1,520 research outputs found
Cotilos impactados vs. roscados no cementados: estudio radiológico post-operatorio comparativo
Se han valorado radiografías AP de pelvis obtenidas tras colocación de 102 pró-
tesis no cementadas en 97 pacientes: 51 eran del tipo cótilo roscado (CR), y 51 del tipo cótilo
impactado (CI). Se ha medido el ángulo de inclinación, la posición del cotilo, el grado de centraje,
el grado de protrusión/extrusión, y la superficie de contacto entre cótilo y la cavidad acetabular.
Globahnente los CR quedan implantados más verticalmente que los CI (p=0,006), así como
más lateralizados (p=0,02). El porcentaje de cótilos bien centrados en relación al acetábulo es
mayor entre los CI que entre los CR (p=0,002). Un 19% de los CR quedaron parcialmente extraídos,
no llegando a contactar con el fondo de la cavidad acetabular, mientras que en ningún
caso de los CI se apreció este problema. En conclusión, a pesar de la teórica ventaja de poseer
una estabilidad inicial mayor, la orientación de los CR no resulta tan óptima como la obtenida
con los CI, lo que asegura una estabilidad mejor a largo plazo y una menor usura del polietileno.—Post-operative anteroposterior radiographs of the pelvis in 102 patients receiving
a cementless total hip arthroplasty were analyzed. In a group, a screwed spherical socket
(SCR) was applied, while in other a press-fit impacted socket (IMP) was used. The following parameters
were studied: inclination angle, location and centering of the acetabular component,
degree of protrusion-extrusion, and porcentage of contact surface between the socket and the
acetabulum. SCR sockets appeared to be placed more vertically (p=0.006), and laterally
(p=0.02) than IMP prostheses. The percent of properly centered sockets was higher among
IMP than among SCR implants (p=0.002). SCR prostheses were found to be partly extruded in
19% of cases while none of the IMP prostheses had this problem. In conclussion, despite the
theoretical advantage of the SCR implants having a better initial fixation than the IMP implants,
the latter tend to be implanted in a more optimal position, thus ensuring a better longterm
stability and therefore less wear problems can be expected
Real space observation of the magnetic coupling between a Co film and a barium hexaferrite film
RIVA ONLINE 2021 – IBERIAN VACUUM ONLINE MEETING.
The Iberian Vacuum Conference, (Reunión Ibérica de Vacío, RIVA) is a joint meeting of the Portuguese Vacuum Society (SOPORVAC) and the Spanish Vacuum Society (ASEVA),
2021 RIVA will take place ON-LINE from 4-6th October 2021. .-https://aseva.es/conferences/riva-online/Barium ferrite (BaFe12O19, BFO) is a hexagonal ferrite with applications as permanent magnet in many different devices due to its high magnetocrystalline anisotropy, high coercive field and low cost. However, the moderate saturation magnetization of BFO
means that the energy product is orders of magnitude smaller than the one that rare-earth-based magnetic materials offer. To overcome this limitation, a commonly proposed strategy to enhance the energy product is exchange-coupling the magnetically hard
component (BFO) with a soft phase in order to improve the combined remanent magnetization without a high loss in coercivity. Nonetheless, the results obtained in other hard/soft systems (SFO/Co bilayers) have pointed out the difficulty to take advantage of
this rigid coupling magnetic regime1. In this research, we focus on two steps to investigate the Co/BFO coupling in a bilayer system: first, we sought to obtain BFO films with an in-
plane magnetic easy axis to avoid shape anisotropy competition, and second, we deposit Co on top of such a BFO film while monitoring both the BFO and Co magnetic domains
