Trees of Fusion Systems

We define a `tree of fusion systems' and give a sufficient condition for its completion to be saturated. We apply this result to enlarge an arbitrary fusion system by extending the automorphism groups of certain of its subgroups

Cumulant versus jet-like three-particle correlations

Two-particle jet-like azimuthal correlations have revealed intriguing modifications to the away-side of high pt trigger particles in relativistic heavy-ion collisions. Three-particle jet-like azimuthal correlation and three-particle azimuthal cumulant have been analyzed in experiments in attempt to distinguish conical emission of jet-correlated particles from other physics mechanisms. We investigate the difference between three-particle jet-like correlation and three-particle cumulant in azimuth. We show, under the circumstance where the away-side two-particle correlation is relatively flat in azimuth and similar in magnitude to the azimuthal average of the two-particle correlation signal, that the three-particle cumulant cannot distinguish conical emission from other physics mechanisms. The three-particle jet-like correlation, on the other hand, retains its discrimination power.Comment: 13 pages, 8 figures. published versio

G-Protein Coupled Receptor 18 Contributes to Establishment of the CD8 Effector T Cell Compartment.

The requirements for effector and memory CD8 T cell development are incompletely understood. Recent work has revealed a role for G-protein coupled receptor 18 (GPR18) in establishment of the intestinal CD8αα intraepithelial lymphocyte compartment. Here, we report that GPR18 is also functionally expressed in conventional CD8αβ T cells. When the receptor is lacking, mice develop fewer CD8+ KLRG1+ Granzyme B+ effector-memory cells. Bone marrow chimera studies show that the GPR18 requirement is CD8 T cell intrinsic. GPR18 is not required for T-bet expression in KLRG1+ CD8 T cells. Gene transduction experiments confirm the functional activity of GPR18 in CD8 T cells. In summary, we describe a novel GPCR requirement for establishment or maintenance of the CD8 KLRG1+ effector-memory T cell compartment. These findings have implications for methods to augment CD8 effector cell numbers

Electronic height indicator for agricultural machines

This paper addresses the design and development of a low cost electronic height indicator for a self-propelled spray rig. The prime objective is to give a spray rig operator an accurate indication of the boom height above the ground by using an electronic display in the tractor cabin to improve the efficiency of chemical application. This indicator is implemented using a microcontroller and a Hall-effect sensor. The field test proves that this indicator has improved the spraying performance by eliminating human error in estimating boom height, especially during night-time and dusty conditions

Effect of Fractional Kinetic Helicity on Turbulent Magnetic Dynamo Spectra

Magnetic field amplification in astrophysics ultimately requires an understanding of magnetohydrodynamic turbulence. Kinetic helicity has long been known to be important for large scale field growth in forced MHD turbulence, and has been recently demonstrated numerically to be asymptotically consistent with slow mean field dynamo action in a periodic box. Here we show numerically that the magnetic spectrum at and below the forcing scale is also strongly influenced by kinetic helicity. We identify a critical value, $f_{h,crit}$ above which the magnetic spectrum develops maxima at wavenumber $= 1$ scale {\it and} at the forcing scale, For $f< f_{h,crit}$ the field peaks only at the resistive scale. Kinetic helicity may thus be important not only for generating a large scale field, but also for establishing observed peaks in magnetic spectra at the forcing scale. The turbulent Galactic disk provides an example where both large scale ($>$ supernova forcing scale) fields and small scale ($\le$ forcing scale, with peak at forcing scale) fields are observed. We discuss this, and the potential application to the protogalaxy, but also emphasize the limitations in applying our results to these systems.Comment: version accepted to ApJL, 10 pages, 3 fig