Search

The septum is a ventral forebrain structure known to regulate innate behaviors. During embryonic development, septal neurons are produced in multiple proliferative areas from neural progenitors following transcriptional programs that are still largely unknown. Here, we use a combination of single-cell RNA sequencing, histology, and genetic models to address how septal neuron diversity is established during neurogenesis. We find that the transcriptional profiles of septal progenitors change along neurogenesis, coinciding with the generation of distinct neuron types. We characterize the septal eminence, an anatomically distinct and transient proliferative zone composed of progenitors with distinctive molecular profiles, proliferative capacity, and fate potential compared to the rostral septal progenitor zone. We show that Nkx2.1-expressing septal eminence progenitors give rise to neurons belonging to at least three morphological classes, born in temporal cohorts that are distributed across different septal nuclei in a sequential fountain-like pattern. Our study provides insight into the molecular programs that control the sequential production of different neuronal types in the septum, a structure with important roles in regulating mood and motivation.

To understand the function of cortical circuits, it is necessary to catalog their cellular diversity. Past attempts to do so using anatomical, physiological or molecular features of cortical cells have not resulted in a unified taxonomy of neuronal or glial cell types, partly due to limited data. Single-cell transcriptomics is enabling, for the first time, systematic high-throughput measurements of cortical cells and generation of datasets that hold the promise of being complete, accurate and permanent. Statistical analyses of these data reveal clusters that often correspond to cell types previously defined by morphological or physiological criteria and that appear conserved across cortical areas and species. To capitalize on these new methods, we propose the adoption of a transcriptome-based taxonomy of cell types for mammalian neocortex. This classification should be hierarchical and use a standardized nomenclature. It should be based on a probabilistic definition of a cell type and incorporate data from different approaches, developmental stages and species. A community-based classification and data aggregation model, such as a knowledge graph, could provide a common foundation for the study of cortical circuits. This community-based classification, nomenclature and data aggregation could serve as an example for cell type atlases in other parts of the body.

Objective: This study aims to describe the accessibility to and promotion of alcohol and tobacco around secondary schools in Madrid and its distribution in relation with area-level socioeconomic deprivation; analyze the relationship between this exposure and individual consumption characteristics of students between 14 and 18 years old; and explore other facilitators of this consumption. Method: Mixed-methods study conducted in three phases: 1) we collected data on accessibility to and promotion of alcohol and tobacco in the environment using systematic social observation around 55 secondary schools; 2) we administered 2287 questionnaires among the students in these centers to gather information about characteristics and determinants of consumption; and 3) we conducted 20 semi-structured interviews and one discussion group to deepen in the results obtained in surveys and systematic social observation. We will use Geographic Information Systems to integrate and analyze the data from a spatial perspective. Resumen: Objetivo: Este estudio tiene como objetivo describir la accesibilidad y la promoción de alcohol y tabaco alrededor de los centros de enseñanza secundaria en Madrid y su distribución en relación con la privación socioeconómica del área; analizar la relación entre esta exposición y las características individuales de consumo en estudiantes de entre 14 y 18 años; y explorar otros facilitadores del consumo. Método: Estudio de métodos mixtos en tres fases: 1) recogimos datos sobre accesibilidad y promoción de estas sustancias en el entorno mediante observación social sistemática alrededor de 55 centros de secundaria; 2) administramos 2287 cuestionarios a estudiantes de estos centros sobre características y determinantes de consumo; y 3) realizamos 20 entrevistas semiestructuradas y un grupo de discusión en estos centros para profundizar en los resultados obtenidos en las encuestas y la observación social sistemática. Utilizaremos Sistemas de Información Geográfica para integrar y analizar los datos desde una perspectiva espacial.

