Proprioception, the sense of limb and body position, is required to produce accurate and precise movements. Proprioceptive sensory neurons transmit muscle length and tension information to the spinal cord. The function of excitatory neurons in the intermediate spinal cord, which receive this proprioceptive information, remains poorly understood. Using genetic labeling strategies and patch-clamp techniques in acute spinal cord preparations in mice, we set out to uncover how two sets of spinal neurons, Clarke's column (CC) and Atoh1-lineage neurons, respond to electrical activity and how their inputs are organized. Both sets of neurons are located in close proximity in laminae V-VII of the thoracolumbar spinal cord and have been described to receive proprioceptive signals. We find that a majority of CC neurons have a tonic-firing type and express a distinctive hyperpolarization-activated current (Ih). Atoh1-lineage neurons, which cluster into two spatially distinct populations, are mostly a fading-firing type and display similar electrophysiological properties to each other, possibly due to their common developmental lineage. Finally, we find that CC neurons respond to stimulation of lumbar dorsal roots, consistent with prior knowledge that CC neurons receive hindlimb proprioceptive information. In contrast, using a combination of electrical stimulation, optogenetic stimulation, and transsynaptic rabies virus tracing, we find that Atoh1-lineage neurons receive heterogeneous, predominantly local thoracic inputs that include parvalbumin-lineage sensory afferents and local interneuron presynaptic inputs. Altogether, we find that CC and Atoh1-lineage neurons have distinct membrane properties and sensory input organization, representing different subcircuit modes of proprioceptive information processing.
Proprioception , Spinal Cord , Animals , Proprioception/physiology , Spinal Cord/physiology , Spinal Cord/cytology , Basic Helix-Loop-Helix Transcription Factors/metabolism , Basic Helix-Loop-Helix Transcription Factors/genetics , Mice, Transgenic , Mice , Male , Female , Action Potentials/physiology , Sensory Receptor Cells/physiology , Patch-Clamp Techniques , Mice, Inbred C57BL , Thoracic Vertebrae
Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders characterized by persistent deficits in social communication and social interaction. Altered synaptogenesis and aberrant connectivity responsible for social behavior and communication have been reported in autism pathogenesis. Autism has a strong genetic and heritable component; however, environmental factors including toxins, pesticides, infection and in utero exposure to drugs such as VPA have also been implicated in ASD. Administration of VPA during pregnancy has been used as a rodent model to study pathophysiological mechanisms involved in ASD, and in this study, we used the mouse model of prenatal exposure to VPA to assess the effects on striatal and dorsal hippocampus function in adult mice. Alterations in repetitive behaviors and shift habits were observed in mice prenatally exposed to VPA. In particular, such mice presented a better performance in learned motor skills and cognitive deficits in Y-maze learning frequently associated with striatal and hippocampal function. These behavioral changes were associated with a decreased level of proteins involved in the formation and maintenance of excitatory synapses, such as Nlgn-1 and PSD-95. In conclusion, motor skill abilities, repetitive behaviors, and impaired flexibility to shift habits are associated with reduced striatal excitatory synaptic function in the adult mouse prenatally exposed to VPA.
