An isotope labeling strategy for quantifying the degree of phosphorylation at multiple sites in proteins

A procedure for determining the extent of phosphorylation at individual sites of multiply phosphorylated proteins was developed and applied to two polyphosphorylated proteins. The protocol, using simple chemical (Fischer methyl-esterification) and enzymatic (phosphatase) modification steps and an accessible isotopic labeling reagent (methyl alcohol-d(4)), is described in detail. Site-specific phosphorylation stoichiometries are derived from the comparison of chemically identical but isotopically distinct peptide species analyzed by microspray liquid chromatography-mass spectrometry (microLC-MS) using a Micromass Q-TOF2 mass spectrometer. Ten phosphorylation sites were unambiguously identified in tryptic digests of both proteins, and phosphorylation stoichiometries were determined for eight of the ten sites using the isotope-coded strategy. The extent of phosphorylation was also estimated from the mass spectral peak areas for the phosphorylated and unmodified peptides, and these estimates, when compared with stoichiometries determined using the isotope-coded technique, differed only marginally (within approximately 20%).     

The dynamics and kinematics of the electron transfer reactions of CF[image omitted] with Ar

The electron transfer reactions between CF [image omitted] and Ar have been studied using a position-sensitive coincidence time-of-flight mass spectrometer. The spectra show the formation of CF [image omitted], CF [image omitted] and CF [image omitted] ions, accompanied by Ar+ ions, by dissociative and non-dissociative electron transfer reactions. Analysis of the PSCO data shows that the CF [image omitted] and CF [image omitted] ions are formed by reactions of ground state CF [image omitted](2B2) ions. The CF [image omitted] product is formed in high lying vibrational states of its ground electronic state, just below the dissociation asymptote to [image omitted]. The formation of CF [image omitted] proceeds via a sequential mechanism, involving the population of highly excited vibrational levels of the ground electronic state of CF [image omitted] which dissociate to CF [image omitted](2A1) + F when the CF [image omitted] is well separated from the Ar+ ion. No evidence of complexation is observed. The energy dependence of the experimental yield of the CF+ ion is consistent with it arising from a reaction of an electronic excited state of CF [image omitted], as proposed in a previous study of this collision system. The unimolecular dissociation of the reactant dications is also observed and indicates that these ions are predominantly in their ground (2B2) electronic state. The kinetic energy release of this unimolecular reaction indicates the metastable well of the CF [image omitted](2B2) state is approximately 3 eV deep and also shows that CF [image omitted](2B2) ions well below the barrier to charge separation can dissociate on the time-scale of the experiment. This observation implicates predissociation, possibly via a repulsive dication state, as the mechanism for the unimolecular charge separation of the ground state of CF [image omitted].     

Multiphoton lithography of nanocrystalline platinum and palladium for site-specific catalysis in 3D microenvironments

Integration of catalytic nanostructured platinum and palladium within 3D microscale structures or fluidic environments is important for systems ranging from micropumps to microfluidic chemical reactors and energy converters. We report a straightforward procedure to fabricate microscale patterns of nanocrystalline platinum and palladium using multiphoton lithography. These materials display excellent catalytic, electrical, and electrochemical properties, and we demonstrate high-resolution integration of catalysts within 3D defined microenvironments to generate directed autonomous particle and fluid transport.     

The FT-IR study of the brain tissue of Labeo rohita due to arsenic intoxication

The brain is believed to be particularly vulnerable to arsenic due to its high oxygen consumption rate and high level of polyunsaturated fatty acids and relatively high rate of oxygen free radical generate without commensurable level of arsenic. Hence, in the present work an attempt is made to study the changes in the biochemical contents in the brain tissues of edible fish Labeo rohita due to arsenic intoxication using Fourier Transform Infrared (FT-IR) spectroscopy. FT-IR spectra reveal significant differences in absorbance intensities between the control and arsenic intoxicated brain tissues, reflecting an alteration on the major biochemical constituents, such as lipids, proteins and nucleic acids of the brain tissues of L. rohita due to arsenic intoxication. Further, the administration of antidote DMSA improves the protein and lipid contents significantly in the brain tissues when compared to arsenic intoxicated tissues. The decrease in α-helix structure due to arsenic intoxication might be responsible for the increase in β-sheet secondary structures, which is consistent with the mechanism of β-sheet formation.     

Planning sustainable community health schemes in rural areas of developing countries

In this research, we consider the planning of community health schemes by non-governmental or faith-based organisations in rural areas of developing countries, from both top-down and ground level viewpoints. We conclude that both types of planning approach are valid and necessary for sustainability of such developments. With top-down planning in mind, we describe our hierarchical models especially designed for location of community health facilities, with objectives pertaining to both efficiency and equity of provision. As an additional case study, we present modelling of the location of a maximal number of self-sustainable primary healthcare workers in a rural region of India.     

Simultaneous spatial and spectral transparency in ultralong fiber lasers

We demonstrate that ultralong Raman lasers can be used to generate a transmission medium with simultaneous transparency over the spatial and the spectral domains. Numerical calculations show this cross-domain transparency to be preserved when the medium is used for transmitting high-intensity signals, which makes ultralong lasers an ideal experimental test bed for the study of multifrequency nonlinear interactions in optical fiber waveguides. Full spatiospectral transparency is experimentally obtained over a 20 nm x 20 km window.     

Zero-point plasmon motion in the extreme quantum limit in InSb

Further experiments at helium temperatures are described on the anomalous NMR relaxation peak, first reported by Bridges and Clark, in the extreme quantum limit in doped InSb, extending the previously reported density range of the phenomenon up to 5 × 10²² m^?3 of donor electrons. New features of the anomaly, in particular an isotope effect, are reported.The large density range over which the effect has now been observed, taken with the new features, render many of the previous theories of the peak untenable. Based on the zero-point plasmon motion of the electron gas, we put forward an interpretation which appears to explain the various aspects of the phenomenon.     

COMPOSITION OPERATOR ON BERS-TYPE SPACES

Necessary and sufficient conditions are established for a composition operator C f = fo to be bounded or compact on the Bers-type space Ha and the little Bers-type space Ha The boundedness and compactness of the composition operator C on A() are characterized, which generalize the case of C on Ha.