40 results match your criteria: "Center for Optics and Photonics[Affiliation]"
BMC Plant Biol
February 2024
Laboratorio de Fisiología y Biotecnología Vegetal, Departamento de Ciencias Agropecuarias y Acuícolas, Facultad de Recursos Naturales, Universidad Católica de Temuco, P.O. Box 15-D, Temuco, Chile.
Background: Titanium dioxide nanoparticles (TiO NPs) have been reported to have contrasting effects on plant physiology, while their effects on sugar, protein, and amino acid metabolism are poorly understood. In this work, we evaluated the effects of TiO NPs on physiological and agronomical traits of tomato (Solanum lycopersicum L.) seedlings.
View Article and Find Full Text PDFJ Inorg Biochem
January 2018
Facultad de Estudios Superiores-Zaragoza, Universidad Nacional Autónoma de México, Batalla del 5 de Mayo y Fuerte de Loreto, Ciudad de México 09230, Mexico.
Two cytotoxic copper(II) complexes with N-H and N-methylated benzimidazole-derived ligands (Cu-L and Cu-L; L=bis(2-methylbenzimidazolyl)(2-methylthioethyl)amine, L=bis(1-methyl-2-methylbenzimidazolyl)(2-methylthioethyl)amine) were synthesized and exposed to human erythrocytes and molecular models of its membrane. The latter were bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), classes of lipids present in the external and internal moieties of the human red cell membrane, respectively. Scanning electron microscopy (SEM) of erythrocytes incubated with solutions of both Cu(II) complexes showed that they induced morphological changes to the normal cells to echinocytes, and hemolysis at higher concentrations.
View Article and Find Full Text PDFSci Rep
October 2017
Center for Optics and Photonics, Universidad de Concepción, Casilla, 4012, Concepción, Chile.
Digital photonic sensors have greatly evolved to maximize sensitivity and spatial, spectral, and temporal imaging resolution. For low-energy photons, new designs have generated new types of noise that degrade the formed-image signal-to-noise ratio to values lower than 1. Fixed-pattern noise (FPN), which is produced by the non-uniform focal-plane-array optoelectronics response, is an ill-posed problem in infrared and hyperspectral imaging science.
View Article and Find Full Text PDFBraz J Biol
January 2018
Center for Optics and Photonics, Universidad de Concepción - UdeC, Casilla 160-C, Concepción, Chile.
The Llanquihue lake is included in the called Araucanian or Nord Patagonian lakes located between 38-41° S. These lakes are characterized by their oligo-mesotrophic status due to human intervention which takes to the increase in nutrients inputs from industries and towns. Effects on zooplankton assemblages are observed with marked increase of daphnids abundance.
View Article and Find Full Text PDFPhys Rev Lett
March 2017
Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil.
Quantum mechanics forbids perfect discrimination among nonorthogonal states through a single shot measurement. To optimize this task, many strategies were devised that later became fundamental tools for quantum information processing. Here, we address the pioneering minimum-error (ME) measurement and give the first experimental demonstration of its application for discriminating nonorthogonal states in high dimensions.
View Article and Find Full Text PDFSci Bull (Beijing)
March 2017
Departamento de Física, MSI-Nucleus on Advanced Optics, and Center for Optics and Photonics (CEFOP), Facultad de Ciencias, Universidad de Chile, Santiago, Chile. Electronic address:
We experimentally study the transport properties of dipolar and fundamental modes on one dimensional (1D) coupled waveguide arrays. By carefully modulating a wide optical beam, we are able to effectively excite dipolar or fundamental modes to study discrete diffraction (single-site excitation) and gaussian beam propagation (multi-site excitation plus a phase gradient). We observe that dipolar modes experience a larger spreading area due to an effective larger coupling constant, which is found to be more than two times larger than the one for fundamental modes.
View Article and Find Full Text PDFPhys Rev Lett
December 2016
Departamento de Física, Universidad de Concepción, 160-C Concepción, Chile.
Quantum measurements on a two-level system can have more than two independent outcomes, and in this case, the measurement cannot be projective. Measurements of this general type are essential to an operational approach to quantum theory, but so far, the nonprojective character of a measurement can only be verified experimentally by already assuming a specific quantum model of parts of the experimental setup. Here, we overcome this restriction by using a device-independent approach.
View Article and Find Full Text PDFPhysiol Plant
May 2017
Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Technological Bioresource Nucleus (BIOREN), Universidad de La Frontera, Temuco, 54-D, Chile.
Despite the Montreal protocol and the eventual recovery of the ozone layer over Antarctica, there are still concerns about increased levels of ultraviolet-B (UV-B) radiation in the Southern Hemisphere. UV-B induces physiological, biochemical and morphological stress responses in plants, which are species-specific and different even for closely related cultivars. In woody plant species, understanding of long-term mechanisms to cope with UV-B-induced stress is limited.
