8,921 research outputs found

    Charge instabilities and topological phases in the extended Hubbard model on the honeycomb lattice with enlarged unit cell

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    We study spontaneous symmetry breaking in a system of spinless fermions in the Honeycomb lattice paying special emphasis to the role of an enlarged unit cell on time reversal symmetry broken phases. We use a tight binding model with nearest neighbor hopping t and Hubbard interaction V1 and V2 and extract the phase diagram as a function of electron density and interaction within a mean field variational approach. The analysis completes the previous work done in Phys. Rev. Lett. 107, 106402 (2011) where phases with non--trivial topological properties were found with only a nearest neighbor interaction V1 in the absence of charge decouplings. We see that the topological phases are suppressed by the presence of metallic charge density fluctuations. The addition of next to nearest neighbor interaction V2 restores the topological non-trivial phases

    Diatoms as a paleoproductivity proxy in the NW Iberian coastal upwelling system (NE Atlantic)

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    The objective of the current work is to improve our understanding of how water column diatom's abundance and assemblage composition is seasonally transferred from the photic zone to seafloor sediments. To address this, we used a dataset derived from water column, sediment trap and surface sediment samples recovered in the NW Iberian coastal upwelling system. Diatom fluxes (2.2 (+/- 5.6) 10(6) valves m(-2) d(-1)) represented the majority of the siliceous microorganisms sinking out from the photic zone during all studied years and showed seasonal variability. Contrasting results between water column and sediment trap diatom abundances were found during downwelling periods, as shown by the unexpectedly high diatom export signals when diatom- derived primary production achieved their minimum levels. They were principally related to surface sediment remobilization and intense Minho and Douro river discharge that constitute an additional source of particulate matter to the inner continental shelf. In fact, contributions of allochthonous particles to the sinking material were confirmed by the significant increase of both benthic and freshwater diatoms in the sediment trap assemblage. In contrast, we found that most of the living diatom species blooming during highly productive upwelling periods were dissolved during sinking, and only those resistant to dissolution and the Chaetoceros and Leptocylindrus spp. resting spores were susceptible to being exported and buried. Fur-thermore, Chaetoceros spp. dominate during spring-early summer, when persistent northerly winds lead to the upwelling of nutrient-rich waters on the shelf, while Leptocylindrus spp. appear associated with late-summer upwelling relaxation, characterized by water column stratification and nutrient depletion. These findings evidence that the contributions of these diatom genera to the sediment's total marine diatom assemblage should allow for the reconstruction of different past upwelling regimes.CAIBEX [CTM2007-66408-C02-01/MAR]; REIMAGE [CTM2011-30155-C03-03]; Spanish Government, EXCAPA project [10MDS402013PR]; Xunta de Galicia; EU FEDER [INTERREG 2009/2011-0313/RAIA/E]; RAIA. co [INTERREG2011/2013-052/RAIA.co/1E]; CALIBERIA project [PTDC/MAR/102045/2008]; Fundacao para a Ciencia e a Tecnologia (FCT-Portugal) [COMPETE/FEDER-FCOMP01-0124-FEDER-010599]; Xunta de Galicia (Spain) [SFRH/BPD/111433/2015]; FCT (Portugal) [SFRH/BPD/111433/2015]; [SFRH/BD/88439/2012

    Patients’ and physicians’ perceptions of teleconsultations

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    Funding Information: The Regional Health Administration of Lisbon and Tagus Valley funded Dr. Maria's salary and had no role in the study design, data collection, analysis or writing of this article. The present publication was funded by Fundação Ciência e Tecnologia, IP national support through CHRC (UIDP/04923/2020). Publisher Copyright: © The Author(s) 2022.Introduction: Previous qualitative research on teleconsultations has focused on synchronous communication between a patient and a clinician. This study aims to explore physicians' and patients' perceptions of the interaction on the interface between primary care and the Cardiology service of a referral hospital through teleconsultations. Methods: This qualitative study was embedded in an organizational case study concerning the introduction and rollout of a new service model that took place at the point of care. The patients and physicians were recruited for semi-structured interviews until thematic saturation was achieved, between September 2019 - January 2020. The interviews were audiorecorded and anonymized. The transcribed interviews were stored, coded, and analyzed in MAXQDA, following the steps for conventional content analysis. Results: A total of 29 participants were interviewed. Patients and physicians presented clear views about the role of the GP and the cardiologist and their function in overall structure of healthcare. GPs felt their role was to bring expertise in the patient which could supplement the cardiologists' expertise on the condition. However, GPs had to renegotiate roles in the teleconsultations when they saw themselves in a new situation, together with another physician and the patient. Conclusions: Our findings suggest that joint teleconsultations can promote continuity of care for patients in the primary/secondary care interface. Active coordination between physicians with delineation of roles throughout primary-secondary care interface is needed to manage selected patients who may benefit the most from shared care.publishersversionpublishe

