117 research outputs found
RTLola Cleared for Take-Off: Monitoring Autonomous Aircraft
The autonomous control of unmanned aircraft is a highly safety-critical
domain with great economic potential in a wide range of application areas,
including logistics, agriculture, civil engineering, and disaster recovery. We
report on the development of a dynamic monitoring framework for the DLR ARTIS
(Autonomous Rotorcraft Testbed for Intelligent Systems) family of unmanned
aircraft based on the formal specification language RTLola. RTLola is a
stream-based specification language for real-time properties. An RTLola
specification of hazardous situations and system failures is statically
analyzed in terms of consistency and resource usage and then automatically
translated into an FPGA-based monitor. Our approach leads to highly efficient,
parallelized monitors with formal guarantees on the noninterference of the
monitor with the normal operation of the autonomous system
The astrocyte-produced growth factor HB-EGF limits autoimmune CNS pathology
Central nervous system (CNS)-resident cells such as microglia, oligodendrocytes and astrocytes are gaining increasing attention in respect to their contribution to CNS pathologies including multiple sclerosis (MS). Several studies have demonstrated the involvement of pro-inflammatory glial subsets in the pathogenesis and propagation of inflammatory events in MS and its animal models. However, it has only recently become clear that the underlying heterogeneity of astrocytes and microglia can not only drive inflammation, but also lead to its resolution through direct and indirect mechanisms. Failure of these tissue-protective mechanisms may potentiate disease and increase the risk of conversion to progressive stages of MS, for which currently available therapies are limited. Using proteomic analyses of cerebrospinal fluid specimens from patients with MS in combination with experimental studies, we here identify Heparin-binding EGF-like growth factor (HB-EGF) as a central mediator of tissue-protective and anti-inflammatory effects important for the recovery from acute inflammatory lesions in CNS autoimmunity. Hypoxic conditions drive the rapid upregulation of HB-EGF by astrocytes during early CNS inflammation, while pro-inflammatory conditions suppress trophic HB-EGF signaling through epigenetic modifications. Finally, we demonstrate both anti-inflammatory and tissue-protective effects of HB-EGF in a broad variety of cell types in vitro and use intranasal administration of HB-EGF in acute and post-acute stages of autoimmune neuroinflammation to attenuate disease in a preclinical mouse model of MS. Altogether, we identify astrocyte-derived HB-EGF and its epigenetic regulation as a modulator of autoimmune CNS inflammation and potential therapeutic target in MS. Linnerbauer and colleagues find that HB-EGF produced by reactive astrocytes is protective during autoimmune neuroinflammation, but epigenetically suppressed during late stages
CASTAway : An asteroid main belt tour and survey
CASTAway is a mission concept to explore our Solar System's main asteroid belt. Asteroids and comets provide a window into the formation and evolution of our Solar System and the composition of these objects can be inferred from space-based remote sensing using spectroscopic techniques. Variations in composition across the asteroid populations provide a tracer for the dynamical evolution of the Solar System. The mission combines a long-range (point source) telescopic survey of over 10,000 objects, targeted close encounters with 10-20 asteroids and serendipitous searches to constrain the distribution of smaller (e.g. 10 m) size objects into a single concept. With a carefully targeted trajectory that loops through the asteroid belt, CASTAway would provide a comprehensive survey of the main belt at multiple scales. The scientific payload comprises a 50 cm diameter telescope that includes an integrated low-resolution (R = 30-100) spectrometer and visible context imager, a thermal (e.g. 6-16 mu m) imager for use during the flybys, and modified star tracker cameras to detect small (similar to 10 m) asteroids. The CASTAway spacecraft and payload have high levels of technology readiness and are designed to fit within the programmatic and cost caps for a European Space Agency medium class mission, while delivering a significant increase in knowledge of our Solar System. (C) 2017 COSPAR. Published by Elsevier Ltd. All rights reserved.Peer reviewe
Distinctive Gut Microbiota of Honey Bees Assessed Using Deep Sampling from Individual Worker Bees
Surveys of 16S rDNA sequences from the honey bee, Apis mellifera, have revealed the presence of eight distinctive bacterial phylotypes in intestinal tracts of adult worker bees. Because previous studies have been limited to relatively few sequences from samples pooled from multiple hosts, the extent of variation in this microbiota among individuals within and between colonies and locations has been unclear. We surveyed the gut microbiota of 40 individual workers from two sites, Arizona and Maryland USA, sampling four colonies per site. Universal primers were used to amplify regions of 16S ribosomal RNA genes, and amplicons were sequenced using 454 pyrotag methods, enabling analysis of about 330,000 bacterial reads. Over 99% of these sequences belonged to clusters for which the first blastn hits in GenBank were members of the known bee phylotypes. Four phylotypes, one within Gammaproteobacteria (corresponding to “Candidatus Gilliamella apicola”) one within Betaproteobacteria (“Candidatus Snodgrassella alvi”), and two within Lactobacillus, were present in every bee, though their frequencies varied. The same typical bacterial phylotypes were present in all colonies and at both sites. Community profiles differed significantly among colonies and between sites, mostly due to the presence in some Arizona colonies of two species of Enterobacteriaceae not retrieved previously from bees. Analysis of Sanger sequences of rRNA of the Snodgrassella and Gilliamella phylotypes revealed that single bees contain numerous distinct strains of each phylotype. Strains showed some differentiation between localities, especially for the Snodgrassella phylotype
Radar Observations and the Shape of Near-Earth Asteroid 2008 EV5
We observed the near-Earth asteroid 2008 EV5 with the Arecibo and Goldstone
planetary radars and the Very Long Baseline Array during December 2008. EV5
rotates retrograde and its overall shape is a 400 /pm 50 m oblate spheroid. The
most prominent surface feature is a ridge parallel to the asteroid's equator
that is broken by a concavity 150 m in diameter. Otherwise the asteroid's
surface is notably smooth on decameter scales. EV5's radar and optical albedos
are consistent with either rocky or stony-iron composition. The equatorial
ridge is similar to structure seen on the rubble-pile near-Earth asteroid
(66391) 1999 KW4 and is consistent with YORP spin-up reconfiguring the asteroid
in the past. We interpret the concavity as an impact crater. Shaking during the
impact and later regolith redistribution may have erased smaller features,
explaining the general lack of decameter-scale surface structure.Comment: This paper has been accepted for publication in Icarus:
http://www.sciencedirect.com/science/article/B6WGF-5207B2F-4/2/d87cd2ae4da00c2b277e2dc79a532c4
CMS physics technical design report : Addendum on high density QCD with heavy ions
Peer reviewe
Peptidic soil components are a major dietary resource for the humivorous larvae of Pachnoda spp. (Coleoptera: Scarabaeidae)
Peptidic soil components are a major dietary resource for the humivorous larvae of Pachnoda spp. (Coleoptera : Scarabaeidae)
Inter- and intraspecific comparison of the bacterial assemblages in the hindgut of humivorous scarab beetle larvae (Pachnoda spp.)
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