92 research outputs found
Validation of the procedure: Quantification of the degradation index of Photovoltaic Grid Connection Systems
The results obtained from the validation of the procedure ‟Quantification of the degradation index of Photovoltaic Grid Connection Systems” are presented, using statistical parameters, which corroborate its accuracy, achieving a coefficient of determination of 0.9896, a percentage of the root of the mean square of the error RMSPE = 1.498% and a percentage of the mean absolute error MAPE = 1.15%, evidencing the precision of the procedure
Fault Diagnostic Methodology for Grid-Connected Photovoltaic Systems
This research focuses on the design of a fault diagnosis methodology to contribute to the improvement of efficiency, maintainability and availability indicators of Grid-Connected Photovoltaic Systems. To achieve this, we start from the study of the mathematical model of the photovoltaic generator, then, a procedure is performed to quantify the operational losses of the photovoltaic generator and adjust the mathematical model of this to the real conditions of the system, through a polynomial adjustment. A real system of nominal power 7.5 kWp installed in the Solar Energy Research Center of the province of Santiago de Cuba is used to evaluate the proposed methodology. Based on the results obtained, the proposed approach is validated to demonstrate that it successfully supervises the system. The methodology was able to detect and identify 100% of the simulated failures and the tests carried out had a maximum false alarm rate of 0.22%, evidencing its capacity
Procedure for the quantification of the degradation index of Photovoltaic Generators
A procedure is presented for the quantification of the degradation index of Photovoltaic Generators, based on the quantification of the operational losses inherent in the system, which allows maintaining the nominal operating conditions and by the warranty terms of the photovoltaic generator. A photovoltaic generator connected to the network with a nominal power of 7.5 kWp, installed in the Solar Energy Research Center of Santiago de Cuba, is used to evaluate and validate the procedure. The starting point is the mathematical model of the photovoltaic generator, then the operational losses of the photovoltaic generator are quantified and the mathematical model is adjusted to real conditions, through a polynomial adjustment. The results obtained show that the photovoltaic generator presents deviations in terms of the nominal power generation, because the operational losses are 7% with respect to the values given by the manufacturer
Status assessment of the Critically Endangered Azores Bullfinch Pyrrhula murina
13 páginas, 4 figuras, 1 tabla.The Azores Bullfinch is endemic to the island of São Miguel (Azores, Portugal). Its status was uplisted to Critically Endangered in 2005 on the basis of an extremely small and declining population that was considered to be restricted to a very small mountain range (43 km2), in a single location, within which the spread of invasive plants constituted a threat to habitat quality. Nevertheless, information was mostly inferred, or the product of, non-systematic studies. In order to carry out a complete assessment of the conservation status we analysed: (i) population trend, calculated from annual monitoring 1991–2008, (ii) population size, and (iii) range size, obtaining estimates in a single morning study in 2008 involving the simultaneous participation of 48 observers. Contrary to previous inferences, the population is no longer decreasing, although quality of laurel forest habitat continues to decline due to the persistent threat of invasive species. Population size (mean ± SE) was estimated at 1,064 ± 304 individuals using distance sampling methods, although the estimate was very sensitive to the survey method used. Range size estimates (extent of occurrence and area of occupancy) were 144 km2 and 83 km2 respectively. Given the present information, we propose the downlisting of Azores Bullfinch to Endangered on the IUCN Red List.Este trabajo fue parte del programa "Azores Bullfinch monitoring" incluído en el proyecto de la Comisión Europea, LIFE NAT/P/000013 “Recovery of Azores Bullfinch’s habitat in the Special Protection Area of Pico da Vara / Ribeira do Guilherme”.Peer reviewe
Magnesium accumulation upon cyclin M4 silencing activates microsomal triglyceride transfer protein improving NASH