Autism Spectrum Disorder , Autistic Disorder , Prenatal Exposure Delayed Effects , Pregnancy , Humans , Female , Mice , Animals , Valproic Acid/pharmacology , Prenatal Exposure Delayed Effects/chemically induced , Social Behavior , Disease Models, Animal , Behavior, Animal
Resumen Objetivo: identificar el grado de integración de características de calidad inherentes a las revistas digitales para valorar la forma en cómo están aprovechando las actuales herramientas que facilitan el acceso y uso de información científica. Metodología: se seleccionan las ocho características digitales de la metodología del Catálogo 2.0 de Latindex y se comprueba su presencia en los sitios web institucionales de 195 revistas académicas editadas en México. Resultados: Las características que presentan menor ocurrencia son los servicios de interactividad con las personas lectoras, el uso de más de un formato de edición para la consulta de los textos completos, así como el establecimiento de políticas de preservación digital, todas ellas con menos del 50% de cumplimiento. Del grupo estudiado, 127 revistas (65%) integraron entre cinco y ocho características en sus sitios web. Conclusiones: Se percibe que las revistas del estudio cumplen de manera diferente en la integración de los criterios de calidad digital; asimismo, se hace evidente que la mayoría no aprovechan a cabalidad las herramientas y servicios digitales disponibles en el gestor OJS, el cual es utilizado por casi la totalidad de las revistas analizadas. Se evidencia que aún hay trabajo por realizar para fomentar la integración de un mayor número de herramientas digitales, particularmente en las revistas que integran un mínimo de ellas y que sin embargo son denominadas digitales a la par de aquellas que presentan una mayor adaptación digital.
Abstract Objective: to identify the degree of integration of quality characteristics inherent to digital journals in order to assess how they are taking advantage of the current tools that facilitate the access and use of scientific information. Methodology: Eight digital characteristics of the Latindex Catalog 2.0 methodology were selected and their presence was verified in the institutional websites of 195 journals edited in Mexico. Results: Characteristics with a lesser degree of presence are: interactivity services with readers, use of more than one editing format for full text consultation, as well as the establishing of digital preservation policies, all of them with a compliance of less than 50%. Of the studied group, 127 journals (65%) integrated between five and eight characteristics on their websites. Conclusions: The integration of the eight quality criteria inherent to digital journals is differentially met by the studied publications. Likewise, it became clear that the digital tools and services available in the OJS manager are not being fully exploited by most of the analyzed journals. One of the most important findings is that there is necessary to promote the integration of a greater number of the characteristics specific to digital journals, particularly in those that remain in a very basic level and that nevertheless are referred as digital on par with other journals that have a higher digital adaptation.
Editorial Policies , Abstracting and Indexing , Periodical , Analog-Digital Conversion , Mexico
The high impact of air quality on environmental and human health justifies the increasing research activity regarding its measurement, modelling, forecasting and anomaly detection. Raw data offered by sensors usually makes the mentioned time series disciplines difficult. This is why the application of techniques to improve time series processing is a challenge. In this work, Singular Spectral Analysis (SSA) is applied to air quality analysis from real recorded data as part of the Help Responder research project. Authors evaluate the benefits of working with SSA processed data instead of raw data for modelling and estimation of the resulting time series. However, what is more relevant is the proposal to detect indoor air quality anomalies based on the analysis of the time derivative SSA signal when the time derivative of the noisy original data is useless. A dual methodology, evaluating level and dynamics of the SSA signal variation, contributes to identifying risk situations derived from air quality degradation.
Air Pollutants , Air Pollution, Indoor , Air Pollution , Air Pollutants/analysis , Air Pollution/analysis , Air Pollution, Indoor/analysis , Environmental Monitoring/methods , Forecasting , Humans
The development of unisexual flowers has been described in a large number of taxa, sampling the diversity of floral phenotypes and sexual systems observed in extant angiosperms, in studies focusing on floral ontogeny, on the evo-devo of unisexuality, or on the genetic and chromosomal bases of unisexuality. We review here such developmental studies, aiming at characterizing the diversity of ontogenic pathways leading to functionally unisexual flowers. In addition, we present for the first time and in a two-dimensional morphospace a quantitative description of the developmental rate of the sexual organs in functionally unisexual flowers, in a non-exhaustive sampling of angiosperms with contrasted floral morphologies. Eventually, recommendations are provided to help plant evo-devo researchers and botanists addressing macroevolutionary and ecological issues to more precisely select the taxa, the biological material, or the developmental stages to be investigated.
