117,309 research outputs found
Extended Granger causality: A new tool to identify the structure of physiological networks
No full textGranger causality (GC) is a very popular tool for assessing the presence of directional interactions between two time series of a multivariate data set. In its original formulation, GC does not account for zero-lag correlations possibly existing between the observed time series. In the present study we compare the GC with a novel measure, termed extended GC (eGC), able to capture instantaneous causal relationships. We present a two-step procedure for the practical estimation of eGC based on first detecting the existence of zero-lag correlations, and then assigning them to one of the two possible causal directions using pairwise measures of non-Gaussianity. The proposed method was validated in a simulation study, showing that the estimation procedure based on the extended representation overcomes the limits of the classic computation of GC, correctly detecting the presence and direction of zero-lag interactions and providing a meaningful causal interpretation based on the eGC. Then, GC and eGC were computed on the physiological variability series of heart period (HP), mean arterial pressure (AP) and cerebral blood flow velocity (FV) in ten subjects with postural related syncope (PRS), during different epochs of an head-up tilt test protocol. We found that both measures reflect the baroreflex impairment and the loss of cerebral autoregulation during pre-syncope. Furthermore, eGC analysis suggests that fast, within-beat effects between AP and FV variability contribute substantially to the mutual regulation of these physiological variables, and may play an important role in the impairment of cerebrovascular regulation associated with PRS
Investigating cardiovascular and cerebrovascular variability in postural syncope by means of extended Granger causality
No full textThe patterns of Granger causality (GC) between heart period (HP), mean arterial pressure (AP) and cerebral blood flow velocity (FV) were investigated in ten subjects with postural related syncope (PRS). The classic GC measure based on vector autoregressive (VAR) modeling was compared with a novel extended GC (eGC) measure derived from VAR models incorporating instantaneous causal effects among the series. The analysis was performed in the supine and in the upright position during early (ET) and late (LT, close to presyncope) epochs of head-up tilt. Moving from ET to LT, both GC and eGC decreased from AP to HP, and increased from AP to FV, reflecting baroreflex impairment and loss of cerebral autoregulation. The statistical significance of these changes was better assessed using the eGC, thus suggesting the importance of including instantaneous effects in the causality analysis of cardiovascular and cerebrovascular variability during PRS. © 2014 IEEE
Quality evaluation of Medicago sativa materials belonging to the Italian ecotype “Romagnola”.
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Mutual information-based feature selection for low-cost BCIs based on motor imagery
No full textIn the present study a feature selection algorithm based on mutual information (MI) was applied to electro-encephalographic (EEG) data acquired during three different motor imagery tasks from two dataset: Dataset I from BCI Competition IV including full scalp recordings from four subjects, and new data recorded from three subjects using the popular low-cost Emotiv EPOC EEG headset. The aim was to evaluate optimal channels and band-power (BP) features for motor imagery tasks discrimination, in order to assess the feasibility of a portable low-cost motor imagery based Brain-Computer Interface (BCI) system. The minimal sub set of features most relevant to task description and less redundant to each other was determined, and the corresponding classification accuracy was assessed offline employing linear support vector machine (SVM) in a 10-fold cross validation scheme. The analysis was performed: (a) on the original full Dataset I from BCI competition IV, (b) on a restricted channels set from Dataset I corresponding to available Emotiv EPOC electrodes locations, and (c) on data recorded with the EPOC system. Results from (a) showed that an offline classification accuracy above 80% can be reached using only 5 features. Limiting the analysis to EPOC channels caused a decrease of classification accuracy, although it still remained above chance level, both for data from (b) and (c). A top accuracy of 70% was achieved using 2 optimal features. These results encourage further research towards the development of portable low cost motor imagery-based BCI systems
NZEF. Near zero energy fabric. Recupero dell'ex Manifattura Schiatti, Lentate sul Seveso (MB)
No full textLAUREA MAGISTRALEPreservare il patrimonio storico, artistico e architettonico del nostro paese è un passo fondamentale per tramandare nel tempo i ricordi, le emozioni e le sensazioni generate negli individui che hanno vissuto tali luoghi e rendere questo patrimonio energeticamente efficiente ci permette di preservare l’ambiente, consegnandolo più sano e vivibile alle generazioni future.
