Search results for "pattern"
showing 10 items of 4203 documents
An optimal population code for global motion estimation in local direction-selective cells
2021
AbstractNervous systems allocate computational resources to match stimulus statistics. However, the physical information that needs to be processed depends on the animal’s own behavior. For example, visual motion patterns induced by self-motion provide essential information for navigation. How behavioral constraints affect neural processing is not known. Here we show that, at the population level, local direction-selective T4/T5 neurons in Drosophila represent optic flow fields generated by self-motion, reminiscent to a population code in retinal ganglion cells in vertebrates. Whereas in vertebrates four different cell types encode different optic flow fields, the four uniformly tuned T4/T5…
Musicianship can be decoded from magnetic resonance images
2020
AbstractLearning induces structural changes in the brain. Especially repeated, long-term behaviors, such as extensive training of playing a musical instrument, are likely to produce characteristic features to brain structure. However, it is not clear to what extent such structural features can be extracted from magnetic resonance images of the brain. Here we show that it is possible to predict whether a person is a musician or a non-musician based on the thickness of the cerebral cortex measured at 148 brain regions en-compassing the whole cortex. Using a supervised machine-learning technique, we achieved a significant (κ = 0.321, p < 0.001) agreement between the actual and predicted par…
Rhythm pattern discrimination by primary school students
2020
Ascertaining the most effective modes of presenting rhythmic information to students is extremely important in order to facilitate rhythm training. This study examines the effects of different bimodal presentations of rhythmic information on the discrimination of rhythm patterns by primary school students. A 2 × 2 factorial design was conducted with two variables – audiovisual and audio-textual – each using two levels (static and dynamic). Four experimental conditions were designed: (1) static audiovisual, (2) dynamic audiovisual, (3) static audio-textual and (4) dynamic audio-textual. Data were collected by administering a rhythmic discrimination test to intact classes in second grade ( N…
Optimizing Query Perturbations to Enhance Shape Retrieval
2020
3D Shape retrieval algorithms use shape descriptors to identify shapes in a database that are the most similar to a given key shape, called the query. Many shape descriptors are known but none is perfect. Therefore, the common approach in building 3D Shape retrieval tools is to combine several descriptors with some fusion rule. This article proposes an orthogonal approach. The query is improved with a Genetic Algorithm. The latter makes evolve a population of perturbed copies of the query, called clones. The best clone is the closest to its closest shapes in the database, for a given shape descriptor. Experimental results show that improving the query also improves the precision and complet…
Dynamic Functional Connectivity Captures Individuals’ Unique Brain Signatures
2020
Recent neuroimaging evidence suggest that there exists a unique individual-specific functional connectivity (FC) pattern consistent across tasks. The objective of our study is to utilize FC patterns to identify an individual using a supervised machine learning approach. To this end, we use two previously published data sets that comprises resting-state and task-based fMRI responses. We use static FC measures as input to a linear classifier to evaluate its performance. We additionally extend this analysis to capture dynamic FC using two approaches: the common sliding window approach and the more recent phase synchrony-based measure. We found that the classification models using dynamic FC pa…
Reverse-safe data structures for text indexing
2021
We introduce the notion of reverse-safe data structures. These are data structures that prevent the reconstruction of the data they encode (i.e., they cannot be easily reversed). A data structure D is called z-reverse-safe when there exist at least z datasets with the same set of answers as the ones stored by D. The main challenge is to ensure that D stores as many answers to useful queries as possible, is constructed efficiently, and has size close to the size of the original dataset it encodes. Given a text of length n and an integer z, we propose an algorithm which constructs a z-reverse-safe data structure that has size O(n) and answers pattern matching queries of length at most d optim…
An Efficient Cooperative Smearing Technique for Degraded Historical Documents Images Segmentation
2020
Segmentation is one of the critical steps in historical document image analysis systems that determines the quality of the search, understanding, recognition and interpretation processes. It allows isolating the objects to be considered and separating the regions of interest (paragraphs, lines, words and characters) from other entities (figures, graphs, tables, etc.). This stage follows the thresholding, which aims to improve the quality of the document and to extract its background from its foreground, also for detecting and correcting the skew that leads to redress the document. Here, a hybrid method is proposed in order to locate words and characters in both handwritten and printed docu…
Typical symptom change patterns and their predictors in patients with social anxiety disorder: A latent class analysis
2020
Abstract Objectives The use of trajectories and analysis of change patterns is a promising way toward better differentiation of subgroups in psychotherapy studies. Research on change patterns in social anxiety disorder (SAD) are still rare, although SAD is one of the most common mental disorders. In a secondary analysis of data from the SOPHO-NET-trial (ISRCTN53517394) this study aimed to investigate change patterns and their predictors in a sample of SAD patients. Methods Patients with SAD (N = 357) were randomly assigned to cognitive-behavioral or psychodynamic therapy. The Liebowitz Social Anxiety Scale (LSAS) was assessed at 1st session (pre), 8th session, 15th session and at the end of…
Nonlinear femtosecond pulse propagation in an all-solid photonic bandgap fiber
2009
Nonlinear femtosecond pulse propagation in an all-solid photonic bandgap fiber is experimentally and numerically investigated. Guiding light in such fiber occurs via two mechanisms: photonic bandgap in the central silica core or total internal reflection in the germanium doped inclusions. By properly combining spectral filtering, dispersion tailoring and pump coupling into the fiber modes, we experimentally demonstrate efficient supercontinuum generation with controllable spectral bandwidth.
Online Intercultural Exchanges Through Digital Storytelling
2017
This article focuses on the affordances of a digital storytelling project in developing students' language, digital and other skills: learning and innovation, creativity, critical thinking, problem solving, team working, and life and career skills. The project was undertaken by university English for Specific Purposes students and was conducted within an Online Intercultural Exchange between the Cyprus University of Technology and the University of Valencia. Its design was based on a Project-Based Learning (PBL) methodology. It incorporated active learning and multimodal resources and capabilities. The need for transforming language teaching pedagogies was borne in mind, as it is necessary …