In this research, global optimization algorithms were applied to solve the inverse artificial neural network (ANNi) for obtaining the best inputs values of an absorption heat transformer with energy ...recycling (AHTER) and improving its performance. The ANNi was obtained by inverting an artificial neural network (ANN) which architecture was 16 input variables, 3 neurons in the hidden layer and 1 output variable. The ANNi’s aim was optimizing 1, 2, 3, and up to 4 manipulated input variables, as well as calculating the other 12 input variables not manipulated in the system (AHTER) considering a coefficient of performance (COP) desired. The Cuckoo Search (CS), Particle Swarm Optimization (PSO), Genetic Algorithm (GA) and Simulated Annealing (SA) algorithms were used to find the optimal inputs. The results showed that the four algorithms used (ANNi-CS, ANNi-PSO, ANNi-GA, and ANNi-SA) satisfactorily optimize of 1 up to 16 inputs of the ANNi. However, the algorithms of ANNi-CS and ANNi-SA were slightly faster with acceptable accuracy. Additionally, they were carried out two analyses using different COPs values. These analyses showed that both algorithms optimize the AHTER’s inputs for different COP, as well as R>0.988 were obtained with the COP experimental data against COP obtained data by both ANNi models.
•4 global optimization algorithms were applied to solve the ANNi.•A multi-variable function was solved by CS, PSO, GA and SA.•1 to up 4 inputs variables were optimized to improve the COP of an AHTER.•1 to 16 inputs variables were obtained with ANNi-CS, ANNi-PSO, ANNi-GA, and ANNi-SA.•COP was maximized applying ANNi-CS and ANNi-SA considering the limits of the device.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper we aim to validate a methodology designed to obtain Hα emission line fluxes from J-PLUS photometric data. J-PLUS is a multi narrow-band filter survey carried out with the 2 deg2 field ...of view T80Cam camera, mounted on the JAST/T80 telescope in the OAJ, Teruel, Spain. The information of the twelve J-PLUS bands, including the J0660 narrow-band filter located at rest-frame Hα, is used over the first 42 deg2 observed to retrieve de-reddened and NII decontaminated Hα emission line fluxes of 46 star-forming regions with previous SDSS and/or CALIFA spectroscopic information. The agreement between the J-PLUS Hα fluxes and those obtained with spectroscopic data is remarkable, finding a median comparison ratio with a scatter of R = F H α J − PLUS / F H α spec = 1.05 ± 0.25 $ \mathcal{R}\,{=}\,F^{\mathrm{J-PLUS}}_{\mathrm{H\alpha}}/F^{\mathrm{spec}}_{\mathrm{H\alpha}}\,{=}\,1.05\,{\pm}\,0.25 $ . This demonstrates that it is possible to retrieve reliable Hα emission line fluxes from J-PLUS photometric data. With an expected area of thousands of square degrees upon completion, the J-PLUS dataset will allow the study of several star formation science cases in the nearby universe, as the spatially resolved star formation rate of nearby galaxies at z ≤ 0.015, and how it is influenced by the environment, morphology, stellar mass, and nuclear activity. As an illustrative example, the close pair of interacting galaxies NGC 3994 and NGC 3995 is analysed, finding an enhancement of the star formation rate not only in the centre, but also in outer parts of the disk of NGC 3994.
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ABSTRACT
Using two cultivars of Pisum sativum L. with different sensitivity to NaCl, the effect of long‐term (15 d) NaCl (70 m
M) treatments on the activity and expression of the foliar ...ascorbate–glutathione cycle enzymes, superoxide dismutase isozymes and their mRNAs was evaluated and related to their ascorbate and glutathione contents. High‐speed supernatant (soluble) fractions, enriched for cytosolic components of the antioxidant system, were used. In this fraction from the NaCl‐tolerant variety (cv Granada), the activities of ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR), Mn‐superoxide dismutase (Mn‐SOD) and dehydroascorbate reductase (DHAR) increased, while CuZn‐SOD activity remained constant. In the NaCl‐sensitive plants (cv Challis), salinity did not produce significant changes in APX, MDHAR and GR activities. Only DHAR activity was induced in cv Challis, whereas soluble CuZn‐SOD activity decreased by about 35%. Total ascorbate and glutathione contents decreased in both cultivars, but the decline was greater in NaCl‐sensitive plants. This difference between the two cultivars was more pronounced when the transcript levels of some these enzymes were examined. Transcript levels for mitochondrial Mn‐SOD, chloroplastic CuZn‐SOD and phospholipid hydroperoxide glutathione peroxidase (PHGPX), cytosolic GR and APX were strongly induced in the NaCl‐tolerant variety but not in the NaCl‐sensitive variety. These data strongly suggest that induction of antioxidant defences is at least one component of the tolerance mechanism of peas to long‐term salt‐stress.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Aims.