L’ “Ex Manifattura Schiatti” di Lentate Sul Seveso era una realtà storica consolidata conosciuta in tutta la Brianza, fabbrica di tessuti di lusso, creativi e innovativi con il “Jacquard”, all’interno della quale numerosi abitanti di Lentate hanno lavorato, in una quotidianità durata più di cento anni. Situata al limite del centro storico, ne fa attualmente parte collocandosi al centro del comune; ha il pregio di essere sorta in un luogo che ad aggi risulta ben servito da attività e servizi in genere; numerosi sono anche le linee di traporto pubblico che lambiscono l’area, rendendola di fatto un sito che si presta a riprendere vita e a diventare la nuova centralità del paese: un muro anonimo che chiede rivincita, chiede di tornare ad essere il cuore pulsante di Lentate.
I manufatti industriali si sono discretamente conservati durante gli anni di abbandono della fabbrica: ne sono un esempio la palazzina che ospitava gli uffici e i locali dei disegnatori oppure le strutture che ospitavano la produzione dei tessuti.
Il progetto di recupero industriale mantiene il più possibile le tracce del preesistente, mirando a mantenere la memoria del luogo in cui ci troviamo dando un valore aggiunto al recupero stesso. Recupero che ha avuto come tema principale quello della riqualificazione energetica degli edifici esistenti e la progettazione di edifici a “energia quasi zero” per quelli di nuova costruzione, andando ad insediare funzioni, oltre alla residenziale, che potessero mantenere viva e vibrante nel tempo un’area centrale e ricca di storia quale la Schiatti è: una palestra e una piscina, un bar, un’edicola, un ristorante, un laboratorio dolciario, uffici per professionisti e aziende, un Auditorim per la banda del paese e un “Hub di Moda” che rinnova la creatività e l’innovazione che la Schiatti porta nel suo nome e nella sua memoria, alla quale viene dedicata un’apposita sala museale.To preserve the historical, artistic and architectural heritage of our country is a key step to pass on the memories, emotions and feelings generated in individuals who have lived in such places and make this heritage energetically efficient allows us to preserve the environment by delivering it Healthier and more liveable to future generations.
The "Ex Schiatti Manifattura" of Lentate Sul Seveso was a well-established historic reality known throughout Brianza, a luxury, creative and innovative fabric factory with "Jacquard", within which many Lentate inhabitants worked in A daily life lasting more than a hundred years. Located at the edge of the historic center, it is currently part of the city center; Has the advantage of being born in a place that is well served by activities and services in general; There are also numerous public transport lines lying around the area, making it in fact a site that lends itself to life and becomes the new centrality of the country: an anonymous wall asking for revenge, asks to return to being the pulsate heart of Lentate .
Industrial artifacts have been discreetly preserved during the factory's abandoned years. An example is the building that housed the designers' offices and premises or the structures that housed the fabric.
The industrial recovery project keeps track of the pre-existing trace as much as possible, aiming to keep the memory of the place where we are, giving added value to the recovery itself. Recovery that had as its main theme that of the energy upgrading of existing buildings and the design of "almost zero energy" buildings for newly built buildings, going to set up functions, in addition to residential, that could keep alive and vibrant over time a ' Central area rich in history such as the Schiatti is: a gym and swimming pool, a bar, a newsagent, a restaurant, a confectionery workshop, offices for professionals and companies, an Auditorim for the band of the country and a "Fashion Hub "Which renews the creativity and innovation that Schiatti brings in its name and memory, to which a dedicated museum hall is dedicated
Modeling Visual Impairments with Artificial Neural Networks: a Review
No full textWe present an approach to bridge the gap between the computational models of human vision and the clinical practice on visual impairments (VI). In a nutshell, we propose to connect advances in neuroscience and machine learning to study the impact of VI on key functional competencies and improve treatment strategies. We review related literature, with the goal of promoting the full exploitation of Artificial Neural Network (ANN) models in meeting the needs of visually impaired individuals and the operators working in the field of visual rehabilitation. We first summarize the existing types of visual issues, the key functional vision-related tasks, and the current methodologies used for the assessment of both. Second, we explore the ANNs best suitable to model visual issues and to predict their impact on functional vision-related tasks, at a behavioral (including performance and attention measures) and neural level. We provide guidelines to inform the future research about developing and deploying ANNs for clinical applications targeting individuals affected by VI
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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