View Article and Find Full Text PDFJ Membr Biol
December 2016
Malopolska Center of Biotechnology, Jagiellonian University, Kraków, Poland.
Thimerosal (THI, ethyl-mercury thiosalicylate) is added to vaccines as a preservative; as a consequence, infants may have been exposed to bolus doses of Hg that collectively added up to nominally 200 µg Hg during the first 6 months of life. While several studies report an association between THI-containing vaccines and neurological disorders, other studies do not support the causal relation between THI and autism. With the purpose to understand the molecular mechanisms of the toxic effect of THI it was assayed on human red cells and in bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), classes of phospholipids found in the outer and inner monolayers of the human erythrocyte membrane, respectively.
View Article and Find Full Text PDFJ Membr Biol
December 2016
Center for Optics and Photonics, University of Concepción, Concepción, Chile.
Gallic acid (GA) is a polyphenol present in many plants. This study was aimed to investigate the molecular interaction of GA with the human erythrocyte membrane and to determine its antioxidant capacity. The molecular interaction with the membrane of human red cells and the antioxidant property was assayed on both human red cells and molecular models of its membrane.
View Article and Find Full Text PDFSensors (Basel)
July 2016
Electrical Engineering Department, Universidad de Concepción, Edmundo Larenas 219, Concepción 4030000, Chile.
Images rendered by uncooled microbolometer-based infrared (IR) cameras are severely degraded by the spatial non-uniformity (NU) noise. The NU noise imposes a fixed-pattern over the true images, and the intensity of the pattern changes with time due to the temperature instability of such cameras. In this paper, we present a novel model and a compensation algorithm for the spatial NU noise and its temperature-dependent variations.
View Article and Find Full Text PDFPlant Physiol Biochem
October 2016
Departamento de Ciencias Químicas y Recursos Naturales, Facultad de Ingeniería y Ciencias, Universidad de La Frontera, P.O. Box 54-D, Temuco, Chile; Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Technological Bioresource Nucleus (BIOREN), Universidad de La Frontera, P.O. Box 54-D, Temuco, Chile.
The impact of increased artificial UV-B radiation on photosynthetic performance, antioxidant and SOD activities and molecular antioxidant metabolism responses in leaves of two highbush blueberry (Vaccinium corymbosum L. cv. Brigitta and Bluegold) genotypes was studied.
View Article and Find Full Text PDFBraz J Biol
January 2017
Center for Optics and Photonics, Universidad de Concepción - UdeC, Casilla 160-C, Concepción, Chile.
The fauna communities of ephemeral pools in southern Chile are characterized by heterogeneity of crustacean taxa; nevertheless, no detailed studies exist of their community structure. The aim of the present study was to analyze the crustacean community structure in two groups of ephemeral pools (Puaucho and Nigue pools) in the coastal zone of the Araucanía region. A correlation matrix was made by species abundance against temperature, conductivity, pH and total dissolved solids.
View Article and Find Full Text PDFPhys Rev E
March 2016
Departamento de Física, MSI-Nucleus on Advanced Optics, and Center for Optics and Photonics (CEFOP), Facultad de Ciencias, Universidad de Chile, Santiago, Chile.
We examine the transport of extended and localized excitations in one-dimensional linear chains populated by linear and nonlinear symmetric identical n-mers (with n=3, 4, 5, and 6), randomly distributed. First, we examine the transmission of plane waves across a single linear n-mer, paying attention to its resonances, and looking for parameters that allow resonances to merge. Within this parameter regime we examine the transmission of plane waves through a disordered and nonlinear segment composed by n-mers randomly placed inside a linear chain.
View Article and Find Full Text PDFAppl Spectrosc
April 2016
Department of Electrical Engineering, Universidad de Concepción, Concepción, Chile.
This work presents a non-parametric method based on a principal component analysis (PCA) and a parametric one based on artificial neural networks (ANN) to remove continuous baseline features from spectra. The non-parametric method estimates the baseline based on a set of sampled basis vectors obtained from PCA applied over a previously composed continuous spectra learning matrix. The parametric method, however, uses an ANN to filter out the baseline.
View Article and Find Full Text PDFJ Membr Biol
June 2016
Faculty of Exact and Natural Sciences, University of Antioquia, Medellín, Colombia.
In order to gain insight into the molecular mechanism of the antioxidant properties of Solanum crispum, aqueous extracts of its leaves were assayed on human erythrocytes and molecular models of its membrane. Phenolics and alkaloids were detected by HPLC-MS. Scanning electron and defocusing microscopy showed that S.