The septum is a ventral forebrain structure known to regulate innate behaviors. During embryonic development, septal neurons are produced in multiple proliferative areas from neural progenitors following transcriptional programs that are still largely unknown. Here, we use a combination of single-cell RNA sequencing, histology, and genetic models to address how septal neuron diversity is established during neurogenesis. We find that the transcriptional profiles of septal progenitors change along neurogenesis, coinciding with the generation of distinct neuron types. We characterize the septal eminence, an anatomically distinct and transient proliferative zone composed of progenitors with distinctive molecular profiles, proliferative capacity, and fate potential compared to the rostral septal progenitor zone. We show that Nkx2.1-expressing septal eminence progenitors give rise to neurons belonging to at least three morphological classes, born in temporal cohorts that are distributed across different septal nuclei in a sequential fountain-like pattern. Our study provides insight into the molecular programs that control the sequential production of different neuronal types in the septum, a structure with important roles in regulating mood and motivation.

The mammalian neocortex is composed of two major neuronal cell types with distinct origins: excitatory pyramidal neurons and inhibitory interneurons, generated in dorsal and ventral progenitor zones of the embryonic telencephalon, respectively. Thus, inhibitory neurons migrate relatively long distances to reach their destination in the developing forebrain. The role of lineage in the organization and circuitry of interneurons is still not well understood. Utilizing a combination of genetics, retroviral fate mapping, and lineage-specific retroviral barcode labeling, we find that clonally related interneurons can be widely dispersed while unrelated interneurons can be closely clustered. These data suggest that migratory mechanisms related to the clustering of interneurons occur largely independent of their clonal origin.

The factors determining regional adaptation in salmonids are still unclear, but it is known that changes in their habitat imply changes in their population structure. In this preliminary study we integrate habitat data, molecular analyses (from both nuclear microsatellite and mitochondrial loci) and life-history traits (measured on archaeological vertebrae and modern scales) of two sympatric salmonid species: Atlantic salmon and brown trout. We propose that water temperature and geological characteristics changed the biogeographic patterns of these species through asymmetric migration and different (but complementary) population growth rates. As a consequence, differences in a life-history trait (mean number of years at sea) and population sizes were detected between regions, suggesting a process of substitution of Atlantic salmon by brown trout.

Bentonite is a claystone formed by a complex mineralogical mixture, composed of montmorillonite, illite, and accessory minerals like quartz, cristobalite, feldspars, carbonates, and minor amounts of iron oxy-hydroxides. Bentonite presents complexity at various scales: (1): a single mineral may present different chemical composition within the same quarry (e.g., feldspars solid solutions); (2): montmorillonite presents variability in the cation-exchange distribution while illite may be presented as mixed-layer with smectite sheets; and (3): hardness and crystal size are larger in accessory minerals than in clay minerals, preventing uniform grinding of bentonite. The FEBEX bentonite used is originally from Almería (Spain), and it is a predominantly calcium, magnesium, and sodium bentonite. This Spanish FEBEX bentonite has been hydrothermally altered at laboratory scale for 7–14 years. A thermal gradient was generated by heating a disk of pressed iron powder, simulating the metal waste canister, in contact with the compacted bentonite sample. Hydration was forced from the opposite direction. XRD recorded patterns were very similar. In order to minimize the bias of XRD semi-quantitative determination methods, Rietveld refinement was performed using BGMN software and different structural models. Confidence in the quantification of the main phases allows us to convincingly detect other subtle changes such as the presence of calcite in the hydration front, right at the interface between the saturated and unsaturated bentonite, or the presence of goethite, and not hematite, in the saturated bentonite, near the source of hydration. Smectite component was 72 ± 3% and the refinement was consistent with the presence of ~10% illite, comparable with previous characterizations.

