Baryons and confining strings

The subleading term of the heavy quark potential (the analogue of the Luscher term) is computed in a string model for the case of three quarks. It turns out to be positive in 2+1 dimensions, making the potential non-concave as a function of the scale for fixed geometry. The results are compared to numerical simulations of the lattice gauge theory.Comment: Lattice2003(topology), 3 pages, 2 figure

More on Electric and Magnetic Fluxes in SU(2)

The free energies of static charges and center monopoles are given by their fluxes. While electric fluxes show the universal behaviour of the deconfinement transition, the monopole free energies vanish in the thermodynamic limit at all temperatures and are thus irrelevant for the transition. Magnetic fluxes may, however, be used to measure the topological susceptibility without cooling.Comment: 3 pages, LaTeX2e (ws-procs9x6.cls), 1 eps-figure, talk presented by L.v.S. at Quark Confinement and the Hadron Spectrum V, Gargnano, Italy, September 10-14, 200

Tracking and Tracing in Food Networks: The Case of the Feed Industry

This paper discusses an organisational framework for Tracking & Tracing and quality management in the agriculture and food network and thus providing increased transparency therein. The legal and market environments that especially European companies of the compound feeds sector face today is being analyzed with respect to resulting recent and present requirements. A technological solution for companies and supply chains that helps dealing with these requirements is presented with an organisational glance inside the QM-G system.Tracking & Tracing, Feed Industry, Inter-Organizational Information System QM-G, Agribusiness, Industrial Organization,

Deconfinement transition in 2+1-dimensional SU(4) lattice gauge theory

A missing piece is added to the Svetitsky-Yaffe conjecture. The spin model in the same universality class as the (2+1)d SU(4) theory, the 2d Ashkin-Teller model, has a line of continuously varying critical exponents. The exponents measured in the gauge theory correspond best to the Potts point on the Ashkin-Teller line.Comment: Lattice2003(topology), 3 pages, 5 figure

Symmetries of Discontinuous Flows and the Dual Rankine-Hugoniot Conditions in Fluid Dynamics

It has recently been shown that the maximal kinematical invariance group of polytropic fluids, for smooth subsonic flows, is the semidirect product of SL(2,R) and the static Galilei group G. This result purports to offer a theoretical explanation for an intriguing similarity, that was recently observed, between a supernova explosion and a plasma implosion. In this paper we extend this result to discuss the symmetries of discontinuous flows, which further validates the explanation by taking into account shock waves, which are the driving force behind both the explosion and implosion. This is accomplished by constructing a new set of Rankine-Hugoniot conditions, which follow from Noether's conservation laws. The new set is dual to the standard Rankine-Hugoniot conditions and is related to them through the SL(2,R) transformations. The entropy condition, that the shock needs to satisfy for physical reasons, is also seen to remain invariant under the transformations.Comment: 14 pages, 1 figur

Comprehensive comparison of in silico MS/MS fragmentation tools of the CASMI contest: database boosting is needed to achieve 93% accuracy.

In mass spectrometry-based untargeted metabolomics, rarely more than 30% of the compounds are identified. Without the true identity of these molecules it is impossible to draw conclusions about the biological mechanisms, pathway relationships and provenance of compounds. The only way at present to address this discrepancy is to use in silico fragmentation software to identify unknown compounds by comparing and ranking theoretical MS/MS fragmentations from target structures to experimental tandem mass spectra (MS/MS). We compared the performance of four publicly available in silico fragmentation algorithms (MetFragCL, CFM-ID, MAGMa+ and MS-FINDER) that participated in the 2016 CASMI challenge. We found that optimizing the use of metadata, weighting factors and the manner of combining different tools eventually defined the ultimate outcomes of each method. We comprehensively analysed how outcomes of different tools could be combined and reached a final success rate of 93% for the training data, and 87% for the challenge data, using a combination of MAGMa+, CFM-ID and compound importance information along with MS/MS matching. Matching MS/MS spectra against the MS/MS libraries without using any in silico tool yielded 60% correct hits, showing that the use of in silico methods is still important

The Polyakov Loop and its Relation to Static Quark Potentials and Free Energies

It appears well accepted in the literature that the correlator of Polyakov loops in a finite temperature system decays with the "average" free energy of the static quark-antiquark system, and can be decomposed into singlet and adjoint (or octet for QCD) contributions. By fixing a gauge respecting the transfer matrix, attempts have been made to extract those contributions separately. In this paper we point out that the "average" and "adjoint" channels of Polyakov loop correlators are misconceptions. We show analytically that all channels receive contributions from singlet states only, and give a corrected definition of the singlet free energy. We verify this finding by simulations of the 3d SU(2) pure gauge theory in the zero temperature limit, which allows to cleanly extract the ground state exponents and the non-trivial matrix elements. The latter account for the difference between the channels observed in previous simulations.Comment: 14 pages, 3 figures, 1 table; note and reference adde