Ebullioskopie

Ohne Zusammenfassung     

Zur Untersuchung von Fleischextracten und Fleischpeptonen

Ohne Zusammenfassung     

High throughput screening for orphan and liganded GPCRs

GPCRs had significant representation in the drug discovery portfolios of most major commercial drug discovery organizations for many years. This is due in part to the diverse biological roles mediated by GPCRs as a class, as well as the empirical discovery that they have proven relatively tractable to the development of small molecule therapeutics. Publication of the human genome sequence in 2001 confirmed GPCRs as the largest single gene superfamily with more than 700 members, furthering the already strong appeal of addressing this target class using efficient and highly parallelized platform approaches. The GPCR research platform implemented at Amgen is used as a case study to review the evolution and implementation of available assays and technologies applicable to GPCR drug discovery. The strengths, weaknesses, and applications of assay technologies applicable to G alpha s, G alpha i and G alpha q-coupled receptors are described and their relative merits evaluated. Particular consideration is made of the role and practice of "de-orphaning" and signaling pathway characterization as a pre-requisite to establishing effective screens. In silico and in vitro methodology developed for rapid, parallel high throughput hit characterization and prioritization is also discussed extensively.     

The electrical properties of zinc in silicon

Electrically active deep levels related to zinc in silicon are investigated in n- and p-type silicon using Deep-Level Transient Fourier Spectroscopy (DLTFS) measurements. While in n-type silicon a level at E _C–0.49 eV is observed, the main zinc-related levels in p-type silicon are determined to be E _V+0.27 eV and E _V+0.60 eV. The latter are associated with zinc situated on regular silicon lattice sites. The emission rate of these centers exhibits a field dependence which cannot be quantitatively explained with the Poole-Frenkel model. On the other hand, a shallow level at E _V+0.09 eV is observed only in boron-doped silicon which may be related to a zinc-boron complex. Other zinc-related levels are found at E _V+0.23 eV and E _V+0.33 eV, their concentration depending on that of zinc on substitutional sites. In addition, the evaluation of depth profiles and the analysis of the field dependence of the emission rate based on the DLTFS method is presented.     

Spectra of semi-regular polytopes

We compute the spectra of the adjacency matrices of the semi-regular polytopes. A few different techniques are employed: the most sophisticated, which relates the 1-skeleton of the polytope to a Cayley graph, is based on methods akin to those of Lovász and Babai ([L], [B]). It turns out that the algebraic degree of the eigenvalues is at most 5, achieved at two 3-dimensional solids.Dedicated to the memory of R. MañéResearch supported by MCT and CNPq, Brazil.     

Crystallographic report: Bis(triphenylphosphoranylidene)ammonium phenyltetrachlorotellurate

Unlike most previously described organotetrachlorotellurate complexes, neither secondary Te·Cl interactions nor significant cation–anion interaction are observed in the molecular structure of [Ph₃PNPPh₃][PhTeCl₄]. Copyright © 2005 John Wiley & Sons, Ltd.     

Vakuumgef?sse aus Porzellan

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Thin prism refraction. A new direct method of polariton spectroscopy

Refraction of light by thin prisms has been used for the first time to obtain dispersion curves of excitonic polaritons. This most direct method demonstrated here for the A- and B-exciton in thin prismatic CdS crystals is shown to be extremely precise in spite of its simplicity. Improved values of polariton parameters are reported. In the mixed mode orientation we observed birefringence due to spatial dispersion. This opens a way to study the problem of additional boundary conditions.