Background & Aims: Perturbations of intracellular magnesium (Mg) homeostasis have implications for cell physiology. The cyclin M family, CNNM, perform key functions in the transport of Mg across cell membranes. Herein, we aimed to elucidate the role of CNNM4 in the development of non-alcoholic steatohepatitis (NASH). Methods: Serum Mg levels and hepatic CNNM4 expression were characterised in clinical samples. Primary hepatocytes were cultured under methionine and choline deprivation. A 0.1% methionine and choline-deficient diet, or a choline-deficient high-fat diet were used to induce NASH in our in vivo rodent models. Cnnm4 was silenced using siRNA, in vitro with DharmaFECT and in vivo with Invivofectamine® or conjugated to N-acetylgalactosamine. Results: Patients with NASH showed hepatic CNNM4 overexpression and dysregulated Mg levels in the serum. Cnnm4 silencing ameliorated hepatic lipid accumulation, inflammation and fibrosis in the rodent NASH models. Mechanistically, CNNM4 knockdown in hepatocytes induced cellular Mg accumulation, reduced endoplasmic reticulum stress, and increased microsomal triglyceride transfer activity, which promoted hepatic lipid clearance by increasing the secretion of VLDLs. Conclusions: CNNM4 is overexpressed in patients with NASH and is responsible for dysregulated Mg transport. Hepatic CNNM4 is a promising therapeutic target for the treatment of NASH. Lay summary: Cyclin M4 (CNNM4) is overexpressed in non-alcoholic steatohepatitis (NASH) and promotes the export of magnesium from the liver. The liver-specific silencing of Cnnm4 ameliorates NASH by reducing endoplasmic reticulum stress and promoting the activity of microsomal triglyceride transfer protein.Ministerio de Ciencia e Innovación, Programa Retos-Colaboración
RTC2019-007125-1 (for JS and MLM-C); Instituto de Salud Carlos
III, Proyectos de Investigación en Salud DTS20/00138 (for JS and
MLM-C); Departamento de Industria del Gobierno Vasco (for
MLM-C); Ministerio de Ciencia, Innovación y Universidades
MICINN: SAF2017-87301-R and RTI2018-096759-A-100 integrado
en el Plan Estatal de Investigación Cientifica y Técnica y
Innovación, cofinanciado con Fondos FEDER (for MLM-C and
TCD, respectively); BIOEF (Basque Foundation for Innovation and
Health Research); EITB Maratoia BIO15/CA/014; Asociación
Española contra el Cáncer (MLM-C, TCD); Fundación Científica de
la Asociación Española Contra el Cancer (AECC Scientific Foundation)
Rare Tumor Calls 2017 (for MLM); La Caixa Foundation
Program (for MLM); Fundacion BBVA UMBRELLA project (for
MLM); BFU2015-70067-REDC, BFU2016-77408-R, and BES-2017-
080435 (MINECO / FEDER, UE) and the FIGHT-CNNM2 project
from the EJP RD Joint Transnational Call (JTC2019) (Ref. AC19/
00073) (for LAM-C); RTI2018-095134-B-100 and Grupos de
Investigación del Sistema Universitario Vasco (IT971-16) (for PA);
National Institutes of Health under grant CA217817 (for DB);
AGL2014-54585-R, AGL-2017-86927-R and EQC2018-004897-P
from MINECO; PC0148-2016-0149 and PAI-BIO311 from Junta
de Andalucía (for FM). Ciberehd_ISCIII_MINECO is funded by the
Instituto de Salud Carlos III. We thank Silence Therapeutics plc.
for the financial support provided. We thank MINECO for the
Severo Ochoa Excellence Accreditation to CIC bioGUNE (SEV-
2016-0644)
Cruise Summary Report - MEDWAVES survey. MEDiterranean out flow WAter and Vulnerable EcosystemS (MEDWAVES)
The MEDWAVES (MEDiterranean out flow WAter and Vulnerable EcosystemS) cruise targeted areas under the potential influence of the MOW within the Mediterranean and Atlantic realms. These include seamounts where Cold-water corals (CWCs) have been reported but that are still poorly known, and which may act as essential “stepping stones” connecting fauna of seamounts in the Mediterranean with those of the continental shelf of Portugal, the Azores and the Mid-Atlantic Ridge. During MEDWAVES sampling has been conducted in two of the case studies of ATLAS: Case study 7 (Gulf of Cádiz-Strait of Gibraltar-Alboran Sea) and Case study 8 (Azores).
The initially targeted areas in the Atlantic were: the Gazul Mud volcano, in the Gulf of Cádiz (GoC) area, included in the case study 7, and the Atlantic seamounts Ormonde (Portuguese shelf) and Formigas (by Azores), both part of the case study 8. In the Mediterranean the targeted areas were The Guadiaro submarine canyon and the Seco de los Olivos (also known as Chella Bank) seamount. Unfortunately it was not possible to sample in Guadiaro due to time constraints originated by adverse meteorological conditions which obligate us to reduce the time at sea focusing only in 4 of the 5 initially planned areas.
MEDWAVES was structured in two legs; the first leg took place from the 21st September (departure from Cádiz harbour in Spain) to the 13th October 2016 (arrival in Ponta Delgada, São Miguel, Azores, Portugal took place the 8th of October due to the meteorological conditions that obligated to conclude the first leg earlier as planned). during the Leg 1 sampling was carried out in Gazul, Ormonde and Formigas. The second leg started the 14th October (departure from Ponta Delgada) and finished the 26th October (arrival in Málaga harbour, Spain). MEDWAVES had a total of 30 effective sampling days, being 6 days not operative due to the adverse meteorological conditions experienced during the first leg which forced us to stay in Ponta Delgada from the 08th to the 13th October.
