181 research outputs found
Real-Time and Low-Cost Sensing Technique Based on Photonic Bandgap Structures
This paper was published in OPTICS LETTERS and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OL.36.002707. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law[EN] A technique for the development of low-cost and high-sensitivity photonic biosensing devices is proposed and experimentally demonstrated. In this technique, a photonic bandgap structure is used as transducer, but its readout is performed by simply using a broadband source, an optical filter, and a power meter, without the need of obtaining the transmission spectrum of the structure; thus, a really low-cost system and real-time results are achieved. Experimental results show that it is possible to detect very low refractive index variations, achieving a detection limit below 2 x 10(-6) refractive index units using this low-cost measuring technique. (C) 2011 Optical Society of America[This work was funded by the Spanish Ministerio de Ciencia e Innovacion (MICINN) under contracts TEC2008-06333, JCI-009-5805, and TEC2008-05490. Support by the Universidad Politecnica de Valencia through program PAID-06-09 and the Conselleria d'Educacio through program GV-2010-031 is acknowledged.García Castelló, J.; Toccafondo, V.; Pérez Millán, P.; Sánchez Losilla, N.; Cruz, JL.; Andres, MV.; García-Rupérez, J. (2011). Real-Time and Low-Cost Sensing Technique Based on Photonic Bandgap Structures. Optics Letters. 36(14):2707-2709. https://doi.org/10.1364/OL.36.002707S270727093614Fan, X., White, I. M., Shopova, S. I., Zhu, H., Suter, J. D., & Sun, Y. (2008). Sensitive optical biosensors for unlabeled targets: A review. 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IEEE Journal of Selected Topics in Quantum Electronics, 16(3), 654-661. doi:10.1109/jstqe.2009.2032510Xu, D.-X., Vachon, M., Densmore, A., Ma, R., Delâge, A., Janz, S., … Schmid, J. H. (2010). Label-free biosensor array based on silicon-on-insulator ring resonators addressed using a WDM approach. Optics Letters, 35(16), 2771. doi:10.1364/ol.35.002771Skivesen, N., Têtu, A., Kristensen, M., Kjems, J., Frandsen, L. H., & Borel, P. I. (2007). Photonic-crystal waveguide biosensor. Optics Express, 15(6), 3169. doi:10.1364/oe.15.003169Lee, M. R., & Fauchet, P. M. (2007). Nanoscale microcavity sensor for single particle detection. Optics Letters, 32(22), 3284. doi:10.1364/ol.32.003284García-Rupérez, J., Toccafondo, V., Bañuls, M. J., Castelló, J. G., Griol, A., Peransi-Llopis, S., & Maquieira, Á. (2010). Label-free antibody detection using band edge fringes in SOI planar photonic crystal waveguides in the slow-light regime. Optics Express, 18(23), 24276. doi:10.1364/oe.18.024276Toccafondo, V., García-Rupérez, J., Bañuls, M. J., Griol, A., Castelló, J. G., Peransi-Llopis, S., & Maquieira, A. (2010). Single-strand DNA detection using a planar photonic-crystal-waveguide-based sensor. Optics Letters, 35(21), 3673. doi:10.1364/ol.35.003673Luff, B. J., Wilson, R., Schiffrin, D. J., Harris, R. D., & Wilkinson, J. S. (1996). Integrated-optical directional coupler biosensor. Optics Letters, 21(8), 618. doi:10.1364/ol.21.000618Sepúlveda, B., Río, J. S. del, Moreno, M., Blanco, F. J., Mayora, K., Domínguez, C., & Lechuga, L. M. (2006). Optical biosensor microsystems based on the integration of highly sensitive Mach–Zehnder interferometer devices. Journal of Optics A: Pure and Applied Optics, 8(7), S561-S566. doi:10.1088/1464-4258/8/7/s41Densmore, A., Vachon, M., Xu, D.-X., Janz, S., Ma, R., Li, Y.-H., … Schmid, J. H. (2009). Silicon photonic wire biosensor array for multiplexed real-time and label-free molecular detection. Optics Letters, 34(23), 3598. doi:10.1364/ol.34.003598Povinelli, M. L., Johnson, S. G., & Joannopoulos, J. D. (2005). Slow-light, band-edge waveguides for tunable time delays. Optics Express, 13(18), 7145. doi:10.1364/opex.13.007145Garcia, J., Sanchis, P., Martinez, A., & Marti, J. (2008). 1D periodic structures for slow-wave induced non-linearity enhancement. Optics Express, 16(5), 3146. doi:10.1364/oe.16.003146Pérez-Millán, P., Torres-Peiró, S., Cruz, J. L., & Andrés, M. V. (2008). Fabrication of chirped fiber Bragg gratings by simple combination of stretching movements. Optical Fiber Technology, 14(1), 49-53. doi:10.1016/j.yofte.2007.07.00
Tratamiento quirúrgico de la escoliosis en el síndrome de Rett: sistema de instrumentación TRANSPINE
