Abstract
We report on long-term multiwavelength monitoring of blazar Mrk 421 by the GLAST-AGILE Support Program of the Whole Earth Blazar Telescope (GASP-WEBT) collaboration and Steward Observatory, ...and by the Swift and Fermi satellites. We study the source behaviour in the period 2007–2015, characterized by several extreme flares. The ratio between the optical, X-ray and γ-ray fluxes is very variable. The γ-ray flux variations show a fair correlation with the optical ones starting from 2012. We analyse spectropolarimetric data and find wavelength-dependence of the polarization degree (P), which is compatible with the presence of the host galaxy, and no wavelength dependence of the electric vector polarization angle (EVPA). Optical polarimetry shows a lack of simple correlation between P and flux and wide rotations of the EVPA. We build broad-band spectral energy distributions with simultaneous near-infrared and optical data from the GASP-WEBT and ultraviolet and X-ray data from the Swift satellite. They show strong variability in both flux and X-ray spectral shape and suggest a shift of the synchrotron peak up to a factor of ∼50 in frequency. The interpretation of the flux and spectral variability is compatible with jet models including at least two emitting regions that can change their orientation with respect to the line of sight.
Abstract
In 2015 July 29–September 1, the satellite XMM–Newton pointed at the BL Lac object PG 1553+133 six times, collecting data for 218 h. During one of these epochs, simultaneous observations by ...the Swift satellite were requested to compare the results of the X-ray and optical–UV instruments. Optical, near-infrared and radio monitoring was carried out by the Whole Earth Blazar Telescope (WEBT) collaboration for the whole observing season. We here present the results of the analysis of all these data, together with an investigation of the source photometric and polarimetric behaviour over the last 3 yr. The 2015 EPIC spectra show slight curvature and the corresponding light curves display fast X-ray variability with a time-scale of the order of 1 h. In contrast to previous results, during the brightest X-ray states detected in 2015 the simple log-parabolic model that best fits the XMM–Newton data also reproduces reasonably well the whole synchrotron bump, suggesting a peak in the near-UV band. We found evidence of a wide rotation of the polarization angle in 2014, when the polarization degree was variable, but the flux remained almost constant. This is difficult to interpret with deterministic jet emission models, while it can be easily reproduced by assuming some turbulence of the magnetic field.
Progress in neurodegenerative disease research is hampered by the lack of biomarkers of neuronal dysfunction. We here identified a class of cerebrospinal fluid-based (CSF-based) kinetic biomarkers ...that reflect altered neuronal transport of protein cargo, a common feature of neurodegeneration. After a pulse administration of heavy water (2H2O), distinct, newly synthesized 2H-labeled neuronal proteins were transported to nerve terminals and secreted, and then appeared in CSF. In 3 mouse models of neurodegeneration, distinct 2H-cargo proteins displayed delayed appearance and disappearance kinetics in the CSF, suggestive of aberrant transport kinetics. Microtubule-modulating pharmacotherapy normalized CSF-based kinetics of affected 2H-cargo proteins and ameliorated neurodegenerative symptoms in mice. After 2H2O labeling, similar neuronal transport deficits were observed in CSF of patients with Parkinson's disease (PD) compared with non-PD control subjects, which indicates that these biomarkers are translatable and relevant to human disease. Measurement of transport kinetics may provide a sensitive method to monitor progression of neurodegeneration and treatment effects.
Progress in neurodegenerative disease research is hampered by the lack of biomarkers of neuronal dysfunction. We here identified a class of cerebrospinal fluid-based (CSF-based) kinetic biomarkers ...that reflect altered neuronal transport of protein cargo, a common feature of neurodegeneration. After a pulse administration of heavy water (.sup.2H.sub.2O), distinct, newly synthesized .sup.2H-labeled neuronal proteins were transported to nerve terminals and secreted, and then appeared in CSF. In 3 mouse models of neurodegeneration, distinct .sup.2H-cargo proteins displayed delayed appearance and disappearance kinetics in the CSF, suggestive of aberrant transport kinetics. Microtubule-modulating pharmacotherapy normalized CSF-based kinetics of affected .sup.2H-cargo proteins and ameliorated neurodegenerative symptoms in mice. After .sup.2H.sub.2O labeling, similar neuronal transport deficits were observed in CSF of patients with Parkinson's disease (PD) compared with non-PD control subjects, which indicates that these biomarkers are translatable and relevant to human disease. Measurement of transport kinetics may provide a sensitive method to monitor progression of neurodegeneration and treatment effects.