The mouse cerebral cortex contains neurons that express choline acetyltransferase (ChAT) and are a potential local source of acetylcholine. However, the neurotransmitters released by cortical ChAT+ neurons and their synaptic connectivity are unknown. We show that the nearly all cortical ChAT+ neurons in mice are specialized VIP+ interneurons that release GABA strongly onto other inhibitory interneurons and acetylcholine sparsely onto layer 1 interneurons and other VIP+/ChAT+ interneurons. This differential transmission of ACh and GABA based on the postsynaptic target neuron is reflected in VIP+/ChAT+ interneuron pre-synaptic terminals, as quantitative molecular analysis shows that only a subset of these are specialized to release acetylcholine. In addition, we identify a separate, sparse population of non-VIP ChAT+ neurons in the medial prefrontal cortex with a distinct developmental origin that robustly release acetylcholine in layer 1. These results demonstrate both cortex-region heterogeneity in cortical ChAT+ interneurons and target-specific co-release of acetylcholine and GABA.

Previous studies have found a facilitative memory effect for emotional content words in both L1 and L2 speakers (Rubin & Friendly, 1986; Anooshian & Hertel, 1994; Altarriba & Bauer, 2004; Ayiçiçegi-Dinn & Caldwell-Harris, 2009). The present study investigates how emotional affect, activated through visual and auditory cues, effects L2 Spanish speakers’ acquisition of novel lexical items. Data from Picture Matching and Naming tasks suggest that positive emotional context has a facilitative effect on learners’ recognition and recall of target items when compared to the emotionally neutral or negative contexts. The implication of these results in L2 pedagogy suggests that lexical acquisition and retention can be enhanced by the incorporation of course materials with a positive emotional drive.

Spinal cord injury (SCI) results in long-term neurological and systemic consequences, including antibody-mediated autoimmunity, which has been related to impaired functional recovery. Here we show that autoantibodies that increase at the subacute phase of human SCI, 1 month after lesion, are already present in healthy subjects and directed against non-native proteins rarely present in the normal spinal cord. The increase of these autoantibodies is a fast phenomenon–their levels are already elevated before 5 days after lesion–characteristic of secondary immune responses, further supporting their origin as natural antibodies. By proteomics studies we have identified that the increased autoantibodies are directed against 16 different nervous system and systemic self-antigens related to changes known to occur after SCI, including alterations in neural cell cytoskeleton, metabolism and bone remodeling. Overall, in the context of previous studies, our results offer an explanation to why autoimmunity develops after SCI and identify novel targets involved in SCI pathology that warrant further investigation.

The Derivational Complexity Hypothesis (Jakubowicz & Strik 2008) proposes that computationally complex structures interact with syntactic constraints in linguistic production, causing the rise of avoidance strategies in child L1 and adult L2 speakers. These avoidance strategies have until recently been understudied in the field of SLA (as opposed to the use of ungrammatical structures), but they actively compete with target-like forms during the language acquisition process and can therefore advance our understanding of non-native linguistic development. This article provides evidence for the DCH based on avoidance strategies shown by non-native speakers of Spanish in the production of the wh- island (How did you say when the jewels were stolen?). Through a game-based elicitation task, speakers at the intermediate and near-native level were prompted to produce questions containing a wh- island. The results show that intermediate speakers of Spanish significantly avoid producing questions that contain an island, as opposed to native and near-native speakers. The strategies used instead of the target are of a less complex nature (pronominalization of the second clause, omission of the middle verb), therefore supporting the DCH. Near-native and native data, on the other hand, show a use of creative strategies that is absent from the intermediate data. Off-target constructions by these groups often consist of questions that are structurally more complex than the intended target forms (use of relative clauses and embedded NPs).

Artificial and singular geochemical environments are created around the engineered barrier systems (EBS) designed to isolate high level nuclear wastes in deep geological repositories. A concrete-bentonite interface takes place within the EBS and it builds a significant chemical gradient (pH), approximately from pH 8 (bentonite) to pH 12 (low alkali concrete), in a few millimetre thickness. This disequilibrium triggers dissolution and precipitation reactions and form a thin altered region. In this area, poorly ordered authigenic clay minerals, mainly hydrated magnesium silicates, are formed adjacent to hydrated calcium silicates and calcite precipitates adhered to the interface with concrete. This paper presents the development of this authigenic mineral layer comparing 6–18 months to 13 years interfaces. Scanning Electron Microscopy with Energy Dispersive X-ray spectroscopy (SEM-EDX) morphological and chemical characterization with the aid of ternary plots, X-ray diffraction (XRD) and infrared (IR) data show the young to old interface evolution from single brucite layers to stevensite-saponite silicates composition. Geochemical calculations indicate that this layer acts as a pH~11 buffer useful to minimize bentonite alteration and to favour the retention of amphoteric metal ions.

