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In this work X-ray and elastic backscattered spectra from Pt and Bi thin targets were simultaneously measured using C-4, C-3+ ions in the energy range 2.5 MeV to 5 MeV. M alpha beta, M gamma and total M-shell X-ray production cross sections were extracted from collected X-ray and backscattered particle spectra using calibrated SDD X-ray and silicon solid state particle detectors. The obtained cross section values are compared to theoretical values employing commonly used datasets for fluorescence yields, emission rates, Coster-Kronig transitions and M- shell ionization cross sections based on the Semi-classical Approximation (United Atom and Separated Atom limits), PWBA (Plane Wave Born approximation), and ECPSSR models. The ISICS code was used for PWBA and ECPSSR calculations.

Background The time course and extent of recovery after revascularization of viable dysfunctional myocardium are variable. Although fibrosis is a major determinant, myocyte structural and molecular remodeling may also play important roles. Objectives This study sought to determine whether persistent myocyte loss and/or irreversibility of protein changes that develop in hibernating myocardium have an impact on functional recovery in the absence of infarction. Methods Swine implanted with a chronic left anterior descending artery (LAD) stenosis to produce hibernating myocardium underwent percutaneous revascularization, with serial functional recovery evaluated for 1 month (n = 12). Myocardial tissue was evaluated to assess myocyte size, nuclear density, and proliferation indexes in comparison with those of normal animals and nonrevascularized controls. Proteomic analysis by 2-dimensional differential in-gel electrophoresis was used to determine the reversibility of molecular adaptations of hibernating myocytes. Results At 3 months, physiological features of hibernating myocardium were confirmed, with depressed LAD wall thickening and no significant infarction. Revascularization normalized LAD flow reserve, with no immediate change in LAD wall thickening. Regional LAD wall thickening slowly improved but remained depressed 1 month post–percutaneous coronary intervention. Surprisingly, revascularization was associated with histological evidence of myocytes re-entering the growth phase of the cell cycle and increases in the number of c-Kit+ cells. Myocyte nuclear density returned to normal, whereas regional myocyte hypertrophy regressed. Proteomic analysis demonstrated heterogeneous effects of revascularization. Up-regulated stress and cytoskeletal proteins normalized, whereas reduced contractile and metabolic proteins persisted. Conclusions Delayed recovery of hibernating myocardium in the absence of scar may reflect persistent reductions in the amounts of contractile and metabolic proteins. Although revascularization appeared to stimulate myocyte proliferation, the persistence of small immature myocytes may have contributed to delayed functional recovery.

International audience; Expansion of aquaculture has increased concern over its environmental impact. The composition of effluents from intensive aquaculture is well documented, but few data on extensive aquaculture are available. During 12 draining operations, 523 water samples were collected downstream from six extensively-managed fishponds in northeastern France. Study ponds had surface areas of 2–620 ha and were managed for production of Cyprinids and Percids. Concentrations of total suspended solids, total phosphorus, and Kjeldahl nitrogen in effluents from the ponds were greatest during the final stage of draining. Loads of phosphorus were higher than those reported for effluents of more intensive aquaculture ponds in the USA, but the source of the potential pollutants was catchments and sediment rather than feeds and fertilizer. It will be necessary to reduce the water drawdown rate during the fishing stage and possibly implement other best management practices to prevent the TSS concentration from exceeding 1 g/L. Effluent phosphorus loads were higher than those reported for more intensive aquaculture ponds, but the pollutant source was catchments rather than feeds and fertilizers.