We report on long-term multiwavelength monitoring of blazar Mrk 421 by the GLAST-AGILE Support Program of the Whole Earth Blazar Telescope (GASP-WEBT) collaboration and Steward Observatory, and by ...the Swift and Fermi satellites. We study the source behaviour in the period 2007-2015, characterized by several extreme flares. The ratio between the optical, X-ray and gamma-ray fluxes is very variable. The gamma-ray flux variations show a fair correlation with the optical ones starting from 2012. We analyse spectropolarimetric data and find wavelength-dependence of the polarization degree (P), which is compatible with the presence of the host galaxy, and no wavelength dependence of the electric vector polarization angle (EVPA). Optical polarimetry shows a lack of simple correlation between P and flux and wide rotations of the EVPA. We build broad-band spectral energy distributions with simultaneous near-infrared and optical data from the GASP-WEBT and ultraviolet and X-ray data from the Swift satellite. They show strong variability in both flux and X-ray spectral shape and suggest a shift of the synchrotron peak up to a factor of similar to 50 in frequency. The interpretation of the flux and spectral variability is compatible with jet models including at least two emitting regions that can change their orientation with respect to the line of sight.
We present a multiwavelength study of the flat-spectrum radio quasar CTA 102 during 2013-2017. We use radio-to-optical data obtained by the Whole Earth Blazar Telescope, 15 GHz data from the Owens ...Valley Radio Observatory, 91 and 103 GHz data from the Atacama Large Millimeter Array, near-infrared data from the Rapid Eye Monitor telescope, as well as data from the Swift (optical-UV and X-rays) and Fermi (\(\gamma\) rays) satellites to study flux and spectral variability and the correlation between flux changes at different wavelengths. Unprecedented \(\gamma\)-ray flaring activity was observed during 2016 November-2017 February, with four major outbursts. A peak flux of (2158 \(\pm\) 63)\(\times\)10\(^{-8}\) ph cm\(^{-2}\) s\(^{-1}\), corresponding to a luminosity of (2.2 \(\pm\) 0.1)\(\times\)10\(^{50}\) erg s\(^{-1}\), was reached on 2016 December 28. These four \(\gamma\)-ray outbursts have corresponding events in the near-infrared, optical, and UV bands, with the peaks observed at the same time. A general agreement between X-ray and \(\gamma\)-ray activity is found. The \(\gamma\)-ray flux variations show a general, strong correlation with the optical ones with no time lag between the two bands and a comparable variability amplitude. This \(\gamma\)-ray/optical relationship is in agreement with the geometrical model that has successfully explained the low-energy flux and spectral behaviour, suggesting that the long-term flux variations are mainly due to changes in the Doppler factor produced by variations of the viewing angle of the emitting regions. The difference in behaviour between radio and higher energy emission would be ascribed to different viewing angles of the jet regions producing their emission.