Proprioception, the sense of limb and body position, generates a map of the body that is essential for proper motor control, yet we know little about precisely how neurons in proprioceptive pathways are wired. Defining the anatomy of secondary neurons in the spinal cord that integrate and relay proprioceptive and potentially cutaneous information from the periphery to the cerebellum is fundamental to understanding how proprioceptive circuits function. Here, we define the unique anatomic trajectories of long-range direct and indirect spinocerebellar pathways as well as local intersegmental spinal circuits using genetic tools in both male and female mice. We find that Clarke's column neurons, a major contributor to the direct spinocerebellar pathway, has mossy fiber terminals that diversify extensively in the cerebellar cortex with axons terminating bilaterally, but with no significant axon collaterals within the spinal cord, medulla, or cerebellar nuclei. By contrast, we find that two of the indirect pathways, the spino-lateral reticular nucleus and spino-olivary pathways, are in part, derived from cervical Atoh1-lineage neurons, whereas thoracolumbar Atoh1-lineage neurons project mostly locally within the spinal cord. Notably, while cervical and thoracolumbar Atoh1-lineage neurons connect locally with motor neurons, no Clarke's column to motor neuron connections were detected. Together, we define anatomic differences between long-range direct, indirect, and local proprioceptive subcircuits that likely mediate different components of proprioceptive-motor behaviors.SIGNIFICANCE STATEMENT We define the anatomy of long-range direct and indirect spinocerebellar pathways as well as local spinal proprioceptive circuits. We observe that mossy fiber axon terminals of Clarke's column neurons diversify proprioceptive information across granule cells in multiple lobules on both ipsilateral and contralateral sides, sending no significant collaterals within the spinal cord, medulla, or cerebellar nuclei. Strikingly, we find that cervical spinal cord Atoh1-lineage neurons form mainly the indirect spino-lateral reticular nucleus and spino-olivary tracts and thoracolumbar Atoh1-lineage neurons project locally within the spinal cord, whereas only a few Atoh1-lineage neurons form a direct spinocerebellar tract.
Cerebellum/physiology , Nerve Net/physiology , Proprioception/physiology , Spinal Cord/physiology , Spinocerebellar Tracts/physiology , Animals , Animals, Newborn , Cerebellum/chemistry , Cerebellum/cytology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Nerve Net/chemistry , Nerve Net/cytology , Spinal Cord/chemistry , Spinal Cord/cytology , Spinocerebellar Tracts/chemistry , Spinocerebellar Tracts/cytology
Se exploran los efectos de variar el orden espacial de la disponibilidad de producción del agua sobre las trayectorias empleadas por el organismo y la ubicación espacio-temporal de sus res-puestas (introducción de cabeza al bebedero y de presión de palanca). Dos grupos de cuatro ra-tas fueron expuestos encámaras de condicionamiento ampliadas a condiciones en las que la disponibilidad de producción varió en tres palancas. Para el Grupo 1, en la Fase 1 la disponibi-lidad se limitó a una palanca, en la Fase 2 varió en orden secuencial en tres palancas. En la Fa-se 3, la disponibilidad varió aleatoriamente en tres palancas. El Grupo 2 fue expuesto a fases similares, pero en un orden inverso. Los resultados mostraron que las ratas reprodujeron los parámetros espaciales programados para la producción del agua. Se observó un efecto de arras-tre consistente entre ratas, lo que se interpretó como desligamiento funcional. (AU)
We explore the effects of varying the spatial order of water production availability on the tra-jectories employed by the organism and the spatio-temporal location of its responses (head in-troduction into the liquid dispenser and lever pressure). Two groupsof four rats were exposed in expanded conditioning chambers to conditions in which production availability varied by three levers. For Group 1, in Phase 1 availability was limited to one lever, in Phase 2 it varied in sequential order across three levers.In Phase 3, availability varied randomly across three levers. Group 2 was exposed to similar phases but in a reverse order. The results showed that the rats reproduced the spatial parameters programmed for water production. A consistent carryover effect was observed between rats, which was interpreted as functional detachment. (AU)
Mice , Spatial Behavior , Behavioral Research/methods
