428 research outputs found
BCN20000: dermoscopic lesions in the wild
This article summarizes the BCN20000 dataset, composed of 19424 dermoscopic images of skin lesions captured from 2010 to 2016 in the facilities of the Hospital Clínic in Barcelona. With this dataset, we aim to study the problem of unconstrained classification of dermoscopic images of skin cancer, including lesions found in hard-to-diagnose locations (nails and mucosa), large lesions which do not fit in the aperture of the dermoscopy device, and hypo-pigmented lesions. The BCN20000 will be provided to the participants of the ISIC Challenge 2019 [8], where they will be asked to train algorithms to classify dermoscopic images of skin cancer automatically.Peer ReviewedPreprin
Antioxidant starch films containing sunflower hull extracts
[EN] This study exploits sunflower hulls that are by-product from food industry for the extraction of valuable antioxidant compounds that can be used to produce antioxidant food packaging material based on starch. Fast and easy methanolic extraction of milled hulls resulted in an antioxidant extract with 137 mg GAE/100 g hulls and an antioxidant activity against DPPH* with an EC50 value of 73.5 mg raw hull material/ mg DPPH* and chlorogenic acid as main active compound. Already low amounts of extracts (1-6%) were sufficient to produce compression molded starch-glycerol films with antioxidant capacity without the loss of barrier properties. Films with the highest content of antioxidant extract showed the highest antioxidant activity and the lowest oxygen and water vapor permeability. These films were tough but less stretchable. A potential industrial use of these starch films could be in antioxidant packaging as a very thin layer in multilayer food packaging as oxygen barrier and antioxidant capacity.This work was supported by the Swedish Research Council Formas [2015-00550] and by the project AGL2016-76699-R from Spanish Ministerio de Educacion y Ciencia. The authors would like to acknowledge Grefusa (Alzira, Spain) for the donated sunflower hull waste.Menzel, C.; González Martínez, MC.; Chiralt, A.; Vilaplana, F. (2019). Antioxidant starch films containing sunflower hull extracts. Carbohydrate Polymers. 214:142-151. https://doi.org/10.1016/j.carbpol.2019.03.022S14215121
Optimal Filling of Shapes
We present filling as a type of spatial subdivision problem similar to
covering and packing. Filling addresses the optimal placement of overlapping
objects lying entirely inside an arbitrary shape so as to cover the most
interior volume. In n-dimensional space, if the objects are polydisperse
n-balls, we show that solutions correspond to sets of maximal n-balls. For
polygons, we provide a heuristic for finding solutions of maximal discs. We
consider the properties of ideal distributions of N discs as N approaches
infinity. We note an analogy with energy landscapes.Comment: 5 page
Accumulation of Flavonols over Hydroxycinnamic Acids Favors Oxidative Damage Protection under Abiotic Stress
Efficient detoxification of reactive oxygen species (ROS) is thought to play a key role in enhancing the tolerance of plants to abiotic stresses. Although multiple pathways, enzymes, and antioxidants are present in plants, their exact roles during different stress responses remain unclear. Here, we report on the characterization of the different antioxidant mechanisms of tomato plants subjected to heat stress, salinity stress, or a combination of both stresses. All the treatments applied induced an increase of oxidative stress, with the salinity treatment being the most aggressive, resulting in plants with the lowest biomass, and the highest levels of H2O2 accumulation, lipid peroxidation, and protein oxidation. However, the results obtained from the transcript expression study and enzymatic activities related to the ascorbate-glutathione pathway did not fully explain the differences in the oxidative damage observed between salinity and the combination of salinity and heat. An exhaustive metabolomics study revealed the differential accumulation of phenolic compounds depending on the type of abiotic stress applied. An analysis at gene and enzyme levels of the phenylpropanoid metabolism concluded that under conditions where flavonols accumulated to a greater degree as compared to hydroxycinnamic acids, the oxidative damage was lower, highlighting the importance of flavonols as powerful antioxidants, and their role in abiotic stress tolerance.This work was supported by the Ministry of Economy and Competitiveness from Spain (GrantNo. AGL2015-66033-R), and Seneca Foundation from Region of Murcia, Spain (Grant no.15288/ PI/10).Peer reviewedPeer Reviewe
Comparison of UV irradiances from Aura/Ozone Monitoring Instrument (OMI) with Brewer measurements at El Arenosillo (Spain) – Part 2: Analysis of site aerosol influence
Several validation studies have shown a notable overestimation of the clear
sky ultraviolet (UV) irradiance at the Earth's surface derived from
satellite sensors such as the Total Ozone Mapping Spectrometer (TOMS) and
the Ozone Monitoring Instrument (OMI) with respect to ground-based UV data
at many locations. Most of this positive bias is attributed to boundary
layer aerosol absorption that is not accounted for in the TOMS/OMI
operational UV algorithm. Therefore, the main objective of this study is to
analyse the aerosol effect on the bias between OMI erythemal UV irradiance
(UVER) and spectral UV (305 nm, 310 nm and 324 nm) surface irradiances and
ground-based Brewer spectroradiometer measurements from October 2004 to
December 2008 at El Arenosillo station (37.1° N, 6.7° W,
20 m a.s.l.), with meteorological conditions representative of the South-West of
Spain.