We estimated the spectral evolution of white dwarfs with effective temperature using the Javalambre Photometric Local Universe Survey (J-PLUS) second data release (DR2), which provides 12 ...photometric optical passbands over 2176 deg
2
.
Methods.
We analyzed 5926 white dwarfs with
r
≤ 19.5 mag in common between a white dwarf catalog defined from
Gaia
EDR3 and J-PLUS DR2. We performed a Bayesian analysis by comparing the observed J-PLUS photometry with theoretical models of hydrogen- and helium-dominated atmospheres. We estimated the probability distribution functions for effective temperature (
T
eff
), surface gravity, parallax, and composition; and the probability of having a H-dominated atmosphere (
p
H
) for each source. We applied a prior in parallax, using
Gaia
EDR3 measurements as a reference, and derived a self-consistent prior for the atmospheric composition as a function of
T
eff
.
Results.
We described the fraction of white dwarfs with a He-dominated atmosphere (
f
He
) with a linear function of the effective temperature at 5000 <
T
eff
< 30 000 K. We find
f
He
= 0.24 ± 0.01 at
T
eff
= 10 000 K, a change rate along the cooling sequence of 0.14 ± 0.02 per 10 kK, and a minimum He-dominated fraction of 0.08 ± 0.02 at the high-temperature end. We tested the obtained
p
H
by comparison with spectroscopic classifications, finding that it is reliable. We estimated the mass distribution for the 351 sources with distance
d
< 100 pc, mass
M
> 0.45
M
⊙
, and
T
eff
> 6000 K. The result for H-dominated white dwarfs agrees with previous studies, with a dominant
M
= 0.59
M
⊙
peak and the presence of an excess at
M
∼ 0.8
M
⊙
. This high-mass excess is absent in the He-dominated distribution, which presents a single peak.
Conclusions.
The J-PLUS optical data provide a reliable statistical classification of white dwarfs into H- and He-dominated atmospheres. We find a 21 ± 3% increase in the fraction of He-dominated white dwarfs from
T
eff
= 20 000 K to
T
eff
= 5000 K.
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•Role of laccase from Streptomyces ipomoeae on wheat straw lignin was investigated.•Analytical pyrolysis discerned ligninolytic activity from wild and mutant strains.•Laccase is found a key enzyme in ...S. ipomoeae (SilA) for lignin solubilisation in solid state fermentation.
