89 research outputs found

    Cerebral vasoreactivity in response to a headof-bed position change is altered in patients with moderate and severe obstructive sleep apnea

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    Obstructive sleep apnea (OSA) can impair cerebral vasoreactivity and is associated with an increased risk of cerebrovascular disease. Unfortunately, an easy-to-use, non-invasive, portable monitor of cerebral vasoreactivity does not exist. Therefore, we have evaluated the use of near-infrared diffuse correlation spectroscopy to measure the microvascular cerebral blood flow (CBF) response to a mild head-of-bed position change as a biomarker for the evaluation of cerebral vasoreactivity alteration due to chronic OSA. Furthermore, we have monitored the effect of two years of continuous positive airway pressure (CPAP) treatment on the cerebral vasoreactivity.Peer ReviewedPostprint (published version

    Construïm un vaixell?

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    Des del convenciment que les ciències s'han d'ensenyar a l'escola a partir de pràctiques experimentals, aquest estudi presenta un projecte realitzat amb alumnes de cinquè de primària del Col·legi Mare Janer amb l'objectiu que arribessin a comprendre el Principi d'Arquímedes d'una manera completament vivencial. A partir de la pregunta "construïm un vaixell?", plantejada pel mestre, i mitjançant la realització prèvia de tot un seguit d'experiments, els alumnes han dissenyat i construït un vaixell capaç de transportar un estudiant.From the belief that sciences should be taught at school through experimental practices, this study presents a project done with fifth grade students from the school Col·legi Maria Janer with the purpose of them understanding the Archimedes' Principle in a completely experimental way. Starting from the question "can we build a boat?", set by the teacher, and with the previous implementation of various experiments, students have designed and build a boat that is able to carry one pupil

    Monitoring groundwater nitrate attenuation in a regional system coupling hydrogeology with multi-isotopic methods: the case of Plana de Vic (Osona, Spain)

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    This paper describes an integrated application of classical hydrogeological methods and multi-isotopic methods (d15N, d18ONO3, d34S, d18OSO4, d13C) to assess the fate of groundwater nitrate in the Osona area, declared vulnerable to nitrate pollution by the Catalan Government in 1998, where nitrate is derived from intensive pig farming activities. Previous studies, involving a small area, indicated the occurrence of denitrification processes and their relationship with pyrite oxidation [Vitòria, L., Soler, A., Canals, A., Otero, N., 2008. Environmental isotopes (N, S, C, O, D) to determine natural attenuation processes in nitrate contaminated waters: example of Osona (NE Spain). Appl. Geochem. 23, 3597-3611]. For the present study, groundwater samples were collected at 60 production wells at three different periods between April 2005 and May 2006 to confirm that denitrification takes place in a larger area than that studied by Vitòria et al. [Vitòria, L., Soler, A., Canals, A., Otero, N., 2008. Environmental isotopes (N, S, C, O, D) to determine natural attenuation processes in nitrate contaminated waters: example of Osona (NE Spain). Appl. Geochem. 23, 3597-3611]. The aim of the study was to characterize the denitrification processes that control natural attenuation and to study their spatial and temporal variations. Nitrate concentration ranged from 10 to 529 mg/l, with 82% of the wells above the drinking water threshold of 50 mg NO3/l. Nitrate isotopic composition ranged from +5.3% to +35.3% for d15N and from +0.4% to +17.6% for d18ONO3 , and the samples showed a positive correlation between d15N and d18ONO3 , with a eN/eO ratio of 1.8, consistent with denitrification processes. The link between denitrification and pyrite oxidation is demonstrated by coupling chemical data with nitrate and sulfate isotopes. Furthermore, a spatial distribution of samples with significant denitrification was observed, allowing us to determine two main hydrogeological zones where natural attenuation was most effective. In several of the studied points, denitrification processes related to pyrite oxidation predominated and an estimation of the isotopic enrichment factors was performed using the temporal variations of nitrate concentration and the isotopic composition of dissolved nitrate (d15NNO3 and d18ONO3). Finally, using estimated isotopic enrichment factors, an approximation of the degree of natural attenuation of nitrate was performed on those samples showing clear denitrification, and a median value of 30% of contaminant diminution was obtained

    Transcranial diffuse optical assessment of the microvascular reperfusion after thrombolysis for acute ischemic stroke

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    In this pilot study, we have evaluated bedside diffuse optical monitoring combining diffuse correlation spectroscopy and near-infrared diffuse optical spectroscopy to assess the effect of thrombolysis with an intravenous recombinant tissue plasminogen activator (rtPA) on cerebral hemodynamics in an acute ischemic stroke. Frontal lobes of five patients with an acute middle cerebral artery occlusion were measured bilaterally during rtPA treatment. Both ipsilesional and contralesional hemispheres showed significant increases in cerebral blood flow, total hemoglobin concentration and oxy-hemoglobin concentration during the first 2.5 hours after rtPA bolus. The increases were faster and higher in the ipsilesional hemisphere. The results show that bedside optical monitoring can detect the effect of reperfusion therapy for ischemic stroke in real-time.Peer ReviewedPostprint (published version