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The effects of other factors as clouds, ozone and the solar elevation over
this intercomparison were analysed in detail in a companion paper (Antón
et al., 2010). In that paper the aerosol effects were studied making only a
rough evaluation based on aerosol optical depth (AOD) information at 440 nm
wavelength (visible range) without applying any correction. We have used the
precise information given by single scattering albedo (SSA) from AERONET for
the determination of absorbing aerosols which has allowed the correction of
the OMI UV data.
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An aerosol correction expression was applied to the OMI operational UV data
using two approaches to estimate the UV absorption aerosol optical depth,
AAOD. The first approach was based on an assumption of constant SSA value of
0.91. This approach reduces the OMI UVER bias against the reference Brewer
data from 13.4% to 8.4%. Second approach uses daily AERONET SSA values
reducing the bias only to 11.6%. Therefore we have obtained a 37% and
12% of improvement respectively. For the spectral irradiance at 324 nm,
the OMI bias is reduced from 10.5% to 6.98% for constant SSA and to
9.03% for variable SSA. Similar results were obtained for spectral
irradiances at 305 nm, and 310 nm.
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Contrary to what was expected, the constant SSA approach has a greater bias
reduction than variable SSA, but this is a reasonable result according to
the discussion about the reliability of SSA values. Our results reflect the
level of accuracy that may be reached at the present time in this type of
comparison, which may be considered as satisfactory taking into account the
remaining dependence on other factors. Nevertheless, improvements must be
accomplished to determine reliable absorbing aerosol properties, which
appear as a limiting factor for improving OMI retrievals
Adherencia al tratamiento. Una revisión desde la perspectiva farmacéutica
El incumplimiento terapéutico constituye un importante problema asistencial que puede afectar a la salud de los pacientes. Es una de las posibles causas del fracaso de los tratamientos, afecta seriamente a la calidad de vida y genera importantes costes para el sistema de salud. Por estos motivos, el conocimiento de las tasas de incumplimiento resulta de gran interés sanitario. Así, para la planificación de intervenciones efectivas es necesaria la mejora de los instrumentos de medida del comportamiento en la adherencia terapéutica, así como el estudio de los factores relacionados con un apropiado cumplimiento, individual y comunitario. De acuerdo con la revisión realizada, y de forma general, se estima que un 40% de los pacientes no cumple con las recomendaciones terapéuticas. En el caso de las enfermedades agudas, la tasa de incumplimiento llega al 20%, mientras que en las enfermedades crónicas alcanza el 45%. Los principales factores que influyen en la adherencia terapéutica están relacionados con el propio paciente (creencias y motivaciones, edad o estatus socioeconómico), el tipo de enfermedad, el tratamiento propuesto para afrontarla y el propio sistema de asistencia sanitaria. El presente artículo ofrece una visión actualizada de la adherencia terapéutica, con una revisión de los diferentes métodos de medida utilizados, y se identifican los factores relacionados con ella y las principales intervenciones de mejora, incluidas las llevadas a cabo por el profesional de farmacia
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