725 research outputs found

    “Western Mediterranean” (WM) broad band network: permanent seismic monitoring at the Ibero-Maghrebian region

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    The “Ibero-Maghrebian” region, a western part of the Eurasia-Africa plate boundary, is a broad deformation area without a well defined plate boundary line, comprising the Southern part of the Iberian Peninsula, the Northwestern part of Africa, the Gulf of Cadiz and the Alboran Sea, with a convergence between Iberia and Africa at some mm/year (Nuvel-1A model, DeMets et al, 1994) in a NNW-SSE direction, and a dif- ferential motion at Alboran Sea area (Buforn et al, 1995). Although seismic activity is characterized by a low to moderate magnitude and shallow depth earthquakes, big events are also well documented, among others: Lisbon earthquake (1755, I0= X), Gulf of Cadiz (1969, Ms= 8.1), or, more recently Bourmedes (2003, Mw= 7.1), some them with an associated tsunami, like Lisbon or Bourmedes earthquakes. An interme- diate seismic activity is also clearly registered from Gulf of Cadiz to mid Alboran Sea (Martin Davila and Pazos, 2003), and very deep earthquakes (h> 650 km) have been registered at Granada basin (1954, M= 7.0). In order to better study the seismic characteristics of this area, from 1996 on, ROA and the University Complutense of Madrid (UCM), with the collaboration of Geo- forschungZentrum of Potsdam (GFZ), have deployed a broad band seismic net with stations located at Southern Spain and Spanish possessions located Northern Africa, mainly surrounding the Alboran Sea, complementing the previously installed ROA SP and LP stations. This net has been named as “Western Mediterranean net” (WM FDSN code). As net was evolving, new Institutes and stations joined WM net, such a way at present is formed by ten stations located at: San Fernando (SFS), Málaga (MALA), Cartagena (CART), and Evora (UEVO, University of Evora, Portugal) at Iberian peninsula, Mahón (MAHO) at Minorca island, three stations at Melilla (MELI), Peñón de Vélez-Gomera (PVLZ), and Ceuta (CEU) at Spanish villages located Northern Africa in South Alboran Sea area, and Averroes (AVE) and Ifrane (IFR) installed at Morocco mainland as a joined effort among ISRABAT (Institut Scientifique, Univer- sité Mohammed V), ROA and UCM. Most stations are collocated with permanent geodetic GPS stations (Gárate et al, 2004). Next future plans include the installation of five stations by U. Evora at Southern Portugal area, a new station at Morocco by ISRABAT, ROA and UCM and also a new station at Oran (Algeria), as a collaboration among Université d’Oran (Algeria), ROA and UCM. All them will be associated to WM net. All WM network stations include Streckeisen STS-2 sensor, a Quanterra or Earth Data digitizer, and a SeiscomP process system (Heinloo, 2004), and all them are available in real time via phone modem or Internet, except PVLZ and CEU, which will be in short. In this work, partly funded by the Spanish Ministry of Education and Science (MEC) through the project REN2006-10311-C03-01/02 (RISTE), we will present the present status, the next future plans and some related activities of WM net

    Improving noise assessment at intersections by modeling traffic dynamics

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    Three families of road noise prediction models can be distinguished. Static noise models only consider free-flow constant-speed traffic with uniformly distributed vehicles. Analytic noise models assume that all vehicles are isolated from one another but account for their mean kinematic profile over the network. Micro-simulation noise models relax the hypothesis of no interaction between vehicles and fully capture traffic flow dynamic effects such as queue evolution. This study compares the noise levels obtained by these three methodologies at signalized intersections and roundabouts. It reveals that micro-simulation noise models outperform the other approaches. Particularly, they are able to capture the effects of stochastic transient queues in under-saturated conditions as well as stop-and-go behaviors in oversaturated regime. Accounting for traffic dynamics is also shown to improve predictions of noise variations due to different junction layouts. In this paper, a roundabout is found to induce a 2.5 dB(A) noise reduction compared to a signalized intersection in undersaturated conditions while the acoustic contributions of both kinds of junctions balance in oversaturated regime. (C) 2008 Elsevier Ltd. All rights reserved

    PENGARUH RASIO EPOKSI/AMPAS TEBU DAN PERLAKUAN ALKALI PADA AMPAS TEBU TERHADAP KEKUATAN BENTUR KOMPOSIT PARTIKEL EPOKSI BERPENGISI SERAT AMPAS TEBU

