125 research outputs found
Prótesis total de cadera con disco a compresión (PDC)
Se describe en este trabajo, un implante protésico total no
cementado de cadera, sin anclaje intramedular. Se estudia la
biomecánica de la articulación de la cadera, de los implantes
endomedulares y se marcan las características de la prótesis
PDC: transmisión de las fuerzas resultantes de la cadera directamente
al hueso cortical media1 del cuello femoral y la ausencia
de manipulación del canal medular. Por último se realiza una
somera descripción de la técnica de implantación
Fiber Bragg grating as an optical filter tuned by a magnetic field
We describe a novel tunable optical filter for use in optical-frequency-domain multiplexed communication
systems. The shift in the Bragg condition of a fiber Bragg grating as a result of magnetically induced circular
birefringence is calculated with coupled-mode theory on the basis of circular states of polarization, and the
values obtained for silica and terbium-doped optical fibers are compared
Single-longitudinal mode laser structure based on a very narrow filtering technique
A narrow filtering technique based on the spectral overlapping of two uniform FBGs and applied to obtain a Single Longitudinal Mode (SLM) laser is proposed and demonstrated in this work. The two FBGs are spectrally detuned to reduce their coincident reflection response narrowing the equivalent filter bandwidth. A proof-of-concept linear laser has been built and tested exhibiting SLM operation even with temperature and strain variations.The authors are grateful to the Spanish government project TEC2010-20224-C02, to the Spanish Ministry of Education and Culture, and to the grant AP2009-1403
Author Correction: Multifunctional light beam control device by stimuli-responsive liquid crystal micro-grating structures
Correction to: Scientific Reports https://doi.org/10.1038/s41598-020-70783-8, published online 14 August 2020
This Article contains a typographical error in the Acknowledgements section.
“the Ministerio de Economía y Competitividad of Spain (TEC2013-47342-C2-2-R)”
should read:
"the Ministerio de Economía y Competitividad of Spain (TEC2016-77242-C3-1-R)"This work was supported by the Comunidad de Madrid and FEDER Program (S2018/NMT-4326), the Ministerio de Economía y Competitividad of Spain (TEC2013-47342-C2-2-R and TEC2016-76021-C2-2-R), the FEDER/Ministerio de Ciencia, Innovación y Universidades and Agencia Estatal de Investigación (RTC2017-6321-1, PID2019-109072RB-C31 and PID2019-107270RB-C21). The authors also acknowledge the support by the Ministry of National Defense of Poland (GBMON/13-995/2018/WAT), Military University of Technology (Grant no. 23-895)
Analysis of detector performance in a gigahertz clock rate quantum key distribution system
We present a detailed analysis of a gigahertz clock rate environmentally robust phase-encoded quantum key distribution (QKD) system utilizing several different single-photon detectors, including the first implementation of an experimental resonant cavity thin-junction silicon single-photon avalanche diode. The system operates at a wavelength of 850 nm using standard telecommunications optical fibre. A general-purpose theoretical model for the performance of QKD systems is presented with reference to these experimental results before predictions are made about realistic detector developments in this system. We discuss, with reference to the theoretical model, how detector operating parameters can be further optimized to maximize key exchange rates
Ultrahigh temperature and strain hybrid integrated sensor system based on Raman and femtosecond FBG inscription in a multimode gold-coated fiber
In this paper, a novel approach for hybrid systems combining Raman distributed sensors with fiber Bragg grating (FBG) sensors to carry out distributed and quasi-distributed temperature/strain measurements was proposed and experimentally demonstrated. Three FBGs were inscribed by the point-by-point technique in a simple setup for type I femtosecond inscription in a pure silica core multimode gold-coated fiber. Employing a single fiber, temperatures up to 600 °C and strains up to 4144 µE approximately were measured simultaneously and without interferences between both distributed and point measurements. Moreover, a new calibration technique was implemented to calibrate the distributed temperature system using the FBG measurements as reference.Spanish Government FEDER Funds (TEC2016-76021-C2-2-R)
Immunotherapy moves to the early-stage setting in non-small cell lung cancer: emerging evidence and the role of biomarkers
Despite numerous advances in targeted therapy and immunotherapy in the last decade, lung cancer continues to present the highest mortality rate of all cancers. Targeted therapy based on specific genomic alterations, together with PD-1 and CTLA-4 axis blocking-based immunotherapy, have significantly improved survival in advanced non-small cell lung cancer (NSCLC) and both therapies are now well-established in this clinical setting. However, it is time for immunotherapy to be applied in patients with early-stage disease, which would be an important qualitative leap in the treatment of lung cancer patients with curative intent. Preliminary data from a multitude of studies are highly promising, but therapeutic decision-making should be guided by an understanding of the molecular features of the tumour and host. In the present review, we discuss the most recently published studies and ongoing clinical trials, controversies, future challenges and the role of biomarkers in the selection of best therapeutic options
Estudio físico, químico y microestructural de geopolímeros base ceniza volante
En este trabajo se analizó el comportamiento físico, químico y microestructural de la ceniza volante
activada alcalinamente. Para ello fueron utilizados diferentes tamaños de partícula de ceniza
volante (CV), obtenidos por molienda manual, mezcladas con NaOH y curadas durante 7, 14 y 28
días. Las técnicas de caracterización utilizadas fueron: TGA, FTIR, MEB, adsorción física de gases
y pruebas de resistencia a compresión, además del software NIVision Assistant.