Streptomycetes are actually considered one of the main groups of ligninolytic microoganisms producing a lignin-carbohydate complex named APPL (acid precipitable polymeric lignin) when growing on lignocellulosic materials. Although in these conditions the production of hemicellulolytic and oxidative extracellular enzymes were reported the specific role of laccases in lignin degradation is poorly understood. SilA, a thermostable salt-resistant and pH-versatile laccase produced by Streptomyces ipomoeae CECT 3341 was recently discovered and their particular characteristics make attractive to deep in its knowledge for biotechnological and environmental purposes. Pyrolysis/GC–MS was used to analyse the behaviour of the laccase-producing strain (SilA strain) and a laccase-negative mutant (SilA− strain) when growing on wheat straw in solid-state fermentation (SSF). Quantitative yields of APPL and the relative abundance of lignin-derived compounds were much higher for SilA strain than for SilA− showing a higher solubilizing activity of S. ipomoeae wild-type on lignocellulosic residues. Nonetheless the patterns of lignin derived compounds found in the APPL pyrograms were similar for both strains and distinct from the control showing a shortening of lignin propyl side-chains. Our results demonstrate that SilA laccase is a key enzyme in the lignin solubilization by S. ipomoeae and also points to the involvement of other oxidative enzymatic activities distinct to laccase in this process.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In this work, an experimental fault tolerant control (FTC) implementation is presented. The FTC is based on a multi-input multi-output (MIMO) model predictive control (MPC). The aim of the FTC is to ...keep on operating a double-pipe counter-current heat exchanger even if the main actuator of the heat exchanger is stuck open. To develop the FTC, an adaptive observer was implemented in order to design a fault detection and isolation (FDI) system. In the FDI system, the cold and hot water flow rate estimations by the adaptive observer are compared to the control signals provided by the MPC. The results of the implementation of the FTC using a MIMO model predictive control were compared to the results obtained in a previous work which was developed using model-following control.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Context. Ultracool dwarfs are objects with spectral types equal to or later than M7. Most of them have been discovered using wide-field imaging surveys. The Virtual Observatory has proven to be very ...useful for efficiently exploiting these astronomical resources. Aims. We aim to validate a Virtual Observatory methodology designed to discover and characterise ultracool dwarfs in the J-PLUS photometric survey. J-PLUS is a multiband survey carried out with the wide-angle T80Cam optical camera mounted on the 0.83 m telescope JAST/T80 in the Observatorio Astrofísico de Javalambre. We make use of the Internal Data Release covering 528 deg2. Methods. We complemented J-PLUS photometry with other catalogues in the optical and infrared using VOSA, a Virtual Observatory tool that estimates physical parameters from the spectral energy distribution fitting to collections of theoretical models. Objects identified as ultracool dwarfs were distinguished from background M giants and highly reddened stars using parallaxes and proper motions from Gaia DR2. Results. We identify 559 ultracool dwarfs, ranging from i = 16.2 mag to i = 22.4 mag, of which 187 are candidate ultracool dwarfs not previously reported in the literature. This represents an increase in the number of known ultracool dwarfs of about 50% in the region of the sky we studied, particularly at the faint end of our sensitivity, which is interesting as reference for future wide and deep surveys such as Euclid. Three candidates are interesting targets for exoplanet surveys because of their proximity (distances less than 40 pc). We also analysed the kinematics of ultracool dwarfs in our catalogue and found evidence that it is consistent with a Galactic thin-disc population, except for six objects that might be members of the thick disc. Conclusion. The results we obtained validate the proposed methodology, which will be used in future J-PLUS and J-PAS releases. Considering the region of the sky covered by the Internal Data Release used in this work, we estimate that 3000–3500 new ultracool dwarfs will be discovered at the end of the J-PLUS project.
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ABSTRACT
Chemical abundance determinations in Low-Ionization Nuclear Emission-line Regions (LINERs) are especially complex and uncertain because the nature of the ionizing source of this kind of ...object is unknown. In this work, we study the oxygen abundance in relation to the hydrogen abundance (O/H) of the gas phase of the UGC 4805 LINER nucleus. Optical spectroscopic data from the Mapping Nearby Galaxies survey was employed to derive the O/H abundance of the UGC 4805 nucleus based on the extrapolation of the disc abundance gradient, on calibrations between O/H abundance and strong emission-lines for active galactic nuclei (AGNs) as well as on photoionization models built with the Cloudy code, assuming gas accretion into a black hole (AGN) and post-asymptotic giant branch (p-AGB) stars with different effective temperatures. We found that abundance gradient extrapolations, AGN calibrations, AGN, and p-AGB photoionization models produce similar O/H values for the UGC 4805 nucleus and similar ionization parameter values. The study demonstrated that the methods used to estimate the O/H abundance using nuclear emission-line ratios produce reliable results, which are in agreement with the O/H values obtained from the independent method of galactic metallicity gradient extrapolation. Finally, the results from the WHAN diagram combined with the fact that the high excitation level of the gas has to be maintained at kpc scales, we suggest that the main ionizing source of the UGC 4805 nucleus probably has a stellar origin rather than an AGN.
