On 6 April (01:32 UTC) 2009 a MW 6.1 normal faulting earthquake struck the axial area of the Abruzzo region in central Italy. We study the geometry of fault segments using high resolution foreshock ...and aftershock locations. Two main SW dipping segments, the L'Aquila and Campotosto faults, forming an en echelon system 40 km long (NW trending). The 16 km long L'Aquila fault shows a planar geometry with constant dip (∼48°) through the entire upper crust down to 10 km depth. The Campotosto fault activated by three events with 5.0 ≤ MW ≤ 5.2 shows a striking listric geometry, composed by planar segments with different dips along depth rather than a smoothly curving single fault surface. The investigation of the spatiotemporal evolution of foreshock activity within the crustal volume where the subsequent L'Aquila main shock nucleated allows us to image the progressive activation of the main fault plane. From the beginning of 2009 the foreshocks activated the deepest portion of the fault until a week before the main shock, when the largest foreshock (MW 4.0) triggered a minor antithetic segment. Seismicity jumped back to the main plane a few hours before the main shock. Secondary synthetic and antithetic fault segments are present both on the hanging and footwall of the system. The stress tensor obtained by inverting focal mechanisms of the largest events reveals a NE trending extension and the majority of the aftershocks are kinematically consistent. Deviations from the dominant extensional strain pattern are observed for those earthquakes activating minor structures.
Key Points
Anatomy of a complex normal fault system
Imaging a listric normal fault geometry using earthqauke locations
Fault reactivation and tectonic inversion
ABSTRACT The Catania Astrophysical Observatory Spectropolarimeter (CAOS) is a white-pupil cross-dispersed échelle spectrograph with a spectral resolution of up to R = 55,000 in the 375-1100 nm range ...in a single exposure, with complete coverage up to 856 nm. CAOS is linked to the 36-inch telescope, at Mount Etna Observatory, with a couple of 100 m optical fibers and it achieves a signal-to-noise ratio better than 60 for a V = 10 mag star in one hour. CAOS is thermally stabilized in temperature within a 0.01 K rms, so that radial velocities are measured with a precision better than 100 m s−1 from a single spectral line. Linear and circular spectropolarimetric observations are possible by means of a Savart plate working in series with a half-wave and a quarter-wave retarder plate in the 376-850 nm range. As is usual for high-resolution spectropolarimeters, CAOS is suitable to measure all Stokes parameters across spectral lines and it cannot measure the absolute degree of polarization. Observations of unpolarized standard stars show that instrumental polarization is generally zero at 550 nm and can increase up to 3% at the other wavelengths. Since polarized and unpolarized standard stars are useless, we suggest a method to calibrate a high-resolution spectropolarimeter on the basis of the polarimetric properties of spectral lines formed in the presence of a magnetic field. As applied to CAOS, observations of magnetic chemically peculiar stars of the main sequence show that the cross-talk from linear to circular polarization is smaller than 0.4% and that conversion from circular to linear is less than 2.7%. Strength and wavelength dependences of cross-talk can be entirely ascribed, via numerical simulations, to the incorrect retardance of achromatic wave plates.
Despite significant affinity to carbonyl oxygens, thermal hydrogen atoms attach to unmodified polypeptides at a very low rate, while the hydrogen–hydrogen exchange rate is high. Here, using the novel ...omnitrap setup, we found that attachment to polypeptides is much more facile when radical site is already present, but the rate decreases for larger radical ions. The likely explanation is the intramolecular hydrogen atom rearrangement in hydrogen-deficient radicals to a more stable or less accessible site.
The ability to form biofilms contributes significantly to the pathogenesis of many microbial infections, including a variety of ocular diseases often associated with the biofilm formation on foreign ...materials. Carvacrol (Car.) is an important component of essential oils and recently has attracted much attention pursuant to its ability to promote microbial biofilm disruption. In the present study Car. has been encapsulated in poly(dl-lactide-co-glycolide (PLGA) nanocapsules in order to obtain a suitable drug delivery system that could represent a starting point for developing new therapeutic strategies against biofilm-associated infections, such as improving the drug effect by associating an antimicrobial agent with a biofilm viscoelasticity modifier.
Background
Patients with joint hypermobility syndrome/Ehlers–Danlos syndrome, hypermobility type (JHS/EDS‐HT) commonly suffer from pain. How this hereditary connective tissue disorder causes pain ...remains unclear although previous studies suggested it shares similar mechanisms with neuropathic pain and fibromyalgia.
Methods
In this prospective study seeking information on the mechanisms underlying pain in patients with JHS/EDS‐HT, we enrolled 27 consecutive patients with this connective tissue disorder. Patients underwent a detailed clinical examination, including the neuropathic pain questionnaire DN4 and the fibromyalgia rapid screening tool. As quantitative sensory testing methods, we included thermal‐pain perceptive thresholds and the wind‐up ratio and recorded a standard nerve conduction study to assess non‐nociceptive fibres and laser‐evoked potentials, assessing nociceptive fibres.
Results
Clinical examination and diagnostic tests disclosed no somatosensory nervous system damage. Conversely, most patients suffered from widespread pain, the fibromyalgia rapid screening tool elicited positive findings, and quantitative sensory testing showed lowered cold and heat pain thresholds and an increased wind‐up ratio.
Conclusions
While the lack of somatosensory nervous system damage is incompatible with neuropathic pain as the mechanism underlying pain in JHS/EDS‐HT, the lowered cold and heat pain thresholds and increased wind‐up ratio imply that pain in JHS/EDS‐HT might arise through central sensitization. Hence, this connective tissue disorder and fibromyalgia share similar pain mechanisms.
What does this study add?
In patients with JHS/EDS‐HT, the persistent nociceptive input due to joint abnormalities probably triggers central sensitization in the dorsal horn neurons and causes widespread pain.
Source Code Repositories * Github (http://github.com): A web-based hosting service for software development projects that use the Git revision control system, including many open-source projects. * ...Git (http://git-scm.com): A free and open-source distributed version control system designed to handle everything from small to very large projects with speed and efficiency. * Mercurial (http://mercurial.selenic.com): A free, distributed source control management tool. Systems to Package, Access, and Execute Data and Code * IPython Notebook (http://ipython.org/notebook.html): A web-based interactive computational environment where you can combine code execution, text, mathematics, plots, and rich media into a single document. * ROpenSci (http://ropensci.org): A suite of packages that allow access to data repositories through the R statistical programming environment. * Authorea (https://authorea.com): A collaborative online word processor for scholarly papers that allows the writing of web-native, living, dynamic, "executable" articles that include text, mathematical notation, images, and data.
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