Modelling the steady state spectral energy distribution of the BL-Lac Object PKS 2155-304 using a selfconsistent SSC model

In this paper we present a fully selfconsistent SSC model with particle acceleration due to shock and stochastic acceleration (Fermi-I and Fermi-II-Processes respectively) to model the quiescent spectral energy distribution (SED) observed from PKS 2155. The simultaneous August/September 2008 multiwavelength data of H.E.S.S., Fermi, RXTE, SWIFT and ATOM give new constraints to the high-energy peak in the SED concerning its curvature. We find that, in our model, a monoenergetic injection of electrons at $\gamma_0 = 910$ into the model region, which are accelerated by Fermi-I- and Fermi-II-processes while suffering synchrotron and inverse Compton losses, finally leads to the observed SED of PKS 2155-30.4 shown in H.E.S.S. and Fermi-LAT collaborations (2009). In contrast to other SSC models our parameters arise from the jet's microphysics and the spectrum is evolving selfconsistently from diffusion and acceleration. The $\gamma_0$-factor can be interpreted as two counterstreaming plasmas due to the motion of the blob at a bulk factor of $\Gamma = 58$ and opposed moving upstream electrons at moderate Lorentz factors with an average of $\gamma_u \approx 8$.Comment: 4 figure

Dynamical quantum phase transitions in systems with continuous symmetry breaking

Interacting many-body systems that are driven far away from equilibrium can exhibit phase transitions between dynamically emerging quantum phases, which manifest as singularities in the Loschmidt echo. Whether and under which conditions such dynamical transitions occur in higher-dimensional systems with spontaneously broken continuous symmetries is largely elusive thus far. Here, we study the dynamics of the Loschmidt echo in the three dimensional O(N) model following a quantum quench from a symmetry breaking initial state. The O(N) model exhibits a dynamical transition in the asymptotic steady state, separating two phases with a finite and vanishing order parameter, that is associated with the broken symmetry. We analytically calculate the rate function of the Loschmidt echo and find that it exhibits periodic kink singularities when this dynamical steady-state transition is crossed. The singularities arise exactly at the zero-crossings of the oscillating order parameter. As a consequence, the appearance of the kink singularities in the transient dynamics is directly linked to a dynamical transition in the order parameter. Furthermore, we argue, that our results for dynamical quantum phase transitions in the O(N) model are general and apply to generic systems with continuous symmetry breaking.Comment: 7 pages, 6 figure

Climate Change Impacts on the Water Resources in the Danube River Basin and Possibilities to Adapt: – The Way to an Adaptation Strategy and its Update

As the Intergovernmental Panel on Climate Change reported in 2013, climate change will have significant impacts on all water sectors. Since water is essential for live, culture, economy and ecosystems, climate change adaptation is crucial. Therefore, a legal and political framework was established by the commissions of the European Union, the United Nations and on national levels. For the Danube River Basin (DRB), the International Commission for the Protection of the Danube River got the mandate to develop an adaptation strategy in 2012 and to update this strategy in 2018. The natural science basis on which the adaptation strategy and its update are based on are two studies, conducted in 2011/2012 and updated and revised in 2017/18. Numerous documents from actual research and development projects and studies dealing with climate change and its impacts on water related issues were analysed in detail and the results summarised. It is agreed that temperature will increase basin-wide. The precipitation trend shows a strong northwest-southeast gradient and significant changes in seasonality. Runoff patterns will change and extreme weather events will intensify. However, the magnitude of the results shows a strong spatial variability due to the heterogeneity of the DRB., It is assessed that these changes will have mostly negative impacts on all water related sectors. Based on the scientific findings an approach for an improved basin-wide strategy on adaptation to climate change is developed. It includes guiding principles and five categories of adaptation measures targeting different objectives

Mitochondria-Targeted Antioxidants SkQ1 and MitoTEMPO Failed to Exert a Long-Term Beneficial Effect in Murine Polymicrobial Sepsis

