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81.
Angel MunToz-Ruiz Rafael Gallego Manuel del Pozo MA Rosa Jim nez-Castellanos Jos Domí nguez-Abascal 《Drug development and industrial pharmacy》1995,21(2):215-227
In this paper a determination of the possible sources of experimental errors of displacement measurements by an instrumented single-punch machine and their repercussion in compression parameters has been accomplished. Also, elastic deformation of punches and other parts of the machine was evaluated using three different methods. One of these, based on the strain gauge response as measure of punch deformation it is proposed as a novel method to correct displacement measurements by instrumented machines. 相似文献
82.
A cooperative game for a set of agents establishes a fair allocation of the profit obtained for their cooperation. In order to obtain this allocation, a characteristic function is known. It establishes the profit of each coalition of agents if this coalition decides to act alone. Originally players are considered symmetric and then the allocation only depends on the characteristic function; this paper is about cooperative games with an asymmetric set of agents. We introduced cooperative games with a soft set of agents which explains those parameters determining the asymmetry among them in the cooperation. Now the characteristic function is defined not over the coalitions but over the soft coalitions, namely the profit depends not only on the formed coalition but also on the attributes considered for the players in the coalition. The best known of the allocation rules for cooperative games is the Shapley value. We propose a Shapley kind solution for soft games. 相似文献
83.
Jorge Francés Sergio Bleda Andrés Márquez Cristian Neipp Sergi Gallego Beatriz Otero Augusto Beléndez 《The Journal of supercomputing》2014,70(2):514-526
In this work a unified treatment of solid and fluid vibration problems is developed by means of the Finite-Difference Time-Domain (FDTD). The scheme here proposed takes advantage from a scaling factor in the velocity fields that improves the performance of the method and the vibration analysis in heterogenous media. Moreover, the scheme has been extended in order to simulate both the propagation in porous media and the lossy solid materials. In order to accurately reproduce the interaction of fluids and solids in FDTD both time and spatial resolutions must be reduced compared with the set up used in acoustic FDTD problems. This aspect implies the use of bigger grids and hence more time and memory resources. For reducing the time simulation costs, FDTD code has been adapted in order to exploit the resources available in modern parallel architectures. For CPUs the implicit usage of the advanced vectorial extensions (AVX) in multi-core CPUs has been considered. In addition, the computation has been distributed along the different cores available by means of OpenMP directives. Graphic Processing Units have been also considered and the degree of improvement achieved by means of this parallel architecture has been compared with the highly-tuned CPU scheme by means of the relative speed up. The speed up obtained by the parallel versions implemented were up to 3 (AVX and OpenMP) and 40 (CUDA) times faster than the best sequential version for CPU that also uses OpenMP with auto-vectorization techniques, but non includes implicitely vectorial instructions. Results obtained with both parallel approaches demonstrate that massive parallel programming techniques are mandatory in solid-vibration problems with FDTD. 相似文献
84.
Francisco Gallego‐Gómez Eva M. García‐Frutos José M. Villalvilla José A. Quintana Enrique Gutierrez‐Puebla Angeles Monge María A. Díaz‐García Berta Gómez‐Lor 《Advanced functional materials》2011,21(4)
A new carbazole‐related small molecule exhibiting self‐assembly into ordered nanostructures in solution‐processed cast films has been synthesized and its charge‐photogeneration and ‐transport properties have been investigated. Large photoconductivity was measured in the amorphous state while an enormous improvement in the photoconduction properties was observed when the molecules spontaneously organized. Photocurrents increased upon self‐assembly by up to four orders of magnitude, mostly due to the drastic enhancement of the charge photogeneration. A greatly favorable arrangement of the aromatic cores in the resulting nanostructures, which were characterized by X‐ray analysis, may explain these improvements. Photocurrents of mA cm?2, on/off ratios of 104 and quantum efficiencies of unity at low field and light intensity, which are among the best values reported to date, along with the simplicity of fabrication, give this readily‐available organic system great potential for use in plastic optoelectronic devices. 相似文献
85.