    Design and Development of an AIoT Architecture for Introducing a Vessel ETA Cognitive Service in a Legacy Port Management Solution

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    [EN] Current Internet of Things (IoT) stacks are frequently focused on handling an increasing volume of data that require a sophisticated interpretation through analytics to improve decision making and thus generate business value. In this paper, a cognitive IoT architecture based on FIWARE IoT principles is presented. The architecture incorporates a new cognitive component that enables the incorporation of intelligent services to the FIWARE framework, allowing to modernize IoT infrastructures with Artificial Intelligence (AI) technologies. This allows to extend the effective life of the legacy system, using existing assets and reducing costs. Using the architecture, a cognitive service capable of predicting with high accuracy the vessel port arrival is developed and integrated in a legacy sea traffic management solution. The cognitive service uses automatic identification system (AIS) and maritime oceanographic data to predict time of arrival of ships. The validation has been carried out using the port of Valencia. The results indicate that the incorporation of AI into the legacy system allows to predict the arrival time with higher accuracy, thus improving the efficiency of port operations. Moreover, the architecture is generic, allowing an easy integration of the cognitive services in other domains.Funding This work has been developed under the framework of the COSIBAS project (funded by CDTI research and innovation programme under grant agreement No.EXP 00110912/INNO-20181033) and the EIFFEL project (funded by European Unions Horizon 2020 research and innovation programme under grant agreement No 101003518).Valero López, CI.; Ivancos Pla, E.; Vañó García, R.; Garro, E.; Boronat, F.; Palau Salvador, CE. (2021). Design and Development of an AIoT Architecture for Introducing a Vessel ETA Cognitive Service in a Legacy Port Management Solution. Sensors. 21(23):1-15. https://doi.org/10.3390/s21238133115212

    Blood flow response to orthostatic challenge identifies signatures of the failure of static cerebral autoregulation in patients with cerebrovascular disease

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    Autorregulació cerebral; Malaltia cerebrovascular; Òptica difusaAutorregulación cerebral; Enfermedad cerebrovascular; Óptica difusaCerebral autoregulation; Cerebrovascular disease; Diffuse opticsBackground The cortical microvascular cerebral blood flow response (CBF) to different changes in head-of-bed (HOB) position has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS) technique. However, the relationship between these relative ΔCBF changes and associated systemic blood pressure changes has not been studied, even though blood pressure is a major driver of cerebral blood flow. Methods Transcranial DCS data from four studies measuring bilateral frontal microvascular cerebral blood flow in healthy controls (n = 15), patients with asymptomatic severe internal carotid artery stenosis (ICA, n = 27), and patients with acute ischemic stroke (AIS, n = 72) were aggregated. DCS-measured CBF was measured in response to a short head-of-bed (HOB) position manipulation protocol (supine/elevated/supine, 5 min at each position). In a sub-group (AIS, n = 26; ICA, n = 14; control, n = 15), mean arterial pressure (MAP) was measured dynamically during the protocol. Results After elevated positioning, DCS CBF returned to baseline supine values in controls (p = 0.890) but not in patients with AIS (9.6% [6.0,13.3], mean 95% CI, p < 0.001) or ICA stenosis (8.6% [3.1,14.0], p = 0.003)). MAP in AIS patients did not return to baseline values (2.6 mmHg [0.5, 4.7], p = 0.018), but in ICA stenosis patients and controls did. Instead ipsilesional but not contralesional CBF was correlated with MAP (AIS 6.0%/mmHg [− 2.4,14.3], p = 0.038; ICA stenosis 11.0%/mmHg [2.4,19.5], p < 0.001). Conclusions The observed associations between ipsilateral CBF and MAP suggest that short HOB position changes may elicit deficits in cerebral autoregulation in cerebrovascular disorders. Additional research is required to further characterize this phenomenon.The funders did not have any role in study design, execution and data interpretation. This work was funded by Redes Temáticas de Investigación Cooperativa (RETICS-INVICTUS RD012/0014 and RD16/0019/0010), Fundació CELLEX Barcelona, Ministerio de Economía y Competitividad/FEDER (PHOTODEMENTIA, PHOTOMETABO, DPI2015–64358-C2–1-R, PRE2018-085082), Instituto de Salud Carlos III/FEDER (FIS PI09/0557, MEDPHOTAGE, DTS16/00087), the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0522), the Obra Social “la Caixa” Foundation (LlumMedBcn), Institució “Centres de Recerca de Catalunya”, “Agència de Gestió d’Ajuts Universitaris i de Recerca”-Generalitat (2017SGR-1380), LASERLAB-EUROPE IV (EU-H2020 654148), Whitaker International Program of the Institute for International Education, T32 HL007954 Multidisciplinary training in cardiovascular biology, Marie Curie initial training network (OILTEBIA 317526), Marie Sklowdowska-Curie-COFUND (H2020, ICFOstepstone 2, 71329), “Fundació La Marató TV3” (201709.30, 201709.31), São Paulo Research Foundation (FAPESP) through 2012/02500–8 and National Institutes of Health (R01-NS060653, K24-NS058386, R24-HD050836, P41-EB015893, DP2-HD101400, U54-HD086984)

