The molecular dynamics simulation code ls1 mardyn is presented. It is a highly scalable code, optimized for massively parallel execution on supercomputing architectures, and currently holds the world record for the largest molecular simulation with over four trillion particles. It enables the application of pair potentials to length and time scales which were previously out of scope for molecular dynamics simulation. With an efficient dynamic load balancing scheme, it delivers high scalability even for challenging heterogeneous configurations. * To whom correspondence should be addressed † High Performance Computing Center Stuttgart (HLRS), Germany ‡ Laboratory of Engineering Thermodynamics (LTD), Univ. of Kaiserslautern, Germany ¶ Scientific Computing in Computer Science (SCCS), TU München, Germany § Thermodynamics and Energy Technology (ThEt), Univ. of Paderborn, Germany 1 Presently, multi-center rigid potential models based on Lennard-Jones sites, point charges and higher-order polarities are supported. Due to its modular design, ls1 mardyn can be extended to new physical models, methods, and algorithms, allowing future users to tailor it to suit their respective needs. Possible applications include scenarios with complex geometries, e.g.for fluids at interfaces, as well as non-equilibrium molecular dynamics simulation of heat and mass transfer.

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BACKGROUND AND PURPOSE: High-resolution carotid MR imaging can accurately identify complicated American Heart Association lesion type VI plaques, which are characterized by thrombus, hemorrhage, or a ruptured fibrous cap. The purpose of this study is to evaluate whether CTA can be used as screening tool to predict the presence or absence of American Heart Association lesion type VI plaques as defined by high-resolution MR imaging.

Nuclear reaction / Cross section / Thick target yield / Integral yield / Separation of positron emitter52 Mn / Ion exchange chromatography Summary. With respect to the production of no-carrieradded 52 Mn nuclear reactions on natural chromium were investigated. Cross sections of the reactions nat Cr( p, x) 48 V, 48,49,51 Cr, 52g,m Mn were determined in the proton energy range of 7.6 to 45 MeV. Additionally, production yields of 52g,m Mn and 51 Cr were measured in the energy range from 8.2 to 16.9 MeV and therefrom the calculated saturation thick target yields were obtained as (2.55 ± 0.31), (6.96 ± 0.57), and (1.53 ± 0.15) GBq/μA, respectively.For in vivo applications like PET, low toxicity is critical and sufficient activity of a radiolabelled compound mandatory. Thus, additional purification steps after separation of radionuclides and target materials have to be avoided. However, no isolation procedure has been reported in the literature so far where radiomanganese is directly obtained in a nonhazardous solution. Therefore a new separation procedure was developed utilizing the cation-exchange resin DOWEX 50W×8 (H + -form). 52g Mn was quantitatively isolated from "bulk" chromium after 3 to 4 h in non-hazardous 0.067 M ammonium citrate solution. Up to 99% of 52g Mn activity was harvested within 10 to 15 mL eluent solution with no measureable 51 Cr impurities.

Fifty-five patients were followed up for their state of fertility at a time varying in length after testicular torsion. In addition to the spermiogram they were screened for sperm antibodies. Biopsy samples were collected from the contralateral (not contorted) testis in 34 patients at the time of torsion or immediately afterwards. Two to 8 years after torsion only 7 out of 55 patients had a normal spermiogram. Nineteen had an OAT syndrome, 10 had asthenospermia and 19 had teratospermia. Sperm antibodies occurred very rarely at the time of torsion (2/36) or at the time of a further checkup (2/36). Immunological damage to the noncontorted testis by the contorted one seems therefore rather unlikely. Histology of the contralateral testis, the samples of which were taken at the time of torsion (30) or up to 4 months later (4), showed pathological conditions in 30/34 cases (desquamation of the germinative epithelium, atrophy of the Leydig cells, malformation of spermatoblasts) and normal spermiogenesis in 4 cases only. Hence, a preexistent congenital testicular dysplasia must be assumed to be the cause of the observed disturbance of spermiogenesis and reduced fertility.