zur Höhe und zu den Be- und Entlastungswirkungen einer Kopfpauschale präsentiert. Darüber hinaus werden Schätzungen zum notwendigen Steuertransferbedarf sowie zur Gegenfinanzierung dargestellt. Zur Einschätzung der Auswirkungen von Kopfpauschalen in der praktischen Umsetzung werden die Erfahrungen mit Kopfpauschalen in der Schweiz, die als einziges Land in Europa diese Finanzierungsvariante anwendet, analysiert.Recently several experts have proposed to replace the existing social health insurance revenue system by income-independent per capita contributions. Therefore the authors of this paper present different estimates for alternative forms of per capita contributions. The next step of the analysis involves calculating the reduction or increase in contribution burden following a change to a per capita contribution system. Furthermore the volume of the tax transfer required to off-set the lower income groups? massive worsening of their income position and the higher income groups? increased tax burden is estimated. Some of the problems involved in the practical application of introducing such a revenue system in Switzerland ? the only European country applying this form of financing alternative ? are addressed. The concluding section summarizes the effects of such a revenue system