Saturn's open‐closed field line boundary:a Cassini electron survey at Saturn's magnetosphere

We investigate the average configuration and structure of Saturn's magnetosphere in the nightside equatorial and high‐latitude regions. Electron data from the Cassini Plasma Spectrometer's Electron Spectrometer (CAPS‐ELS) is processed to produce a signal‐to‐noise ratio for the entire CAPS‐ELS time of operation at Saturn's magnetosphere. We investigate where the signal‐to‐noise ratio falls below 1, to identify regions in the magnetosphere where there is a significant depletion in the electron content. In the nightside equatorial region we use this to find that the most planetward reconnection x‐line location is at 20 – 25 RS downtail from the planet in the midnight to dawn sector. We also find an equatorial dawn‐dusk asymmetry at a radial distance of >20 RS which may indicate the presence of plasma depleted flux tubes returning to the dayside after reconnection in the tail. Furthermore, we find that the high‐latitude magnetosphere is predominantly in a state of constant plasma depletion and located on open field lines. We map the region of high‐latitude magnetosphere that is depleted of electrons to the polar cap to estimate the size and open flux content within the polar caps. The mean open flux content for the northern and southern polar caps are found to be 25±5 and 32±5 GWb, respectively. The average location of the open‐closed field boundary is found at invariant colatitudes of 12.7±0.6° and 14.5±0.6°. The northern boundary is modulated by planetary period oscillations more than the southern boundary

A novel interaction between FlnA and Syk regulates platelet ITAM-mediated receptor signaling and function

Filamin A (FlnA) cross-links actin filaments and connects the Von Willebrand factor receptor GPIb-IX-V to the underlying cytoskeleton in platelets. Because FlnA deficiency is embryonic lethal, mice lacking FlnA in platelets were generated by breeding FlnAloxP/loxP females with GATA1-Cre males. FlnAloxP/y GATA1-Cre males have a macrothrombocytopenia and increased tail bleeding times. FlnA-null platelets have decreased expression and altered surface distribution of GPIbα because they lack the normal cytoskeletal linkage of GPIbα to underlying actin filaments. This results in ∼70% less platelet coverage on collagen-coated surfaces at shear rates of 1,500/s, compared with wild-type platelets. Unexpectedly, however, immunoreceptor tyrosine-based activation motif (ITAM)- and ITAM-like–mediated signals are severely compromised in FlnA-null platelets. FlnA-null platelets fail to spread and have decreased α-granule secretion, integrin αIIbβ3 activation, and protein tyrosine phosphorylation, particularly that of the protein tyrosine kinase Syk and phospholipase C–γ2, in response to stimulation through the collagen receptor GPVI and the C-type lectin-like receptor 2. This signaling defect was traced to the loss of a novel FlnA–Syk interaction, as Syk binds to FlnA at immunoglobulin-like repeat 5. Our findings reveal that the interaction between FlnA and Syk regulates ITAM- and ITAM-like–containing receptor signaling and platelet function

Oil Market Analysis for Teal

The goal of our project was to identify key economic indicators that have a significant influence on the price of oil per barrel. We identified five key indicators: Change in Inventory, OPEC Policy, GDP, Rig Count, Social/Environmental Factors. We used SPSS to build a linear multi-regression model between the dependent variable (price of oil) and the five indicators. We identified statistically significant variables and examined multiple scenarios in respective case of fluctuations in social/environmental factors and OPEC policy