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    This study was aimed to determine the effect of alkali treatment and fiber composition on the impact strength properties of epoxy composites filled with bagasse fiber. Composites are made by hand lay-up method by mixing epoxy and bagasse fiber with variation of volume ratio between matrix and filler are 100/0, 70/30, 60/40, and 50/50 (v / v) and the concentration of NaOH slolution in the alkali treatment are 0% , 1%, 2%, and 3%. Mechanical propertie tested was impact strengthand analized  by SEM analysis. The results obtained from this study was the maximum impact strength value obtained of the composite was on the composition 70:30 with 2% NaOH concentration was 8,005 kJ/m2

    Neural sensing and control in a kilometer-scale gravitational-wave observatory

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    Suspended optics in gravitational-wave (GW) observatories are susceptible to alignment perturbations, particularly slow drifts over time, due to variations in temperature and seismic levels. Such misalignments affect the coupling of the incident laser beam into the optical cavities, degrade both the circulating power and optomechanical photon squeezing, and thus decrease the astrophysical sensitivity to merging binaries. Traditional alignment techniques involve differential wave-front sensing using multiple quadrant photodiodes but are often bandwidth restricted and limited by the sensing noise. We present a successful implementation of neural-network-based sensing and control at a GW observatory and demonstrate low-frequency control of the signal-recycling mirror at the GEO 600 detector. Alignment information for three critical optics is simultaneously extracted from the interferometric dark-port camera images via a convolutional neural net-long short-term memory network architecture and is then used for multiple-input-multiple-output control using soft actor-critic-based deep reinforcement learning. The overall sensitivity improvement achieved using our scheme demonstrates the capabilities of deep learning as a viable tool for real-time sensing and control for current and next-generation GW interferometers

    First demonstration of neural sensing and control in a kilometer-scale gravitational wave observatory

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    Suspended optics in gravitational wave (GW) observatories are susceptible toalignment perturbations and, in particular, to slow drifts over time due tovariations in temperature and seismic levels. Such misalignments affect thecoupling of the incident laser beam into the optical cavities, degrade bothcirculating power and optomechanical photon squeezing, and thus decrease theastrophysical sensitivity to merging binaries. Traditional alignment techniquesinvolve differential wavefront sensing using multiple quadrant photodiodes, butare often restricted in bandwidth and are limited by the sensing noise. Wepresent the first-ever successful implementation of neural network-basedsensing and control at a gravitational wave observatory and demonstratelow-frequency control of the signal recycling mirror at the GEO 600 detector.Alignment information for three critical optics is simultaneously extractedfrom the interferometric dark port camera images via a CNN-LSTM networkarchitecture and is then used for MIMO control using soft actor-critic-baseddeep reinforcement learning. Overall sensitivity improvement achieved using ourscheme demonstrates deep learning's capabilities as a viable tool for real-timesensing and control for current and next-generation GW interferometers.<br

    Characterization of the major histocompatibility complex locus association with Behçet’s disease in Iran