Motor neurons (MNs) innervating the digit muscles of the intrinsic hand (IH) and intrinsic foot (IF) control fine motor movements. The ability to reproducibly label specifically IH and IF MNs in mice would be a beneficial tool for studies focused on fine motor control. To this end, we find that a CRE knock-in mouse line of Atoh1, a developmentally expressed basic helix-loop-helix (bHLH) transcription factor, reliably expresses CRE-dependent reporter genes in â¼60% of the IH and IF MNs. We determine that CRE-dependent expression in IH and IF MNs is ectopic because an Atoh1 mouse line driving FLPo recombinase does not label these MNs although other Atoh1-lineage neurons in the intermediate spinal cord are reliably identified. Furthermore, the CRE-dependent reporter expression is enriched in the IH and IF MN pools with much sparser labeling of other limb-innervating MN pools such as the tibialis anterior (TA), gastrocnemius (GS), quadricep (Q), and adductor (Ad). Lastly, we find that ectopic reporter expression begins postnatally and labels a mixture of α and γ-MNs. Altogether, the Atoh1 CRE knock-in mouse strain might be a useful tool to explore the function and connectivity of MNs involved in fine motor control when combined with other genetic or viral strategies that can restrict labeling specifically to the IH and IF MNs. Accordingly, we provide an example of sparse labeling of IH and IF MNs using an intersectional genetic approach.
Motor Neurons , Spinal Cord , Animals , Basic Helix-Loop-Helix Transcription Factors/genetics , Mice , Muscle, Skeletal
Abstract Ribes and López's (1985) taxonomy proposed that psychological behavior is progressively complex and inclusive. In that respect, there is little research and data are not robust. A study was conducted with the purpose to increase data related to the complexity and inclusivity of the three less complex behaviors of the taxonomy, with three training sequences, namely: 1) ascending (contextual-supplementary-selector), 2) descending-ascending (supplementary -contextual-selector) and 3) descending (selector-supplementary-contextual). The objective was to evaluate the effect of the interaction history (related to training sequences) on differential (contextual), effective (supplementary) and precise (selector) behavior adjustment process. Results showed that a greater number of training sessions were required to improve the performance in functional organizations with greater complexity when participants lacked an interaction history related to programmed contingencies. But, when the interaction history participated in the functional organization, as a previous interaction with the contingencies, a facilitating effect was found in the behavioral adjustment, regardless of whether the transition was ascending or descending. It is discussed whether the increase in the number of sessions is related to the complexity of each level of functional organization. Regarding the functional training transitions, ascending and descending, its effects on facilitation in learning are discussed in relation to the assumption of functional inclusivity.
Resumen En la taxonomía de Ribes y López (1985) se propone que el comportamiento psicológico es progresivamente complejo e inclusivo; sin embargo, en la literatura sobre el tema se encuentran pocas investigaciones y los datos no son robustos. Teniendo esto en cuenta, y con el propósito de aumentar la evidencia de la complejidad e inclusividad de los tres primeros niveles de complejidad conductual de la taxonomía en tres secuencias de entrenamiento -ascendente (contextual-suplementario-selector), descendente-ascendente (suplementario-contextual-selector) y descendente (selector-suplementario-contextual)-, el presente estudio tuvo como objetivo evaluar el efecto de la historia de interacción -por medio de secuencias de entrenamiento- sobre el proceso de ajuste diferencial (contextual), efectivo (suplementario) y preciso (selector). En general, los resultados muestran que cuando los participantes carecían de historia de interacción ante las contingencias programadas se requirió de un mayor número de sesiones de entrenamiento para mejorar el desempeño en organizaciones funcionales de mayor complejidad; y que cuando la historia de interacción estaba presente en la organización funcional -en tanto interacción previa con las contingencias- se encontró un efecto de facilitación en el ajuste conductual, independientemente de si la transición fue ascendente o descendente. Al final se indaga sobre si el incremento en el número de sesiones se relaciona con la complejidad de cada nivel de organización funcional, y se discute, respecto a las transiciones de entrenamiento funcional, ascendente y descendente, sus efectos en la facilitación en el aprendizaje y su relación con el supuesto de inclusividad funcional.