A Platform for Addressing Individual Magnetite Islands Grown Epitaxially on Ru(0001) and Manipulating Their Magnetic Domains
We have grown high-quality magnetite micrometric islands on ruthenium stripes
on sapphire through a combination of magnetron sputtering (Ru film),
high-temperature molecular beam epitaxy (oxide islands), and optical
lithography. The samples have been characterized by atomic force microscopy,
Raman spectroscopy, X-ray absorption and magnetic circular dichroism in a
photoemission microscope. The magnetic domains on the magnetite islands can be
modified by the application of current pulses through the Ru stripes in
combination with magnetic fields. The modification of the magnetic domains is
explained by the Oersted field generated by the electrical current flowing
through the stripes underneath the magnetite nanostructures. The fabrication
method is applicable to a wide variety of rock salt and spinel oxides
FeCo Nanowire-Strontium Ferrite Powder Composites for Permanent Magnets with High-Energy Products
Due to the issues associated with rare-earth elements, there arises a strong
need for magnets with properties between those of ferrites and rare-earth
magnets that could substitute the latter in selected applications. Here, we
produce a high remanent magnetization composite bonded magnet by mixing FeCo
nanowire powders with hexaferrite particles. In the first step, metallic
nanowires with diameters between 30 and 100 nm and length of at least 2 {\mu}m
are fabricated by electrodeposition. The oriented as-synthesized nanowires show
remanence ratios above 0.76 and coercivities above 199 kA/m and resist core
oxidation up to 300 {\deg}C due to the existence of a > 8 nm thin oxide
passivating shell. In the second step, a composite powder is fabricated by
mixing the nanowires with hexaferrite particles. After the optimal nanowire
diameter and composite composition are selected, a bonded magnet is produced.
The resulting magnet presents a 20% increase in remanence and an enhancement of
the energy product of 48% with respect to a pure hexaferrite (strontium
ferrite) magnet. These results put nanowire-ferrite composites at the forefront
as candidate materials for alternative magnets for substitution of rare earths
in applications that operate with moderate magnet performance
The Mass-Metallicity relation explored with CALIFA: I. Is there a dependence on the star formation rate?
We present the results on the study of the global and local M-Z relation
based on the first data available from the CALIFA survey (150 galaxies). This
survey provides integral field spectroscopy of the complete optical extent of
each galaxy (up to 2-3 effective radii), with enough resolution to separate
individual HII regions and/or aggregations. Nearly 3000 individual HII
regions have been detected. The spectra cover the wavelength range between
[OII]3727 and [SII]6731, with a sufficient signal-to-noise to derive the oxygen
abundance and star-formation rate associated with each region. In addition, we
have computed the integrated and spatially resolved stellar masses (and surface
densities), based on SDSS photometric data. We explore the relations between
the stellar mass, oxygen abundance and star-formation rate using this dataset.
We derive a tight relation between the integrated stellar mass and the
gas-phase abundance, with a dispersion smaller than the one already reported in
the literature (0.07 dex). Indeed, this
dispersion is only slightly larger than the typical error derived for our
oxygen abundances. However, we do not find any secondary relation with the
star-formation rate, other than the one induced due to the primary relation of
this quantity with the stellar mass. We confirm the result using the 3000
individual HII regions, for the corresponding local relations.
