A measurement of the energy spectra of cosmic rays from 20 to 1000 GeV per AMU

During the report period the BUGS-4 instrument was completed, and the maiden voyage took place on 29 September from Fort Sumner, New Mexico. The successful flight of a large spherical drift chamber is a unique first for the sub-orbital balloon program. Unfortunately the instrument was consumed by fire after striking a power line during landing. However, while at float altitude, circa 24 hours of data were telemetered. The pre-flight preparations, and flight operations are described

Historical reconstruction of the Atlantic Meridional Overturning Circulation from the ECMWF operational ocean reanalysis

A reconstruction of the Atlantic Meridional Overturning Circulation (MOC) for the period 1959–2006 has been derived from the ECMWF operational ocean reanalysis. The reconstruction shows a wide range of time-variability, including a downward trend. At 26N, both the MOC intensity and changes in its vertical structure are in good agreement with previous estimates based on trans-Atlantic surveys. At 50N, the MOC and strength of the subpolar gyre are correlated at interannual time scales, but show opposite secular trends. Heat transport variability is highly correlated with the MOC but shows a smaller trend due to the warming of the upper ocean, which partially compensates for the weakening of the circulation. Results from sensitivity experiments show that although the time-varying upper boundary forcing provides useful MOC information, the sequential assimilation of ocean data further improves the MOC estimation by increasing both the mean and the time variability

Cosmic Ray Energy Determination by the Reduced-Opening Angle Method

Accurate measurement of the primary galactic cosmic ray species energy dependence in the regime beyond approx. 500 GeV/a is difficult due to the low flux and the limitations of energy measurement techniques. However, such observations are essential to resolve several questions of current interest such as: Is the enrichment of heavy species (Z greater that or equal to 6) cosmic rays first reported at higher energies by the proton satellite' and then later at lower energies real? The results from a previous deployment of the reduced opening angle technique are inconclusive but the authors do point to limitations in the previous techniques. Another intriguing puzzle is the energy dependence of silicon cosmic rays. Two independent experiments using different experimental techniques indicate that silicon is under-abundant. At present the observation is limited by statistics; it could still be a three sigma fluctuation. However, if confirmed the current models of acceleration and propagation which are species independent are seriously inadequate. To progress further the species and energy dependence must be accurately measured in a manner that is free from systematic uncertainty. In this report we show that the reduced opening angle method offers a simple and relatively inexpensive method to answer these questions. First we present the physics of the reduced opening angle and indicate the expected energy and charge resolution. The proposed detector design is then presented followed by the expected performance. Where ever possible simple phenomenological expressions that allow 'back of the envelope' estimates are given. More details are presented in the appendices. The limit of the energy resolution and the expected event rates for iron cosmic rays are calculated. Salient points are summarized in the conclusions

Shock temperatures of SiO_2 and their geophysical implications

The temperature of SiO_2 in high-pressure shock states has been measured for samples of single-crystal α-quartz and fused quartz. Pressures between 60 and 140 GPa have been studied using projectile impact and optical pyrometry techniques at Lawrence Livermore National Laboratory. Both data sets indicate the occurrence of a shock-induced phase transformation at ∼70 and ∼50 GPa along the α- and fused quartz Hugoniots, respectively. The suggested identification of this transformation is the melting of shock-synthesized stishovite, with the onset of melting delayed by metastable superheating of the crystalline phase. Some evidence for this transition in conventional shock wave equation of state data is given, and when these data are combined with the shock temperature data, it is possible to construct the stishovite-liquid phase boundaries. The melting temperature of stishovite near 70 GPa pressure is found to be 4500 K, and melting in this vicinity is accompanied by a relative volume change and latent heat of fusion of ∼2.7% and ∼2.4 MJ/kg, respectively. The solid stishovite Hugoniot centered on α-quartz is well described by the linear shock velocity-particle velocity relation, u_s = 1.822 up + 1.370 km/s, while at pressures above the melting transition, the Hugoniot centered on α-quartz has been fit with u_s = 1.619 u_p + 2.049 km/s up to a pressure of ∼200 GPa. The melting temperature of stishovite near 100 GPa suggests an approximate limit of 3500 K for the melting temperature of SiO_2-bearing solid mantle mineral assemblages, all of which are believed to contain Si^(4+) in octahedral coordination with O^(2−). Thus 3500 K is proposed as an approximate upper limit to the melting point and the actual temperature in the earth's mantle. Moreover, the increase of the melting point of stishovite with pressure at 70 GPa is inferred to be ∼11 K/GPa. Using various adiabatic temperature gradients in the earth's mantle and assuming creep is diffusion controlled in the lower mantle, the current results could preclude an increase of viscosity by more than a factor of 10^3 with depth across the mantle