The internal friction spectra of high purity aluminium (99.999%) has been thoroughly studied but, at the present time, there is no agreement about the number of peaks at medium temperatures and the number of components of each peak. This paper discusses the reasons for that controversy and summarizes the relaxation processes found in the internal friction spectra. Some authors have assumed that the P2 peak (also called Kê peak) is formed by two components, one associated to a mechanism of dislocation mobility and the other to grain boundary sliding. However, this assertion is based on weak experimental evidence, which is critically reviewed in this work. The fitting methods used to decompose the internal friction spectra have also been discussed, since some of them can generate spurious components and lead to equivocal conclusions. Another point of great interest that has remained unclear concerns the shifts of the temperature of the peaks observed by many authors, which are explained in this paper with the help of some mechanisms of dislocation mobility. Several specific experimental measurements in 99.999% aluminium and 99.9999% aluminium doped with 10 ppm of copper are presented to clarify these questions. It is concluded that P2 is composed of just one component and is associated to a mechanism of dislocation mobility. In addition, we have determined that there are only three peaks in the medium temperature range, namely P1, P2 and P3. 相似文献
86.
Eva Jimnez-Mora Beatriz Gallego Sergio Díaz-Gago Marina Lasa Pablo Baquero Antonio Chiloeches 《International journal of molecular sciences》2021,22(11)
The dysregulation of autophagy is important in the development of many cancers, including thyroid cancer, where V600EBRAF is a main oncogene. Here, we analyse the effect of V600EBRAF inhibition on autophagy, the mechanisms involved in this regulation and the role of autophagy in cell survival of thyroid cancer cells. We reveal that the inhibition of V600EBRAF activity with its specific inhibitor PLX4720 or the depletion of its expression by siRNA induces autophagy in thyroid tumour cells. We show that V600EBRAF downregulation increases LKB1-AMPK signalling and decreases mTOR activity through a MEK/ERK-dependent mechanism. Moreover, we demonstrate that PLX4720 activates ULK1 and increases autophagy through the activation of the AMPK-ULK1 pathway, but not by the inhibition of mTOR. In addition, we find that autophagy blockade decreases cell viability and sensitize thyroid cancer cells to V600EBRAF inhibition by PLX4720 treatment. Finally, we generate a thyroid xenograft model to demonstrate that autophagy inhibition synergistically enhances the anti-proliferative and pro-apoptotic effects of V600EBRAF inhibition in vivo. Collectively, we uncover a new role of AMPK in mediating the induction of cytoprotective autophagy by V600EBRAF inhibition. In addition, these data establish a rationale for designing an integrated therapy targeting V600EBRAF and the LKB1-AMPK-ULK1-autophagy axis for the treatment of V600EBRAF-positive thyroid tumours. 相似文献
87.
Raúl Ferrer‐Gallego Julián C Rivas‐Gonzalo M Teresa Escribano‐Bailón 《Journal of the science of food and agriculture》2013,93(4):967-972
BACKGROUND: Interest in high‐quality products with a clear geographical origin is increasing. For the wine industry and market sector, identity preservation is of fundamental importance owing to the large number of geographical classifications. Nowadays, there is a growing demand for analytical methods for tracing grapes and wines. In the oenological sector, infrared spectroscopy is becoming an attractive tool allowing simultaneous measurement of several analytical parameters and enabling real‐time decision making. RESULTS: Discriminant partial least squares, a supervised pattern recognition technique, was employed to discriminate between vineyards of origin using the near‐infrared spectra of intact grapes, skins or seeds. In order to compare the three sample presentations, a receiver operating characteristic curve was used. The best results were obtained using intact grape seeds, with prediction rates of samples correctly classified of about 95%, although the good results obtained with entire grapes (about 93% of samples correctly classified) and the simplicity of use of the fibre optic probe could advise using entire grape presentation for comprehensive studies. CONCLUSION: The procedure reported here seems to have excellent potential for a fast and reasonably inexpensive analysis of the origin of samples. It is noted that such classification can be made at any time of ripening. This paper provides information of interest to develop new and extensive models in the future. © 2012 Society of Chemical Industry 相似文献
88.
