3 research outputs found
Flexible fMRI Processing Pipeline for Large- Scale Studies of Functional Connectivity in Preclinical Alzheimer’s Disease
No full textTreballs Finals de Grau d'Enginyeria Biomèdica. Facultat de Medicina i Ciències de la Salut. Universitat de Barcelona. Curs: 2024-2025. Tutor: Roser Sala Llonch, , Raúl Tudela FernándezEl cervell es pot entendre com una xarxa complexa de regions espacialment distribuïdes, però funcional-
ment interconnectades que comparteixen informació contínuament. La connectivitat funcional (FC), que
mesura com les regions del cervell es comuniquen i coordinen, pot ajudar a identificar signes inicials
de malalties com l’Alzheimer (AD). Aquest projecte té com a objectiu implementar un pipeline flexible
per processar dades de ressonància magnètica funcional en repòs (rs-fMRI) i estudiar la FC en etapes
preclíniques de l’AD.
Un conjunt de dades de més de 1.000 subjectes ha estat processat mitjançant un pipeline flexible,
que consisteix en una sèrie de passos com l’extracció cerebral, la correcció de moviment i la reducció de
soroll, dissenyats per preparar les dades per a posteriors anàlisis. A més, s’ha desenvolupat una aplicació
de control de qualitat (QC), que combina la inspecció visual i mètriques quantitatives per garantir resultats
fiables, amb 76% dels subjectes superant el QC. Tots els procediments desenvolupats en aquest projecte
estan disponibles en un repositori de GitHub.
Els resultats demostren una relació significativa entre la FC i l’escala Centiloid, una mesura de la
progressió de l’AD. També s’han identificat canvis en la connectivitat cerebral relacionats amb l’edat,
mostrant potenciació i deteriorament de connexions, indicant una redistribució de les xarxes cerebrals.
Finalment, s’ha introduït un marc exploratori per analitzar altres factors que poden influir en la funció
cerebral, obrint la porta perquè es pugui utilitzar en futurs estudis de neuroimatge. Investigacions fu-
tures haurien d’avaluar el potencial d’aquests biomarcadors com a indicadors primerencs de malalties
neurodegenerative
Impact of prefrontal theta burst stimulation on clinical neuropsychological tasks [dataset]
No full textThis dataset corresponds to the results published in: Viejo-Sobera, R., Redolar-Ripoll, D., Boixadós, M., Palaus, M., Valero-Cabré, A., & Marron, E. M. (2017). Impact of prefrontal theta burst stimulation on clinical neuropsychological tasks. Frontiers in neuroscience, 11, 462. https://doi.org/10.3389/fnins.2017.00462
The data was collected in 2014-2015 at the Cognitive NeuroLab (cognitiveneurolab.org, Universitat Oberta de Catalunya, UOC) as part of a project founded by the Spanish Ministerio de Economía y Competitividad (grant number: PSI2012-36610; PI Diego Redolar Ripoll).
For more information contact the corresponding author Raquel Viejo-Sobera ([email protected])
CALIOPE-Urban v1.0: Coupling R-LINE with a mesoscale air quality modelling system for urban air quality forecasts over Barcelona city (Spain)
No full textThe NO2 annual air quality limit value is systematically exceeded in many European cities. In this context, understanding human exposure, improving policy and planning, and providing forecasts requires the development of accurate air quality models at the urban (street level) scale. We describe CALIOPE-Urban, a system coupling CALIOPE - an operational mesoscale air quality forecast system based on the HERMES (emissions), WRF (meteorology) and CMAQ (chemistry) models - with the urban roadway dispersion model R-LINE. Our developments have focused on Barcelona city (Spain), but the methodology may be replicated for other cities in the future. WRF drives pollutant dispersion and CMAQ provides background concentrations to R-LINE. Key features of our system include the adaptation of R-LINE to street canyons, the use of a new methodology that considers upwind grid cells in CMAQ to avoid double counting traffic emissions, a new method to estimate local surface roughness within street canyons, and a vertical mixing parameterisation that considers urban geometry and atmospheric stability to calculate surface level background concentrations. We show that the latter is critical to correct the night-time overestimations in our system. Both CALIOPE and CALIOPE-Urban are evaluated using two sets of observations. The temporal variability is evaluated against measurements from five traffic sites and one urban background site for April-May 2013. While both systems show a fairly good agreement at the urban background site, CALIOPE-Urban shows a better agreement at traffic sites. The spatial variability is evaluated using 182 passive dosimeters that were distributed across Barcelona during 2 weeks for February-March 2017. In this case, the coupled system also shows a more realistic distribution than the mesoscale system, which systematically underpredicts NO2 close to traffic emission sources. Overall CALIOPE-Urban improves mesoscale model results, demonstrating that the combination of both scales provides a more realistic representation of NO2 spatio-temporal variability in Barcelona. © Author(s) 2019.Acknowledgements. Jaime Benavides’ PhD work is funded by grant BES-2014-070637 from the FPI programme by the Spanish Ministry of the Economy and Competitiveness. Jaime Benavides developed part of this work as a research visitor at the Institute for the Environment at UNC funded by mobility grant EEBB-I-17-12296 from the same ministry. IDAEA-CSIC acknowledges the Barcelona City Council for their support to the experimental campaign. Carlos Pérez García-Pando acknowledges the long-term support from the AXA Chair in Sand and Dust Storms (AXA Research Fund), as well as the support received through the Ramón y Ca-jal programme (grant RYC-2015-18690) of the Spanish Ministry of Economy and Competitiveness.Peer reviewe