View Article and Find Full Text PDFJ Inorg Biochem
March 2016
Facultad de Estudios Superiores-Zaragoza, Universidad Nacional Autónoma de México, Batalla del 5 de Mayo y Fuerte de Loreto, México, D. F. 09230, Mexico.
Two cytotoxic copper(II) complexes with N-H and N-methylated benzimidazole-derived ligands (Cu-L(2) and Cu-L(2Me)) were synthesized and made to interact with human erythrocytes and molecular models of their plasmatic membranes. The latter consisted in lipid bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), lipids of the types present in the outer and inner monolayers of the human erythrocyte membrane, respectively. Initial assessment of the interaction of the complexes with DMPC and DMPE consisted of X-ray diffraction studies, which showed preferential interactions with the former.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
November 2015
Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden.
The localized mode propagation in binary nonlinear kagome ribbons is investigated with the premise to ensure controlled light propagation through photonic lattice media. Particularity of the linear system characterized by the dispersionless flat band in the spectrum is the opening of new minigaps due to the "binarism." Together with the presence of nonlinearity, this determines the guiding mode types and properties.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
September 2015
Departamento de Física and MSI-Nucleus on Advanced Optics, Center for Optics and Photonics (CEFOP), Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile.
We discuss the properties of nonlinear localized modes in sawtooth lattices, in the framework of a discrete nonlinear Schrödinger model with general on-site nonlinearity. Analytic conditions for existence of exact compact three-site solutions are obtained, and explicitly illustrated for the cases of power-law (cubic) and saturable nonlinearities. These nonlinear compact modes appear as continuations of linear compact modes belonging to a flat dispersion band.
View Article and Find Full Text PDFPhys Rev Lett
August 2015
Departamento de Física, Universidad de Concepción, Casilla 160-C, Concepción, Chile.
A long-standing problem in quantum mechanics is the minimum number of observables required for the characterization of unknown pure quantum states. The solution to this problem is especially important for the developing field of high-dimensional quantum information processing. In this work we demonstrate that any pure d-dimensional state is unambiguously reconstructed by measuring five observables, that is, via projective measurements onto the states of five orthonormal bases.
View Article and Find Full Text PDFBiochim Biophys Acta
November 2015
Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland; Malopolska Centre of Biotechnology, Jagiellonian University, Krakow, Poland.
Usnic acid (UA) has been associated with chronic diseases through its antioxidant action. Its main target is the cell membrane; however, its effect on that of human erythrocytes has been scarcely investigated. To gain insight into the molecular mechanisms of the interaction between UA and cell membranes human erythrocytes and molecular models of its membrane have been utilized.
View Article and Find Full Text PDFPhys Rev Lett
July 2015
Center for Optics and Photonics, Universidad de Concepción, Casilla 4016, Concepción, Chile.
Device-independent quantum communication will require a loophole-free violation of Bell inequalities. In typical scenarios where line of sight between the communicating parties is not available, it is convenient to use energy-time entangled photons due to intrinsic robustness while propagating over optical fibers. Here we show an energy-time Clauser-Horne-Shimony-Holt Bell inequality violation with two parties separated by 3.
View Article and Find Full Text PDFPhys Rev Lett
June 2015
Departamento de Física, MSI-Nucleus on Advanced Optics, and Center for Optics and Photonics (CEFOP), Facultad de Ciencias, Universidad de Chile, Santiago 7800003, Chile.
We present the first experimental demonstration of a new type of localized state in the continuum, namely, compacton-like linear states in flat-band lattices. To this end, we employ photonic Lieb lattices, which exhibit three tight-binding bands, with one being perfectly flat. Discrete predictions are confirmed by realistic continuous numerical simulations as well as by direct experiments.
View Article and Find Full Text PDFBiochim Biophys Acta
January 2015
Center for Optics and Photonics, University of Concepción, Chile.
Resveratrol (RV) is a potent antioxidant, anticancer and anti-inflammatory agent. Its main target of action is the cell membrane; however, its effect on that of human erythrocytes has been scarcely investigated. With the aim to better understand the molecular mechanisms of the interaction of RV with cell membranes both human erythrocytes and molecular models of its membrane have been utilized.
View Article and Find Full Text PDFPhys Rev Lett
August 2014
Departamento de Física, Universidad de Concepción, 160-C Concepción, Chile and Center for Optics and Photonics, Universidad de Concepción, 160-C Concepción, Chile and MSI-Nucleus for Advanced Optics, Universidad de Concepción, 160-C Concepción, Chile.
Kochen-Specker (KS) sets are key tools for proving some fundamental results in quantum theory and also have potential applications in quantum information processing. However, so far, their intrinsic complexity has prevented experimentalists from using them for any application. The KS set requiring the smallest number of contexts has been recently found.
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