PURPOSE: This study aimed to cross culturally adapt the Protocol for the Exploration of Natural Metalinguistic Skills in Aphasia (MetAphAs), contributing to the future application in the aphasic Chilean population. METHOD: The sample corresponds to 72 healthy subjects in the region of Valparaíso, between the ages of 50 to 85. The MetAphAs measures natural metalinguistic skills and presents the basic elements on which to base the exploration of the metacognitive dimensions involved in verbal behavior. The validity was ascertained by means of Cronbach's Alpha Coefficient, including the values of each of the 6 sections; the correlations between variables were analyzed by the Pearson coefficient. RESULTS: We observed that 64% of the sample corresponded to the female and 36% to the male gender, with predominant age ranging from 61 to 70 years. We verified adequate correlation between the variables according to the Pearson coefficient, and highly positive values according to Cronbach's Alpha. CONCLUSION: The use of the protocol is viable, with data demonstrating high reliability. The results evidenced high liability, which encourages the continuation process of its validation with Chilean aphasic population.
OBJETIVO: El objetivo de este estudio fue adaptar transculturalmente el Protocolo de Exploración de Habilidades Metalingüísticas Naturales en Afasia (MetAphAs), contribuyendo a la aplicación futura del instrumento en la población afásica chilena. MÉTODO: la muestra corresponde a 72 individuos sanos de la región de Valparaíso, de 50 a 85 años. El Protocolo MetAphAs mide las habilidades metalingüísticas naturales y presenta los elementos básicos en los que debe basarse una exploración de la dimensión metacognitiva involucrada en el comportamiento verbal. La validez se verificó mediante el coeficiente alfa de Cronbach, incluidos los valores de cada una de las 6 secciones; las correlaciones entre las variables fueron analizadas por el coeficiente de Pearson. RESULTADOS: el 64% de la muestra correspondió a mujeres y el 36% a hombres, con el mayor grupo de edad de participación de 61 a 70 años; se verifica una correlación adecuada entre las variables según el coeficiente de Pearson y los valores altamente positivos según el alfa de Cronbach. CONCLUSIÓN: el uso del protocolo fue factible y relevante, con datos que demostraron una alta confiabilidad. Los resultados obtenidos y las ventajas indicadas alientan el uso de este tipo de instrumento como una opción viable para la validación en afásicos chilenos.
Aphasia , Aged , Aged, 80 and over , Aphasia/diagnosis , Chile , Female , Humans , Linguistics , Male , Middle Aged , Psychometrics , Reproducibility of Results
RESUMEN Objetivo: El objetivo de este estudio fue adaptar transculturalmente el Protocolo de Exploración de Habilidades Metalingüísticas Naturales en Afasia (MetAphAs), contribuyendo a la aplicación futura del instrumento en la población afásica chilena. Método: la muestra corresponde a 72 individuos sanos de la región de Valparaíso, de 50 a 85 años. El Protocolo MetAphAs mide las habilidades metalingüísticas naturales y presenta los elementos básicos en los que debe basarse una exploración de la dimensión metacognitiva involucrada en el comportamiento verbal. La validez se verificó mediante el coeficiente alfa de Cronbach, incluidos los valores de cada una de las 6 secciones; las correlaciones entre las variables fueron analizadas por el coeficiente de Pearson. Resultados: el 64% de la muestra correspondió a mujeres y el 36% a hombres, con el mayor grupo de edad de participación de 61 a 70 años; se verifica una correlación adecuada entre las variables según el coeficiente de Pearson y los valores altamente positivos según el alfa de Cronbach. Conclusión: el uso del protocolo fue factible y relevante, con datos que demostraron una alta confiabilidad. Los resultados obtenidos y las ventajas indicadas alientan el uso de este tipo de instrumento como una opción viable para la validación en afásicos chilenos.
