3,110 research outputs found
Perfomance analysis of hybrid systems based on externally heayed closed-cycle engines
This work presents a comparative analysis of hybrid
systems that make use of closed-cycle externally heated
bottoming systems. Two options are considered:
reciprocating (Stirling) engines and supercritical carbon
dioxide turbines. These engines share the common
feature of working on closed cycles with optimised fluids
(H2 and CO2 respectively). However, they differ in their
internal structure: Stirling engines make use of volumetric
machinery whereas the SCO2 system is composed by
turbomachinery. In both cases, the working fluid is
subjected to very high pressure and temperature in the
range of 50-200 bar and 40-650 ºC.
A brief description of both bottoming systems is
provided in the article along with the expected
performance of each case in on-design and off-design
(part load) conditions. The analysis is therefore split into
two stages. First, a comparison is shown for on-design
operation aiming to evaluate the maximum efficiency
attainable by the proposed systems. Second, a
preliminary analysis of off-design operation is presented.
The paper concludes that hybrid systems based on
atmospheric fuel cells and externally heated closed-cycle
bottoming engines have the potential to outperform
conventional pressurised fuel cells and gas turbines
hybrids while preserving the topping system from the
demanding operating conditions of the latter configuratio
Fibropapilomatosis oral múltiple como manifestación inicial de SÃndrome de Cowden: caso clÃnico
El sÃndrome de Cowden es una infrecuente enfermedad hereditaria englobada dentro de las poliposis gastrointestinales de tipo hamartomatoso. Se caracteriza por asociar anomalÃas cutaneomucosas y por la extraordinaria tendencia a desarrollar neoplasias malignas, principalmente de mama y tiroides. La importancia de un diagnóstico precoz del sÃndrome y de un adecuado screening tumoral en pacientes con lesiones papilomatosas cutaneomucosas, nos va a permitir adelantarnos en el diagnóstico de patologÃas con enorme morbimortalidad asociada en caso de una detección tardÃa. Presentamos el caso de una paciente diagnosticada de sÃndrome de Cowden tras consultar por lesiones papilomatosas labiales de largo tiempo de evolución y tratada posteriormente de cáncer de mama y riñón en estadios iniciales.
El correcto diagnóstico de una patologÃa banal de mucosa oral, nos ha permitido actuar de manera muy precoz frente a la patologÃa neoplásica asociada a dicha enfermedad.Cowden syndrome is a rare hereditary disease included within hamartoma-type gastrointestinal polyposis. It is characterised by associated mucocutaneous anomalies and by the extraordinary tendency to develop malignant neoplasia, mainly in the breast and thyroid. Early diagnosis of the syndrome and adequate tumoral screening in patients with mucocutaneous papillomatosis make it possible to make an earlier diagnosis of associated pathologies which have great morbidity when detected late. We present the case of a patient diagnosed with Cowden syndrome after consultation for labial papillomatous lesions of long evolution who was subsequently treated for breast and kidney cancer in initial stages.
The correct diagnosis of a banal pathology of oral mucosa made it possible for us to take early action against the neoplastic pathology associated with this disease
Multiple oral fibropapillomatosis as an initial manifestation of Cowden Syndrome : case report
El sÃndrome de Cowden es una infrecuente enfermedad hereditaria englobada dentro de las poliposis gastrointestinales de tipo hamartomatoso. Se caracteriza por asociar anomalÃas cutaneomucosas y por la extraordinaria tendencia a desarrollar neoplasias malignas, principalmente de mama y tiroides. La importancia de un diagnóstico precoz del sÃndrome y de un adecuado screening tumoral en pacientes con lesiones papilomatosas cutaneomucosas, nos va a permitir adelantarnos en el diagnóstico de patologÃas con enorme morbimortalidad asociada en caso de una detección tardÃa. Presentamos el caso de una paciente diagnosticada de sÃndrome de Cowden tras consultar por lesiones papilomatosas labiales de largo tiempo de evolución y tratada posteriormente de cáncer de mama y riñón en estadios iniciales. El correcto diagnóstico de una patologÃa banal de mucosa oral, nos ha permitido actuar de manera muy precoz frente a la patologÃa neoplásica asociada a dicha enfermedad
Systematics of detrital zircon U–Pb ages from Cambrian–Lower Devonian rocks of northern Morocco with implications for the northern Gondwanan passive margin
