21 research outputs found
Tailoring nanostructured surfaces with plasmonic/magnetic multifunctional response
IIn this work, we present an innovative way to functionalize large surfaces combining both plasmonic and magnetic nanoparticles on a substrate, by the growth of bilayers and a subsequent single annealing. In particular, we show here the formation of Au and gamma- Fe₂O₃ nanoparticles using this route. Thermal treatments promote the nanostructuration of the film plus a partial oxidation of Fe to form ferrimagnetic oxides. For this purpose, annealing conditions and the structure of the bilayer must be selected to achieve an optimal nanostructuration, avoiding the full oxidation of Fe to form antiferromagnetic hematite. Published by AIP Publishing
Elliptic flow of charged particles in Pb-Pb collisions at 2.76 TeV
We report the first measurement of charged particle elliptic flow in Pb-Pb
collisions at 2.76 TeV with the ALICE detector at the CERN Large Hadron
Collider. The measurement is performed in the central pseudorapidity region
(||<0.8) and transverse momentum range 0.2< < 5.0 GeV/. The
elliptic flow signal v, measured using the 4-particle correlation method,
averaged over transverse momentum and pseudorapidity is 0.087 0.002
(stat) 0.004 (syst) in the 40-50% centrality class. The differential
elliptic flow v reaches a maximum of 0.2 near = 3
GeV/. Compared to RHIC Au-Au collisions at 200 GeV, the elliptic flow
increases by about 30%. Some hydrodynamic model predictions which include
viscous corrections are in agreement with the observed increase.Comment: 10 pages, 4 captioned figures, published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/389
A precise measurement of the Z -boson double-differential transverse momentum and rapidity distributions in the full phase space of the decay leptons with the ATLAS experiment at √s = 8 TeV
This paper presents for the first time a precise measurement of the production properties of the Z boson in the full phase space of the decay leptons. This is in contrast to the many previous precise unfolded measurements performed in the fiducial phase space of the decay leptons. The measurement is obtained from proton–proton collision data collected by the ATLAS experiment in 2012 at s=8 TeV at the LHC and corresponding to an integrated luminosity of 20.2 fb-1. The results, based on a total of 15.3 million Z-boson decays to electron and muon pairs, extend and improve a previous measurement of the full set of angular coefficients describing Z-boson decay. The double-differential cross-section distributions in Z-boson transverse momentum pT and rapidity y are measured in the pole region, defined as 80<mℓℓ<100 GeV, over the range |y|<3.6. The total uncertainty of the normalised cross-section measurements in the peak region of the pT distribution is dominated by statistical uncertainties over the full range and increases as a function of rapidity from 0.5–1.0% for |y|<2.0 to 2-7% at higher rapidities. The results for the rapidity-dependent transverse momentum distributions are compared to state-of-the-art QCD predictions, which combine in the best cases approximate N4LL resummation with N3LO fixed-order perturbative calculations. The differential rapidity distributions integrated over pT are even more precise, with accuracies from 0.2–0.3% for |y|<2.0 to 0.4–0.9% at higher rapidities, and are compared to fixed-order QCD predictions using the most recent parton distribution functions. The agreement between data and predictions is quite good in most cases
The heterogeneous flexible periodic vehicle routing problem: Mathematical formulations and solution algorithms
The aim of this paper is to introduce the Flexible Periodic Vehicle Routing Problem with Heterogeneous Fleet, a variant of the Periodic Vehicle Routing Problem. Flexibility is introduced in service schedules and delivered quantities, heterogeneity comes from different vehicles capacities and speeds. Three Mixed-Integer Linear Programming formulations and a matheuristic, based on Kernel Search, are proposed. Computational tests are made to evaluate the performance of the three formulations and to assess the quality of the solutions provided by the matheuristic
Microscopic and NanoSIMS characterization of black shale-hosted pre-kinematic pyrites: Possible gold source of the orogenic gold deposits in the Truchas Syncline (Variscan Iberian Massif)
The Truchas Syncline contains orogenic gold deposits (OGDs), hosted mainly by the Armorican Quartzite Fm. In order to look for the source of gold in these deposits, pre-kinematic sulphides from black shales from the overlying Luarca Fm. were studied using both optical and scanning electron (SEM) microscopy, as well as nanoscale secondary ion mass spectrometry (NanoSIMS). NanoSIMS images allowed the observation of relevant structures (pyrite with high As content nodules) hidden to SEM.
