A general introduction to the use of feed-back artificial neural networks (ANN) for obtaining good approximate solutions to combinatorial optimization problems is given, assuming no previous knowledge in the field. In particular we emphasize a novel neural mapping technique which efficiently reduces the solution space. This approach maps the problems onto Potts glass rather than spin glass models.

We propose an ac current source that can be tuned from a pure charge to a pure spin current source. The device consists of two mesoscopic capacitors attached to a two-dimensional strip of a topological insulator. The change from charge to spin current is controlled by an offset in the top gate potentials that drive the capacitors. In addition to this setup, which anticipates the experimental reali

Accurate quantitation of activity provides the basis for internal dosimetry of targeted radionuclide therapies. This study investigated quantitative imaging capabilities at sites with a variety of experience and equipment and assessed levels of errors in activity quantitation in Single-Photon Emission Computed Tomography (SPECT) and planar imaging. Participants from 9 countries took part in a comp

Protein Arp, the IgA-binding protein of the group A Streptococcus, has affinity for the Fc-part of IgA. The binding between protein Arp and several different molecular forms of human IgA was characterized. It was found that protein Arp bound with higher affinity to uncomplexed forms of IgA than to complexed forms (secretory IgA, alpha 1-antitrypsin-IgA and alpha 1-microglobulin-IgA). Thus, the aff

The current study aims to computationally evaluate the hemodynamic impact of a novel sealing mechanism employed by a recently developed endograft (Ovation TriVascular Stent-Graft System) for endovascular aneurysm repair. The exploitation of two inflatable O-rings to achieve sealing may be advantageous in terms of accommodating challenging anatomies, but comes at a price of a marked inflow stenosis

We evaluate the distribution of waiting times between electrons emitted by a driven mesoscopic capacitor. Based on a wave packet approach we obtain analytic expressions for the electronic waiting time distribution and the joint distribution of subsequent waiting times. These semi-classical results are compared to a full quantum treatment based on Floquet scattering theory and good agreement is fou

BACKGROUND: The available literature does not present a "gold standard" for post-operative pain treatment after total hip arthroplasty (THA). The aim of this prospective observational study was to explore and document post-operative pain treatment, including outcomes, in a large cohort of patients undergoing THA at five different Danish hospitals.METHODS: This prospective, multicentre, observation

The interaction potential V(Q2) between static test charges can be used to define an effective charge αv(Q2) and a physically based renormalization scheme for quantum chromodynamics and other gauge theories. In this paper we use recent results for finite-mass fermionic corrections to the heavy-quark potential at two loops to derive the next-to-Ieading order term for the Gell-Mann-Low function of t

For treatment of systemic malignancies, when external radiation therapy is not applicable, radionuclide therapy can be an alternative. In this form of therapy, radionuclides are administered to the patient, often in a form where the radionuclide is labelled to a molecule that plays the active part in the localization of the tumor. Since the aim is to impart lethal damage to tumor cells while maint

We present a new method for matching the two twin-processes gb → H±t and gg → H±tb in Monte Carlo event generators. The matching is done by defining a double-counting term, which is used to generate events that are subtracted from the sum of these two twin-processes. In this way we get a smooth transition between the collinear region of phase space, which is best described by gb → H ±t, and the ha

We calculate the potential between two static quarks in QCD using modified boundary conditions for the perturbative expansion. Through a change of the Feynman prescription we effectively add a "sea" of gluons to the asymptotic states with energies below a given scale A. We find that the standard result for the static potential gets corrections of order A 2/Q 2 both at small and large momentum tran

Membrane processes are often competing directly with conventional separation processes. The aim of this study is to highlight the potentials of combinations of membrane processes and conventional separation processes by the means of hybrid processes and process synergies. The concepts of hybrid processes and process synergies will be introduced and defined supported by industrial examples, e.g. th

We present a comprehensive study of the determination of the strong coupling from τ decay, using the most recent release of the experimental ALEPH data. We critically review all theoretical strategies used in previous works and put forward various novel approaches which allow one to study complementary aspects of the problem. We investigate the advantages and disadvantages of the different methods

The evolution of complex life over the past 600 million years was disrupted by at least five mass extinctions, one of which occurred at the close of the Triassic period. The end-Triassic extinction corresponds to a period of high atmospheric-CO 2 concentrations caused by massive volcanism and biomass burning; most extinction scenarios invoke the resulting environmental perturbations in accounting