Los resultados muestran que la disminución de tamaño de partículas, favoreció la
geopolimerización del gel N-A-S-H y mejoró las propiedades cementantes en los geopolímeros,
logrando resistencias a compresión hasta de 23 MPa, por otro lado, se indica mediante análisis de
imagen, que los porcentajes de porosidad en cada uno de los morteros evaluados disminuyen
conforme se alejan de la zona de transición interfacial (ZTI), los cuales se corroboran con los
resultados de porosimetría.
(ANGLÈS)
In this paper was analyzed the physical, chemical and microstructural behavior of alkali activated
fly ash. This comparison was used with different particle sizes of fly ash (CV), obtained by manual
milling, mixed with NaOH and cured for 7, 14 and 28 days. The characterization techniques used:
TGA, FTIR, SEM, physical adsorption of gases and compressive strength tests, as well NIVision
Assistant software.
The results show that decreasing particle size favored NASH gel Geopolymerization and improved
cementitious properties in geopolymer, achieving compressive strengths up to 23 MPa. On the
other hand, indicated by image analysis, the percentages of porosity in each of the mortars
evaluated decrease as they move away from the interfacial transition zone (ZTI), these results are
corroborated by porosimetry method.Peer ReviewedPostprint (published version
Negative responses of highland pines to anthropogenic activities in inland Spain: a palaeoecological perspective
Palaeoecological evidence indicates that highland pines were dominant in extensive areas of the mountains of Central and Northern Iberia during the first half of the Holocene. However, following several millennia of anthropogenic pressure, their natural ranges are now severely reduced. Although pines have been frequently viewed as first-stage successional species responding positively to human disturbance, some recent palaeobotanical work has proposed fire disturbance and human deforestation as the main drivers of this vegetation turnover. To assess the strength of the evidence for this hypothesis and to identify other possible explanations for this scenario, we review the available information on past vegetation change in the mountains of northern inland Iberia. We have chosen data from several sites that offer good chronological control, including palynological records with microscopic charcoal data and sites with plant macro- and megafossil occurrence. We conclude that although the available long-term data are still fragmentary and that new methods are needed for a better understanding of the ecological history of Iberia, fire events and human activities (probably modulated by climate) have triggered the pine demise at different locations and different temporal scales. In addition, all palaeoxylological, palynological and charcoal results obtained so far are fully compatible with a rapid human-induced ecological change that could have caused a range contraction of highland pines in western Iberia
A Next-Generation Liquid Xenon Observatory for Dark Matter and Neutrino Physics
The nature of dark matter and properties of neutrinos are among the mostpressing issues in contemporary particle physics. The dual-phase xenontime-projection chamber is the leading technology to cover the availableparameter space for Weakly Interacting Massive Particles (WIMPs), whilefeaturing extensive sensitivity to many alternative dark matter candidates.These detectors can also study neutrinos through neutrinoless double-beta decayand through a variety of astrophysical sources. A next-generation xenon-baseddetector will therefore be a true multi-purpose observatory to significantlyadvance particle physics, nuclear physics, astrophysics, solar physics, andcosmology. This review article presents the science cases for such a detector.<br
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