Particle size distribution of suspended solids in the Chesapeake Bay entrance and adjacent shelf waters

Characteristics of suspended solids, including total suspended matter, total suspended inorganics, total suspended organics, particle size distribution, and the presence of the ten most prominent particle types were determined. Four research vessels simultaneously collected samples along four transects. Samples were collected within a 2-hour period that coincided with the maximum ebb penetration of Chesapeake Bay outwelling. The distribution of primary and secondary particle size modes indicate the presence of a surface or near-surface plume, possibly associated with three sources: (1) runoff, (2) resuspension of material within the Bay, and/or (3) resuspension of material in the area of shoals at the Bay mouth. Additional supportive evidence for this conclusion is illustrated with ocean color scanner data

The DE magnetometer preprocessor users guide

A users guide for the Dynamics Explorer magnetometer preprocessor computer program is provided. This program is written in Xerox Extended FORTRAN IV and is used to process telemetry data in order to provide data files for use in analysis programs. This preprocessor is designed to operate on the Sigma 9 and the IBM 4341

A non-Gaussian landscape

Primordial perturbations with wavelengths greater than the observable universe shift the effective background fields in our observable patch from their global averages over the inflating space. This leads to a landscape picture where the properties of our observable patch depend on its location and may significantly differ from the expectation values predicted by the underlying fundamental inflationary model. We show that if multiple fields are present during inflation, this may happen even if our horizon exit would be preceded by only a few e-foldings of inflation. Non-Gaussian statistics are especially affected: for example models of local non-Gaussianity predicting |f_NL|>> 10 over the entire inflating volume can have a probability up to a few tens of percent to generate a non-detectable bispectrum in our observable patch |fNL^{obs.}|<10. In this work we establish systematic connections between the observable local properties of primordial perturbations and the global properties of the inflating space which reflect the underlying high energy physics. We study in detail the implications of both a detection and non-detection of primordial non-Gaussianity by Planck, and discover novel ways of characterising the naturalness of different observational configurations

The Role of NADPH Oxidase in the Modulation of PP2A

Transient, but severe global ischemia results in AMPA receptor (AMPAR) mediated delayed neuronal death (DND). AMPARs, a major glutamatergic receptor in the CNS, are heteromeric complexes composed of GluA1 - GluA4 subunits. Most AMPARs in the hippocampus are calcium-impermeable due to the presence of the edited form of the GluA2 subunit. Ischemia results in a down-regulation of GluA2 mRNA and protein expression, resulting in the expression of GluA2- lacking, calcium/zinc-permeable AMPARs. It has been indicated that these GluA2-lacking AMPARs play a key role in promoting DND following ischemic injury. Recent studies report that an oxidative stress signaling pathway is responsible for the ischemia/reperfusion-induced changes in AMPAR subunit composition. Studies suggest that NADPH oxidase, a superoxide generator, is the source that initiates the oxidative stress-signaling cascade during post-ischemic reperfusion. We observed that inhibition of reactive oxygen species (ROS) generated by mitochondria and xanthine oxidase failed to diminish the oxygen-glucose deprivation/ reperfusion (OGD/R)-induced degradation of GluA2. However, inhibition of NADPH oxidase did diminish the OGD/R-induced degradation of GluA2, supporting a role for NADPH oxidase in the oxidative stress-signaling cascade. We also demonstrated that the treatment of acute adult rat hippocampal slices to OGD/R results in the sustained activation of PKCα and sustained Ser880 phosphorylation of GluA2, priming the subunit for internalization. Inhibition of NADPH oxidase resulted in a decrease in activated PKCα and Ser880 phosphorylation of GluA2. The objective of this study was to investigate the role of NADPH oxidase in modulating PKCα activity. PKCα activity is positively regulated by increases in calcium, therefore any enhancement in calcium concentrations will increase PKCα activity. Oxidative stress and NADPH oxidase activity have been linked to effecting calcium levels, therefore, inhibition of NADPH oxidase activity during OGD/R could potentially dampen PKCα activity through the attenuation of oxidative stress-enhanced rises in calcium entry and intracellular calcium release necessary for PKCα activation. A second possibility is that PKCα may be redox sensitive and its activity could be increased with oxidative stress. A third possibility is that the phosphatases responsible for regulating PKCα activity may be attenuated by a NADPH oxidase-mediated signaling cascade. Here, we show that protein phosphatase 2A (PP2A), a phosphatase responsible for the dephosphorylation and inactivation of PKC, undergoes a NADPH oxidase-mediated increase in phosphorylation, which has been reported to inactivate the phosphatase. Collectively, these results identify a mechanism that may underlie the post-ischemic-induced degradation of the GluA2 subunit

Lava flow field emplacement studies of Mauna Ulu (Kilauea Volcano, Hawai'i, USA) and Venus, using field and remote sensing analyses

This work examines lava emplacement processes by characterizing surface units using field and remote sensing analyses in order to understand the development of lava flow fields. Specific study areas are the 1969-1974 Mauna Ulu compound flow field, (Kilauea Volcano, Hawai'i, USA), and five lava flow fields on Venus: Turgmam Fluctus, Zipaltonal Fluctus, the Tuli Mons/Uilata Fluctus flow complex, the Var Mons flow field, and Mylitta Fluctus.Lava surface units have been examined in the field and with visible-, thermal-, and radar-wavelength remote sensing datasets for Mauna Ulu, and with radar data for the Venusian study areas. For the Mauna Ulu flow field, visible characteristics are related to color, glass abundance, and dm- to m-scale surface irregularities, which reflect the lava flow regime, cooling, and modification due to processes such as coalescence and inflation. Thermal characteristics are primarily affected by the abundance of glass and small-scale roughness elements (such as vesicles), and reflect the history of cooling, vesiculation and degassing, and crystallization of the lava. Radar characteristics are primarily affected by unit topography and fracturing, which are related to flow inflation, remobilization, and collapse, and reflect the local supply of lava during and after unit emplacement. Mauna Ulu surface units are correlated with pre-eruption topography, lack a simple relationship to the main feeder lava tubes, and are distributed with respect to their position within compound flow lobes and with distance from the vent.The Venusian lava flow fields appear to have developed through emplacement of numerous, thin, simple and compound flows, presumably over extended periods of time, and show a wider range of radar roughness than is observed at Mauna Ulu. A potential correlation is suggested between flow rheology and surface roughness. Distributary flow morphologies may result from tube-fed flows, and flow inflation is consistent with observed surface characteristics. Furthermore, the significance of inflation at Mauna Ulu and comparison of radar characteristics indicates that inflation may, in fact, be more prevalent on Venus than at Mauna Ulu. Although the Venusian flow fields display morphologies similar to those observed within terrestrial flow fields, the Venusian flow units are significantly larger