2,442 research outputs found

    Noise reduction using wavelet cycle spinning: analysis of useful periodicities in the z-transform domain

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    Cycle spinning (CS) and a'trous algorithms are different implementations of the undecimated wavelet transform (UWT). Both algorithms can be used for UWT and even though the resulting wavelet coefficients are different, they keep a correspondence. This paper describes an analysis of the CS algorithm performed in the z-transform domain, showing the similarities and differences with the a'trous implementation. CS generates more wavelet coefficients than a'trous, but the number of significative and different coefficients is the same in both cases because of the occurrence of a periodic repetition in CS coefficients. Mathematical expressions for the relationship between CS and a'trous coefficients and for CS coefficient periodicities are provided in the z-transform domain. In some wavelet denoising applications, periodicities (present in the coefficients of the CS procedure) can also be found in the performance measure of the processed signals. In particular, in ultrasonic CS denoising applications, periodicities have been appreciated in the signal-to-noise ratio (SNR) of the ultrasonic denoised signals. These periodicities can be used to optimize the number of CS coefficients for an efficient implementation. Two examples showing the periodicities in the SNR are included. A selection of several reduced sets of CS wavelet coefficients has been utilized in the examples, and the SNRs resulting after denoising are analyzed.This work was partially supported by Spanish MCI Project DPI2011-22438 and MEC Project TIN2013-47272-C2-1-R. The translation of this paper was funded by the Universitat Politecnica de Valencia, Spain.Rodríguez-Hernández, MA.; San Emeterio, JL. (2016). Noise reduction using wavelet cycle spinning: analysis of useful periodicities in the z-transform domain. Signal, Image and Video Processing. 10(3):519-526. https://doi.org/10.1007/s11760-015-0762-8S519526103Daubechies, I.: Ten Lectures on Wavelets. 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    Preparation and characterization of non-supported microfiltration membranes from aluminosilicates

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    In the present work non-supported microfiltration ceramic membranes have been made from different aluminosilicate paste formulations. The cast green dopes were sintered at temperatures between 1100 and 1400°C. The membrane characterisation was made by scanning electron microscopy (SEM), mercury porosimetry, gas and water permeabilities and microorganisms rejection. The results indicate that an appropriate election of the size of the particles in the paste and of the final sintering temperature allows to obtain membranes with different mechanical and structural properties, with mean pore sizes within the range from 0.1 to 1 μm, that make them suitable for microfiltration.Fil: Almandoz, M.C.. Universidad Nacional de San Luis. Facultad de Ciencias Fisico Matematicas y Naturales. Departamento de Fisica. Laboratorio de Ciencias de Superficies y Medios Porosos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Marchese, Jose. Universidad de Valladolid; España. Universidad Nacional de San Luis. Facultad de Ciencias Fisico Matematicas y Naturales. Departamento de Fisica. Laboratorio de Ciencias de Superficies y Medios Porosos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Prádanos, P.. Universidad de Valladolid; EspañaFil: Palacio, L.. Universidad de Valladolid; EspañaFil: Hernández, A.. Universidad de Valladolid; Españ

    Influence of a football match on landing biomechanics and jump performance in female football players

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    This study aimed to assess the acute effect of a competitive football match on jump performance and kinematic parameters during jump landing in semiprofessional female football players. Twenty-two semiprofessional players (20 ± 3 years) underwent a drop jump task for a posterior video analysis of the landing phase. These measurements were obtained at (1) baseline, (2) after, and (3) 48 h after a competitive football match. A one-way ANOVA with repeated measures was employed to detect differences over the time. There was a main effect of time for maximal knee flexion angle during drop landing (p = 0.001). In comparison with baseline, maximal knee flexion angle was reduced immediately post-match and was still reduced 48 h after the match (63.4 ± 8.6 vs 57.0 ± 11.7 vs 48.9 ± 19.1, p ≤ 0.038). There was also a main effect of time for drop jump height (p < 0.001). Drop jump height was reduced immediately post-match and remained low 48 h after the match in comparison with baseline (27.3 ± 3.6 vs 24.5 ± 2.8 ~ 25.5 ± 3.0 cm, p ≤ 0.002). There was a main effect of time on hip flexion angle during landing (p = 0.001), but the pairwise comparison revealed that this variable was not affected immediately post-match but was lower 48 h after the match than at baseline (50.1 ± 10.1 ~ 50.8 ± 13.2 vs 38.1 ± 17.8 °, p ≤ 0.005). A competitive football match worsened jump performance and several landing biomechanical parameters in female football players, which were still decreased in comparison with baseline even 48 h after the match

    Morphology and structure of ABS membranes filled with two different activated carbons