This study was found by the Ministerio de Economia y Competitividad (MINECO) of Spain through the project PANGEATOR (CGL2015-71692) and the Pre-Doctoral scholarship BES-2016-078168. We are indebted to Mike Hall and Brad McDonald for their assistance and technical support on sample preparation and the LA-ICPMS, respectively. The CL imaging was carried out on the Curtin University's Microscopy & Microanalysis Facility, whose instrumentation has been partially funded by the University, State and Commonwealth Governments, and the Scanning Electron Microscope (SEM) Facility at the University of Edinburgh. Analysis in the SHRIMP and GeoHistory Facilities, JdLC, Curtin University were enabled by AuScope (auscope.org.au) and the Australian Government via the National Collaborative Research Infrastructure Strategy (NCRIS) and an Australian Geophysical Observing System grant provided to AuScope Pty Ltd. by the AQ44 Australian Education Investment Fund program, respectively. The NPII multi-collector was obtained via funding from the Australian Research Council LIEF program (LE150100013). The SIMS analyses were performed at the NERC Ion Microprobe Facility of the University of Edinburgh (UK). Comments from two anonymous reviewers and editorial handling by Prof. Victoria Pease are acknowledged. Funding for open access charge: YUniversidad de Granada / CBUA.The systematic acquisition of U–Pb geochronological data from detrital zircon grains has become an essential
tool in tectonic studies focused on reconstructing the pre–Variscan geography of the northern Gondwanan
passive margin. New detrital zircon ages for 16 samples from the Cambrian–Lower Devonian succession of the
Moroccan Mesetas (northern Morocco) are reported here. The results, combined with previously published data,
reassert the strong West African Craton affinity of the Paleozoic sedimentary rocks, characterized by dominant
Cadomian/Pan–African (c. 850–540 Ma) and Eburnean (c. 2.2–1.9 Ga) detrital zircon populations and a minor
Leonian/Liberian (c. 2.5 Ga) population. Primary sources of these zircon grains are well established as the West
African Craton located just to the south, but also in the Precambrian basement that locally crops out in the
Moroccan Mesetas themselves. During the Cambrian–Early Ordovician, erosion preferentially dismantled
Cadomian (c. 590–540 Ma) arc–derived rocks of the Gondwanan continental margin, while later, the slightly
older Pan–African (c. 650–600 Ma) basement became the main sediment source. In the studied samples, irregularly
present minor detrital zircon populations suggest additional sediment provenance from secondary sources
such as: (i) remote northeastern African cratons (e.g., Saharan Metacraton and/or Arabian–Nubian Shield) that
likely could have provided the c. 1.1–0.9 Ga and, possibly, the c. 1.9–1.7 Ga zircon grains, and (ii) rift–related
Cambrian–Early Ordovician volcanic centers in the Moroccan Mesetas that supplied heterogeneously distributed
– although locally dominant in small areas – sedimentary detritus before rift abortion and burial underneath the
overlying passive margin sedimentary succession.Ministerio de Economia y Competitividad (MINECO) of Spain through the project PANGEATOR CGL2015-71692Scanning Electron Microscope (SEM) Facility at the University of EdinburghAustralian Geophysical Observing System grant by AQ44 Australian Education Investment Fund programAustralian Research Council LE150100013Universidad de Granada / CBUA
BES-2016-07816
Mesonia oceanica sp. Nov., isolated from oceans during the tara oceans expedition, with a preference for mesopelagic waters
Strain ISS653T, isolated from Atlantic seawater, is a yellow pigmented, non-motile, Gram-reaction-negative rod-shaped bac-terium, strictly aerobic and chemoorganotrophic, slightly halophilic (1-15% NaCl) and mesophilic (4-37 °C), oxidase-and catalase-positive and proteolytic. Its major cellular fatty acids are iso-C15:0, iso-C15:0 2-OH, and iso-C17:0 3-OH; the major identified phospholipid is phosphatidylethanolamine and the major respiratory quinone is MK6. Genome size is 4.28 Mbp and DNA G+C content is 34.9 mol%. 16S rRNA gene sequence similarity places the strain among members of the family Flavobacteriaceae, with the type strains of Mesonia phycicola (93.2%), Salegentibacter mishustinae (93.1%) and Mesonia mobilis (92.9%) as closest relatives. Average amino acid identity (AAI) and average nucleotide identity (ANI) indices show highest values with M. mobilis (81% AAI; 78.9% ANI), M. phycicola (76% AAI; 76.3% ANI), Mesonia maritima (72% AAI, 74.9% ANI), Mesonia hippocampi (64% AAI, 70.8% ANI) and Mesonia algae (68% AAI; 72.2% ANI). Phylogenomic analysis using the Up-to-date-Bacterial Core Gene set (UBCG) merges strain ISS653T in a clade with species of the genus Mesonia. We conclude that strain ISS653T represents a novel species of the genus Mesonia for which we propose the name Mesonia oceanica sp. nov., and strain ISS653T (=CECT 9532T=LMG 31236T) as the type strain. A second strain of the species, ISS1889 (=CECT 30008) was isolated from Pacific Ocean seawater. Data obtained throughout the Tara oceans expedition indicate that the species is more abundant in the mesopelagic dark ocean than in the photic layer and it is more frequent in the South Pacific, Indian and North Atlantic oceans
Enhanced molecular spin-photon coupling at superconducting nanoconstrictions