Integrated Ocean Drilling Program (IODP) Expedition 339 cored multiple sites in the Gulf of Cadiz in order to study contourite deposition resulting from Mediterranean Outflow water (MOW). One Hole, ...U1387C, was cored to a depth of 865.85m below seafloor (mbsf) with the goal of recovering the latest Miocene to Pliocene transition in order to evaluate the history of MOW immediately after the end of the Messinian Salinity Crisis. To understand this history, an accurate age model for the succession is needed, but is challenging to construct, because the Miocene–Pliocene boundary is not marked by a clear biostratigraphic event in the Atlantic and coring gaps occur within the recovered stratigraphic record. These limitations are overcome by combining a variety of chronostratigraphic datasets to construct an age-model that fits the currently available age indicators and demonstrates that coring in Hole U1387C did indeed recover the Miocene–Pliocene boundary at about 826mbsf. This boundary is associated with a distinct and abrupt change in depositional environment. During the latest Messinian, hemipelagic sediments exhibiting precession-induced climate variability were deposited. These are overlain by Pliocene sediments deposited at a much higher sedimentation rate, with much higher and more variable XRF core scanning Zr/Al ratios than the underlying sediment, and that show evidence of winnowing, particle sorting and increasing grain size, which we interpret to be related to the increasing flow of MOW. Pliocene sedimentary cyclicity is clearly visible in both the benthic δ18O record and the Zr/Al data and is probably also precessionally controlled. Two contouritic bigradational sandy-beds are revealed above the third sedimentary cycle of the Pliocene. On the basis of these results, we conclude that sedimentation associated with weak Mediterranean–Atlantic exchange, began in the Gulf of Cadiz virtually at or shortly after the Miocene–Pliocene boundary.
•Stratigraphic framework over the Miocene–Pliocene boundary at IODP Site U1387•Abrupt sedimentary changes over the Miocene–Pliocene boundary•Clear hints for onset of Mediterranean Outflow after the Messinian salinity crisis•Evidence of bottom water currents in contouritic sedimentation and elevated Zr/Al•Quiet, hemipelagic sediment deposition during the Messinian in the Gulf of Cadiz
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Abstract
The durability of transcatheter heart valves and long-term clinical outcomes are unknown. The aim of this study was to evaluate clinical and hemodynamic outcomes 10 years after ...Transcatheter Aortic Valve Implantation (TAVI).
Methods
Between April 2008 and December 2011, 230 patients underwent TAVI for the treatment of severe symptomatic aortic stenosis with the auto-expandable prosthesis.
Results
The mean age, logistic EuroSCORE and STS score were 79.3±6.4 years, 19.8±13% and 6.8±5% respectively. Mean aortic valve gradient decreased from 49.8±15 mm Hg to 8.6±3.8 mmHg after TAVI, to 11.1±9 mm Hg at 5 years, and 25.7±12 mmHg at 7 years (p for post-TAVI trend 0.03). Mean aortic valve area increased from 0.63±0.16 cm2 to 1.57±0.3cm2 after TAVI to 1.48±0.2 at 5 years and 0.87±0.3 cm2 at 7 years (p for post-TAVI trend 0.01). Mean left ventricular ejection fraction increased from 61.1±15% to 65.5±11% after TAVI, to 58.2±17% at 5 years and 57.2±8% at 7 years (p for post-TAVI trend 0.001).
The total mortality after a mean of 53±34 months was 73% and 34.4% was cardiovascular mortality. Survival rates at 1 to 10 years were at 86%, 75.4%, 64.9%, 59.6%, 52.6%, 33.1%, 24.9%, 20.7%, 10.4% and 10.4% respectively. Only 4 patients had severe prosthetic valve dysfunction (severe stenosis and moderate-severe transvalvular regurgitation). Median survival time after TAVI was 6 years (95% confidence interval CI: 5.89 to 6.28), and the risk of death was significantly increased in patients with frailty (adjusted hazard ratio HR: 1.874; 95% CI: 1.028 to 3.418), p=0.040, Charlson index HR=1.212 (95% CI: 1.094–1.341), p<0.001, and age HR=1.03; (95% CI: 1.001–1.062), p=0.049.
Conclusions
In our center, the transcatheter aortic valve implantation in patients at high surgical risk, presented favourable clinical outcomes and hemodynamic performance after ten years of follow-up.
Funding Acknowledgement
Type of funding sources: None.
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