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Optimized Gaussian basis sets for Goedecker-Teter-Hutter pseudopotentials

We have optimized the exponents of Gaussian s and p basis functions for the elements H, B-F and Al-Cl using the pseudopotentials of (Goedecker, Teter and Hutter 1996 Phys. Rev. B 54 1703) by minimizing the total energy of dimers. We found that this procedure causes the Gaussians to be somewhat more localized than the usual procedure, where the exponents are optimized for atoms. We further found th

Measurement and control of the frequency chirp rate of high-order harmonic pulses

We measure the chirp rate of harmonics 13 to 23 in argon by cross correlation with a 12 femtosecond probe pulse. Under low ionization conditions, we directly measure the negative chirp due to the atomic dipole phase, and show that an additional chirp on the pump pulse is transferred to the qth harmonic as q times the fundamental chirp. Our results are in accord with simulations using the experimen

The physical basis of model-free analysis of NMR relaxation data from proteins and complex fluids

NMR relaxation experiments have provided a wealth of information about molecular motions in macromolecules and ordered fluids. Even though a rigorous theory of spin relaxation is available, the complexity of the investigated systems often makes the interpretation of limited datasets challenging and ambiguous. To allow physically meaningful information to be extracted from the data without commitme

Strong interactions in dye-sensitized interfaces

Phthalocyanines (Pcs) are capable of converting sunlight into electric energy when adsorbed on TiO2 in a dye-sensitized solar cell. Of special interest in this type of cell is the energy level alignment as well as how molecules adsorb on the surface as it determines the output of the cell. We investigated the FePc-TiO2(110) interface using scanning tunneling microscopy, synchrotron-based photoelec

Local Flip Angle Correction for Improved Volume T1-Quantification in Three-Dimensional dGEMRIC Using the Look-Locker Technique

Purpose: To present an evaluation method for three-dimensional Look-Locker (3D-LL) based T1 quantification, calculating correct T1 values independent of local flip angle (FA) variations. The method was evaluated both in phantoms and in vivo in a delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC) study with 33 subjects. Materials and Methods: T1 was measured with 3D-LL, using both local FA corr

Astrophysical lasers in optical Fe II lines in gas condensations near η Carinae

We report here on the discovery of laser action in the range 0.9-2 μm in several spectral lines of Fe II, which are associated with transitions from "pseudo-metastable" states populated by spontaneous transitions from Lyα pumped Fe II levels. The intense Lyα radiation is formed in the HII region of gas condensations close to the star η Car. The laser transitions form together with spontaneous tran

EGF infusion stimulates the proliferation and migration of embryonic progenitor cells transplanted in the adult rat striatum

Immature progenitor cells (generated by in vitro propagation) may provide a useful alternative to primary cells (from dissected embryonic tissue) for transplantation if their migratory and proliferative and differentiation properties can be controlled and directed in vivo. In this study E15 murine EGF-responsive progenitor cells were transplanted to the striatum of adult rats. Simultaneously, thes

Postcollision interaction in noble gas clusters: Observation of differences in surface and bulk line shapes

The surface and bulk components of the x-ray photoelectron spectra of free noble gas clusters are shown to display differences in the influence of postcollision interaction between the photoelectron and the Auger electron on the spectral line shape; the bulk component is observed to be less affected than the surface and atomic parts of the spectra. A model for postcollision interaction in nonmetal

Distribution and isotopic composition of bacterial lipid biomarkers in microbial mats from a sulfidic Icelandic hot spring

Green, nonsulfur-like bacteria (GNSLB) and cyanobacteria form major components of microbial mats in both sulfidic and non-sulfidic hot springs and have been mainly studied in hot springs of Yellowstone National Park (YNP). These organisms synthesize specific lipid biomarkers Such as wax esters and long chain polyunsaturated alkenes (GNSLB) and heptadecane (cyanobacteria). We analyzed the lipid dis

Defining assessment projects and scenarios for policy support: Use of ontology in Integrated Assessment and Modelling

Integrated Assessment and Modelling (IAM) provides an interdisciplinary approach to support ex-ante decision-making by combining quantitative models representing different systems and scales into a framework for integrated assessment. Scenarios in IAM are developed in the interaction between scientists and stakeholders to explore possible pathways of future development. As IAM typically combines m

MWNT reinforced melamine-formaldehyde containing alpha-cellulose

Multi-wall carbon nanotubes (MWNT) were used as reinforcement for melamine-formaldehyde (MF). They were oxidised in HNO3/ H2SO4 mixture and analyzed by means of X-ray Photoelectron Spectroscopy (XPS). Two anionic surfactants: sodium dodecyl sulphate (SDS) and sodium dodecylbenzenesulfonate (NaDDBS) were used to assist the dispersion of nanotubes. The MWNT content was varied from 0 to 1.0 wt%, and

Dye-sensitization of the TiO2 rutile (110) surface by perylene dyes: Quantum-chemical periodic B3LYP computations

The adsorption of perylene derivatives on the rutile TiO2(110) surface was studied by quantum-chemical periodic calculations employing the hybrid HF-DFT functional B3LYP. The perylene molecule, which is a possible constituent of dyes in dye-sensitized solar cells, was functionalized by attachment of phosphonic acid or carboxylic acid groups to permit anchoring to the metal oxide surface. The ancho

Elevated levels and distinct patterns of expression of A-type cyclins and their associated cyclin-dependent kinases in male germ cell tumors

Aberrant expression of several key regulators controlling the G1/S phase of the cell cycle has been implicated in human male germ cell tumorigenesis. Given the critical role of cyclin A2 at both the G1/S and G2/M transitions and the essential role for cyclin A1 in male germ cell development, our present study focused on the involvement of the A-type cyclins in the transformation and progression of

Hyperfine-dependent lifetimes in Be-like ions

Theoretical investigations of hyperfine quenching of the two metastable levels 1s(2)2s2p P-3(0) and P-3(2) have been performed along the Be-like isoelectronic sequence for ions between Z=6-22. It is shown that the lifetime of the latter level is sensitive to hyperfine quenching in the beginning of the isoelectronic sequence, but the sensitivity decreases towards the high-Z end. It is also shown th

Molecularly imprinted polymer formats for capillary electrochromatography

The research aimed towards the adaptation of molecularly imprinted polymers (MIPs) to the capillary format and the use of these highly selective matrices for capillary electrochromatography (CEC) is reviewed in this article. The MIP is prepared by incorporation of a template molecule into a polymerization protocol. After polymerization and extraction of the template from the resulting polymer a hi

Mechanochemical model for myosin V

A rigorous numerical test of a hypothetical mechanism of a molecular motor should model explicitly the diffusive motion of the motor's degrees of freedom as well as the transition rates between the motor's chemical states. We present such a Brownian dynamics, mechanochemcial model of the coarse-grain structure of the dimeric, linear motor myosin V. Compared with run-length data, our model provides