ABSTRACT Purpose: This study aimed to cross culturally adapt the Protocol for the Exploration of Natural Metalinguistic Skills in Aphasia (MetAphAs), contributing to the future application in the aphasic Chilean population. Method: The sample corresponds to 72 healthy subjects in the region of Valparaíso, between the ages of 50 to 85. The MetAphAs measures natural metalinguistic skills and presents the basic elements on which to base the exploration of the metacognitive dimensions involved in verbal behavior. The validity was ascertained by means of Cronbach's Alpha Coefficient, including the values of each of the 6 sections; the correlations between variables were analyzed by the Pearson coefficient. Results: We observed that 64% of the sample corresponded to the female and 36% to the male gender, with predominant age ranging from 61 to 70 years. We verified adequate correlation between the variables according to the Pearson coefficient, and highly positive values according to Cronbach's Alpha. Conclusion: The use of the protocol is viable, with data demonstrating high reliability. The results evidenced high liability, which encourages the continuation process of its validation with Chilean aphasic population.
Humans , Male , Female , Aged , Aged, 80 and over , Aphasia/diagnosis , Psychometrics , Chile , Reproducibility of Results , Linguistics , Middle Aged
In this paper, we report the design of an aperiodic remote formation controller applied to nonholonomic robots tracking nonlinear, trajectories using an external positioning sensor network. Our main objective is to reduce wireless communication with external sensors and robots while guaranteeing formation stability. Unlike most previous work in the field of aperiodic control, we design a self-triggered controller that only updates the control signal according to the variation of a Lyapunov function, without taking the measurement error into account. The controller is responsible for scheduling measurement requests to the sensor network and for computing and sending control signals to the robots. We design two triggering mechanisms: centralized, taking into account the formation state and decentralized, considering the individual state of each unit. We present a statistical analysis of simulation results, showing that our control solution significantly reduces the need for communication in comparison with periodic implementations, while preserving the desired tracking performance. To validate the proposal, we also perform experimental tests with robots remotely controlled by a mini PC through an IEEE 802.11g wireless network, in which robots pose is detected by a set of camera sensors connected to the same wireless network.
El presente trabajo contó con el propósito de señalar y, en la medida de lo posible, resolver algunos de los problemas conceptuales relacionados con el área de conocimiento que comúnmente se denomina desarrollo psicológico. El primer paso para lograr esto, consistió en clarificar si el desarrollo psicológico es una subdisciplina de la psicología o es un área en la que convergen distintas disciplinas. Conforme se avanzó hacia estos objetivos, fue imperante describir, de forma introductoria, las estrategias que se han implementado desde la psicología interconductual para resolver los problemas relacionados con la definición de desarrollo psicológico y, por lo tanto, con el objeto de estudio de la psicología. Partiendo de la definición de este objeto, fue posible distinguir entre el desarrollo humano como un área de conocimiento en la que convergen distintas disciplinas y el desarrollo psicológico como ámbito de la psicología, superando así las confusiones originadas del tomarlas como equivalentes. Finalmente, se definió el desarrollo psicológico con base en las competencias funcionales y se discutió la pertenencia de sustituir el concepto de desarrollo por el de devenir psicológico.
The present work had the purpose of pointing out and solving some of the conceptual problems related to the area of knowledge called psychological development. The first step in achieving this was to clarify whether psychological development is a sub-discipline of psychology or an area in which different disciplines converge. As objectives were reached, it was imperative to describe, in an introductory way, the strategies that have been implemented from interbehavioral psychology to solve the problems related to the definition of psychological development and, therefore, with the object of psychology study. Starting from the definition of this object, it was possible to distinguish between human development as an area of knowledge in which different disciplines converge and psychological development as an area of psychology, overcoming the confusions originated from taking them as equivalents. Finally, psychological development was defined based on functional competencies, and the relevance of replacing the concept of development with psychological becoming was discussed.
