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Abstract  Changes in microbial biomass and activity were determined in a sandy-loam soil treated with successive dosages of oxytetracycline (a bactericide) or captan (a fungicide) throughout 98 days of incubation under laboratory conditions. The numbers of culturable bacteria and fungi, total bacterial and fungal biomass (as amounts of phospholipid fatty acids, PLFA), the fungal/bacterial ratio, activities of acid and alkaline phosphatases and urease as well as concentrations of N-NH4 + and N-NO3 − were assessed. Both oxytetracycline and captan significantly decreased numbers of culturable bacteria whereas total bacterial biomass (bactPLFA) was not affected. Oxytetracycline did not effect on the fungal biomass, however their numbers were reduced after the first and second time of soil amendment with the bactericide. Conversely, fungal numbers and biomass (PLFA 18:2ω6,9) significantly decreased in response to soil treatment with the fungicide. Compared to oxytetracycline, captan significantly decreased activities of acid and alkaline phosphatases. For urease activity, the decreased activity was only observed in the soil after the third dosage of captan. Both biocides significantly increased concentrations of N-NH4 + and decreased concentrations of N-NO3 − after the soil treatments. The results of this study indicate that successive soil treatment with oxytetracycline or captan dosages may negatively affect non-target soil microorganisms and their activities. [ABSTRACT FROM AUTHOR]

Abstract  Experimental conclusions from air shower observations on cosmic-ray photons above 1019 eV are based on the comparison to detailed shower simulations. For the calculations, the photonuclear cross-section needs to be extrapolated over several orders of magnitude in energy. The uncertainty from the cross-section extrapolation translates into an uncertainty of the predicted shower features for primary photons and, thus, into uncertainties for a possible data interpretation. After briefly reviewing the current status of ultra-high energy photon studies, the impact of the uncertainty of the photonuclear cross-section for shower calculations is investigated. Estimates for the uncertainties in the main shower observables are provided. Photon discrimination is shown to be possible even for rapidly rising cross-sections. When photon-initiated showers are identi-ed, it is argued that the sensitivity of photon shower observables to the photonuclear cross-section can in turn be exploited to constrain the cross-section at energies not accessible at colliders. [ABSTRACT FROM AUTHOR]

Abstract  The electron and muon number of extensive air showers (EAS) measured at ground level are the main observables of the detector array of the KASCADE experiment. The two-dimensional frequency distribution of these observables is used for reconstructing the energy spectra of five elemental groups representing the chemical composition of primary cosmic rays in the energy range from 1015 eV to 1017 eV. The results of the presented unfolding analysis depend crucially on simulations of EAS, and therefore on the hadronic interaction models used for their generation. As it turns out, the results for the individual energy spectra show to be sensitive to the characteristics of the interaction model used. Furthermore, none of the models discussed (QGSJet and SIBYLL) is capable to describe the data consistently over the whole measurement range with discrepancies appearing in different energy regions. [ABSTRACT FROM AUTHOR]

Abstract  In this work, the relation between muon production in extensive air showers and features of hadronic multiparticle production at low energies is studied. Using CORSIKA, we determine typical energies and phase space regions of secondary particles which are important for muon production in extensive air showers and confront the results with existing fixed target measurements. Furthermore possibilities to measure relevant quantities of hadron production in existing and planned accelerator experiments are discussed. [ABSTRACT FROM AUTHOR]

Abstract  At high energy, cosmic rays can only be studied by measuring the extensive air showers they produce in the atmosphere of the Earth. Although the main features of air showers can be understood within a simple model of successive interactions, detailed simulations and a realistic description of particle production are needed to calculate observables relevant to air shower experiments. Currently hadronic interaction models are the main source of uncertainty of such simulations. We will study the effect of using different hadronic models available in corsika and conex on extensive air shower predictions. [ABSTRACT FROM AUTHOR]

Abstract  KASCADE-Grande is a multi-detector setup to get redundant information on single air shower basis. The information is used to perform multi-parameter analyses to solve the threefold problem of the reconstruction of the unknown primary energy, the primary mass, and to quantify the characteristics of the hadronic interactions in the air-shower development. This contribution discusses the various ways of testing the hadronic interaction mechanisms with data of the original KASCADE experiment and their results, as well as the capabilities in testing the models with the extension of KASCADE, the KASCADE-Grande experiment. Though no hadronic interaction model is fully able to describe the multi-parameter data of KASCADE consistently, the more recent models or improved versions of older models reproduce the data better than a few years ago. [ABSTRACT FROM AUTHOR]

Background. The aim was to systematically integrate the available evidence on psychosocial and demographic factors associated with response prediction to prophylactic lithium.Method. Each psychosocial or demographic variable that was related to lithium response in at least one study was examined with respect to response prediction. If several studies were located for the same variable results were integrated using a meta-analytical approach. To account for heterogeneity of primary studies aggregation of results was based on a random-effects model.Results. Out of 27 psychosocial and demographic variables investigated in this review, nine variables were identified as significantly related to outcome under to prophylactic lithium: (1) high social status, (2) social support, (3) good compliance, and (4) dominance may be protective against a recurrence under lithium. In contrast, (5) stress, (6) high expressed emotions, (7) neurotic personality traits, (8) unemployment, and (9) a high number of life events were identified as possible risk factors for poor response.Conclusions. This systematic review shows a surprisingly high number of psychosocial variables to be related to lithium response. Effect sizes were, however, small to moderate. Many variables should, therefore, be considered simultaneously to predict response. [ABSTRACT FROM AUTHOR]

We present the results of the search for large-scale anisotropies in the arrival directions of cosmic rays performed with the KASCADE-Grande experiment at energies higher than eV. To eliminate spurious anisotropies due to atmospheric or instrumental effects we apply the east–west method. We show, using the solar time distribution of the number of counts, that this technique allow us to remove correctly the count variations not associated to real anisotropies. By applying the east–west method we obtain the distribution of number of counts in intervals of 20 minutes of sidereal time. This distribution is then analyzed by searching for a dipole component; the significance of the amplitude of the first harmonic is 3.5σ, therefore, we derive its upper limit. The phase of the first harmonic is determined with an error of a few hours and is in agreement with the measurements obtained in the 1014 < E < 2 × 1015 eV energy range by the EAS-TOP, IceCube, and IceTop experiments. This supports the hypothesis of a change of the phase of the first harmonic at energies greater than ∼2 × 1014 eV. [ABSTRACT FROM AUTHOR]

KASCADE and KASCADE-Grande were multi-detector installations to measure individual air showers of cosmic rays at ultra-high energy. Based on data sets measured by KASCADE and KASCADE-Grande, 90% C.L. upper limits to the flux of gamma-rays in the primary cosmic ray flux are determined in an energy range of eV. The analysis is performed by selecting air showers with a low muon content as expected for gamma-ray-induced showers compared to air showers induced by energetic nuclei. The best upper limit of the fraction of gamma-rays to the total cosmic ray flux is obtained at eV with . Translated to an absolute gamma-ray flux this sets constraints on some fundamental astrophysical models, such as the distance of sources for at least one of the IceCube neutrino excess models. [ABSTRACT FROM AUTHOR]