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1.
Sci Rep ; 10(1): 13083, 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753626

RESUMO

Emergent technologies that make use of novel materials and quantum properties of light states are at the forefront in the race for the physical implementation, encoding and transmission of information. Photonic crystals (PCs) enter this paradigm with optical materials that allow the control of light propagation and can be used for optical communication, and photonics and electronics integration, making use of materials ranging from semiconductors, to metals, metamaterials, and topological insulators, to mention but a few. Here, we show how designer superconductor materials integrated into PCs fabrication allow for an extraordinary reduction of electromagnetic waves damping, making possible their optimal propagation and tuning through the structure, below critical superconductor temperature. We experimentally demonstrate, for the first time, a successful integration of ferroelectric and superconductor materials into a one-dimensional (1D) PC composed of [Formula: see text] bilayers that work in the whole visible spectrum, and below (and above) critical superconductor temperature [Formula: see text]. Theoretical calculations support, for different number of bilayers N, the effectiveness of the produced 1D PCs and may pave the way for novel optoelectronics integration and information processing in the visible spectrum, while preserving their electric and optical properties.

2.
J Phys Chem A ; 122(43): 8469-8476, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30350632

RESUMO

Push-pull functional compounds consisting of dicyanorhodanine derivatives have attracted a lot of interest because their optical, electronic, and charge transport properties make them useful as building blocks for organic photovoltaic implementations. The analysis of the frontier molecular orbitals shows that the vertical transitions of electronic absorption are characterized as intramolecular charge transfer; furthermore, we show that the analyzed compounds exhibit bathochromic displacements when comparing the presence (or absence) of solvent as an interacting medium. In comparison with materials defined by their energy of reorganization of electrons (holes) as electron (hole) transporters, we find a transport hierarchy whereby the molecule ( Z)-2-(1,1-dicyanomethylene)-5-[(4-dimethylamino)benzylidene]-1,3-thiazol-4 is better at transporting holes than molecule ( Z)-2-(1,1-dicyanomethylene)-5-(tetrathiafulvalene-2-ylidene)-1,3-thiazol-4.

3.
Sensors (Basel) ; 17(8)2017 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-28796177

RESUMO

In this paper, we address the generation of semantic labels describing the headgear accessories carried out by people in a scene under surveillance, only using depth information obtained from a Time-of-Flight (ToF) camera placed in an overhead position. We propose a new method for headgear accessories classification based on the design of a robust processing strategy that includes the estimation of a meaningful feature vector that provides the relevant information about the people's head and shoulder areas. This paper includes a detailed description of the proposed algorithmic approach, and the results obtained in tests with persons with and without headgear accessories, and with different types of hats and caps. In order to evaluate the proposal, a wide experimental validation has been carried out on a fully labeled database (that has been made available to the scientific community), including a broad variety of people and headgear accessories. For the validation, three different levels of detail have been defined, considering a different number of classes: the first level only includes two classes (hat/cap, and no hat/cap), the second one considers three classes (hat, cap and no hat/cap), and the last one includes the full class set with the five classes (no hat/cap, cap, small size hat, medium size hat, and large size hat). The achieved performance is satisfactory in every case: the average classification rates for the first level reaches 95.25%, for the second one is 92.34%, and for the full class set equals 84.60%. In addition, the online stage processing time is 5.75 ms per frame in a standard PC, thus allowing for real-time operation.

4.
Sci Rep ; 7: 44730, 2017 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-28327567

RESUMO

Game theory is a well established branch of mathematics whose formalism has a vast range of applications from the social sciences, biology, to economics. Motivated by quantum information science, there has been a leap in the formulation of novel game strategies that lead to new (quantum Nash) equilibrium points whereby players in some classical games are always outperformed if sharing and processing joint information ruled by the laws of quantum physics is allowed. We show that, for a bipartite non zero-sum game, input local quantum correlations, and separable states in particular, suffice to achieve an advantage over any strategy that uses classical resources, thus dispensing with quantum nonlocality, entanglement, or even discord between the players' input states. This highlights the remarkable key role played by pure quantum coherence at powering some protocols. Finally, we propose an experiment that uses separable states and basic photon interferometry to demonstrate the locally-correlated quantum advantage.

