Advanced Virgo is a major upgrade of the Virgo gravitational-wave detector, aiming to increase its sensitivity by an order of magnitude. Among the main modifications of the instrument, the size of ...the laser beam inside the central area has been roughly doubled. Consequently, the input/output optics systems have been re-designed. Due to the overall Advanced Virgo optical scheme, high-magnification and compact telescopes are needed. These telescopes also have to fulfill stringent requirements in terms of aberrations, separation of secondary beams and scattered light. In this paper we describe the design of the Advanced Virgo telescopes and their estimated performances in terms of tuning capability and optical properties.
We calculate the conductance spectra of a Co atom adsorbed on Cu(111), considering the Co 3d orbitals within a correlated multiple configurations model interacting through the substrate band with the ...Co 4s orbital, which is treated in a mean-field-like approximation. By symmetry, only the dz2 orbital couples with the s orbital through the Cu bands, and the interference between both conduction channels introduces a zero-bias anomaly in the conductance spectra. We find that, while the Kondo resonance is mainly determined by the interaction of the Co d orbitals with the bulk states of the Cu(111) surface, a proper description of the contribution given by the coupling with the localized surface states to the Anderson widths is crucial to describe the interference line shape. We find that the coupling of the Co 4s orbital with the Shockley surface states is responsible for two main features observed in the measured conductance spectra, the dip shape around the Fermi energy and the resonance structure at the surface state low band edge.
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We introduce a novel method aimed to obtain the scale factor between in-plane magnetization components, indispensable for vectorial-magneto-optic Kerr effect (v-MOKE) experiments, convenient for ...experimental setups where it is difficult or unfeasible to rotate the electromagnet. Unlike the original method, in our proposal the electromagnet (and all other optical components) are fixed, extending in this way the possibility to implement v-MOKE magnetometry. Two films, FePt 9 and 100 nm thickness, were used as sample probes, presenting in-plane magnetic uniaxial anisotropy and in-plane magnetic isotropy, respectively. All experiments were carried out at room temperature and employing an home-made MOKE system. We also introduce a closed mathematical expression for the scale factor linking both magnetization components in terms of experimental and sample dependent parameters.
Disintegrins comprise a family of small proteins that bind to and alter the physiological function of integrins, especially integrins that mediate platelet aggregation in blood. Here, we report a ...lysine‐glycine‐aspartic acid (KGD) disintegrin‐like motif present in a 15‐amino acid residue peptide identified in a cDNA library of the amphibian Hypsiboas punctatus skin. The original peptide sequence was used as a template from which five new analogs were designed, chemically synthesized by solid phase, and tested for disintegrin activity and tridimensional structural studies using NMR spectroscopy. The original amphibian peptide had no effect on integrin‐mediated responses. Nevertheless, derived peptide analogs inhibited integrin‐mediated platelet function, including platelet spreading on fibrinogen.
We report a putative disintegrin‐like peptide from an amphibian skin cDNA sequence and designed analogs. Derived peptide analogs inhibited integrin‐mediated platelet function, which also includes platelet spreading on fibrinogen.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Between 2007 and 2010 Virgo collected data in coincidence with the LIGO and GEO gravitational-wave (GW) detectors. These data have been searched for GWs emitted by cataclysmic phenomena in the ...universe, by non-axisymmetric rotating neutron stars or from a stochastic background in the frequency band of the detectors. The sensitivity of GW searches is limited by noise produced by the detector or its environment. It is therefore crucial to characterize the various noise sources in a GW detector. This paper reviews the Virgo detector noise sources, noise propagation, and conversion mechanisms which were identified in the three first Virgo observing runs. In many cases, these investigations allowed us to mitigate noise sources in the detector, or to selectively flag noise events and discard them from the data. We present examples from the joint LIGO-GEO-Virgo GW searches to show how well noise transients and narrow spectral lines have been identified and excluded from the Virgo data. We also discuss how detector characterization can improve the astrophysical reach of GW searches.
Summary
Background Considerable information has been gathered on the functional organization of enteric neuronal circuitries regulating gastrointestinal motility. However, little is known about the ...neuropathophysiological mechanisms underlying gastrointestinal motor disorders.
Aim To analyse the most important pathological findings, clinical implications and therapeutic management of idiopathic enteric neuropathies.
Methods PubMed searches were used to retrieve the literature inherent to molecular determinants, pathophysiological bases and therapeutics of gastrointestinal dysmotility, such as achalasia, gastroparesis, chronic intestinal pseudo‐obstruction, Hirschsprung’s disease and slow transit constipation, to unravel advances on digestive disorders resulting from enteric neuropathies.
Results Current data on molecular and pathological features of enteric neuropathies indicate that degenerative and inflammatory abnormalities can compromise the morpho‐functional integrity of the enteric nervous system. These alterations lead to a massive impairment in gut transit and result in severe abdominal symptoms with associated high morbidity, poor quality of life for patients and established mortality. Many pathophysiological aspects of these severe conditions remain obscure, and therefore treatment options are quite limited and often unsatisfactory.
Conclusions This review of enteric nervous system abnormalities provides a framework to better understand the pathological processes underlying gut dysmotility, to translate this knowledge into clinical management and to foster the development of targeted therapeutic strategies.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
One class of wireless sensor networks makes use of sensor nodes that recharge their batteries by harvesting energy from the surrounding environment. Being continuously recharged, the battery does not ...need to be replaced regularly and the sensor node is maintenance-free. A key module in such sensor network solutions is the data link automatic repeat request (ARQ) protocol, which must be designed to reliably deliver sensor nodes data at the minimum energy cost. With this objective in mind, two ARQ protocol classes are compared. In one class, each sensor node operates individually. In the other, the concept of cooperative communications is adopted, whereby neighboring sensor nodes help each other during the retransmission process. It is shown that the use of cooperative ARQ protocols in energy harvesting sensor networks enables sensor nodes to balance their energy consumption to match their own battery recharge rate. In turn, a balanced energy consumption-to-recharge rate ratio has the potential to improve the network throughput. Both classes of ARQ protocols are analyzed and compared. Estimated throughput gains are discussed under various network scenarios.
We present the results of a search for long-duration gravitational wave transients in the data of the LIGO Hanford and LIGO Livingston second generation detectors between September 2015 and January ...2016, with a total observational time of 49 d. The search targets gravitational wave transients of 10-500 s duration in a frequency band of 24-2048 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. No significant events were observed. As a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. We also show that the search is sensitive to sources in the Galaxy emitting at least 10−8 M⊙c2 in gravitational waves.
In the present work, we propose an ionic Hamiltonian for describing the interaction of graphene with an adsorbed Co atom. In this approach, the electronic correlation effects, related to the many d ...orbitals involved in the interaction, are taken into account by selecting appropriate electronic configurations of the adsorbed atom. The Hamiltonian parameters are calculated considering the localized and extended features of the atom-surface interacting system. The physical quantities of interest are calculated by using a Green functions formalism, solved by means of the equations of motion method closed up to a second order in the atom-band coupling term. The charge and spin fluctuations in the adsorbed Co atom are inferred from density functional theory calculations and assuming that the lower energy configurations obey Hund's rules. The calculated spectral densities and the occurrence probabilities of the different atomic configurations are analyzed as a function of the Co energy level positions and the surface temperature. In addition, the conductance spectra are calculated by using the Keldysh formalism and compared with existing measurements. We analyze the behavior, under variable bias and gate potentials, of resonancelike features in the conductance spectra which can be related to transitions between atomic configurations of low occurrence probability.
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