Our results agree with the scenario in which gas recycling in galaxies, both
locally and globally, is much faster than other typical timescales, like that
of gas accretion by inflow and/or metal loss due to outflows. In essence,
late-type/disk dominated galaxies seem to be in a quasi-steady situation, with
a behavior similar to the one expected from an instantaneous
recycling/closed-box model.Comment: 19 Pages, 8 figures, Accepted for Publishing in Astronomy and
Astrophysics (A&A
The International Linear Collider: Report to Snow mass 2021
DESY-22-045,IFT–UAM/CSIC–22-028, KEKPreprint2021-61,PNNL-SA-160884, SLAC-PUB-17662.ILC International Development Team and ILC community: et al.The International Linear Collider (ILC) is on the table now as a new global energy-frontier accelerator laboratory taking data in the 2030s. The ILC addresses key questions for our current understanding of particle physics. It is based on a proven accelerator technology. Its experiments will challenge the Standard Model of particle physics and will provide a new window to look beyond it. This document brings the story of the ILC up to date, emphasizing its strong physics motivation, its readiness for construction, and the opportunity it presents to the US and the global particle physics community.The work of the DESY group is supported by the Deutsche Forschungsgemeinschaft under Germany's Excellence Strategy, EXC 2121 \Quantum Universe", grant 390833306. The work of IFIC is supported by Projects No. PGC2018-094856-B-100 (MCIN/AEI), PROMETEO-2018/060 and CIDEGENT/2020/21 (Generalitat Valenciana) and iLINK Grant No. LINKB20065 (CSIC). The work of the KEK group is supported in part by JSPS KAKENHI Grant Numbers 16H02173 and 21H01077. The work of the SLAC group is supported by the US Department of Energy, contract DE{AC02{76SF00515. The work of James Brau is supported by the US Department of Energy grant DE-SC0017996. The work of Francesco Giovanni Celiberto is supported by the INFN/NINPHA project. The work of Sven Heinemeyer is supported in part by the grant PID2019-110058GB-C21
funded by MCIN/AEI/10.13039/501100011033 and by "ERDF A way of making Europe", and in part by the grant CEX2020-001007-S funded by MCIN/AEI/10.13039/501100011033. The work of Sunghoon Jung is supported by the National Research Foundation of Korea under grant NRF-2017R1D1A1B03030820. The work of Zhen Liu is supported in part by the U.S. Department of Energy (DOE) under grant No. DE-SC0022345. The work of Nathaniel Craig is supported in part by the U.S. Department of Energy under the grant DE-SC0011702. The work of Alessandro Papa is supported by the INFN/QFTCOLLIDERS project.The work of Junping Tian is supported in part by the Japan Society for the Promotion of Science under the Grant-in-Aid for Science Research 15H02083. The work of Graham Wilson is supported by the US National Science Foundation under
award NSF 2013007.N
The problematic use of Information and Communication Technologies (ICT) in adolescents by the cross sectional JOITIC study
Background: The emerging field of Information and Communications Technology (ICT) has brought about new interaction styles. Its excessive use may lead to addictive behaviours. The objective is to determine the prevalence of the problematic use of ICT such as Internet, mobile phones and video games, among adolescents enrolled in mandatory Secondary Education (ESO in Spanish) and to examine associated factors. Methods: Cross sectional, multi-centric descriptive study. Population: 5538 students enrolled in years one to four of ESO at 28 schools in the Vallès Occidental region (Barcelona, Spain). Data collection: self-administered socio-demographic and ICT access questionnaire, and validated questionnaires on experiences related to the use of the Internet, mobile phones and video games (CERI, CERM, CERV). Results: Questionnaires were collected from 5,538 adolescents between the ages of 12 and 20 (77.3 % of the total response), 48.6 % were females. Problematic use of the Internet was observed in 13.6 % of the surveyed individuals; problematic use of mobile phones in 2.4 % and problematic use in video games in 6.2 %. Problematic Internet use was associated with female students, tobacco consumption, a background of binge drinking, the use of cannabis or other drugs, poor academic performance, poor family relationships and an intensive use of the computer. Factors associated with the problematic use of mobile phones were the consumption of other drugs and an intensive use of these devices. Frequent problems with video game use have been associated with male students, the consumption of other drugs, poor academic performance, poor family relationships and an intensive use of these games. Conclusions: This study offers information on the prevalence of addictive behaviours of the Internet, mobile phones and video game use. The problematic use of these ICT devices has been related to the consumption of drugs, poor academic performance and poor family relationships. This intensive use may constitute a risk marker for ICT addictio
Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC
The uncertainty on the calorimeter energy response to jets of particles is
derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the
calorimeter response to single isolated charged hadrons is measured and
compared to the Monte Carlo simulation using proton-proton collisions at
centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009
and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter
response to specific types of particles (positively and negatively charged
pions, protons, and anti-protons) is measured and compared to the Monte Carlo
predictions. Finally, the jet energy scale uncertainty is determined by
propagating the response uncertainty for single charged and neutral particles
to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3%
for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table,
submitted to European Physical Journal
Standalone vertex finding in the ATLAS muon spectrometer
A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011
Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC
Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson
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