El Síndrome de Rett es una afectación neurológica que en los estadios últimos presenta deformidades evolutivas que suelen precisar cirugía. Se han revisado en este estudio 11 pacientes con Síndrome de Rett y deformidad en columna que precisaron cirugía. Se analizaron las magnitudes de las curvas con ángulo de Cobb, alteraciones del plano sagital (cifosis y lordosis), oblicuidad pélvica pre y postoperatoria, niveles de fusión y complicaciones postoperatorias. La corrección media fue del 65%. Se realizó una fusión posterior en todos los pacientes sin incluir sacro pelvis. Los montajes se realizaron principalmente con sistema híbrido de tornillos, ganchos, pinzas y cables laminares TRANSPINE®. Las escoliosis neuromusculares, como el síndrome de Rett, que precisan corrección, pueden controlarse de forma segura y efectiva mediante artrodesis posterior con instrumentación híbrida.Rett Syndrome is a neurological impairment with a typically long C scoliosis curve that often require surgery. In this study it has been reviewed 11 patients with Rett syndrome and spine deformity. We analyzed the magnitudes of the curves with Cobb angle, sagittal plane (kyphosis and lordosis), preoperative and postoperative pelvic obliquity, fusion levels and postoperative complications. The average correction was 65%. Posterior fusion was performed in all patients excluding sacrum pelvis. The assemblies are made mainly with the hybrid system of screws, hooks, clips and cables TRANSPINE®. Neuromuscular scoliosis, such as Rett syndrome, which needs correction, can be controlled safely and effectively by posterior fusion with hybrid constructs
Flow Regimes in Fine Cohesive Powders
Granular materials exhibit several regimes of behavior: plastic, inertial, fluidized, and entrained flow, but not all materials can pass through all of these states. Our concern is with the criteria that determine the transition from one regime to another and with the boundaries to the various flow regimes that these criteria define. Experimentally we have focused on fine, cohesive powders, where the interparticle cohesive force dominates over gravitational force and where entrained air can cause moving powder to become fluidized
Reproducción asexual, sexual y vigor en semillas de caracolí Anacardium excelsum (Bertero ex Kunth) Skeels en el departamento de Sucre
The dry tropical forest in Colombia is in constant decline and deforestation of their coverage, Anacardium excelsum is a representative in this forest, but is almost threatened at the nationwide. Given this and its importance as a timber tree the objective of the research was to find the best form of reproduction, sexual or asexual, and determine the vigor and the best pre-germinative treatment to break dormancy of seeds. Seven different pre-germinative treatments and three with hormone solution for rooting cuttings were performed. Scarification with a scalpel and immersion in HCl for 5 minutes had a higher percentage of germination, most plants germinated before 4 days after being planted, and showed a growth rate between 3 and 4 cm per day in the first week. With respect to the asexual reproduction, in no of the stakes was obtained formation of roots and buds. Sexual reproduction proved to be the best method, and the pre-germinative scarification treatment with scalpel was the one with the highest percentage of germination.El bosque seco tropical en Colombia se encuentra en disminución y deforestación constante de su cobertura, Anacardium excelsum es un representante en este tipo de bosque, sin embargo se encuentra casi amenazada a nivel nacional. Teniendo en cuenta este aspecto y su importancia como especie maderable, el objetivo de la investigación fue hallar la mejor forma de reproducción, sexual o asexual, y determinar el vigor y el mejor tratamiento pre-germinativo para romper la latencia de las semillas. Se realizaron siete tratamientos pre-germinativos y tres con solución de hormona para enraizamiento de estacas. La escarificación con bisturí e inmersión en HCl por 5 minutos presentaron un mayor porcentaje de germinación, la mayor parte de las plantas germinaron antes de los 4 días de haber sido sembradas, y presentaron una tasa de crecimiento entre 3 y 4 cm por día en la primera semana. Con respecto a la reproducción asexual, en ninguna de las estacas se obtuvo formación de raíces y yemas. La reproducción sexual resultó ser el mejor método, y el tratamiento pre-germinativo de escarificación con bisturí fue el que presento mayor porcentaje de germinación
Pretensado y comportamiento mecánico del pericardio de ternera utilizado en la construcción de bioprótesis cardíacas
Este trabajo analiza las propiedades mecánicas de un tejido biológico, pericardio de bovino
empleado como biomaterial en la fabricación de bioprótesis cardíacas. Para ello se sometió
pericardio de ternera a un estrés de tracción, uniaxial, en escalones de carga, con retirada de dicha
carga tras cada escalón. Los escalones de carga fueron de aproximadamente 2,3 y 8 MPa sucesivamente,
continuándose finalmente el ensayo hasta la rotura. Se ensayaron 32 muestras, 16 tratadas
con glutaraldehído como grupo de control y 16 tratadas con cloroformo/metanol. La resistencia
media a rotura estuvo entre 19.14 MPa y 32.60 MPa sin encontrar diferencias estadísticamente
