651 research outputs found
A Binaural Neuromorphic Auditory Sensor for FPGA: A Spike Signal Processing Approach
This paper presents a new architecture, design
flow, and field-programmable gate array (FPGA) implementation
analysis of a neuromorphic binaural auditory sensor, designed
completely in the spike domain. Unlike digital cochleae that
decompose audio signals using classical digital signal processing
techniques, the model presented in this paper processes information
directly encoded as spikes using pulse frequency modulation
and provides a set of frequency-decomposed audio information
using an address-event representation interface. In this case,
a systematic approach to design led to a generic process for
building, tuning, and implementing audio frequency decomposers
with different features, facilitating synthesis with custom features.
This allows researchers to implement their own parameterized
neuromorphic auditory systems in a low-cost FPGA in order to
study the audio processing and learning activity that takes place
in the brain. In this paper, we present a 64-channel binaural
neuromorphic auditory system implemented in a Virtex-5 FPGA
using a commercial development board. The system was excited
with a diverse set of audio signals in order to analyze its response
and characterize its features. The neuromorphic auditory system
response times and frequencies are reported. The experimental
results of the proposed system implementation with 64-channel
stereo are: a frequency range between 9.6 Hz and 14.6 kHz
(adjustable), a maximum output event rate of 2.19 Mevents/s,
a power consumption of 29.7 mW, the slices requirements
of 11 141, and a system clock frequency of 27 MHz.Ministerio de Economía y Competitividad TEC2012-37868-C04-02Junta de Andalucía P12-TIC-130
Determination of organic pollutants in meconium and its relationship with fetal growth: case control study in Northwestern Spain
[Abstract] Objectives: Antenatal exposure to organic pollutants is a leading public health problem. Meconium is a unique matrix to perform prenatal studies because it enables us to retrospectively evaluate fetal exposure accumulated during the second and third trimester. The aim of the present study was to evaluate associations between organic pollutant levels in meconium and birth weight in NW Spain.
Methods: In this study, we quantify the concentrations of 50 organic pollutants together with the total values of the most important chemical groups in meconium using gas chromatography coupled to tandem mass spectrometry.
Results: Organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers were detected with the highest levels in meconium from small for gestational age newborns. It was estimated that several congeners were statistically significant (p<0.05). However, organophosphorus pesticides attained higher concentrations in newborns with an appropriate weight.
Conclusions: The occurrence of transplacental transfer can be confirmed. Prenatal exposure to organic pollutants was associated with a decrease in birth weight and, therefore, organic pollutants could have an impact on fetal growth. Nevertheless, these results need validation in larger sample sized studies
Actualización de material docente basado en Jupyter Notebook para su uso dentro del Plan de Internacionalización
La iniciativa de este proyecto viene justificada a la vista del gran interés generado por algunos de los materiales docentes diseñados por nuestro grupo en anteriores proyectos, en los que se vienen desarrollando diferentes herramientas docentes basadas en el uso de Jupyter Notebooks. A la vista del impacto generado, y teniendo en cuenta que la evolución del proyecto Jupyter, así como las aplicaciones de distintas herramientas asociadas a Jupyter Notebook, es continua, nos planteamos como objetivo principal del presente proyecto la actualización y la puesta a disposición en inglés de nuestra producción de los últimos años
Review of Technological Challenges in Personalised Medicine and Early Diagnosis of Neurodegenerative Disorders
Neurodegenerative disorders are characterised by progressive neuron loss in specific brain areas. The most common are Alzheimer’s disease and Parkinson’s disease; in both cases, diagnosis is based on clinical tests with limited capability to discriminate between similar neurodegenerative disorders and detect the early stages of the disease. It is common that by the time a patient is diagnosed with the disease, the level of neurodegeneration is already severe. Thus, it is critical to find new diagnostic methods that allow earlier and more accurate disease detection. This study reviews the methods available for the clinical diagnosis of neurodegenerative diseases and potentially interesting new technologies. Neuroimaging techniques are the most widely used in clinical practice, and new techniques such as magnetic resonance imaging (MRI) and positron emission tomography (PET) have significantly improved the diagnosis quality. Identifying biomarkers in peripheral samples such as blood or cerebrospinal fluid is a major focus of the current research on neurodegenerative diseases. The discovery of good markers could allow preventive screening to identify early or asymptomatic stages of the neurodegenerative process. These methods, in combination with artificial intelligence, could contribute to the generation of predictive models that will help clinicians in the early diagnosis, stratification, and prognostic assessment of patients, leading to improvements in patient treatment and quality of life.This publication is part of the Grant PID2 021-126434OB-I00 funded by MCIN/AEI/10.13039/501100011033 and ERDF A way of making Europe. It has also been funded by the Basque Government (IT1706-22 and PUE21-03) and the University of the Basque Country, UPV/EHU (GIU19/092 and COLAB20/07). This research was conducted in the scope of the Transborder Joint Laboratory (LTC) “non-motor Comorbidities in Parkinson’s Disease (CoMorPD)”
A Zebrafish Model of Neurotoxicity by Binge-Like Methamphetamine Exposure
