The role of peripheral vision in implicit contextual cuing

Implicit contextual cuing refers to the ability to learn the association between contextual information of our environment and a specific target, which can be used to guide attention during visual search. It was recently suggested that the storage of a snapshot image of the local context of a target underlies implicit contextual cuing. To make such a snapshot, it is necessary to use peripheral vision. In order to test whether peripheral vision can underlie implicit contextual cuing, we used a covert visual search task, in which participants were required to indicate the orientation of a target stimulus while foveating a fixation cross. The response times were shorter when the configuration of the stimuli was repeated than when the configuration was new. Importantly, this effect was still found after 10 days, indicating that peripherally perceived spatial context information can be stored in memory for long periods of time. These results indicate that peripheral vision can be used to make a snapshot of the local context of a targetThis research was supported by a grant from the BIAL Foundation (No. 73/06) and the FCT (SFRH/BPD/22088/2005

Self-mediated exploration in artificial intelligence inspired by cognitive psychology

Exploration of the physical environment is an indispensable precursor to data acquisition and enables knowledge generation via analytical or direct trialing. Artificial Intelligence lacks the exploratory capabilities of even the most underdeveloped organisms, hindering its autonomy and adaptability. Supported by cognitive psychology, this works links human behavior and artificial agents to endorse self-development. In accordance with reported data, paradigms of epistemic and achievement emotion are embedded to machine-learning methodology contingent on their impact when decision making. A study is subsequently designed to mirror previous human trials, which artificial agents are made to undergo repeatedly towards convergence. Results demonstrate causality, learned by the vast majority of agents, between their internal states and exploration to match those reported for human counterparts. The ramifications of these findings are pondered for both research into human cognition and betterment of artificial intelligence.Comment: 21 pages, 5 figures, journa

Acceleration patterns in the perception of biological motion

A lot of natural stimuli are characterized by acceleration patterns. However, available studies are inconclusive about the importance of these patterns on visual perception. Empirical findings seems to both sustain that acceleration patterns might have, or might have not, a significant role on visual perception [Runeson, 1974 Psychological Research 37 3-23; McIntyre et al, 2001 Nature Neuroscience 4(7) 693-694]. In a recent study Chang and Troje [2009 Journal of Vision 9(1) 19-17] stressed the role of acceleration patterns for the perception of biological motion. Nevertheless, we have a limited understanding about the implications of these patterns for translational stimuli. The present study aimed to investigate how acceleration patterns influence the perception of biological translational motion. We manipulated the velocity of the translational component (maintaining spatial characteristics). This allowed us to create a continuum of stimuli that ranged from natural motion to constant velocity. When two stimuli are presented simultaneously participants are asked to choose which appears more natural. Data shows that subjects choose the stimulus closest to the natural motion—biological motion. Results reveal a great accuracy in detecting the stimulus closest to biological motion, which suggests that acceleration patterns are important in the perception of translational biological motion.Fundação para a Ciência e a Tecnologia (FCT

Microaneurysms detection using a novel neighborhood analysis

The earliest sign of the diabetic retinopathy is the appearance of small red dots in retinal fundus images, designated by microaneurysms. In this paper a scale-space based method is proposed for the microaneurysms detection. Initially, the method performs a segmentation of the retinal vasculature and defines a global set of microaneurysms candidates, using both coarser and finer scales. Using the finer scales, a set of microaneurysms candidates are analysed in terms of shape and size. Then, a set of gaussian-shaped matched filters are used to reduce the number of false microaneurysms candidates. Each candidate is labeled as a true microaneurysm using a new neighborhood analysis method. The proposed algorithm was tested with the training Retinopathy Online Challenge (ROC) dataset, revealing a 47% Sensitivity with an average number of 37.9 false positives per image

Efficacy of Aliskiren/Hydrochlorothiazide Combination for the Treatment of Hypertension: A Meta-Analytical Approach

Background: Single-pill combinations of aliskiren/hydrochlorothiazide have recently been approved by the European Medicines Agency for the treatment of hypertension. Objective: This study aimed to assess the antihypertensive efficacy of aliskiren/hydrochlorothiazide combination in reducing systolic and diastolic blood pressure in hypertensive patients. Methods: A search in International Pharmaceutical Abstracts, MEDLINE, The Cochrane Library and ISI Web of Knowledge was performed from 2000 to November 2009, to identify randomized, double-blind, clinical trials using aliskiren/hydrochlorothiazide for the treatment of hypertension. Studies were included if they evaluated the antihypertensive efficacy of aliskiren/hydrochlorothiazide in patients with mild or moderate essential hypertension and age 18 years. The meta-analytical approach calculated the weighted average reductions of systolic and diastolic blood pressure for each daily dosage combination. Results: We included 5 clinical trials testing several combinations of aliskiren/hydrochlorothiazide and containing data on 5448 patients. In all studies blood pressure was assessed at inclusion (baseline) and after 8 weeks of therapy. Blood pressure reductions and control rates were significantly (p < 0.05) higher with the aliskiren/hydrochlorothiazide combinations than with placebo and the same doses of aliskiren or hydrochlorothiazide alone. The weighted mean reductions (mm Hg) from baseline of systolic and diastolic blood pressure for each aliskiren/hydrochlorothiazide combination were: -15.8/- 10.3 (150/25 mg); -15.9/-11.8 (300/12.5 mg); -16.9/-11.6 (300/25 mg). Blood pressure control rates (%) for the above combinations were, at least, respectively: 43.8, 50.1 and 51.9. Conclusions: Aliskiren/hydrochlorothiazide provided clinically significant additional blood pressure reductions and improved blood pressure control rates over aliskiren or hydrochlorothiazide monotherapy.We thank the Fundação para a Ciência e a Tecnologia (FCT) for supporting the fellowship grant SFRH/BD/36756/ 2007 to Manuel Morgado

