1,425 research outputs found

    CONGRuENTS (COsmic-ray, Neutrino, Gamma-ray and Radio Non-Thermal Spectra). I. A predictive model for galactic non-thermal emission

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    The total luminosity and spectral shape of the non-thermal emission produced by cosmic rays depends on their interstellar environment, a dependence that gives rise to correlations between galaxies' bulk properties -- star formation rate, stellar mass, and others -- and their non-thermal spectra. Understanding the physical mechanisms of cosmic ray transport, loss, and emission is key to understanding these correlations. Here, in the first paper of the series, we present a new method to compute the non-thermal spectra of star-forming galaxies, and describe an open-source software package -- COsmic-ray, Neutrino, Gamma-ray and Radio Non-Thermal Spectra (CONGRuENTS) -- that implements it. As a crucial innovation, our method requires as input only a galaxy's effective radius, star formation rate, stellar mass, and redshift, all quantities that are readily available for large samples of galaxies and do not require expensive, spatially resolved gas measurements. From these inputs we derive individual, galaxy-by-galaxy models for the background gas and radiation field through which cosmic rays propagate, from which we compute steady state cosmic ray spectra for hadronic and leptonic particles in both the galactic disc and halo by solving the full kinetic equation. We invoke modern models for cosmic ray transport and include all significant emission and loss mechanisms. In this paper we describe the model and validate it against non-thermal emission measured in nearby star-forming galaxies that span four orders of magnitude in star formation rate.Comment: 23 pages, 14 figures, 1 table, accepted for publication in MNRA

    Typesetting Forms with I4mX

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    Abstract The Air Force Forms System (AFFORMS) is combination of a user-friendly fill-in-the-blank front end and a LAW-based forms typesetting system. The overall system is described and the procedure to develop a LAW style for a form is presented

    State anxiety and cortisol reactivity to skydiving in novice versus experienced skydivers

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    Previous studies have suggested that skydiving, a naturalistic stressor, is associated with increases in self-reported stress, anxiety and cortisol levels. However, it has not been established whether this stress reactivity is altered as a function of repeated exposure to skydiving. This is of interest due to previous observations that cortisol reactivity becomes habituated with repeated exposure to laboratory stressors, however, few studies have investigated such habituation to naturalistic stressors. State anxiety and cortisol reactivity to skydiving were measured in 11 first-time skydivers and 13 experienced skydivers (≄ 30 jumps, mean jumps = 397.6), who were to complete a solo skydive. The novice skydivers reported significantly greater levels of state anxiety prior to the jump; however, there were no differences in pre-jump levels of salivary cortisol. Both groups exhibited significantly elevated salivary cortisol levels immediately post-jump, relative to i) pre-jump and ii) recovery. However, the two groups were indistinguishable with regard to their cortisol reactivity to the skydive. These findings support previous research demonstrating that skydiving elicits acute cortisol activation. Further, they suggest that i) cortisol reactivity does not habituate in experienced jumpers, and ii) that there is lack of concordance between self-reported levels of anxiety and biological stress reactivity in experienced skydivers

    Ab Initio No Core Shell Model - Recent Results and Further Prospects

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    There has been significant recent progress in solving the long-standing problems of how nuclear shell structure and collective motion emerge from underlying microscopic inter-nucleon interactions. We review a selection of recent significant results within the ab initio No Core Shell Model (NCSM) closely tied to three major factors enabling this progress: (1) improved nuclear interactions that accurately describe the experimental two-nucleon and three-nucleon interaction data; (2) advances in algorithms to simulate the quantum many-body problem with strong interactions; and (3) continued rapid development of high-performance computers now capable of performing 20×101520 \times 10^{15} floating point operations per second. We also comment on prospects for further developments.Comment: Invited paper presented at NTSE-2014 and published online in the proceedings (see footnote on p.1

    Drug regulatory-compliant validation of a qPCR assay for bioanalysis studies of a cell therapy product with a special focus on matrix interferences in a wide range of organ tissues

