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Abstract: Lattice QCD is widely considered the correct theory of the strong force and is able to make quantitative statements in the low energy regime where perturbation theory is not applicable. The partition function of lattice QCD can be mapped onto a statistical mechanics system which then allows for the use of calculational methods such as Monte Carlo simulations. In recent years, the enormous success of GPU programming has also arrived at the lattice community. In this article, we give a short overview of Lattice QCD and motivate this need for large computing power. In our simulations we concentrate on a specific fermionic discretization, so-called Neuberger-Dirac fermions, which respect an exact chiral symmetry. We will discuss the algorithms we use in our GPU implementation which turns out to be an order of magnitude faster then the conventional CPU-equivalent. As an application we present results on the eigenvalue spectra in QCD and compare them to analytical calculations from Random Matrix Theory.

Lattice QCD is widely considered the correct theory of the strong force and is able to make quantitative statements in the low energy regime where perturbation theory is not applicable. The partition function of lattice QCD can be mapped onto a statistical mechanics system which then allows for the use of calculational methods such as Monte Carlo simulations. In recent years, the enormous success of GPU programming has also arrived at the lattice community. In this article, we give a short overview of Lattice QCD and motivate this need for large computing power. In our simulations we concentrate on a specific fermionic discretization, so-called Neuberger-Dirac fermions, which respect an exact chiral symmetry. We will discuss the algorithms we use in our GPU implementation which turns out to be an order of magnitude faster then the conventional CPU-equivalent. As an application we present results on the eigenvalue spectra in QCD and compare them to analytical calculations from Random Matrix Theory.

Abstract: Lattice simulations of QCD have produced precise estimates for the masses of the lowest-lying hadrons which show excellent agreement with experiment. By contrast, lattice results for the vector and axial vector form factors of the nucleon show significant deviations from their experimental determination. We present results from our ongoing project to compute a variety of form factors with control over all systematic uncertainties. In the case of the pion electromagnetic form factor we employ partially twisted boundary conditions to extract the pion charge radius directly from the linear slope of the form factor near vanishing momentum transfer. In the nucleon sector we focus specifically on the possible contamination from contributions of higher excited states. We argue that summed correlation functions offer the possibility of eliminating this source of systematic error. As an illustration of the method we discuss our results for the axial charge, g A , of the nucleon.

Lattice simulations of QCD have produced precise estimates for the masses of the lowest-lying hadrons which show excellent agreement with experiment. By contrast, lattice results for the vector and axial vector form factors of the nucleon show significant deviations from their experimental determination. We present results from our ongoing project to compute a variety of form factors with control over all systematic uncertainties. In the case of the pion electromagnetic form factor we employ partially twisted boundary conditions to extract the pion charge radius directly from the linear slope of the form factor near vanishing momentum transfer. In the nucleon sector we focus specifically on the possible contamination from contributions of higher excited states. We argue that summed correlation functions offer the possibility of eliminating this source of systematic error. As an illustration of the method we discuss our results for the axial charge, gA, of the nucleon.

We report a case in which STR typing failed to identify the minor component of a mixed saliva stain, but a mitochondrial restriction analysis succeeded in discriminating between the two components. To identify the nt16093 and nt16265 transitions, the template was amplified with the mismatch primers L16092-mm16085 and H16266-mm16269. In the presence of the transitions the mismatch primers created a BsaB I and a Cac8 I restriction site, respectively. Subsequently, aliquots were restricted separately using the enzymes Cac8 I and BsaB I which clearly identified the minor stain component.

We report on determinations of the low-energy constants α5and α8in the effective chiral Lagrangian at O(p4), using lattice simulations with Nf=2 flavours of dynamical quarks. Precise knowledge of these constants is required to test the hypothesis whether or not the up-quark is massless. Our results are obtained by studying the quark mass dependence of suitably defined ratios of pseudoscalar meson masses and matrix elements. Although comparisons with an earlier study in the quenched approximation reveal small qualitative differences in the quark mass behaviour, numerical estimates for α5and α8show only a weak dependence on the number of dynamical quark flavours. Our results disfavour the possibility of a massless up-quark, provided that the quark mass dependence in the physical three-flavour case is not fundamentally different from the two-flavour case studied here.