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    Mixed matrix-composite membranes (MMCM) for gas separation are prepared and characterized in this work. Acrylonitrile-butadiene-styrene (ABS) copolymer was used for the continuum phase of the membrane filled with two different activated carbons (AC). The so-obtained membranes have been characterized by gas permeability, optical microscopy, electronic microscopy and atomic force microscopy. The membranes have different roughness on both their surfaces but are always recovered by the polymeric material. Better ABS-AC adhesion has been always reached giving high selectivity and permeability for CO2 / CH4. Such intimate contact can be attributed to the rubber properties of the butadiene-styrene chains in ABS. The morphological characteristics and the increase in both permeability and selectivity with the volume fraction of the filler are explained in terms of the properties of pure activated carbons.Fil: Marchese, Jose. Universidad Nacional de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Fisico Matematicas y Naturales. Departamento de Fisica. Laboratorio de Ciencias de Superficies y Medios Porosos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Anson, M.. Universidad Nacional de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Fisico Matematicas y Naturales. Departamento de Fisica. Laboratorio de Ciencias de Superficies y Medios Porosos; ArgentinaFil: Ochoa, Nelio Ariel. Universidad Nacional de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Fisico Matematicas y Naturales. Departamento de Fisica. Laboratorio de Ciencias de Superficies y Medios Porosos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Prádanos, P.. Universidad de Valladolid; EspañaFil: Palacio, L.. Universidad de Valladolid; EspañaFil: Hernández, A.. Universidad de Valladolid; Españ

    Towards Sustainable and Smart Cities: Replicable and KPI-Driven Evaluation Framework

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    Sustainability is pivotal in the urban transformation strategy in order to reach more resource-efficient, resilient and smarter cities. The goal of being a sustainable city should drive the decisions for city interventions, and measuring city progress is a key step for this process. There are many initiatives aiming at defining indicators and assessment procedures, but there is no convergence in the definition of terms and application methodologies, making their real implementation complex. Within mySMARTLife project (GA#731297), a KPI-driven evaluation framework has been defined with the aim of covering the multiple pillars of a smart and sustainable city (i.e., environment, energy, mobility, ICT, citizens, economy, governance) in a holistic way. This methodology also defines the concepts and terms to guide urban planners and/or experts at the time of implementing the framework for any specific city. The evaluation framework has been deployed in the cities of Nantes, Hamburg and Helsinki, and some lessons have been learned, such as the necessity of providing a definition of measurement boundary to avoid biased interpretations. Due to a co-creation strategy, the main issues from the cities have been taken into consideration in order to increase the replicability of the results.The work presented in this paper is the result of the EU-funded project mySMARTLife, under the H2020 programme with grant agreement no. 731297

    Perfiles de personalidad y síndromes clínicos en personas sin hogar

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    Abstract: Personality profiles and clinical syndromes in the homeless . The aims of this study were to analyze in a sample of homeless persons the prevalence of clinical personality patterns and clinical syndromes, to examine the relationship between the two, and to identify common personality profiles. Participants were 144 subjects, 35 women and 109 men, with a mean age of 42 years, all in a situation of chronic social exclusion, 67% were homeless for more than a year, and 33% more than three years. During the evaluation period they resided in a shelter for the homeless. Results showed that clinical personality patterns and clinical syndromes with higher prevalence, according to Millon’s model, were respectively: depressive, narcissistic and paranoid, as well as anxiety, drug dependence and thought disorder. In addition, cluster analysis classified subjects into two groups "narcissistic-adaptive" and "depressive-paranoid". These results suggest that treatment and health resources should be adapted based on psychiatric deterioration, considering the homeless as a heterogeneous group with different psychosocial needs.Resumen: Los objetivos de este trabajo fueron: analizar la prevalencia de patrones clínicos de personalidad y de síndromes clínicos, examinar la relación entre ambos e identificar perfiles de personalidad comunes en una muestra de personas sin hogar. Los participantes fueron 144 sujetos, 35 mujeres y 109 hombres, con una media de edad de 42 años, todos ellos en una situación de exclusión social crónica, el 67% llevaba sin hogar un periodo de tiempo superior a un año, y el 33% más de tres años. Durante el periodo de evaluación residían en un albergue para personas sin hogar. Los resultados mostraron que los patrones clínicos de personalidad y los síndromes clínicos de mayor prevalencia, de acuerdo al modelo de Millon, fueron: depresivo, narcisista y paranoide, así como la ansiedad, la drogodependencia y el trastorno del pensamiento, respectivamente. Además, el análisis de cluster clasificó a los sujetos en dos grupos “narcisista-adaptativo” y “depresivo-paranoide”. Estos resultados sugieren que se deben adaptar los tratamientos y recursos sanitarios en función del deterioro psiquiátrico, considerando a las personas sin hogar como un colectivo heterogéneo con necesidades psicosociales diferentes

    Triple-Negative Breast Cancer: A Review of Conventional and Advanced Therapeutic Strategies

