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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
In the name of the father... and the mother.
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
Extracellular regulation of FGF signaling in the early Xenopus embryo
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
Desmopressin treatment in nocturia; an analysis of risk factors for hyponatremia.
Aims: To explore the incidence, severity, time course, and risk factors of clinically significant hyponatremia in desmopressin treatment for nocturia. Methods: Data from three multi-center phase 111 trials were pooled. Hyponatremia was categorised as borderline (134-130 mmol/L) or significant (= 65 years of age) with a baseline serum sodium concentration below normal range were at high risk (75%).
Linking resource matching and dispersal
We study theoretically the effect of inter-habitat migration on the distribution of population sizes between two habitats, and compare this distribution with the expected ideal free distribution (IFD). Whenever emigration from the two habitats is asymmetric, or when there is a survival cost during migration, the resulting equilibrium distribution of population sizes deviates from the IFD. This res
Laser techniques in acoustically levitated micro droplets
Laser techniques were applied to an acoustically levitated droplet for remote investigation of the diameter, species concentration and temperature of the suspended droplet. To this end, the third and the fourth harmonic of a Nd:YAG laser were used for investigation of elastic, fluorescence and phosphorescence signals from the droplet. The droplet was seeded with thermographic phosphors and acetone
Nanoelectronic pulse generators based on gated resonant tunnelling diodes
We study the operation of a gated resonant tunnel diode placed in an oscillator tank circuit for application as a pulse generator. The gated diode is realized by a metal gate placed 30nm away from a resonant tunnelling double barrier heterostructure, where the gate is used to control the current of the tunnelling diode. A large signal model is developed for the gated resonant tunnelling diode and
Circulating enterolactone and prostate cancer risk: a Nordic nested case-control study.
The impact of working technique on physical loads - an exposure profile among newspaper editors
The aim of this study was to investigate the possible associations between working technique, sex, symptoms and level of physical load in VDU-work. A study group of 32 employees in the editing department of a daily newspaper answered a questionnaire, about physical working conditions and symptoms from the neck and the upper extremities. Muscular load, wrist positions and computer mouse forces were