Storage rings as the ESR and the future NESR in the FAIR project are unique tools to study the dynamics of electron-ion and ion-atom collisions in the realm of strong perturbations and short interaction times. A telling sign of the character of such collisions are the electrons emitted into the continuum. For high Z projectiles and low Z targets the projectile centred continuum is dominating. Precision studies of these electrons emitted in relativistic collisions thus are of paramount importance for an understanding of the ionization mechanisms active in transferring electrons into the continua. Forward electron spectroscopy thus appears to be the tool of choice. For high precision studies in collision spectroscopy of high Z projectiles we have implemented an imaging forward electron spectrometer into the ESR supersonic jet target zone. In combination with a reaction microscope to be implemented next this enables investigations of several fundamental processes ranging from kinematically complete studies of multiple ionization and (e, 2e) on ions to radiative and non-radiative electron transfer processes to the projectile continuum and for the first time kinematically complete measurements of the short-wavelength limit of the electron nucleus Bremsstrahlung. We report first results.

Background Hibernating myocardium develops inhomogeneity in myocardial sympathetic innervation with spontaneous sudden cardiac death (SCD) because of ventricular fibrillation (VF). The triggers and prodromal arrhythmias initiating SCD in this substrate are unknown. Methods Swine chronically instrumented with a proximal left anterior descending coronary artery stenosis underwent placement of an implantable telemetry unit capable of continuously recording digitized electrocardiogram and left ventricular pressure signals at 1 kHz in conscious unrestrained animals for periods of up to 5 months. Results Spontaneous SCD (n = 10) was initiated by a close-coupled premature ventricular contraction followed by ventricular tachycardia (VT) that degenerated into VF during brief sympathetic activation. Peak heart rates were similar in animals that developed SCD vs survivors (250 ± 12 vs 261 ± 6 bpm). Electrocardiogram evidence of ischemia preceding VT/VF occurred in only 1 animal, and there was no significant infarction. Conclusions Spontaneous VT/VF in hibernating myocardium develops during brief sympathetic activation with only rare evidence of acute ischemia. This supports the notion that the regional remodeling accompanying hibernating myocardium may be a novel substrate for the development of SCD in chronic ischemic heart disease.

With the advanced accelerator technologies used at the SIS/ESR heavy ion facility at GSI, the highest charge states (bare, H-like, etc.) even for the heaviest ions can be provided for experiments at moderate collision velocities (vion

A crystal spectrometer has been constructed in the Focusing Compensated Asymmetric Laue geometry covering the energy range between 30 and 120 keV. We summarize the crystal optics and show the usefulness of the instrument for spectroscopy of stationary and fast moving X-ray sources. Results are reported from several tests employing a 169 Yb gamma-ray source and the Lyman radiation of one-electron Au 78+ ions travelling at a velocity corresponding to β = v / c o ≈0.44.

The spectroscopy of atomic transitions in the hard X-ray regime above 15 keV utilizing position-sensitive solid state detectors is discussed. Special emphasis is given to the current detector developments for X-ray spectroscopy of heavy ions at the ESR storage ring where applications for precision spectroscopy as well as for polarization studies are of particular interest. For both cases, the advantages and new possibilities which are opened up by position and energy resolving solid state detectors are illustrated by the presentation of first experiments.

The results of a numerical simulation, performed to check the validity of a method developed for reconstruction of concentration distributions truncated by the detection limit, are reported in the context of trace element analysis in biomedical samples by total-reflection X-ray fluorescence. This method, by correcting a distribution over the whole range of concentrations in a population of samples, restores a number of measurements reporting results below the detection limit. We show by Monte Carlo simulations, assuming lognormal distributions to describe both the concentrations measured as well as the detection limits in the biomedical samples, that the method developed is accurate to within 5% for most typical situations. Moreover, we demonstrate that the factor limiting the accuracy of the correction is the number of measurements, not the correction procedure itself. We have found in simulations that the reconstruction of a concentration distribution, for a typical population size of N =100, is possible when the concentrations are measured only in 20–30% of samples. On the other hand, we show that by ignoring the truncation of a concentration distribution by the detection limit, the results can be systematically biased by as much as 50%. The method developed is applied to the analysis of trace elements in human breast tissue samples by total-reflection X-ray fluorescence (TXRF). The results are also discussed in terms of the size of the population studied.