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51.
Nowadays, cities are the most relevant type of human settlement and their population has been endlessly growing for decades. At the same time, we are witnessing an explosion of digital data that capture many different aspects and details of city life. This allows detecting human mobility patterns in urban areas with more detail than ever before. In this context, based on the fusion of mobility data from different and heterogeneous sources, such as public transport, transport‐network connectivity and Online Social Networks, this study puts forward a novel approach to uncover the actual land use of a city. Unlike previous solutions, our work avoids a time‐invariant approach and it considers the temporal factor based on the assumption that urban areas are not used by citizens all the time in the same manner. We have tested our solution in two different cities showing high accuracy rates. 相似文献
52.
Shin-Ting W Yasuda CL Cendes F 《IEEE transactions on visualization and computer graphics》2012,18(2):299-308
Curvilinear reformatting of 3D magnetic resonance imaging data has been recognized by the medical community as a helpful noninvasive tool for displaying the cerebral anatomy. It consists of automatically creating, with respect to a reference surface, a series of equidistant curvilinear slices at progressively deeper cuts. In comparison with planar slices, it allows more precise localization of lesions and identification of subtle structural abnormalities. However, current curvilinear reformatting tools either rely on the time-consuming manual delineation of guiding curves on 2D slices, or require costly automatic brain segmentation procedures. In addition, they extract the skin and skull, impeding a precise topographic correlation between the location of the brain lesion and skin surface. This impairs planning of craniotomy for neurosurgery, and of the appropriate implantation of electrodes for intracranial electroencephalography in presurgical evaluation. In this work, we present a novel approach based on direct manipulation of the visualized volume data. By using a 3D painting metaphor, the reference surface can be defined incrementally, according to the principle that the user interacts with what she/he sees. As a response, an animation of the reformatting process is displayed. The focus of this paper is a new volume tagging algorithm behind user interactions. It works at an interactive frame rate on current graphics hardware. 相似文献
53.
Javier Cuadrado Daniel Dopico Jose A. Perez Roland Pastorino 《Multibody System Dynamics》2012,27(1):3-19
This work is part of a project aimed to develop automotive real-time observers based on detailed nonlinear multibody models
and the extended Kalman filter (EKF). In previous works, a four-bar mechanism was studied to get insight into the problem.
Regarding the formulation of the equations of motion, it was concluded that the state-space reduction method known as matrix-R
is the most suitable one for this application. Regarding the sensors, it was shown that better stability, accuracy and efficiency
are obtained as the sensored magnitude is a lower derivative and when it is a generalized coordinate of the problem. In the
present work, the automotive problem has been addressed, through the selection of a Volkswagen Passat as a case-study. A model
of the car containing fifteen degrees of freedom has been developed. The observer algorithm that combines the equations of
motion and the integrator has been reformulated so that duplication of the problem size is avoided, in order to improve efficiency.
A maneuver of acceleration from rest and double lane change has been defined, and tests have been run for the “prototype,”
the “model” and the “observer,” all the three computational, with the model having 100 kg more than the prototype. Results
have shown that good convergence is obtained for position level sensors, but the computational cost is high, still far from
real-time performance. 相似文献
54.
55.
Quantitative real-time imaging of myocardium based on ultrasonic integrated backscatter 总被引:5,自引:0,他引:5
Thomas LJ Barzilai B Perez JE Sobel BE Wickline SA Miller JG 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1989,36(4):466-470
The integrated backscatter calculation over the full, two-dimensional echocardiographic sector is implemented to produce images from closed-chest dogs. This new real-time integrated backscatter measurement system allows a continuous determination of integrated backscatter from all myocardial regions in the ultrasonic view. By replacing the conventional video processor in a commercial two-dimensional echocardiographic imager with this new real-time backscatter measurement system, it is possible to produce real-time two-dimensional images based on integrated backscatter. 相似文献
56.
