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Abstract We report the detection of very high energy gamma-ray emission from the blazar S3 1227+25 (VER J1230+253) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). VERITAS observations of the source were triggered by the detection of a hard-spectrum GeV flare on 2015 May 15 with the Fermi-Large Area Telescope (LAT). A combined 5 hr VERITAS exposure on May 16 and 18 resulted in a strong 13σdetection with a differential photon spectral index, Γ = 3.8 ± 0.4, and a flux level at 9% of the Crab Nebula above 120 GeV. This also triggered target-of-opportunity observations with Swift, optical photometry, polarimetry, and radio measurements, also presented in this work, in addition to the VERITAS and Fermi-LAT data. A temporal analysis of the gamma-ray flux during this period finds evidence of a shortest variability timescale ofτ_obs= 6.2 ± 0.9 hr, indicating emission from compact regions within the jet, and the combined gamma-ray spectrum shows no strong evidence of a spectral cutoff. An investigation into correlations between the multiwavelength observations found evidence of optical and gamma-ray correlations, suggesting a single-zone model of emission. Finally, the multiwavelength spectral energy distribution is well described by a simple one-zone leptonic synchrotron self-Compton radiation model. 

This paper describes the scalable fabrication of smart electronic textiles (e-textiles) capable of simultaneous sensing, filtration, and detoxification of sulfur dioxide (SO2). The templated method converts pre-deposited copper metal into copper hydroxide, followed by conversion into a copper-based hexahydroxytriphenylene metal-organic framework (MOF) (Cu3(HHTP)2), to afford a large-area (10 × 10 cm2) conductive coating (sheet resistance = 0.1–0.3 MΩ). The resulting e-textiles achieve sensing (theoretical limit of detection [LOD] of 0.43 ppm), filtration (adsorption uptake of 1.9 and 0.83 mmol g−1 for MOF powder and MOF/textile, respectively, at 1 bar and 298 K), and detoxification (redox conversion of SO2 gas into solid sulfate) due to the selective material-analyte interactions. This scalable method for generating e-textiles is a promising approach for the fabrication of smart membrane materials with multifunctional performance characteristics. 

Two-dimensional (2D) metal oxide semiconductors offer a superlative combination of high electron mobility and visible-range transparency uniquely suitable for flexible transparent electronics. Synthesis of these ultrathin (<3 nm) semiconductors by Cabrera-Mott oxidation of liquid metals could enable emerging device applications but requires the precise design of their electrostatics at the nanoscale. This study demonstrates sub-nanometer-level control over the thickness of semiconducting 2D antimony-doped indium oxide (AIO) by manipulating the kinetics of Cabrera-Mott oxidation through variable-speed liquid metal printing at plastic-compatible temperatures (175°C). By modulating both the growth kinetics and doping, we engineer the conductivity and crystallinity of AIO for integration in ultrathin channel transistors exhibiting exceptional steep turn-on, on-off ratios > 106 and an outstanding average mobility of 34.7 ± 12.9 cm2/Vs. This result shows the potential for kinetically controlling 2D oxide synthesis for various high-performance optoelectronic device applications. 

Self-organization under out-of-equilibrium conditions is ubiquitous in natural systems for the generation of hierarchical solid-state patterns of complex structures with intricate properties. Efforts in applying this strategy to synthetic materials that mimic biological function have resulted in remarkable demonstrations of programmable self-healing and adaptive materials. However, the extension of these efforts to multifunctional stimuli-responsive solidstate materials across defined spatial distributions remains an unrealized technological opportunity. This paper describes the use of a nonequilibrium reaction−diffusion process to achieve the synthesis of a multifunctional stimuli-responsive electrically conductive metal−organic framework (cMOF) in a gelled medium with control over particle size and spatial periodicity on a macroscopic scale. Upon integration into chemiresistive devices, the resulting cMOF particles exhibit a size-dependent response toward hydrogen sulfide gas, as determined by their distinct surface-to-volume ratio, porosity, unique synthesis methodology, and unusual microcrystallite morphology compared to their counterparts obtained through bulk solution phase synthesis. Taken altogether, these achievements pave the way toward gaining access to functional nanomaterials with well-defined chemical composition, dimensions, and precisely tailored functions using far-from-equilibrium approaches. 

Persons with cystic fibrosis (CF), starting in early life, show intestinal microbiome dysbiosis characterized in part by a decreasedrelative abundance of the genus Bacteroides. Bacteroides is a major producer of the intestinal short chain fatty acid propionate. Wdemonstrate here that cystic fibrosis transmembrane conductance regulator-defective (CFTR−/−) Caco-2 intestinal epithelial cellsresponsive to the anti-inflammatory effects of propionate. Furthermore, Bacteroides isolates inhibit the IL-1β-induced inflammatorresponse of CFTR−/− Caco-2 intestinal epithelial cells and do so in a propionate-dependent manner. The introduction of Bacteroisupplemented stool from infants with cystic fibrosis into the gut of CftrF508del mice results in higher propionate in the stool as wethe reduction in several systemic pro-inflammatory cytokines. Bacteroides supplementation also reduced the fecal relativeabundance of Escherichia coli, indicating a potential interaction between these two microbes, consistent with previous clinicalstudies. For a Bacteroides propionate mutant in the mouse model, pro-inflammatory cytokine KC is higher in the airway and serucompared with the wild-type (WT) strain, with no significant difference in the absolute abundance of these two strains. Takentogether, our data indicate the potential multiple roles of Bacteroides-derived propionate in the modulation of systemic and airwayinflammation and mediating the intestinal ecology of infants and children with CF. The roles of Bacteroides and the propionate itproduces may help explain the observed gut-lung axis in CF and could guide the development of probiotics to mitigate systemic aairway inflammation for persons with CF. 

Cystic fibrosis is a heritable disease that disrupts ion transport at mucosal surfaces, causing a buildup of mucus and dysregulation of microbial communities in both the lungs and the intestines. Persons with CF are known to have dysbiotic gut microbial communities, but the development of these communities over time beginning at birth has not been thoroughly studied. Here, we describe an observation study following the development of the gut microbiome of cwCF throughout the first 4 years of life, during the critical window of both gut microbiome and immune development. Our findings indicate the possibility of the gut microbiota as a reservoir of airway pathogens and a surprisingly early indication of a microbiota associated with inflammatory bowel disease.