Copy-number variants of chromosome 16 region 16p11.2 are linked to neuropsychiatric disorders and are among the most prevalent in autism spectrum disorders. Of many 16p11.2 genes, Kctd13 has been implicated as a major driver of neurodevelopmental phenotypes. The function of KCTD13 in the mammalian brain, however, remains unknown. Here we delete the Kctd13 gene in mice and demonstrate reduced synaptic transmission. Reduced synaptic transmission correlates with increased levels of Ras homolog gene family, member A (RhoA), a KCTD13/CUL3 ubiquitin ligase substrate, and is reversed by RhoA inhibition, suggesting increased RhoA as an important mechanism. In contrast to a previous knockdown study, deletion of Kctd13 or kctd13 does not increase brain size or neurogenesis in mice or zebrafish, respectively. These findings implicate Kctd13 in the regulation of neuronal function relevant to neuropsychiatric disorders and clarify the role of Kctd13 in neurogenesis and brain size. Our data also reveal a potential role for RhoA as a therapeutic target in disorders associated with KCTD13 deletion.
Brain/metabolism , Carrier Proteins/metabolism , Gene Deletion , Synaptic Transmission/genetics , Zebrafish Proteins/metabolism , rho GTP-Binding Proteins/metabolism , Animals , Autism Spectrum Disorder/genetics , Autism Spectrum Disorder/psychology , Autistic Disorder/genetics , Autistic Disorder/psychology , Brain/anatomy & histology , Brain/cytology , Brain/pathology , CA1 Region, Hippocampal/metabolism , CA1 Region, Hippocampal/pathology , Carrier Proteins/genetics , Chromosome Deletion , Chromosome Disorders/genetics , Chromosome Disorders/psychology , Chromosomes, Human, Pair 16/genetics , Cullin Proteins/metabolism , Female , Intellectual Disability/genetics , Intellectual Disability/psychology , Male , Mice , Multifactorial Inheritance/genetics , Neurogenesis/genetics , Organ Size/genetics , Reproducibility of Results , Synaptic Transmission/drug effects , Ubiquitin-Protein Ligase Complexes , Zebrafish , Zebrafish Proteins/genetics , rho GTP-Binding Proteins/antagonists & inhibitors , rhoA GTP-Binding Protein
In recent years, indoor localization systems have been the object of significant research activity and of growing interest for their great expected social impact and their impressive business potential. Application areas include tracking and navigation, activity monitoring, personalized advertising, Active and Assisted Living (AAL), traceability, Internet of Things (IoT) networks, and Home-land Security. In spite of the numerous research advances and the great industrial interest, no canned solutions have yet been defined. The diversity and heterogeneity of applications, scenarios, sensor and user requirements, make it difficult to create uniform solutions. From that diverse reality, a main problem is derived that consists in the lack of a consensus both in terms of the metrics and the procedures used to measure the performance of the different indoor localization and navigation proposals. This paper introduces the general lines of the EvAAL benchmarking framework, which is aimed at a fair comparison of indoor positioning systems through a challenging competition under complex, realistic conditions. To evaluate the framework capabilities, we show how it was used in the 2016 Indoor Positioning and Indoor Navigation (IPIN) Competition. The 2016 IPIN competition considered three different scenario dimensions, with a variety of use cases: (1) pedestrian versus robotic navigation, (2) smartphones versus custom hardware usage and (3) real-time positioning versus off-line post-processing. A total of four competition tracks were evaluated under the same EvAAL benchmark framework in order to validate its potential to become a standard for evaluating indoor localization solutions. The experience gained during the competition and feedback from track organizers and competitors showed that the EvAAL framework is flexible enough to successfully fit the very different tracks and appears adequate to compare indoor positioning systems.