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    Quantitative polymerase chain reaction (qPCR) has emerged as an important bioanalytical method for assessing the pharmacokinetics of human-cell-based medicinal products after xenotransplantation into immunodeficient mice. A particular challenge in bioanalytical qPCR studies is that the different tissues of the host organism can affect amplification efficiency and amplicon detection to varying degrees, and ignoring these matrix effects can easily cause a significant underestimation of the true number of target cells in a sample. Here, we describe the development and drug regulatory-compliant validation of a TaqMan qPCR assay for the quantification of mesenchymal stromal cells in the range of 125 to 20,000 cells/200 L lysate via the amplification of a human-specific, highly repetitive α-satellite DNA sequence of the chromosome 17 centromere region HSSATA17. An assessment of matrix effects in 14 different mouse tissues and blood revealed a wide range of spike recovery rates across the different tissue types, from 11 to 174%. Based on these observations, we propose performing systematic spike-and-recovery experiments during assay validation and correcting for the effects of the different tissue matrices on cell quantification in subsequent bioanalytical studies by multiplying the back-calculated cell number by tissue-specific factors derived from the inverse of the validated percent recovery rate

    Swiss medical centres vary significantly when it comes to outcomes of neonates with a very low gestational age.

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    AIM: This study quantified the impact of perinatal predictors and medical centre on the outcome of very low-gestational-age neonates (VLGANs) born at <32 completed weeks in Switzerland. METHODS: Using prospectively collected data from a 10-year cohort of VLGANs, we developed logistic regression models for three different time points: delivery, NICU admission and seven days of age. The data predicted survival to discharge without severe neonatal morbidity, such as major brain injury, moderate or severe bronchopulmonary dysplasia, retinopathy of prematurity (≄stage three) or necrotising enterocolitis (≄stage three). RESULTS: From 2002 to 2011, 6892 VLGANs were identified: 5854 (85%) of the live-born infants survived and 84% of the survivors did not have severe neonatal complications. Predictors for adverse outcome at delivery and on NICU admission were low gestational age, low birthweight, male sex, multiple birth, birth defects and lack of antenatal corticosteroids. Proven sepsis was an additional risk factor on day seven of life. The medical centre remained a statistically significant factor at all three time points after adjusting for perinatal predictors. CONCLUSION: After adjusting for perinatal factors, the survival of Swiss VLGANs without severe neonatal morbidity was strongly influenced by the medical centre that treated them

    Nonlinear optical properties of meso-Tetra(fluorenyl)porphyrins peripherally functionalized with one to four ruthenium alkynyl substituents

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    The synthesis of a series of four porphyrin derivatives based on a meso-tetrafluorenylporphyrin core functionalized with one to four trans-chlorobis(dppe)ruthenium alkynyl units (dppe = 1,2-bis(diphenylphosphino)ethane) at the periphery, together with cyclic voltammetry (CV) and UV–Vis absorption and emission spectroscopy studies, are reported. In these multipolar assemblies, the organoruthenium endgroups are potential electron-donors and the central porphyrin core is a potential electron-acceptor. The third-order nonlinear optical (NLO) responses have been assessed by Z-scan, revealing that these extended π-networks incorporating polarizable organometallic units behave as nonlinear absorbers in the near-IR range. The role of the peripheral transition metal centers on the third-order NLO properties is discussed

    Kinetics of wound development and healing suggests a skin-stabilizing effect of allogeneic ABCB5+ mesenchymal stromal cell treatment in recessive dystrophic epidermolysis bullosa

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    Recessive dystrophic epidermolysis (RDEB) is a rare, inherited, and currently incurable skin blistering disorder characterized by cyclically recurring wounds coexisting with chronic non-healing wounds. In a recent clinical trial, three intravenous infusions of skin-derived ABCB5+ mesenchymal stromal cells (MSCs) to 14 patients with RDEB improved the healing of wounds that were present at baseline. Since in RDEB even minor mechanical forces perpetually provoke the development of new or recurrent wounds, a post-hoc analysis of patient photographs was performed to specifically assess the effects of ABCB5+ MSCs on new or recurrent wounds by evaluating 174 wounds that occurred after baseline. During 12 weeks of systemic treatment with ABCB5+ MSCs, the number of newly occurring wounds declined. When compared to the previously reported healing responses of the wounds present at baseline, the newly occurring wounds healed faster, and a greater portion of healed wounds remained stably closed. These data suggest a previously undescribed skin-stabilizing effect of treatment with ABCB5+ MSCs and support repeated dosing of ABCB5+ MSCs in RDEB to continuously slow the wound development and accelerate the healing of new or recurrent wounds before they become infected or progress to a chronic, difficult-to-heal stage
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