During MEDWAVES the daily routine followed a similar scheme, depending of course on the weather and sea conditions. The main activity during the day, starting early in the morning (around 08:00 AM, once the night activities were finished), was the ROV deployment. Generally a single ROV dive of around 8 hours was performed, however in several occasions two dives were carried out in the same day (see General station list, Appendix II). After the ROV (and sometimes between two dives) the Box Corer and/or Van Veen Grab and/or Multicore was deployed. After these activities, during the night CTD-Rosette deployments and MB was conducted. Accordingly to this schema the scientific personnel worked in the day or in the night watch.
A total of 215 sampling stations have been covered in MEDWAVES, using the following sampling gears: Multibeam echosounder, CTD-Rosette, LADCP, Box Corer, Van Veen Grab, Multicorer and a Remotely Operated Vehicle (ROV). Table 1 sumamrised the number of sampling stations conducted with each gear in each sampling zone. Additionally MB surveys have been conducted during the transits between area
Reflexión Política. Volumen 5 No. 10 de 2003
La democracia local es tema de la mayor importancia. Las instituciones colombianas desde 1991 la fortalecieron, a efecto de diputar a todo el pueblo para que, en cada lugar, atienda directamente sus propios problemas, y proteja mediante su acción de control administrativo los programas que, el mismo pueblo anhela, y plantea antes de la escogencia de sus mandatarios. En Colombia se está implantando una reforma política que ha modificado el sistema electoral, orientada a fortalecer los partidos políticos, fuentes del poder y sustento de la democracia como sistemaLocal democracy is a matter of the greatest importance. Since 1991, Colombian institutions have strengthened it, in order to deputize all the people so that, in each place, they directly address their own problems, and protect through their action of administrative control the programs that the people themselves long for, and propose before the choice of their leaders. In Colombia, a political reform is being implemented that has modified the electoral system, aimed at strengthening political parties, sources of power and support of democracy as a system
The wide-field, multiplexed, spectroscopic facility WEAVE : survey design, overview, and simulated implementation
Funding for the WEAVE facility has been provided by UKRI STFC, the University of Oxford, NOVA, NWO, Instituto de Astrofísica de Canarias (IAC), the Isaac Newton Group partners (STFC, NWO, and Spain, led by the IAC), INAF, CNRS-INSU, the Observatoire de Paris, Région Île-de-France, CONCYT through INAOE, Konkoly Observatory (CSFK), Max-Planck-Institut für Astronomie (MPIA Heidelberg), Lund University, the Leibniz Institute for Astrophysics Potsdam (AIP), the Swedish Research Council, the European Commission, and the University of Pennsylvania.WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366-959 nm at R ∼ 5000, or two shorter ranges at R ∼ 20,000. After summarising the design and implementation of WEAVE and its data systems, we present the organisation, science drivers and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for ∼ 3 million stars and detailed abundances for ∼ 1.5 million brighter field and open-cluster stars; (ii) survey ∼ 0.4 million Galactic-plane OBA stars, young stellar objects and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey ∼ 400 neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionised gas in z 1 million spectra of LOFAR-selected radio sources; (viii) trace structures using intergalactic/circumgalactic gas at z > 2. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator.PostprintPeer reviewe
The wide-field, multiplexed, spectroscopic facility WEAVE: Survey design, overview, and simulated implementation
WEAVE, the new wide-field, massively multiplexed spectroscopic survey
facility for the William Herschel Telescope, will see first light in late 2022.
WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a
nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini'
integral field units (IFUs), and a single large IFU. These fibre systems feed a
dual-beam spectrograph covering the wavelength range 366959\,nm at
, or two shorter ranges at . After summarising the
design and implementation of WEAVE and its data systems, we present the
organisation, science drivers and design of a five- to seven-year programme of
eight individual surveys to: (i) study our Galaxy's origins by completing
Gaia's phase-space information, providing metallicities to its limiting
magnitude for 3 million stars and detailed abundances for
million brighter field and open-cluster stars; (ii) survey million
Galactic-plane OBA stars, young stellar objects and nearby gas to understand
the evolution of young stars and their environments; (iii) perform an extensive
spectral survey of white dwarfs; (iv) survey
neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and
kinematics of stellar populations and ionised gas in cluster galaxies;
(vi) survey stellar populations and kinematics in field galaxies
at ; (vii) study the cosmic evolution of accretion
and star formation using million spectra of LOFAR-selected radio sources;
(viii) trace structures using intergalactic/circumgalactic gas at .
Finally, we describe the WEAVE Operational Rehearsals using the WEAVE
Simulator.Comment: 41 pages, 27 figures, accepted for publication by MNRA
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
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