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    © 2015 Xavier et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Introduction: The aim of this study was to characterize the association of human leukocyte antigen (HLA) B alleles and major histocompatibility complex (MHC) single nucleotide polymorphisms (SNPs) with Behçet's disease (BD) in an Iranian dataset. Methods: The association of three SNPs in the MHC region previously identified as the most associated in high-density genotyping studies was tested in a case-control study on 973 BD patients and 825 controls from Iran, and the association of HLA-B alleles was tested in a subset of 681 patients and 414 controls. Results: We found that HLA-B*51 (P = 4.11 × 10(-41), OR [95% CI] = 4.63[3.66-5.85]) and B*15 confer risk for BD (P = 2.83 × 10(-2), OR [95% CI] = 1.75[1.08-2.84]) in Iranian, and in B*51 negative individuals, only the B*15 allele is significantly associated with BD (P = 2.51 × 10(-3), OR [95% CI] = 2.40[1.37-4.20]). rs76546355, formerly known as rs116799036, located between HLA-B and MICA (MHC class I polypeptide-related sequence A), demonstrated the same level of association with BD as HLA-B*51 (P adj = 1.78 × 10(-46), OR [95% CI] = 5.46[4.21-7.09], and P adj = 8.34 × 10(-48), OR [95% CI] = 5.44[4.20-7.05], respectively) in the HLA-B allelotyped subset, while rs2848713 was less associated (P adj = 7.14 × 10(-35), OR [95% CI] = 3.73[2.97-4.69]) and rs9260997 was not associated (P adj = 1.00 × 10(-1)). Additionally, we found that B*51 genotype-phenotype correlations do not survive Bonferroni correction, while carriers of the rs76546355 risk allele predominate in BD cases with genital ulcers, positive pathergy test and positive BD family history (2.31 × 10(-4) ≀ P ≀ 1.59 × 10(-3)). Conclusions: We found that the HLA-B*51 allele and the rs76546355/rs116799036 MHC SNP are independent genetic risk factors for BD in Iranian, and that positivity for the rs76546355/rs116799036 risk allele, but not for B*51, does correlate with specific demographic characteristics or clinical manifestations in BD patients.This work was supported by the Portuguese Fundação para a CiĂȘncia e a Tecnologia (grants PTDC/SAU-GMG/098937/2008, PTDC/IIM-GES/5015/2012 and CMUP-ERI/TPE/0028/2013, fellowships SFRH/BD/43895/2008 to JMX, SFRH/BPD/35737/2007 to PA, SFRH/BPD/70008/2010 to IS, a CiĂȘncia and an Investigator-FCT contract to SAO), and the Research Committee of the Tehran University of Medical Sciences (grant 132/714).info:eu-repo/semantics/publishedVersio

    Gene Expression Profiling and Association Studies Implicate the Neuregulin Signaling Pathway in Behçet's Disease Susceptibility

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    Behçet's disease (BD) is a complex disease with genetic and environmental risk factors implicated in its etiology; however, its pathophysiology is poorly understood. To decipher BD's genetic underpinnings, we combined gene expression profiling with pathway analysis and association studies. We compared the gene expression profiles in peripheral blood mononuclear cells (PBMCs) of 15 patients and 14 matched controls using Affymetrix microarrays and found that the neuregulin signaling pathway was over-represented among the differentially expressed genes. The Epiregulin (EREG), Amphiregulin (AREG), and Neuregulin-1 (NRG1) genes of this pathway stand out as they are also among the top differentially expressed genes. Twelve haplotype tagging SNPs at the EREG-AREG locus and 15 SNPs in NRG1 found associated in at least one published BD genome-wide association study were tested for association with BD in a dataset of 976 Iranian patients and 839 controls. We found a novel association with BD for the rs6845297 SNP located downstream of EREG, and replicated three associations at NRG1 (rs4489285, rs383632, and rs1462891). Multifactor dimensionality reduction analysis indicated the existence of epistatic interactions between EREG and NRG1 variants. EREG-AREG and NRG1, which are members of the epidermal growth factor (EGF) family, seem to modulate BD susceptibility through main effects and gene–gene interactions. These association findings support a role for the EGF/ErbB signaling pathway inBD pathogenesis that warrants further investigation and highlight the importance of combining genetic and genomic approaches to dissect the genetic architecture of complex diseases

    Status of the SOLEIL femtosecond X-ray source

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    http://accelconf.web.cern.ch/AccelConf/FEL2012/papers/wepd04.pdfInternational audienceAn electron bunch slicing setup is presently under construction on the SOLEIL storage ring for delivering 100 fs (rms) long photon pulses to two undulator-based beamlines providing soft (TEMPO) and hard X-rays (CRISTAL). Thanks to the non-zero dispersion function present in all straight sections of the storage ring, the sliced bunches can be easily separated from the core bunches. The modulator is a wiggler composed of 20 periods of 164.4 mm. It produces a magnetic field of 1.8 T at a minimum gap of 14.5 mm. To modulate the kinetic energy of the electrons in the wiggler, a Ti:Sa laser will be used, which produces 50 fs pulses at 800 nm with a repetition rate of 2.5 kHz. The laser beam is splitted into two branches in order to provide 2 mJ to the modulator and 0.5 mJ as pump pulse for the CRISTAL and TEMPO end stations. Focusing optics and beam path, from the laser hutch to the inside of the storage ring tunnel are presently under finalization. In this paper, we will report on the specificities of the SOLEIL setup, the status of its installation and the expected performances
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