Microscopy and 36S, 75As32S, 75As, 75As34S, and 197Au mappings, as well as δ34S analysis (‰ Vienna-Canyon Diablo Troilite) allowed 4 types of pyrite to be characterized. According to their sequence of deposition, the pyrite types identified are the following: (1) framboid nuclei (FmPy), with δ34S between +4.1‰ and +57.5‰; (2) overgrowths (OgPy), with presence of Au, As and δ34S of approximately +20.5‰; (3) pyrite with high As content (AsPy), replacing previous pyrites, with δ34S of approximately +23‰, nodular shapes and non-detected Au; (4) subhedral pyrite (ShPy), with δ34S of approximately +19.7‰ and Au and As distribution showing (a) nuclei, (b) rims with Au and As and (c) structures interpreted as replacements of previous pyrite. Luarca Fm. pyrite framboids reach 75 µm in size, larger than framboids described in most previous NanoSIMS work, with microcrystals sufficiently large to be analyzed without contamination from edge effects. The FmPy formed in early diagenetic conditions by dissimilatory reduction of marine sulphate plus Rayleigh distillation or anaerobic oxidation of methane processes. The first FmPy nuclei formed in the periphery of framboids, and then started to form in the central region until completion of the framboidal structure. Growth of OgPy, AsPy and ShPy corresponded to more advanced diagenetic conditions, although the last stage of ShPy growth followed an aggregation model, in which ShPy metamorphic pyrites grew over ShPy diagenetic pyrites.
The sulphur isotopic signature of the four types of pyrite is in good agreement with a source from Ordovician marine sulphate. A hypothesis stating that the source of Au in OGDs in the district could be in Luarca Fm. is supported by the results of the present research. Firstly, a source of Au in the district could have been the replacement of previous pyrites by AsPy and the release of Au to the system, instead of the framboidal to euhedral pyrite recrystallization process observed in other gold deposits. Secondly, by the correspondence between δ34S isotopic signature of the pyrites from Luarca Fm. and those from sulphides in OGDs. However, these results do not rule out other possible sources
-scattering on heavy unstable proton-rich nuclei in inverse kinematics at energies around the Coulomb barrier for the astrophysical p-process
Fibromyalgia's Key Symptoms in Normal-Weight, Overweight, and Obese Female Patients
Factors affecting the symptomatology of fibromyalgia (FM) are not fully understood. The aim of the present study was to analyze the relationship of weight status with pain, fatigue, and stiffness in Spanish female FM patients, with special focus on the differences between overweight and obese patients. The sample comprised 177 Spanish women with FM (51.3 ± 7.3 years old). We assessed tenderness (using pressure algometry), pain and vitality using the General Health Short-Form Survey (SF36), and pain, fatigue, morning tiredness, and stiffness using the Fibromyalgia Impact Questionnaire (FIQ). The international criteria for body mass index was used to classify the patients as normal weight, overweight, or obese. Thirtytwo percent were normal-weight, 35% overweight, and 32% obese. Both overweight and obese patients had higher levels of pain than normalweight patients, as assessed by FIQ and SF36 questionnaires and tender point count (p < .01). The same pattern was observed for algometer score, yet the differences were not significant. Both overweight and obese patients had higher levels of fatigue, and morning tiredness, and stiffness (p < .05) and less vitality than normal-weight patients. No significant differences were observed in any of the variables studied between overweight and obese patients. In conclusion, FM symptomatology in obese patients did not differ from overweight patients, whereas normal-weight patients significantly differed from overweight and obese patients in the studied symptoms. These findings suggest that keeping a healthy (normal) weight is not only associated with decreased risk for developing FM but might also be a relevant and useful way of improving FM symptomatology in women. Ó 2011 by the American Society for Pain Management Nursing Fibromyalgia (FM) is a disorder characterized by the concurrent existence of chronic widespread musculoskeletal pain and multiple sites of tendernes