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The growth of the toxic Genera Microcoleus on different bottom substrates was presented. The sampling was performed in the Virgin River of Zion's National Park. 

Cyanobacterium Microcoleus anatoxicus, isolated from a coastal stream in northern California, produces both anatoxin-a (ATX) and dihydroanatoxin- a (dhATX), responsible for dog deaths, but its environmental preferences are unknown. We tested the effect of environmentally relevant stressors, e.g., salinity enrichment and nitrogen (N) depletion, on mat formation and toxicity of M. anatoxicus during the stationary growth phase in culture. Microcoleus anatoxicus showed broad salinity tolerance and the potential to enter estuaries and produce toxins in mesohaline conditions. Maximum growth was observed in oligohaline waters with salinity of 4.6 ppt. Moderate salinity stress (up to 7.8 ppt) did not affect dhATX production significantly. In contrast, higher salinity above 9.3 ppt had a detrimental effect on cell growth and significantly suppressed dhATX production. Formation of a common polysaccharide sheath covering multiple filaments was characteristic with increased salinity and may provide protection against osmotic stress. Microcoleus anatoxicus grown for 40 days in N-depleted medium formed mats with significantly elevated dhATX and increased ATX concentrations. Phycobilisome degradation was a possible acclimation response to N-limitation, as indicated by distinctly keritomized and pale cells in these cultures. In both experiments, most of the anatoxins were extracellular,probably due to toxin leaking during the stationary growth phase. 

This paper presents the first integration of PropBank role information into Wikidata, in order to provide a novel resource for information extraction, one combining Wikidata`s ontological metadata with PropBank`s rich argument structure encoding for event classes. We discuss a technique for PropBank augmentation to existing eventive Wikidata items, as well as identification of gaps in Wikidata`s coverage based on manual examination of over 11,300 PropBank rolesets. We propose five new Wikidata properties to integrate PropBank structure into Wikidata so that the annotated mappings can be added en masse. We then outline the methodology and challenges of this integration, including annotation with the combined resources. 

Abstract We perform nuclear magnetic resonance (NMR) measurements of the oxygen-17 Knight shifts for Sr₂RuO₄, while subjected to uniaxial stress applied along [100] direction. The resulting strain is associated with a strong variation of the temperature and magnetic field dependence of the inferred magnetic response. A quasiparticle description based on density-functional theory calculations, supplemented by many-body renormalizations, is found to reproduce our experimental results, and highlights the key role of a van-Hove singularity. The Fermi-liquid coherence scale is shown to be tunable by strain, and driven to low values as the associated Lifshitz transition is approached. 

The presence of relativistic electrons within the diffuse gas phase of galaxy clusters is now well established, thanks to deep radio observations obtained over the last decade, but their detailed origin remains unclear. Cosmic ray protons are also expected to accumulate during the formation of clusters. They may explain part of the radio signal and would lead to γ -ray emission through hadronic interactions within the thermal gas. Recently, the detection of γ -ray emission has been reported toward the Coma cluster with Fermi -LAT. Assuming that this γ -ray emission arises essentially from pion decay produced in proton-proton collisions within the intracluster medium (ICM), we aim at exploring the implication of this signal on the cosmic ray content of the Coma cluster and comparing it to observations at other wavelengths. We use the MINOT software to build a physical model of the Coma cluster, which includes the thermal target gas, the magnetic field strength, and the cosmic rays, to compute the corresponding expected γ -ray signal. We apply this model to the Fermi -LAT data using a binned likelihood approach, together with constraints from X-ray and Sunyaev-Zel’dovich observations. We also consider contamination from compact sources and the impact of various systematic effects on the results. We confirm that a significant γ -ray signal is observed within the characteristic radius θ 500 of the Coma cluster, with a test statistic TS ≃ 27 for our baseline model. The presence of a possible point source (4FGL J1256.9+2736) may account for most of the observed signal. However, this source could also correspond to the peak of the diffuse emission of the cluster itself as it is strongly degenerate with the expected ICM emission, and extended models match the data better. Given the Fermi -LAT angular resolution and the faintness of the signal, it is not possible to strongly constrain the shape of the cosmic ray proton spatial distribution when assuming an ICM origin of the signal, but preference is found in a relatively flat distribution elongated toward the southwest, which, based on data at other wavelengths, matches the spatial distribution of the other cluster components well. Assuming that the whole γ -ray signal is associated with hadronic interactions in the ICM, we constrain the cosmic ray to thermal energy ratio within R 500 to X CRp = 1.79 −0.30 +1.11 % and the slope of the energy spectrum of cosmic rays to α = 2.80 −0.13 +0.67 ( X CRp = 1.06 −0.22 +0.96 % and α = 2.58 −0.09 +1.12 when including both the cluster and 4FGL J1256.9+2736 in our model). Finally, we compute the synchrotron emission associated with the secondary electrons produced in hadronic interactions assuming steady state. This emission is about four times lower than the overall observed radio signal (six times lower when including 4FGL J1256.9+2736), so that primary cosmic ray electrons or reacceleration of secondary electrons is necessary to explain the total emission. We constrain the amplitude of the primary to secondary electrons, or the required boost from reacceleration with respect to the steady state hadronic case, depending on the scenario, as a function of radius. Our results confirm that γ -ray emission is detected in the direction of the Coma cluster. Assuming that the emission is due to hadronic interactions in the intracluster gas, they provide the first quantitative measurement of the cosmic ray proton content in a galaxy cluster and its implication for the cosmic ray electron populations. 

Physical computing toolkits for children expose young minds to the concepts of computing and electronics within a target activity. To this end, these kits usually make use of a custom Visual Programming Language (or VPL) environment that extends past the functionality of simply programming, often also incorporating representations of electronics aspects in the interface. These representations of the electronics function as a scaffold to help the child focus on programming, instead of having to handle both the programming and details of the electronics at the same time. This paper presents a review of existing physical computing toolkits, looking at the What, How, and Where of electronics representations in their VPL interfaces. We then discuss potential research directions for the design of VPL interfaces for physical computing toolkits for children.