We combine top-down and bottom-up nanolithography to optimize the coupling of small molecular spin ensembles to 1.4 GHz on-chip superconducting resonators. Nanoscopic constrictions, fabricated with a focused ion beam at the central transmission line, locally concentrate the microwave magnetic field. Drops of free-radical molecules have been deposited from solution onto the circuits. For the smallest ones, the molecules were delivered at the relevant circuit areas by means of an atomic force microscope. The number of spins Neff effectively coupled to each device was accurately determined combining Scanning Electron and Atomic Force Microscopies. The collective spin-photon coupling constant has been determined for samples with Neff ranging between 2 × 106 and 1012 spins, and for temperatures down to 44 mK. The results show the well-known collective enhancement of the coupling proportional to the square root of Neff. The average coupling of individual spins is enhanced by more than 4 orders of magnitude (from 4 mHz up to above 180 Hz), when the transmission line width is reduced from 400 μm down to 42 nm, and reaches maximum values near 1 kHz for molecules located on the smallest nanoconstrictions.The authors acknowledge funding from the EU (COST Action 15128 MOLSPIN, QUANTERA SUMO and MICROSENSE projects, FET-OPEN Grant 862893 FATMOLS), the Spanish MICINN (Grants RTI2018-096075-B-C21, PCI2018-093116, MAT2017-89993-R, MAT2017-88358-C3-1-R, EUR2019-103823), the Gobierno de Aragón Ggrants E09-17R Q-MAD, E35-20R, BE and LMP55-18, FANDEPAM) and the BBVA foundation (Leonardo Grants 2018 and 2019).Peer reviewe
Study of the Secondary Electron Yield in Dielectrics Using Equivalent Circuital Models
© 2018 IEEE. Personal use of this material is permitted. PermissÃon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisÃng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] Secondary electron emission has an important role on the triggering of the multipactor effect; therefore, its study and characterization are essential in radio-frequency waveguide applications. In this paper, we propose a theoretical model, based on equivalent circuit models, to properly understand charging and discharging processes that occur in dielectric samples under electron irradiation for secondary electron emission characterization. Experimental results obtained for Pt, Si, GaS, and Teflon samples are presented to verify the accuracy of the proposed model. Good agreement between theory and experiments has been found.The authors would like to thank the European High Power Space Materials Laboratory for its contribution-a laboratory funded by the European Regional Development Fund-a way of making Europe. Many thanks to the University of Valencia (Spain) for supporting this research activity with the internal program "Assistance for temporary stays of invited researchers within the framework of the Subprogramme Attraction of Talent 2015".Bañón, D.; Socuellamos, JM.; Mata-Sanz, R.; Mercadé-Morales, L.; Gimeno MartÃnez, B.; Boria Esbert, VE.; Raboso GarcÃa-Baquero, D.... (2018). Study of the Secondary Electron Yield in Dielectrics Using Equivalent Circuital Models. IEEE Transactions on Plasma Science. 46(4):859-867. https://doi.org/10.1109/TPS.2018.2809602S85986746
COVID-19 after two years: trajectories of different components of mental health in the Spanish population
Aims:
Our study aimed to (1) identify trajectories on different mental health components during a two-year follow-up of the COVID-19 pandemic and contextualise them according to pandemic periods; (2) investigate the associations between mental health trajectories and several exposures, and determine whether there were differences among the different mental health outcomes regarding these associations.
Methods:
We included 5535 healthy individuals, aged 40–65 years old, from the Barcelona Brain Health Initiative (BBHI). Growth mixture models (GMM) were fitted to classify individuals into different trajectories for three mental health-related outcomes (psychological distress, personal growth and loneliness). Moreover, we fitted a multinomial regression model for each outcome considering class membership as the independent variable to assess the association with the predictors.
Results:
For the outcomes studied we identified three latent trajectories, differentiating two major trends, a large proportion of participants was classified into ‘resilient’ trajectories, and a smaller proportion into ‘chronic-worsening’ trajectories. For the former, we observed a lower susceptibility to the changes, whereas, for the latter, we noticed greater heterogeneity and susceptibility to different periods of the pandemic. From the multinomial regression models, we found global and cognitive health, and coping strategies as common protective factors among the studied mental health components. Nevertheless, some differences were found regarding the risk factors. Living alone was only significant for those classified into ‘chronic’ trajectories of loneliness, but not for the other outcomes. Similarly, secondary or higher education was only a risk factor for the ‘worsening’ trajectory of personal growth. Finally, smoking and sleeping problems were risk factors which were associated with the ‘chronic’ trajectory of psychological distress.