H. Ivankovic E. Tkalcec S. Orlic G. Gallego Ferrer Z. Schauperl 《Journal of materials science. Materials in medicine》2010,21(10):2711-2722
Highly porous hydroxyapatite (Ca10(PO4)6·(OH)2, HA) was prepared through hydrothermal transformation of aragonitic cuttlefish bones (Sepia officinalis L. Adriatic Sea) in the temperature range from 140 to 220°C for 20 min to 48 h. The phase composition of converted hydroxyapatite
was examined by quantitative X-ray diffraction (XRD) using Rietveld structure refinement and Fourier transform infrared spectroscopy
(FTIR). Johnson–Mehl–Avrami (JMA) approach was used to follow the kinetics and mechanism of transformation. Diffusion controlled
one dimensional growth of HA, predominantly along the a-axis, could be defined. FTIR spectroscopy determined B-type substitutions of CO3
2− groups. The morphology and microstructure of converted HA was examined by scanning electron microscopy. The general architecture
of cuttlefish bones was preserved after hydrothermal treatment and the cuttlefish bones retained its form with the same channel
size (~80 × 300 μm). The formation of dandelion-like HA spheres with diameter from 3 to 8 μm were observed on the surface
of lamellae, which further transformed into various radially oriented nanoplates and nanorods with an average diameter of
about 200–300 nm and an average length of about 8–10 μm. 相似文献
89.
A major component of the Joint Research Centre's TREES-II project is the assessment of deforestation rates in moist tropical regions for the period 1992 to 1997 using a statistical sample of fine spatial resolution satellite image pairs. It is widely recognized that spatial stratification can reduce the variance of estimates in spatial sampling designs. However, at the pan-tropical scale little reliable spatial information is available to stratify on the basis of deforestation rates. This paper describes a novel sampling scheme for assessing tropical deforestation rates. Stratification is performed using percentages of forest area (derived from National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) data) and areas of known deforestation activity (elucidated from expert consultation) estimated for each sampling unit. Sample site selection is performed by using a sample frame based on a tessellation of hexagons on a sphere. This approach allows for a sensor-independent sample from which unbiased estimators and error variance may be computed. The scheme is currently in the implementation phase for the tropical belt, but can be extended to the global scale. 相似文献
90.
Juan A. Pajares Gonzalo Álvarez Fernando Ibeas Diego Gallego David R. Hall Dudley I. Farman 《Journal of chemical ecology》2010,36(6):570-583
The pine sawyer beetle, Monochamus galloprovincialis, is a pest of pine trees in Europe and North Africa. Previously considered a secondary pest of stressed and dying trees,
it is now receiving considerable attention as a vector of the pine wood nematode, Bursaphelenchus xylophilus, the causal agent of a lethal wilting disease in susceptible species of pines. Adult beetles are attracted to traps baited
with a kairomone blend consisting of a host volatile, α-pinene, and two bark beetle pheromone components, ipsenol and 2-methyl-3-buten-2-ol.
More recently it has been shown that mature male M. galloprovincialis produce a pheromone that attracts mature females in a laboratory bioassay. Here, volatiles were collected from mature male
and female M. galloprovincialis, and a compound produced specifically by mature males was identified as 2-undecyloxy-1-ethanol from its gas chromatographic
retention times, its mass spectrum, and by comparison with synthetic standards. The naturally-derived and synthetic compounds
elicited electroantennographic responses from both females and males. Sealed polyethylene vials and polyethylene sachets were
shown to be effective dispensers with zero-order release, the latter giving a higher release rate than the former. In two
field tests, multiple-funnel traps baited with synthetic 2-undecyloxy-1-ethanol caught both female and male M. galloprovincialis, with higher catches at the higher release rate. This compound also synergized the attractiveness of the kairomone blend,
the combined mixture catching 80–140% more beetles than the sum of the catches to each bait separately and luring up to two
beetles/trap/d in a moderate-density population. We conclude that 2-undecyloxy-1-ethanol is a male-produced aggregation pheromone
of M. galloprovincialis. This is the first example of a sex-specific compound in the cerambycid subfamily Lamiinae with significant behavioral activity
in the field at a range sufficient to make it a useful trap bait. The possible roles of this pheromone in the chemical ecology
of M. galloprovincialis and its potential use in pine wilt disease management are discussed. 相似文献