Plasminogen activators as inducible extracellular serine proteases are involved in a variety of processes, such as the degradation of brain structures. In regions of brain degradation, an increase in the expression of genes encoding cytokines and proteinases has recently been demonstrated. We tested the hypothesis, whether the plasminogen activator system as well as the Plasminogen activator inhibitors are expressed and possibly involved in a proteolytic cascade that breaks down the extracellular matrix as a result of ischemic or posttraumatic brain destructions. To study this supposition, we investigated immunohistochemically the expression of tPA, uPA and its receptor, the plasminogen activator inhibitors PAI-1 and PAI-2, tetranectin as well as the laminin breakdown as an event of secondary brain injury. Brain tissue from 21 autopsy cases with severe brain injuries, material from 14 ischemic infarcts and 11 controls with acute hypoxia were used. All components of the plasminogen activator system studied were overexpressed immunohistochemically in reactive astrocytes, microglia and endothelial cells around the lesion zone. Tetranectin showed an analogous distribution to the plasminogen activator system. A reduced immunoreactivity of laminin within the identical region of destruction was detected concomitant with laminin remnants in perivascular macrophages, so that a remarkable role of the plasmin cascade in the degradation of extracellular matrix proteins in the brain is taken into consideration.

We calculate the masses of the low-lying states with quantum numbers J^P^C = 0^+^+, 1^-^- in the Higgs and confinement regions of the three-dimensional SU(2) Higgs model, which plays an important role in the description of the thermodynamic properties of the standard model at finite temperatures. We extract the masses from correlation functions of gauge-invariant operators which are calculated by means of a lattice Monte Carlo simulation. The projection properties of our lattice operators onto the lowest states are greatly improved by the use of smearing techniques. We also consider cross correlations between various operators with the same quantum numbers. From these the mass eigenstates are determined by means of a variational calculation. In the symmetric phase, we find that some of the ground-state masses are about 30% lighter than those reported from previous simulations. We also obtain the masses of the first few excited states in the symmetric phase. Remarkable among these is the occurrence of a 0^+^+ state composed almost entirely of gauge degrees of freedom. The mass of this state, as well as that of its first excitations, is nearly identical to the corresponding glueball states in three-dimensional SU(2) pure gauge theory, indicating an approximate decoupling of the pure gauge sector from the Higgs sector of the model. We perform a detailed study of finite-size effects and extrapolate the lattice mass spectrum to the continuum.

Some critical points of the Hansen method for CEA determination are presented, and an automatical dialysis unit is described. Forty-three of 82 patients with colorectal carcinoma were studied four, eight, and fourteen days, and three and six months after surgery. In 61 (52.5%) the CEA level was higher than 2.5 ng/ml. Multiple variance analysis showed a significant dependence of CEA levels on the Dukes classification. After surgery, different slopes were seen in the decrease of CEA levels. Several months before its clinical detection, recurrent disease could be recognized by a renewed increase of CEA values. Interestingly, in one patient with liver metastases who initially had normal CEA values, a high CEA level was found 11 months later, when the disease was generalized.

This study was designed to test the effects of exposures to SO2at a level of 0.5 ppm for 3 h (present level for secondary standards) on the pulmonary function of normal, nonsmoking subjects and of patients with a history of mild to moderate asthma but with no recent exacerbations. Ten lung function tests were applied; five were of the so-called “sensitive type”. During control periods, all subjects were exposed to ambient air for the full 3-h period. Double-blind procedures were used.

Zusammenfassung In der präoperativen Funktionsdiagnostik der Lungenchirurgie kommt der Beurteilung des rechten Herzens und kleinen Kreislaufs hohe Bedeutung zu. Herzkatheterismus und selektive Angiographie der Lungengefäße wurden zur Bestimmung der funktionellen Ausgangslage herangezogen. Auf ihre Technik und ihre Bedeutung wird im einzelnen eingegangen. Ihr Beitrag zur Indikationsstellung zum operativen Eingriff wird an Hand eigener kasuistischer Mitteilungen erläutert.

Post-mortem CT-angiography is a valuable addition to post mortem diagnostics due to its ability to reliably discover discrete vascular pathologies. While different approaches are being pursued across the world, the need for validation and standardization of the method increases in order to facilitate its transition into daily routine. With this aim, an international working group has been performing a prospective multicenter study to validate the technique, define its indications and evaluate its advantages and limitations, especially compared to conventional autopsy.