Mitochondrial-derived reactive oxygen species have been deemed an important contributor in sepsis pathogenesis. We investigated whether two mitochondria-targeted antioxidants (mtAOX; SkQ1 and MitoTEMPO) improved long-term outcome, lessened inflammation, and improved organ homeostasis in polymicrobial murine sepsis. 3-month-old female CD-1 mice (n = 90) underwent cecal ligation and puncture (CLP) and received SkQ1 (5 nmol/kg), MitoTEMPO (50 nmol/kg), or vehicle 5 times post-CLP. Separately, 52 SkQ1-treated CLP mice were sacrificed at 24 h and 48 h for additional endpoints. Neither MitoTEMPO nor SkQ1 exerted any protracted survival benefit. Conversely, SkQ1 exacerbated 28-day mortality by 29%. CLP induced release of 10 circulating cytokines, increased urea, ALT, and LDH, and decreased glucose but irrespectively of treatment. Similar occurred for CLP-induced lymphopenia/neutrophilia and the NO blood release. At 48 h post-CLP, dying mice had approximately 100-fold more CFUs in the spleen than survivors, but this was not SkQ1 related. At 48 h, macrophage and granulocyte counts increased in the peritoneal lavage but irrespectively of SkQ1. Similarly, hepatic mitophagy was not altered by SkQ1 at 24 h. The absence of survival benefit of mtAOX may be due to the extended treatment and/or a relatively moderate-risk-of-death CLP cohort. Long-term effect of mtAOX in abdominal sepsis appears different to sepsis/inflammation models arising from other body compartments

Recently photoassimilated carbon and fungus-delivered nitrogen are spatially correlated in the ectomycorrhizal tissue of Fagus sylvatica

Ectomycorrhizal plants trade plant‐assimilated carbon for soil nutrients with their fungal partners. The underlying mechanisms, however, are not fully understood. Here we investigate the exchange of carbon for nitrogen in the ectomycorrhizal symbiosis of Fagus sylvatica across different spatial scales from the root system to the cellular level. We provided (15)N‐labelled nitrogen to mycorrhizal hyphae associated with one half of the root system of young beech trees, while exposing plants to a (13)CO(2) atmosphere. We analysed the short‐term distribution of (13)C and (15)N in the root system with isotope‐ratio mass spectrometry, and at the cellular scale within a mycorrhizal root tip with nanoscale secondary ion mass spectrometry (NanoSIMS). At the root system scale, plants did not allocate more (13)C to root parts that received more (15)N. Nanoscale secondary ion mass spectrometry imaging, however, revealed a highly heterogenous, and spatially significantly correlated distribution of (13)C and (15)N at the cellular scale. Our results indicate that, on a coarse scale, plants do not allocate a larger proportion of photoassimilated C to root parts associated with N‐delivering ectomycorrhizal fungi. Within the ectomycorrhizal tissue, however, recently plant‐assimilated C and fungus‐delivered N were spatially strongly coupled. Here, NanoSIMS visualisation provides an initial insight into the regulation of ectomycorrhizal C and N exchange at the microscale

Quantitative proteomics identifies reduced NRF2 activity and mitochondrial dysfunction in Atopic Dermatitis

Atopic Dermatitis (AD) is the most common inflammatory skin disease and characterized by a deficient epidermal barrier and cutaneous inflammation. Genetic studies suggest a key role of keratinocytes in AD pathogenesis, but the alterations in the proteome that occur in the full epidermis have not been defined. Using a pressure-cycling technology and data-independent acquisition approach, we performed quantitative proteomics of epidermis from healthy volunteers and lesional and non-lesional patient skin. Results were validated by targeted proteomics using parallel reaction monitoring mass spectrometry and immunofluorescence staining. Proteins that were differentially abundant in the epidermis of AD vs. control patients reflect the strong inflammation in lesional skin and the defect in keratinocyte differentiation and epidermal stratification that already characterizes non-lesional skin. Most importantly, they reveal impaired activation of the NRF2-antioxidant pathway and reduced abundance of mitochondrial proteins involved in key metabolic pathways in the affected epidermis. Analysis of primary human keratinocytes with siRNA-mediated NRF2 knock-down revealed that the impaired NRF2 activation and mitochondrial abnormalities are partially interlinked. These results provide insight into the molecular alterations in the epidermis of AD patients and identify potential targets for pharmaceutical intervention