Built-in self-test (BIST) techniques are rapidly becoming an industry-wide standard test technique in the design of testing support hardware for VLSI circuits. In the BIST setup both test pattern ...generation and output response analysis are performed on-chip hardware. In this manuscript a BIST scheme based on immune system is presented. The main conceptual ingredient utilized in order to build the proposed scheme is the application of the negative-selection mechanism of the immune system, which is able to discriminate between the self (body's own cell) and any foreign cell (non-self). Experimental results concerning fault detection in some ISCAS85 benchmarks circuits are presented
ims.The very high energy (VHE&100GeV)γ-ray MAGIC observations of the blazar S4 0954+65, were triggered by anexceptionally high flux state of emission in the optical. This blazar has a disputed ...redshift ofz= 0.368 orz>0.45 and an uncertainclassification among blazar subclasses. The exceptional source state described here makes for an excellent opportunity to understandphysical processes in the jet of S4 0954+65 and thus contribute to its classification.Methods.We investigated the multiwavelength (MWL) light curve and spectral energy distribution (SED) of the S4 0954+65 blazarduring an enhanced state in February 2015 and have put it in context with possible emission scenarios. We collected photometric datain radio, optical, X-ray, andγ-ray. We studied both the optical polarization and the inner parsec-scale jet behavior with 43 GHz data.Results.Observations with the MAGIC telescopes led to the first detection of S4 0954+65 at VHE. Simultaneous data withFermi-LAT at high energyγ-ray(HE, 100 MeV
The genomic region that lies between the telomere and chromosome body, termed the subtelomere, is heterochromatic, repeat-rich, and frequently undergoes rearrangement. Within this region, large-scale ...structural changes enable gene diversification, and, as such, large multicopy gene families are often found at the subtelomere. In some parasites, genes associated with proliferation, invasion, and survival are often found in these regions, where they benefit from the subtelomere's highly plastic, rapidly changing nature. The increasing availability of complete (or near complete) parasite genomes provides an opportunity to investigate these typically poorly defined and overlooked genomic regions and potentially reveal relevant gene families necessary for the parasite's lifestyle.
Using the latest chromosome-scale genome assembly and hallmark repeat richness observed at chromosome termini, we have identified and characterised the subtelomeres of Schistosoma mansoni, a metazoan parasitic flatworm that infects over 250 million people worldwide. Approximately 12% of the S. mansoni genome is classified as subtelomeric, and, in line with other organisms, we find these regions to be gene-poor but rich in transposable elements. We find that S. mansoni subtelomeres have undergone extensive interchromosomal recombination and that these sites disproportionately contribute to the 2.3% of the genome derived from segmental duplications. This recombination has led to the expansion of subtelomeric gene clusters containing 103 genes, including the immunomodulatory annexins and other gene families with unknown roles. The largest of these is a 49-copy plexin domain-containing protein cluster, exclusively expressed in the tegument-the tissue located at the host-parasite physical interface-of intramolluscan life stages.
We propose that subtelomeric regions act as a genomic playground for trial-and-error of gene duplication and subsequent divergence. Owing to the importance of subtelomeric genes in other parasites, gene families implicated in this subtelomeric expansion within S. mansoni warrant further characterisation for a potential role in parasitism.
Context. PKS 1510−089 is one of only a few flat spectrum radio quasars detected in the very-high-energy (VHE, > 100 GeV) gamma-ray band. Aims. We study the broadband spectral and temporal properties ...of the PKS 1510−089 emission during a high gamma-ray state. Methods. We performed VHE gamma-ray observations of PKS 1510−089 with the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes during a long, high gamma-ray state in May 2015. In order to perform broadband modeling of the source, we have also gathered contemporaneous multiwavelength data in radio, IR, optical photometry and polarization, UV, X-ray, and GeV gamma-ray ranges. We construct a broadband spectral energy distribution (SED) in two periods, selected according to VHE gamma-ray state. Results. PKS 1510−089 was detected by MAGIC during a few day-long observations performed in the middle of a long, high optical and gamma-ray state, showing for the first time a significant VHE gamma-ray variability. Similarly to the optical and gamma-ray high state of the source detected in 2012, it was accompanied by a rotation of the optical polarization angle and the emission of a new jet component observed in radio. However, owing to large uncertainty on the knot separation time, the association with the VHE gamma-ray emission cannot be firmly established. The spectral shape in the VHE band during the flare is similar to those obtained during previous measurements of the source. The observed flux variability sets constraints for the first time on the size of the region from which VHE gamma rays are emitted. We model the broadband SED in the framework of the external Compton scenario and discuss the possible emission site in view of multiwavelength data and alternative emission models. Key words: galaxies: active / galaxies: jets / gamma rays: galaxies / quasars: individual: PKS 1510-089
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