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    Triple-negative breast cancer (TNBC) cells are deficient in estrogen, progesterone and ERBB2 receptor expression, presenting a particularly challenging therapeutic target due to their highly invasive nature and relatively low response to therapeutics. There is an absence of specific treatment strategies for this tumor subgroup, and hence TNBC is managed with conventional therapeutics, often leading to systemic relapse. In terms of histology and transcription profile these cancers have similarities to BRCA-1-linked breast cancers, and it is hypothesized that BRCA1 pathway is non-functional in this type of breast cancer. In this review article, we discuss the different receptors expressed by TNBC as well as the diversity of different signaling pathways targeted by TNBC therapeutics, for example, Notch, Hedgehog, Wnt/b-Catenin as well as TGF-beta signaling pathways. Additionally, many epidermal growth factor receptor (EGFR), poly (ADP-ribose) polymerase (PARP) and mammalian target of rapamycin (mTOR) inhibitors effectively inhibit the TNBCs, but they face challenges of either resistance to drugs or relapse. The resistance of TNBC to conventional therapeutic agents has helped in the advancement of advanced TNBC therapeutic approaches including hyperthermia, photodynamic therapy, as well as nanomedicine-based targeted therapeutics of drugs, miRNA, siRNA, and aptamers, which will also be discussed. Artificial intelligence is another tool that is presented to enhance the diagnosis of TNBC

    Carbon remineralization by small mesopelagic and bathypelagic Stomiiforms in the Northeast Atlantic Ocean

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    The organic carbon resulting from photosynthesis in the upper ocean is transferred downward through the passive sinking of organic particles, physical mixing of particulate and dissolved organic carbon as well as active flux transported by zooplanktonic and micronektonic migrants. Several meso- and bathypelagic organisms feed in shallower layers during the nighttime and respire, defecate, excrete and die at depth. Recent studies suggest that migrant micronekton transport similar amounts of carbon to migrant zooplankton. However, there is scarce information about biomass and carbon flux by non-migratory species in the mesopelagic and bathypelagic zones. The non-migratory bristlemouth fishes (Cyclothone spp.) and partial migrator (A. hemigymnus) remineralise organic carbon at depth, and knowledge about this process by this fauna is lacking despite them having been referred to as the most abundant vertebrates on Earth. Here we show the vertical distribution of biomass and respiration of non-migratory mesopelagic fishes, during day and night, using the enzymatic activity of the electron transfer system (ETS) as a proxy for respiration rates. The study is focused on five Cyclothone species (C. braueri, C. pseudopallida, C. pallida, C. livida and C. microdon) and Argyropelecus hemigymnus. The samples were taken on a transect from the oceanic upwelling off Northwest Africa (20° N, 20° W) to the south of Iceland (60° N, 20° W). Cyclothone spp. showed, by far, the largest biomass (126.90 ± 86.20 mg C·m⁻²) compared to A. hemigymnus (0.54 ± 0.44 mg C·m⁻²). The highest concentrations of Cyclothone spp. in the water column were observed between 400 and 600 m and from 1000 to 1500 m depths, both during day and night. For the different species analysed, ETS activity did not show significant differences between diurnal and nocturnal periods. The total average specific respiration of Cyclothone spp. (0.02 ± 0.01 d⁻¹) was lower than that observed for A. hemigymnus (0.05±0.02 d⁻¹). The average carbon respiration of Cyclothone spp. was 2.22 ± 0.81 mg C·m⁻²·d⁻¹, while it was much lower for A. hemigymnus (0.04 ± 0.03 mg C·m⁻²·d⁻¹). The respiration of Cyclothone spp. was lower in the bathypelagic than in the mesopelagic zone (0.84 ± 0.48 vs 1.36 ± 1.01 mg C·m⁻²·d⁻¹, respectively). These results, to our knowledge, provide the first account of remineralisation by this community in the meso and bathypelagic zones of the ocean.En prens

    Dietary composition and feeding strategy of Leptodactylus fuscus (Anura: Leptodactylidae) from a suburban area of the Caribbean Region of Colombia

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    The use of trophic resources by anurans may be influenced by sexual dimorphism, ontogenetic variation and resources available in the environment. However, most studies on anuran feeding behavior lack of environmental prey availability data. In this study, the dietary composition and the feeding strategy of Leptodactylus fuscus were evaluated considering the availability of potential prey in a sub-urban area of the Colombian Caribbean Region. Additionally, differences in diet composition between adult and juvenile’ frogs were assessed. Prey items were obtained through forced regurgitation technique and prey availability was assessed using pitfall traps. The importance of each prey category and prey selectivity were evaluated through a relative importance index and a food selection index, respectively. Twenty-four stomachs were analyzed, being Hymenoptera the most important prey category and the most abundant resource in the environment. The population of L. fuscus showed a low prey selectivity and prey size was associated with frog’s body size. However, there was no variation in numeric and volumetric dietary composition related to ontogeny. Considering the relationship between the diet and prey availability, our results evidenced L. fuscus exhibits a generalist and opportunistic feeding behavior, which highlight the importance of including information on prey availability to better understand the anurans dietary behavior.Asociación Herpetológica Argentin
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