The Lyman-alpha glow of gas falling into the dark matter halo of a z=3 galaxy

Quasars are the visible signatures of super-massive black holes in the centres of distant galaxies. It has been suggested that quasars are formed during ``major merger events'' when two massive galaxies collide and merge, leading to the prediction that quasars should be found in the centres of the regions of largest overdensity in the early Universe. In dark matter (DM)-dominated models of the early Universe, massive DM halos are predicted to attract the surrounding gas, which falls towards its centre. The neutral gas is not detectable in emission by itself, but gas falling into the ionizing cone of such a quasar will glow in the Lyman-alpha line of hydrogen, effectively imaging the DM halo. Here we present a Lyman-alpha image of a DM halo at redshift 3, along with a two-dimensional spectrum of the gaseous halo. Our observations are best understood in the context of the standard model for DM halos; we infer a mass of (2-7) x 10^12 solar masses (Msun) for the halo.Comment: 4 pages, 4 figures. Published as a Letter to Nature in the August 26, 2004 issue; see accompanying News and Views article by Z. Haiman in the same issu

Lypd6 Enhances Wnt/β-Catenin Signaling by Promoting Lrp6 Phosphorylation in Raft Plasma Membrane Domains

Wnt/beta-catenin signaling plays critical roles during embryogenesis, tissue homeostasis, and regeneration. How Wnt-receptor complex activity is regulated is not yet fully understood. Here, we identify the Ly6 family protein LY6/PLAUR domain-containing 6 (Lypd6) as a positive feedback regulator of Wnt/beta-catenin signaling. lypd6 enhances Wnt signaling in zebrafish and Xenopus embryos and in mammalian cells, and it is required for wnt8-mediated patterning of the mesoderm and neuroectoderm during zebrafish gastrulation. Lypd6 is GPI anchored to the plasma membrane and physically interacts with the Wnt receptor Frizzled8 and the coreceptor Lrp6. Biophysical and biochemical evidence indicates that Lypd6 preferentially localizes to raft membrane domains, where Lrp6 is phosphorylated upon Wnt stimulation. lypd6 knockdown or mislocalization of the Lypd6 protein to nonraft membrane domains shifts Lrp6 phosphorylation to these domains and inhibits Wnt signaling. Thus, Lypd6 appears to control Lrp6 activation specifically in membrane rafts, which is essential for downstream signaling.The GenBank accession number for the partial Xenopus laevis lypd6 complementary DNA reported in this paper is KF042353

Mitochondria-Targeted Antioxidants SkQ1 and MitoTEMPO Failed to Exert a Long-Term Beneficial Effect in Murine Polymicrobial Sepsis

Mitochondrial-derived reactive oxygen species have been deemed an important contributor in sepsis pathogenesis. We investigated whether two mitochondria-targeted antioxidants (mtAOX; SkQ1 and MitoTEMPO) improved long-term outcome, lessened inflammation, and improved organ homeostasis in polymicrobial murine sepsis. 3-month-old female CD-1 mice (n=90) underwent cecal ligation and puncture (CLP) and received SkQ1 (5 nmol/kg), MitoTEMPO (50 nmol/kg), or vehicle 5 times post-CLP. Separately, 52 SkQ1-treated CLP mice were sacrificed at 24 h and 48 h for additional endpoints. Neither MitoTEMPO nor SkQ1 exerted any protracted survival benefit. Conversely, SkQ1 exacerbated 28-day mortality by 29%. CLP induced release of 10 circulating cytokines, increased urea, ALT, and LDH, and decreased glucose but irrespectively of treatment. Similar occurred for CLP-induced lymphopenia/neutrophilia and the NO blood release. At 48 h post-CLP, dying mice had approximately 100-fold more CFUs in the spleen than survivors, but this was not SkQ1 related. At 48 h, macrophage and granulocyte counts increased in the peritoneal lavage but irrespectively of SkQ1. Similarly, hepatic mitophagy was not altered by SkQ1 at 24 h. The absence of survival benefit of mtAOX may be due to the extended treatment and/or a relatively moderate-risk-of-death CLP cohort. Long-term effect of mtAOX in abdominal sepsis appears different to sepsis/inflammation models arising from other body compartments