Enzymatic time-temperature integrator device for chromatic quality check of Cova da Beira’s cherry (Portugal)

Cherry is a fruit widely appreciated by consumers in general. In Portugal, within the Beira Interior region, and particularly, Cova da Beira, is the most representative area with a production of more than 50% of the national production. The peculiar characteristics of cherries, such as color, firmness, palate, among others, increase the demand for this fruit, which can only be commercialized during a short period. Its high perishability interferes with the shelf life and consequently generates undesirable changes in the cherry flow chain. In order to ensure food quality and safety and prevent food waste, a time-temperature integrator (TTI) device to monitor the quality of the cherry in real time is proposed. This device suffers a chromatic change with the temperature variation over time. For the specific case of the cherry, the kinetic parameters for thermal inactivation are determined which leads to the proposal of an enzymatic-type TTI, where the degradation of the phenolic compounds occurs, which are substrates of the polyphenol oxidase enzyme, whose hydroxylation reaction of a monophenol in o-diphenol leads to the oxidation in o-Quinone. This device aims to help retailers to decide when and where to sell the food items taking into account the remaining shelf life, as well as support the decision of purchase by the consumer predicting through a chromatic and expedite stamp the food quality and safetyinfo:eu-repo/semantics/publishedVersio

The Ideal Profile of the Telemedicine User– Experience From Portugal

Over the last few years, all over the world, telemedicine has been gaining momentum, and became more accepted by both health workers and patients as an essential tool in medicine. There have been a considerable number of studies whose results show the benefits of telemedicine programmes, not only in cost reduction and decreasing the number of exacerbations and hospital admissions, but also in improving health outcomes, with the patients having a better understanding of their illness and how they can manage it. This study is based on a tele monitoring programme being carried out in the village of Sabugueiro in Portugal. This village is one the first “Smart mountain villages” in the world, and besides having the concept of Internet of Things” applied to its infrastructure, it also has a tele-monitoring component, where blood pressure, blood glucose levels and weight of part of the population are monitored, in both healthy and unhealthy individuals. Abnormal changes of these parameters are very prevalent in our society, being responsible for a great deal of the national health system expenditure and being an important risk factor for cardiovascular events, the number one cause of death in Portugal. Therefore, their correct management is of vital importance in order to reduce costs, morbidity and mortality related to these events. However, this programmes results fell short of what was desired, with low compliance by the patients, who did not make the recommended number of measurements. The main goal of this study was to understand what can improve the compliance of a telemonitoring patient, what they find the most difficult to cope with, and when this kind of programme is useful

Anterior/Posterior Competitive Deactivation/Activation Dichotomy in the Human Hippocampus as Revealed by a 3D Navigation Task

Anterior/posterior long axis specialization is thought to underlie the organization of the hippocampus. However it remains unclear whether antagonistic mechanisms differentially modulate processing of spatial information within the hippocampus. We used fMRI and a virtual reality 3D paradigm to study encoding and retrieval of spatial memory during active visuospatial navigation, requiring positional encoding and retrieval of object landmarks during the path. Both encoding and retrieval elicited BOLD activation of the posterior most portion of hippocampus, while concurrent deactivations (recently shown to reflect decreases in neural responses) were found in the most anterior regions. Encoding elicited stronger activity in the posterior right than the left hippocampus. The former structure also showed significantly stronger activity for allocentric vs. egocentric processing during retrieval. The anterior vs. posterior pattern mimics, from a functional point, although at much distinct temporal scales, the previous anatomical findings in London taxi drivers, whereby posterior enlargement was found at the cost of an anterior decrease, and the mirror symmetric findings observed in blind people, in whom the right anterior hippocampus was found to be larger, at the cost of a smaller posterior hippocampus, as compared with sighted people. In sum, we found a functional dichotomy whereby the anterior/posterior hippocampus shows antagonistic processing patterns for spatial encoding and retrieval of 3D spatial information. To our knowledge, this is the first study reporting such a dynamical pattern in a functional study, which suggests that differential modulation of neural responses within the human hippocampus reflects distinct roles in spatial memory processing