Conclusions:
Our results support heterogeneity in reactions to the pandemic and the need to study different mental health-related components over a longer follow-up period, as each one evolves differently depending on the pandemic period. In addition, the understanding of modifiable protective and risk factors associated with these trajectories would allow the characterisation of these segments of the population to create targeted interventions"This work was supported by a grant from the Agència de Gestió d'Ajuts Universitaris i de Recerca (AGAUR) ‘PANDÈMIES 2020’ (ref. 2020PANDE00043) and a grant from ‘La Marató de TV3’ MARATÓ 2020 COVID-19 (ref. 202129–31). Supported in part by the Spanish Ministry of Science, Innovation and Universities (MICIU/FEDER; grant number RTI2018-095181-B-C21) and an ICREA Academia 2019 grant award to D. B-F. Partially, this research has received funding from ‘La Caixa’ Foundation (grant number LCF/PR/PR16/11110004), and from Institut Guttmann and Fundació Abertis. I.B-M. was supported by a postdoctoral fellowship related to ‘PANDÈMIES 2020’ (AGAUR; 2020PANDE00043). D.F. has been supported by grant 2021 SGR 01421 (GRBIO) administrated by the Departament de Recerca I Universitats de la Generalitat de Catalunya (Spain) and by the Ministerio de Ciencia e Innovación (Spain) [PID2019-104830RB-I00/ DOI (AEI): 10.13039/501100011033].. J.M.T. was partly supported by AGAUR (2018 PROD 00172), Fundació Joan Ribas Araquistain and ‘La Marató de TV3’ Fundation (201735.10). This research was furthermore supported by the Government of Catalonia (2017SGR748). We also acknowledge support from the Spanish Ministry of Science and Innovation and State Research Agency through the ‘Centro de Excelencia Severo Ochoa 2019-2023’ Program (CEX2018-000806-S), and support from the Generalitat de Catalunya through the CERCA Program"Peer ReviewedPostprint (published version
Adalimumab reduces photoreceptor cell death in a mouse model of retinal degeneration
Growing evidence suggests that inflammation is involved in the progression of retinitis pigmentosa (RP) both in patients and in animal models. The aim of this study was to investigate the effect of Adalimumab, a monoclonal anti-TNFα antibody, on retinal degeneration in a murine model of human autosomal recessive RP, the rd10 mice at postnatal day (P) 18. In our housing conditions, rd10 retinas were seriously damaged at P18. Adalimumab reduced photoreceptor cell death, as determined by scoring the number of TUNEL-positive cells. In addition, nuclear poly (ADP) ribose (PAR) content, an indirect measure of PAR polymerase (PARP) activity, was also reduced after treatment. The blockade of TNFα ameliorated reactive gliosis, as visualized by decreased GFAP and IBA1 immunolabelling (Müller cell and microglial markers, respectively) and decreased up-regulation of TNFα gene expression. Adalimumab also improved antioxidant response by restoring total antioxidant capacity
and superoxide dismutase activity. Finally, we observed that Adalimumab normalized energetic and metabolic pattern in rd10 mouse retinas. Our study suggests that the TNFα blockade could be
a successful therapeutic approach to increase photoreceptor survival during the progression of RP. Further studies are needed to characterize its effect along the progression of the diseaseThis work was supported by the European Regional Development Fund, Institute of Health Carlos III, PI12/0481, SAF2013-41059-R and SAF2013-41945 from the Spanish Ministry of Economy and Competitiveness (MEC). CIBERER is an initiative of the Institute of Health Carlos III from the MEC. Regina Rodrigo has a research-contract SNS Miguel Servet (CP09/118) from Institute of Health Carlos II
Van Der Waals Heteroepitaxy of GaSe and InSe, Quantum Wells and Superlattices
Bandgap engineering and quantum confinement in semiconductor heterostructures
provide the means to fine-tune material response to electromagnetic fields and
light in a wide range of the spectrum. Nonetheless, forming semiconductor
heterostructures on lattice-mismatched substrates has been a challenge for
several decades, leading to restrictions for device integration and the lack of
efficient devices in important wavelength bands. Here, we show that the van der
Waals epitaxy of two-dimensional (2D) GaSe and InSe heterostructures occur on
substrates with substantially different lattice parameters, namely silicon and
sapphire. The GaSe/InSe heterostructures were applied in the growth of quantum
wells and superlattices presenting photoluminescence and absorption related to
interband transitions. Moreover, we demonstrate a self-powered photodetector
based on this heterostructure on Si that works in the visible-NIR wavelength
range. Fabricated at wafer-scale, these results pave the way for an easy
integration of optoelectronics based on these layered 2D materials in current
Si technology.Comment: 16 Pages, 5 figures. Supplementary Information included in the end
(+10 pages, +10 Figures, + 2 Tables). Partially presented at 21st ICMBE -
September 202
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