Search results for "spatio-temporal"
showing 10 items of 119 documents
Spatio-Temporal Analysis of Infectious Diseases
2019
Epidemiological research on the pathogenesis, diagnosis, and treatment of infectious diseases is a broad field of study with renewed validity in the face of social changes and new threats [...]
Walking tourism in Malaga: a pilot survey to explore tourism behaviours with a GPS approach
2018
Walking tourism in urban destinations can be defined as a sequence of day visits and/or a sequence of walking tours. In this work, GPS tracking data on spatio-temporal behaviour of walking tourists in Malaga are reported as case study. Malaga is a booming tourist destination characterized by a city centre, particularly suitable for a pedestrian visit. From 22nd January to 19th March 2018 for a total period of 41 days, a survey was carried out with a specific protocol: 103 interviews were conducted and 101 GPS valid tracks were collected. Walking tourists were systematically sampled, starting from the population of all tourists staying in the surveying day at some selected hotels in the city…
Time-resolved classification of dog brain signals reveals early processing of faces, species and emotion
2020
Dogs process faces and emotional expressions much like humans, but the time windows important for face processing in dogs are largely unknown. By combining our non-invasive electroencephalography (EEG) protocol on dogs with machine-learning algorithms, we show category-specific dog brain responses to pictures of human and dog facial expressions, objects, and phase-scrambled faces. We trained a support vector machine classifier with spatiotemporal EEG data to discriminate between responses to pairs of images. The classification accuracy was highest for humans or dogs vs. scrambled images, with most informative time intervals of 100–140 ms and 240–280 ms. We also detected a response sensitive…
Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020
2020
8 páginas, 3 figuras
Minimum contrast for point processes' first-order intensity estimation
2023
In this paper, we exploit some theoretical results, from which we know the expected value of the K-function weighted by the true first-order intensity function of a point pattern. This theoretical result can serve as an estimation method for obtaining the parameter estimates of a specific model, assumed for the data. The only requirement is the knowledge of the first-order intensity function expression, completely avoiding writing the likelihood, which is often complex to deal with in point process models. We illustrate the method through simulation studies for spatio-temporal point processes.
Spatio-temporal cluster detection of chickenpox in Valencia, Spain in the period 2008-2012.
2015
Chickenpox is a highly contagious airborne disease caused by <em>Varicella zoster</em>, which affects nearly all non-immune children worldwide with an annual incidence estimated at 80-90 million cases. To analyze the spatiotemporal pattern of the chickenpox incidence in the city of Valencia, Spain two complementary statistical approaches were used. First, we evaluated the existence of clusters and spatio-temporal interaction; secondly, we used this information to find the locations of the spatio-temporal clusters via the space-time permutation model. The first method used detects any aggregation in our data but does not provide the spatial and temporal information. The second me…
Structuring factors of the spatio-temporal variability of macrozoobenthos assemblages in a southern Mediterranean lagoon: How useful for bioindicatio…
2017
International audience; The authors investigated the impact of the extension of the El Kantra Channel on the composition and structure of macrobenthic assemblages in Boughrara Lagoon (Gulf of Gabes, Tunisia along with the use of 4 biotic indices (AMBI, BENTIX, M-AMBI and TUBI). Thirteen stations were sampled seasonally in 2012–2013. Forty-one species were found in 2012–2013 not recorded in 2009–2010, including 20 species of polychaetes belonging to the trophic groups of deposit-feeders and carnivores which are expected to increase in areas disturbed by organic pollution. During the survey, we recorded a high fish mortality, essentially caused by the development of harmful algal blooms (HAB)…
Joint second-order parameter estimation for spatio-temporal log-Gaussian Cox processes
2018
We propose a new fitting method to estimate the set of second-order parameters for the class of homogeneous spatio-temporal log-Gaussian Cox point processes. With simulations, we show that the proposed minimum contrast procedure, based on the spatio-temporal pair correlation function, provides reliable estimates and we compare the results with the current available methods. Moreover, the proposed method can be used in the case of both separable and non-separable parametric specifications of the correlation function of the underlying Gaussian Random Field. We describe earthquake sequences comparing several Cox model specifications.
Spatio-temporal Contrast Sensitivity in the Cardinal Directions of the Colour Space. A Review
2010
AbstractWe review the psychophysics of the spatio-temporal contrast sensitivity in the cardinal directions of the colour space and their correlation with those neural characteristics of the visual system that limit the ability to perform contrast detection or pattern-resolution tasks. We focus our attention particularly on the influence of luminance level, spatial extent and spatial location of the stimuli - factors that determine the characteristics of the physiological mechanisms underlying detection. Optical factors do obviously play a role, but we will refer to them only briefly. Contrast sensitivity measurements are often used in clinical practice as a method to detect, at their early …
Dynamic Changes in the Neurogenic Potential in the Ventricular–Subventricular Zone of Common Marmoset during Postnatal Brain Development
2020
AbstractEven after birth, neuronal production continues in the ventricular–subventricular zone (V–SVZ) and hippocampus in many mammals. The immature new neurons (“neuroblasts”) migrate and then mature at their final destination. In humans, neuroblast production and migration toward the neocortex and the olfactory bulb (OB) occur actively only for a few months after birth and then sharply decline with age. However, the precise spatiotemporal profiles and fates of postnatally born neurons remain unclear due to methodological limitations. We previously found that common marmosets, small nonhuman primates, share many features of V–SVZ organization with humans. Here, using marmosets injected wit…