The Solubility of Potassium Permanganate.

n/

β2 Integrin CD11d/CD18: From Expression to an Emerging Role in Staged Leukocyte Migration

CD11d/CD18 is the most recently discovered and least understood β2 integrin. Known CD11d adhesive mechanisms contribute to both extravasation and mesenchymal migration – two key aspects for localizing peripheral leukocytes to sites of inflammation. Differential expression of CD11d induces differences in monocyte/macrophage mesenchymal migration including impacts on macrophage sub-set migration. The participation of CD11d/CD18 in leukocyte localization during atherosclerosis and following neurotrauma has sparked interest in the development of CD11d-targeted therapeutic agents. Whereas the adhesive properties of CD11d have undergone investigation, the signalling pathways induced by ligand binding remain largely undefined. Underlining each adhesive and signalling function, CD11d is under unique transcriptional control and expressed on a sub-set of predominately tissue-differentiated innate leukocytes. The following review is the first to capture the nearly three decades of CD11d research and discusses the emerging role of CD11d in leukocyte migration and retention during the progression of a staged immune response

CD11d integrin blockade reduces the systemic inflammatory response syndrome after spinal cord injury

Traumatic injury to the spinal cord triggers a systemic inflammatory response syndrome (SIRS), in which inflammatory cells from the circulation invade organs such as the liver, lung and kidney, leading to damage of these organs. Our previous study (Gris, et al, Exp. Neurol, 2008) demonstrated that spinal cord injury (SCI) activates circulating neutrophils that then invade the lung and kidney from 2 to 24. h after injury, increasing myeloperoxidase activity, cyclooxygenase-2 and matrix metalloproteinase-9 expression and lipid peroxidation in these organs. The present study was designed to ascertain whether a treatment that limits the influx of leukocytes into the injured spinal cord would also be effective in reducing the SIRS after SCI. This treatment is intravenous delivery of a monoclonal antibody (mAb) against the CD11d subunit of the CD11d/CD18 integrin expressed by neutrophils and monocytes. We delivered the anti-CD11d mAb at 2. h post moderate clip compression SCI at the 4th or 12th thoracic segments and assessed inflammation, oxidative activity and cellular damage within the lung, kidney and liver at 12. h post-injury. In some analyses we compared high and low thoracic injuries to evaluate the importance of injury level on the intensity of the SIRS. After T4 injury, treatment with the anti-integrin mAb reduced the presence of neutrophils and macrophages in the lung, with associated decreases in expression of NF-κB and oxidative enzymes and in the concentration of free radicals in this organ. The treatment also reduced lipid peroxidation, protein nitration and cell death in the lung. The anti-CD11d treatment also reduced the inflammatory cells within the kidney after T4 injury, as well as the free radical concentration and amount of lipid peroxidation. In the liver, the mAb treatment reduced the influx of neutrophils but most of the other measures examined were unaffected by SCI. The inflammatory responses within the lung and kidney were often greater after T4 than T12 injury. Clinical studies show that SIRS, with its associated organ failure, contributes significantly to the morbidity and mortality of SCI patients. This anti-integrin treatment may block the onset of SIRS after SCI. © 2011 Elsevier Inc