Hyperthermia is a common confounding factor for assessing the neurotoxic effects of methamphetamine (METH) in mammalian models. The development of new models of methamphetamine neurotoxicity using vertebrate poikilothermic animals should allow to overcome this problem. The aim of the present study was to develop a zebrafish model of neurotoxicity by binge-like methamphetamine exposure. After an initial testing, zebrafish was exposed to 40 mg/L of METH for 48h, and the effects on the brain monoaminergic profile, locomotor, anxiety-like and social behaviors as well as on the expression of key genes of the catecholaminergic system were determined. A concentration- and time-dependent decrease in the brain levels of dopamine (DA), norepinephrine (NE) and serotonin (5-HT) was found in METH-exposed fish. A significant hyperactivity was found during the first hour of exposure followed 3h after by a positive geotaxis and negative scototaxis in the novel tank and in the light/dark paradigm, respectively. Moreover, the behavioral phenotype in the treated fish was consistent with social isolation. At transcriptional level, th1 and slc18a2 (vmat2) exhibited a significant increase after 3h of exposure, whereas the expression of gfap, a marker of astroglial response to neuronal injury, was strongly increased after 48h exposure. However, no evidences of oxidative stress were found in the brain of the treated fish. Altogether, this study demonstrates the suitability of the adult zebrafish as a model of METH-induced neurotoxicity and provides more information about the biochemical and behavioral consequences of METH abuse
The Influence of Stud Characteristics of Football Boots Regarding Player Injuries
Background: the main aim of this study was to analyze the relationship between sole pattern parameters of football boots with the frequency of injuries that occur in semiprofessional and amateur footballers. Methods: The study sample was composed of 77 male football players. All were at least 18 years old, played at least 10 h per week, gave signed informed consent to take part and properly completed the Visual Analogue Scale. This study analysed data from each player’s medical history, including age, injuries, years of practice, field type and surface condition information. Results: The visual analogic score in semiprofessional players was higher (2.05 ± 2.43) than in amateur players (1.00 ± 1.1). A total of 141 lesions were collected, equivalent to 1.81 injuries for each football player studied (n = 77). The result of the ROC curve indicated that the player’s years of practice could predict significantly (p < 0.05) the presence of lower limb injuries, with an area under the curve of 0.714. Conclusions: This study described the predictive capacity of sole pattern characteristics concerning lower limb injuries in amateur and semiprofessional footballers. Football boot variables associated with the number of studs were associated with foot and ankle overload injuries.Partial funding for open access charge: Universidad de Málag
Floquet engineering of Dirac cones on the surface of a topological insulator
We propose to Floquet engineer Dirac cones at the surface of a three-dimensional topological insulator. We show that a large tunability of the Fermi velocity can be achieved as a function of the polarization, direction, and amplitude of the driving field. Using this external control, the Dirac cones in the quasienergy spectrum may become elliptic or massive, in accordance with experimental evidence. These results help us to understand the interplay of surface states and external ac driving fields in topological insulators. In our work we use the full Hamiltonian for the three-dimensional system instead of effective surface Hamiltonians, which are usually considered in the literature. Our findings show that the Dirac cones in the quasienergy spectrum remain robust even in the presence of bulk states, and therefore, they validate the usage of effective surface Hamiltonians to explore the properties of Floquet-driven topological boundaries. Furthermore, our model allows us to introduce out-of-plane field configurations which cannot be accounted for by effective surface Hamiltonians
Easing the questioning of semantic biomedical data
Researchers have been using semantic technologies
as essential tools to structure knowledge. This is particularly
relevant in the biomedical domain, where large dataset are
continuously generated. Semantic technologies offer the ability
to describe data and to map and linking distributed repositories,
creating a network where the searching interface is a single entry
point. However, the increasing number of semantic data repositories
that are publicly available is creating new challenges related
to its exploration. Despite being human and machine-readable,
these technologies are much more challenging for end-users.
Querying services usually require mastering formal languages
and that knowledge is beyond the typical user’s expertise, being
a critical issue in adopting semantic web information systems. In
particular, the questioning of biomedical data presents specific
challenges for which there are still no mature proposals for
production environments. This paper presents a solution to
query biomedical semantic databases using natural language. The
system is at the intersection between semantic parsing and the
use of templates. It makes it possible to extract information in a
friendly way for users who are not experts in semantic queries.FCT - Portuguese Foundation for Science and Technology
supports Arnaldo Pereira (Ph.D. Grant PD/BD/142877/2018).info:eu-repo/semantics/publishedVersio
Evolution of the corpus luteum volume determined ultrasonographically and its relation to the plasma progesterone concentration after artificial insemination in pregnant and non-pregnant dairy cows
P. 183–188The aim of this study was to assess the relationship of the evolution of the corpus luteum (CL) volume that was determined ultrasonographically with the pregnancy status in lactating dairy cows during early pregnancy. Ultrasound examinations were carried out on 76 cows following artificial insemination (AI). Plasma concentrations of progesterone were determined from blood samples collected at each ultrasound examination. Conception was confirmed by ultrasonography on day 30 after AI. Around day 14 post-insemination (p.i.), the CL volume tended to decrease in pregnant and non-pregnant cows, and, after day 19 p.i., both groups differed significantly, indicating the luteal regression in non-pregnant cows. Reaching signification on day 20. The diminution in CL volume was also reflected in the plasma progesterone concentration. However, the patterns of CL volume, estimated by ultrasonography, differed more evidently and earlier between both groups (around 1 week p.i., at day 9 p.i. P < 0.05, whereas progesterone started to differ around 2 weeks p.i., at day 14 p.i, P < 0.05). These results indicate that the estimation of the CL volume by ultrasonography could be useful for assessing the presence of a functional CL.S
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