    Towards a Universal Semantic Dictionary

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    [EN] A novel method for finding linear mappings among word embeddings for several languages, taking as pivot a shared, multilingual embedding space, is proposed in this paper. Previous approaches learned translation matrices between two specific languages, while this method learns translation matrices between a given language and a shared, multilingual space. The system was first trained on bilingual, and later on multilingual corpora as well. In the first case, two different training data were applied: Dinu¿s English¿Italian benchmark data, and English¿Italian translation pairs extracted from the PanLex database. In the second case, only the PanLex database was used. The system performs on English¿Italian languages with the best setting significantly better than the baseline system given by Mikolov, and it provides a comparable performance with more sophisticated systems. Exploiting the richness of the PanLex database, the proposed method makes it possible to learn linear mappings among an arbitrary number of languages.This research was funded by Spanish MINECO and FEDER grant number TIN2017-85854-C4-2-R.Castro-Bleda, MJ.; Iklódi, E.; Recski, G.; Borbély, G. (2019). Towards a Universal Semantic Dictionary. Applied Sciences. 9(19):1-14. https://doi.org/10.3390/app9194060S114919Youn, H., Sutton, L., Smith, E., Moore, C., Wilkins, J. F., Maddieson, I., … Bhattacharya, T. (2016). On the universal structure of human lexical semantics. Proceedings of the National Academy of Sciences, 113(7), 1766-1771. doi:10.1073/pnas.1520752113Ruder, S., Vulić, I., & Søgaard, A. (2019). A Survey of Cross-lingual Word Embedding Models. Journal of Artificial Intelligence Research, 65, 569-631. doi:10.1613/jair.1.11640Bojanowski, P., Grave, E., Joulin, A., & Mikolov, T. (2017). Enriching Word Vectors with Subword Information. Transactions of the Association for Computational Linguistics, 5, 135-146. doi:10.1162/tacl_a_0005

    Intracellular trafficking of prohormones and proneuropeptides: Cell type-specific sorting and targeting

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    Hormones and neuropeptides are usually synthesized as large precursor molecules which must undergo a series of post-translational modifications before they are released from secretory vesicles after stimulation by specific secretagogues. The classical vectorial transport of precursors and mature peptide products from the endoplasmic reticulum (ER) to their site of release has been the subject of intensive studies during the past 25 years, but there are a number of unresolved issues which still challenge cell biologists. The main issues are: (i) the molecular mechanisms underlying targeting and sorting of prohormones within the eukaryotic secretory pathway; (ii) further identification and intracellular site of action of post-translational processing enzymes; (iii) tissue-specific processing of hormone and neuropeptide precursors; and (iv) molecular mechanisms underlying intracellular transport ofl hormone and neuropeptide precursors and their cleavage products to alternative intracellular compartments besides the secretory pathway.Fil: Perone, Marcelo Javier. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; Argentina. University of Manchester; Reino UnidoFil: Windeatt, Simon. University of Manchester; Reino UnidoFil: Castro, Maria G.. University of Manchester; Reino Unid

    Cardiorespiratory fitness and sports activities in children and adolescents with solitary functioning kidney

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    Background: An increasing number of children with chronic disease require a complete medical examination to be able to practice physical activity. Particularly children with solitary functioning kidney (SFK) need an accurate functional evaluation to perform sports activities safely. The aim of our study was to evaluate the influence of regular physical activity on the cardiorespiratory function of children with solitary functioning kidney. Method: Twenty-nine patients with congenital SFK, mean age 13.9 ± 5.0 years, and 36 controls (C), mean age 13.8 ± 3.7 years, underwent a cardiorespiratory assessment with spirometry and maximal cardiopulmonary exercise testing. All subjects were divided in two groups: sedentary (S) and trained (T) patients, by means of a standardized questionnaire about their weekly physical activity. Results: We found that mean values of maximal oxygen consumption (VO2max) and exercise time (ET) were higher in T subjects than in S subjects. Particularly SFK-T presented mean values of VO2max similar to C-T and significantly higher than C-S (SFK-T: 44.7 ± 6.3 vs C-S: 37.8 ± 3.7 ml/min/kg; p < 0.0008). We also found significantly higher mean values of ET (minutes) in minutes in SFK-T than C-S subjects (SFK-T: 12.9 ± 1.6 vs C-S: 10.8 ± 2.5 min; p <0.02). Conclusion: Our study showed that regular moderate/high level of physical activity improve aerobic capacity (VO2max) and exercise tolerance in congenital SFK patients without increasing the risks for cardiovascular accidents and accordingly sports activities should be strongly encouraged in SFK patients to maximize health benefit
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