    Blood flow response to orthostatic challenge identifies signatures of the failure of static cerebral autoregulation in patients with cerebrovascular disease

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    Background: The cortical microvascular cerebral blood flow response (CBF) to different changes in head-of-bed (HOB) position has been shown to be altered in acute ischemic stroke (AIS) by diffuse correlation spectroscopy (DCS) technique. However, the relationship between these relative ¿CBF changes and associated systemic blood pressure changes has not been studied, even though blood pressure is a major driver of cerebral blood flow. Methods: Transcranial DCS data from four studies measuring bilateral frontal microvascular cerebral blood flow in healthy controls (n = 15), patients with asymptomatic severe internal carotid artery stenosis (ICA, n = 27), and patients with acute ischemic stroke (AIS, n = 72) were aggregated. DCS-measured CBF was measured in response to a short head-of-bed (HOB) position manipulation protocol (supine/elevated/supine, 5 min at each position). In a sub-group (AIS, n = 26; ICA, n = 14; control, n = 15), mean arterial pressure (MAP) was measured dynamically during the protocol. Results: After elevated positioning, DCS CBF returned to baseline supine values in controls (p = 0.890) but not in patients with AIS (9.6% [6.0,13.3], mean 95% CI, p < 0.001) or ICA stenosis (8.6% [3.1,14.0], p = 0.003)). MAP in AIS patients did not return to baseline values (2.6 mmHg [0.5, 4.7], p = 0.018), but in ICA stenosis patients and controls did. Instead ipsilesional but not contralesional CBF was correlated with MAP (AIS 6.0%/mmHg [- 2.4,14.3], p = 0.038; ICA stenosis 11.0%/mmHg [2.4,19.5], p < 0.001). Conclusions: The observed associations between ipsilateral CBF and MAP suggest that short HOB position changes may elicit deficits in cerebral autoregulation in cerebrovascular disorders. Additional research is required to further characterize this phenomenon.Peer ReviewedPostprint (published version

    Chitinase 3-like 1 is neurotoxic in primary cultured neurons

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    Chitinase 3-like 1 (CHI3L1) is known to play a role as prognostic biomarker in the early stages of multiple sclerosis (MS), and patients with high cerebrospinal fluid CHI3L1 levels have an increased risk for the development of neurological disability. Here, we investigated its potential neurotoxic effect by adding recombinant CHI3L1 in vitro to primary cultures of mouse cortical neurons and evaluating both neuronal functionality and survival by immunofluorescence. CHI3L1 induced a significant neurite length retraction after 24 and 48 hours of exposure and significantly reduced neuronal survival at 48 hours. The cytotoxic effect of CHI3L1 was neuron-specific and was not observed in mouse immune or other central nervous system cells. These results point to a selective neurotoxic effect of CHI3L1 in vitro and suggest a potential role of CHI3L1 as therapeutic target in MS patients

    Upward Mobility or Spurious Mobility?. An Analysis of Social Mobility’s Trajectories. Argentina 2007-2008

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    En este artículo ponemos en relación dos campos de estudio de las ciencias sociales: el de la movilidad social y el del mercado de trabajo. Complementamos el análisis de la relación origen/destino de clase con el de las condiciones deinserción en el mercado de trabajo, desde un enfoque metodológico cuantitativo. A su vez, cuestionamos la mirada funcionalista de la movilidad social que asimila movilidad con igualdad y reproducción con desigualdad, especificando la forma que asumen las trayectorias de movilidad. Para el caso argentino, en los años 2007-2008, se ha observado que una parte importante de la población ha mejorado su posición en relación al mercado de trabajo, aunque en términos de clase reproduzca su posición de origen.In this paper we relate two fields of study in social sciences: social mobility and labour market. We complement the analysis of class origin/ destination relationship with the analysis of the conditions of participation in the labour market. Thus, we question the view of the functionalist approach of social mobility, which assimilates mobility with equality and reproduction with inequality. For the Argentine case, in the years 2007-2008, it has been observed that a significant portion of the population has been improving their labor market position, although, in terms of class, they reproduces their origin position.Fil: Pla, Jésica Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigaciones "Gino Germani"; ArgentinaFil: Rodríguez de la Fuente, José Javier. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigaciones "Gino Germani"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernández Melián, María Clara. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigaciones "Gino Germani"; Argentin
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