This paper describes the theoretical and practical foundations for remote control of a mobile robot for nonlinear trajectory tracking using an external localisation sensor. It constitutes a classical networked control system, whereby event-based techniques for both control and state estimation contribute to efficient use of communications and reduce sensor activity. Measurement requests are dictated by an event-based state estimator by setting an upper bound to the estimation error covariance matrix. The rest of the time, state prediction is carried out with the Unscented transformation. This prediction method makes it possible to select the appropriate instants at which to perform actuations on the robot so that guidance performance does not degrade below a certain threshold. Ultimately, we obtained a combined event-based control and estimation solution that drastically reduces communication accesses. The magnitude of this reduction is set according to the tracking error margin of a P3-DX robot following a nonlinear trajectory, remotely controlled with a mini PC and whose pose is detected by a camera sensor.
When addressing the problem of state estimation in sensor networks, the effects of communications on estimator performance are often neglected. High accuracy requires a high sampling rate, but this leads to higher channel load and longer delays, which in turn worsens estimation performance. This paper studies the problem of determining the optimal sampling rate for state estimation in sensor networks from a theoretical perspective that takes into account traffic generation, a model of network behaviour and the effect of delays. Some theoretical results about Riccati and Lyapunov equations applied to sampled systems are derived, and a solution was obtained for the ideal case of perfect sensor information. This result is also interesting for non-ideal sensors, as in some cases it works as an upper bound of the optimisation solution.
Together with its presynaptic partner Neurexin 1 (Nxn1), Neuroligin 1 (NL1) participates in synapse specification and synapse maintenance. We and others have shown that NL1 can also modulate glutamatergic synaptic function in the central nervous system of rodent models. These molecular/cellular changes can translate into altered animal behaviors that are thought to be analogous to symptomatology of neuropsychiatric disorders. For example, in dorsal striatum of NL1 deletion mice, we previously reported that the ratio N-methyl-D-aspartate receptor (NMDAR) mediated synaptic currents to α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor (AMPAR) mediated synaptic currents (NMDA/AMPA) is reduced in medium spiny neuron (MSNs). Importantly, this reduction in NMDA/AMPA ratio correlated with increased repetitive grooming. The striatum is the input nucleus of the basal ganglia (BG). Classical models of this circuitry imply that there are two principal pathways that render distinct and somewhat opposite striatal outputs critical to the function of these nuclei in modulating motor behavior. Thus, we set out to better characterize the effects of NL1 deletion on direct and indirect pathways of the dorsal striatum by genetically labeling MSNs participating in the direct and indirect pathways. We demonstrate that a decrease in NMDAR-mediated currents is limited to MSNs of the direct pathway. Furthermore, the decrease in NMDAR-mediated currents is largely due to a reduction in function of NMDARs containing the GluN2A subunit. In contrast, indirect pathway MSNs in NL1 knockout (KO) mice showed a reduction in the frequency of miniature excitatory neurotransmission not observed in the direct pathway. Thus, NL1 deletion differentially affects direct and indirect pathway MSNs in dorsal striatum. These findings have potential implications for striatal function in NL1 KO mice.
For the problem of pose estimation of an autonomous vehicle using networked external sensors, the processing capacity and battery consumption of these sensors, as well as the communication channel load should be optimized. Here, we report an event-based state estimator (EBSE) consisting of an unscented Kalman filter that uses a triggering mechanism based on the estimation error covariance matrix to request measurements from the external sensors. This EBSE generates the events of the estimator module on-board the vehicle and, thus, allows the sensors to remain in stand-by mode until an event is generated. The proposed algorithm requests a measurement every time the estimation distance root mean squared error (DRMS) value, obtained from the estimator's covariance matrix, exceeds a threshold value. This triggering threshold can be adapted to the vehicle's working conditions rendering the estimator even more efficient. An example of the use of the proposed EBSE is given, where the autonomous vehicle must approach and follow a reference trajectory. By making the threshold a function of the distance to the reference location, the estimator can halve the use of the sensors with a negligible deterioration in the performance of the approaching maneuver.