5.
Med. clín (Ed. impr.) ; 137(6): 273-277, sept. 2011.
Artigo em Espanhol | IBECS | ID: ibc-92191

RESUMO

Los factores de transferencia (FT) son mensajeros peptídicos producidos por linfocitos T activados como parte de la inmunidad celular que actúa en linfocitos vírgenes a través de FT inductores, supresores y específicos de antígeno. Los FT no son inmunógenos porque no son específicos de especie, ya que contienen una secuencia consenso de aminoácidos LLYAQDL/VEDN. De igual manera, el FT extraído de leucocitos de los humanos puede transferir inmunidad de una a otra especie. Los extractos del FT son complejos y contienen más de 200 moléculas con pesos moleculares de 1–20kDa. Los factores de transferencia específicos de antígeno (FTE) tienen pesos moleculares entre 3,5–5kDa. El FT es fácil de preparar, es bien tolerado y no contiene antígenos HL-A contra los que el receptor pueda reaccionar; además, pueden utilizarse como terapia coadyuvante en diversas enfermedades (AU)


Assuntos
Humanos , Fator de Transferência/análise , Antineoplásicos/farmacocinética , Neoplasias/tratamento farmacológico , Fator 1 de Ligação ao Facilitador Linfoide/análise , Anticorpos Fosfo-Específicos/análise
6.
Med Clin (Barc) ; 137(6): 273-7, 2011 Sep 10.
Artigo em Espanhol | MEDLINE | ID: mdl-20561650

RESUMO

Transfer factor (TF) consists of messenger peptides produced by activated T lymphocytes as part of cellular immunity, and it acts in virgin lymphocytes through TF inducers, suppressors and specific antigens. TF is not immunogenic because it is not species-specific, since it contains a consensus sequence of amino acids LLYAQDL/VEDN. TF extracted from leukocytes can transfer immunity from a human to another species. TF extracts are complex, containing more than 200 molecules with molecular weights ranging from 1 to 20 kDa. The antigen specific transfer factors (STF) have molecular weights between 3,5 and 5 kDa. TF is easy to prepare and well tolerated. It does not contain HL-A antigens against potential receptors and it can used as adjuvant therapy in several diseases.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Fator de Transferência/uso terapêutico , Antineoplásicos/uso terapêutico , Ensaios Clínicos como Assunto , Colostro/química , Sequência Consenso , Método Duplo-Cego , Humanos , Ativação Linfocitária , Esclerose Múltipla/tratamento farmacológico , Neoplasias/tratamento farmacológico , Linfócitos T/metabolismo , Fator de Transferência/química , Fator de Transferência/isolamento & purificação , Fator de Transferência/fisiologia , Resultado do Tratamento , Tuberculose/tratamento farmacológico
7.
Sensors (Basel) ; 10(5): 4825-37, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22363203

RESUMO

In this paper, a new method of classification and localization of reflectors, using the time-of-flight (TOF) data obtained from ultrasonic transducers, is presented. The method of classification and localization is based on Generalized Principal Component Analysis (GPCA) applied to the TOF values obtained from a sensor that contains four ultrasound emitters and 16 receivers. Since PCA works with vectorized representations of TOF, it does not take into account the spatial locality of receivers. The GPCA works with two-dimensional representations of TOF, taking into account information on the spatial position of the receivers. This report includes a detailed description of the method of classification and localization and the results of achieved tests with three types of reflectors in 3-D environments: planes, edges, and corners. The results in terms of processing time, classification and localization were very satisfactory for the reflectors located in the range of 50-350 cm.

8.
Sensors (Basel) ; 9(11): 8810-23, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22291537

RESUMO

A sensor system to measure the 2-D position of an object that intercepts a plane in space is presented in this paper. This sensor system was developed with the aim of measuring the height and lateral position of contact wires supplying power to electric locomotives. The sensor comprises two line-scans focused on the zone to be measured and positioned in such a way that their viewing planes are on the same plane. The report includes a mathematical model of the sensor system, and details the method used for calibrating the sensor system. The procedure used for high speed measurement of object position in space is also described, where measurement acquisition time was less than 0.7 ms. Finally, position measurement results verifying system performance in real time are given.

9.
Sensors (Basel) ; 9(12): 10434-46, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22303183

RESUMO

In this paper, the problem of how to estimate the distance between an infrared emitter diode (IRED) and a camera from pixel grey-level intensities is examined from a practical standpoint. Magnitudes that affect grey level intensity were defined and related to the zero frequency component from the FFT image. A general model was also described and tested for distance estimation over the range from 420 to 800 cm using a differential methodology. Method accuracy is over 3%.

10.
Sensors (Basel) ; 9(10): 8215-29, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22408502

RESUMO

Image transmission using incoherent optical fiber bundles (IOFB) requires prior calibration to obtain the spatial in-out fiber correspondence in order to reconstruct the image captured by the pseudo-sensor. This information is recorded in a Look-Up Table (LUT), used later for reordering the fiber positions and reconstructing the original image. This paper presents a method based on line-scan to obtain the in-out correspondence. The results demonstrate that this technique yields a remarkable reduction in processing time and increased image quality by introducing a fiber detection algorithm, an intensity compensation process and finally, a single interpolation algorithm.

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