252 research outputs found
Sensing the turbulent large-scale motions with their wall signature
This study assesses the capability of extended proper orthogonal decomposition (EPOD) and convolutional neural networks (CNNs) to reconstruct large-scale and very-large-scale motions (LSMs and VLSMs respectively) employing wall-shear-stress measurements in wall-bounded turbulent flows. Both techniques are used to reconstruct the instantaneous LSM evolution in the flow field as a combination of proper orthogonal decomposition (POD) modes, employing a limited set of instantaneous wall-shear-stress measurements. Due to the dominance of nonlinear effects, only CNNs provide satisfying results. Being able to account for nonlinearities in the flow, CNNs are shown to perform significantly better than EPOD in terms of both instantaneous flow-field estimation and turbulent-statistics reconstruction. CNNs are able to provide a more effective reconstruction performance employing more POD modes at larger distances from the wall and employing lower wall-measurement resolutions. Furthermore, the capability of tackling nonlinear features of CNNs results in estimation capabilities that are weakly dependent on the distance from the wall.This work has been partially supported by Grant No. DPI2016-79401-R funded by the Spanish State Research Agency (SRA) and the European Regional Development Fund (ERDF). A.G. acknowledges Dr. A. SĂĄnchez for insightful discussions about CNN architecture. The authors acknowledge Dr. R. Vinuesa for insightful comments and discussions
Aberration-free ultra-thin flat lenses and axicons at telecom wavelengths based on plasmonic metasurfaces
The concept of optical phase discontinuities is applied to the design and
demonstration of aberration-free planar lenses and axicons, comprising a phased
array of ultrathin subwavelength spaced optical antennas. The lenses and
axicons consist of radial distributions of V-shaped nanoantennas that generate
respectively spherical wavefronts and non-diffracting Bessel beams at telecom
wavelengths. Simulations are also presented to show that our aberration-free
designs are applicable to high numerical aperture lenses such as flat
microscope objectives
Extra Virgin Olive Oil Contains a Phenolic Inhibitor of the Histone Demethylase LSD1/KDM1A
The lysine-specific histone demethylase 1A (LSD1) also known as lysine (K)-specific
demethylase 1A (KDM1A) is a central epigenetic regulator of metabolic reprogramming in
obesity-associated diseases, neurological disorders, and cancer. Here, we evaluated the ability
of oleacein, a biophenol secoiridoid naturally present in extra virgin olive oil (EVOO), to target
LSD1. Molecular docking and dynamic simulation approaches revealed that oleacein could target
the binding site of the LSD1 cofactor flavin adenosine dinucleotide with high affinity and at low
concentrations. At higher concentrations, oleacein was predicted to target the interaction of LSD1
with histone H3 and the LSD1 co-repressor (RCOR1/CoREST), likely disturbing the anchorage of
LSD1 to chromatin. AlphaScreen-based in vitro assays confirmed the ability of oleacein to act as
a direct inhibitor of recombinant LSD1, with an IC50 as low as 2.5 umol/L. Further, oleacein fully
suppressed the expression of the transcription factor SOX2 (SEX determining Region Y-box 2) in cancer
stem-like and induced pluripotent stem (iPS) cells, which specifically occurs under the control of an
LSD1-targeted distal enhancer. Conversely, oleacein failed to modify ectopic SOX2 overexpression
driven by a constitutive promoter. Overall, our findings provide the first evidence that EVOO contains
a naturally occurring phenolic inhibitor of LSD1, and support the use of oleacein as a template to
design new secoiridoid-based LSD1 inhibitors.Work in the Menendez laboratory is supported by the Spanish Ministry of Science and Innovation
(Grant SAF2016-80639-P, Plan Nacional de l+D+I, founded by the European Regional Development Fund, Spain)
and by an unrestricted research grant from the FundaciĂł Oncolliga Girona (Lliga catalana dâajuda al malalt de
cĂ ncer, Girona). The Spanish Ministry of Economy and Competitiveness (MINECO, Project RTI2018-096724-B-C21)
and the Generalitat Valenciana (PROMETEO/2016/006) supports work in the Encinar laborator
Characterization of Annona cherimola mill. Seed oil from Madeira Island: a possible biodiesel feedstock
The possibility of using Annona seed oil as an
added value product, namely as a source of biodiesel, is
explored. Milled Annona seeds were extracted with hexane
at room temperature (72 h) and at solvent boiling point
(6 h). Oil content was found to be 25 and 22.4% respec tively. The oil was characterized in terms of lipid compo sition (HPLCâAPCIâMS and 13C NMR), resistance to
oxidation and acidity index. FAME composition was
determined by GCâMS and five major peaks were identi fied. Production of biodiesel from Annonaâs seed oil was
achieved by base-catalyzed transesterification. Density,
viscosity, refraction coefficient, acid value, cold filter
plugging point, cloud point and oxidation stability were
measured. The iodine value and the ââapparent cetane
numberââ were calculated. Density, viscosity, acid value,
iodine value, cold filter plugging point and cloud point
were within EN14214 specifications and the calculated
ââapparent cetane numberââ was also indicative of a suitable
product.info:eu-repo/semantics/publishedVersio
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