Improved Controlled Release and Brain Penetration of the Small Molecule S14 Using PLGA Nanoparticles
Vanesa Nozal Elisa Rojas-Prats Ins Maestro Carmen Gil Daniel I. Perez Ana Martinez 《International journal of molecular sciences》2021,22(6)
Phosphodiesterase 7 (PDE7) is an enzyme responsible for the degradation of cyclic adenosine monophosphate (cAMP), an important cellular messenger. PDE7’s role in neurotransmission, expression profile in the brain and the druggability of other phosphodiesterases have motivated the search for potent inhibitors to treat neurodegenerative and inflammatory diseases. Different heterocyclic compounds have been described over the years; among them, phenyl-2-thioxo-(1H)-quinazolin-4-one, called S14, has shown very promising results in different in vitro and in vivo studies. Recently, polymeric nanoparticles have been used as new formulations to target specific organs and produce controlled release of certain drugs. In this work, we describe poly(lactic-co-glycolic acid) (PLGA)-based polymeric nanoparticles loaded with S14. Their preparation, optimization, characterization and in vivo drug release profile are here presented as an effort to improve pharmacokinetic properties of this interesting PDE7 inhibitor. 相似文献
57.
Delfino Chamorro-Arenas Giovanna Salgado-Moreno Dr. Liliana Martinez-Mendieta Dr. Leticia Quintero Dr. Beatriz Godínez-Chaparro Prof. Fernando Sartillo-Piscil 《ChemMedChem》2021,16(3):472-476
The design, stereoselective synthesis and in vivo antiallodynic activity of four novel paroxetine analogs, named 3-hydroxy paroxetines (3HPXs), is reported herein. Among the novel synthesized compounds, three showed an antiallodynic effect, while (R,R)-3HPX was found to be 2.5 times more bioactive than (-)-paroxetine itself in neuropathic rats. Consequently, the current investigation not only discloses a novel promising analgesic drug, but also reveals that functionalization at the C3 position of paroxetine could be as effective as the common functionalization at either C4 or within the sesamol group. 相似文献
58.
Hormone signaling plays a pivotal role in plant–microbe interactions. There are three major phytohormones in plant defense: salicylic acid (SA), jasmonic acid (JA), and ethylene (ET). The activation and trade-off of signaling between these three hormones likely determines the strength of plant defense in response to pathogens. Here, we describe the allocation of hormonal signaling in Brassica napus against the fungal pathogen Leptosphaeria maculans. Three B. napus genotypes (Westar, Surpass400, and 01-23-2-1) were inoculated with two L. maculans isolates (H75 8-1 and H77 7-2), subsequently exhibiting three levels of resistance: susceptible, intermediate, and resistant. Quantitative analyses suggest that the early activation of some SA-responsive genes, including WRKY70 and NPR1, contribute to an effective defense against L. maculans. The co-expression among factors responding to SA/ET/JA was also observed in the late stage of infection. The results of conjugated SA measurement also support that early SA activation plays a crucial role in durable resistance. Our results demonstrate the relationship between the onset patterns of certain hormone regulators and the effectiveness of the defense of B. napus against L. maculans. 相似文献
59.
Fernando Corvillo Laura Gonzlez-Snchez Alberto Lpez-Lera Emilia Arjona Giovanni Ceccarini Ferruccio Santini David Araújo-Vilar Rebecca J Brown Joan Villarroya Francesc Villarroya Santiago Rodríguez de Crdoba Teresa Caballero Pilar Nozal Margarita Lpez-Trascasa 《International journal of molecular sciences》2021,22(12)
60.
Sara M. dos S. Pizzatto Fernando Otavio Pizzatto Elidio Angioletto Sabrina Arcaro Eduardo Junca Oscar R. Klegues Montedo 《International Journal of Applied Ceramic Technology》2021,18(5):1734-1742
The effects of porous ceramic plates on the thermal behavior of ventilated façades were evaluated, and the results are presented herein. Thermal behavior in a ventilated façade of specimens containing 40 wt% of lime mud and a firing temperature of 1100°C was evaluated and compared with a commercial porcelain ceramic tile, which was the reference material. An experimental apparatus was designed to evaluate the thermal performance of the studied ventilated façades. The results revealed that the ventilated façade composed of the studied porous ceramic tiles produced a greater reduction in temperature between the external environmental and the interior of a box representing a building (ΔT5) of 65.7°C, compared with the façade composed of the commercial porcelain ceramic tiles (ΔT5 = 56.0°C) and even the traditional façade (ΔT5 = 49.1°C). Thus, porous ceramic tiles based on byproducts are promising candidates for ventilated façade systems. 相似文献