significativas en la comparación de las series ensayadas. Se estudio también el estrés remanente
tras cada escalón de carga, siendo este constante en su valor para cada ensayo. Para un valor
medio de estrés inicial de 2.14 MPa, el estrés remanente medio fue de 0.36 MPa (16.82 % del estrés
inicial) muy similar al estrés máximo de trabajo descrito para un velo valvular. La aplicación de un
estrés progresivo produce una disminución de la deformación con pérdida de la elasticidad ,pero
un comportamiento mas homogéneo del pericardio. Este hallazgo no se afectó, por la región de
pericardio de donde se obtuvo la muestra o por tratamiento químico recibido. Estos ensayos permiten,
mediante una recta de regresión Xi=f(Ymax.),conocer la deformación (Xi) que puede sufrir el
pericardio de ternera, tras un estrés de pretensado previo (Ymax.), cuando posteriormente se le
somete a un estrés.Peer Reviewe
Study of Cellular Processes in Higher Eukaryotes Using the Yeast Schizosaccharomyces pombe as a Model
Schizosaccharomyces pombe (Sz. pombe), or fission yeast, is an ascomycete unicellular fungus that has been used as a model system for studying diverse biological processes of higher eukaryotic cells, such as the cell cycle and the maintenance of cell shape, apoptosis, and ageing. Sz. pombe is a rod-shaped cell that grows by apical extension; it divides along the long axis by medial fission and septation. The fission yeast has a doubling time of 2–4 hours, it is easy and inexpensive to grow in simple culture conditions, and can be maintained in the haploid or the diploid state. Sz. pombe can be genetically manipulated using methods such as mutagenesis or gene disruption by homologous recombination. Fission yeast was defined as a micro-mammal because it shares many molecular, genetic, and biochemical features with cells of higher eukaryotes in mRNA splicing, post-translational modifications as N-glycosylation protein, cell-cycle regulation, nutrient-sensing pathways as the target of rapamycin (TOR) network, cAMP-PKA pathway, and autophagy. This chapter uses Sz. pombe as a useful model for studying important cellular processes that support life such as autophagy, apoptosis, and the ageing process. Therefore, the molecular analysis of these processes in fission yeast has the potential to generate new knowledge that could be applied to higher eukaryotes
Comportamiento a fractura de aleaciones pulvimetalúrgicas de Cu-Al-Ni con efecto memoria de forma
The use of the SeDeM diagram expert system for the formulation of Captopril SR matrix tablets by direct compression
The SeDeM Diagram Expert System has been used to study excipients, Captopril and designed formulations for their galenic characterization and to ascertain the critical points of the formula affecting product quality to obtain suitable formulations of Captopril Direct Compression SR Matrix Tablets. The application of the Sedem Diagram Expert System enables selecting excipients with in order to optimize the formula in the preformulation and formulation studies. The methodology is based on the implementation of ICH Q8, establishing the design space of the formula with the use of experiment design, using the parameters of the SeDeM Diagram Expert System as system responses
Spatial and temporal variability of discards indicators and fishery factors affecting otter-trawl fishery in the spanish Mediterranean sea
A set of diversity indices were studied from data of observers on board two Mediterranean trawlers from 2001 to 2009. These diversity indices comprise relationships between total catch, landing and discard fractions to explore the accuracy of the estimates and to analyse the series trends using different methods, such as ARIMA. The hypothesis tested was that diversity indicators give a good representation of the changes produced in impacted bottom‐trawl areas, providing a reasonable fit of the data. ARIMA models are useful because they handle time-correlated modelling and forecasting. These techniques can also reveal changes in total catch as well changes in catch composition, probably induced by changes in effort fishery, seasonal (time) fluctuations, and environmental or climatic processes. Contrasted trends were also compared with survey data by MEDITS Mediterranean trawl survey time‐series indicator
A chromosome-level genome assembly enables the identification of the follicule stimulating hormone receptor as the master sex determining gene in the flatfish Solea senegalensis
Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 SNP variants in the follicle stimulating hormone receptor (fshr) consistent with an XX / XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. Fshr displayed differential gene expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 non-synonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis.info:eu-repo/semantics/acceptedVersio
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