Este artículo presenta una descripción práctica de las cuestiones y procedimientos necesarios para la involucración de personas con discapacidad en proyectos tecnológicos de I+D+i. Se parte de la justificación de esta necesidad, fundamentada en nuevos paradigmas como la investigación inclusiva o emancipatoria. Se realiza un repaso de aspectos prácticos que afectan a las fases y actividades en las que la participación de personas con discapacidad es pertinente (ideación y planificación, recogida de requisitos, diseño y desarrollo y experiencia piloto y validación). Asimismo, se utilizan datos y resultados de un proyecto concreto de I+D+i (APSIS4all) para ilustrar los procedimientos a realizar en cada una de las fases. En conjunto, el artículo sugiere que la participación de personas con discapacidad en un proyecto de estas características no es solo posible sino también deseable.

The factors determining regional adaptation in salmonids are still unclear, but it is known that changes in their habitat imply changes in their population structure. In this preliminary study we integrate habitat data, molecular analyses (from both nuclear microsatellite and mitochondrial loci) and life-history traits (measured on archaeological vertebrae and modern scales) of two sympatric salmonid species: Atlantic salmon and brown trout. We propose that water temperature and geological characteristics changed the biogeographic patterns of these species through asymmetric migration and different (but complementary) population growth rates. As a consequence, differences in a life-history trait (mean number of years at sea) and population sizes were detected between regions, suggesting a process of substitution of Atlantic salmon by brown trout.

A comparison of Upper Palaeolithic and contemporary salmonid vertebrae from the Iberian Peninsula indicates that there has been a significant decrease in the mean body size for a given age among Atlantic salmon and brown trout inhabiting the southernmost range of their endemic distribution. Mean size at age was greater in prehistoric specimens for all age classes during the freshwater phase of their life histories. Fisheries-induced evolution (selection for smaller sizes) is an obvious explanation for the observed reduction in fish body size, but recent changes in the aquatic habitat affecting density-dependent growth cannot be ruled out.

Los procesos de alteración mineral superficial dan lugar a la adquisición de las características físico-químicas de las aguas naturales mediante procesos de interacción con la fase sólida con la que se pone en contacto a través del ciclo hidrogeológico. Las aguas de lluvia comienzan a adquirir los principales componentes químicos al percolar a través de la zona insaturada por medio de intercambios iónicos con el complejo de intercambio catiónico de los suelos. La alteración hipergénica de las rocas primarias provoca la aparición de los minerales secundarios y se refleja en la incorporación de nuevos solutos a las aguas. El origen de la composición del agua subterránea de las rocas ígneas podría conocerse mediante modelos químicos cuantitativos relativamente sencillos si se conocieran determinadas incógnitas sobre las constantes termodinámicas de algunos productos de alteración mineral. La oxidación de sulfuros y la reducción de sulfatos son dos de los principales procesos hidrogeoquímicos redox que confieren a las aguas características relacionadas con aumentos y descensos de los potenciales de oxidación-reducción. En ambos procesos las bacterias actúan como catalizadores esenciales que regulan la cinética de las reacciones. La formación de dolomita y su proceso de ruptura es propio de formaciones carbonatadas y confieren a las aguas características químicas distintas debido a la presencia de estos nuevos solutos. Los procesos de dolomitización presentan problemas en relación con la cinética de las reacciones.

Over three months of intensive training with a tactile stimulation device, 18 blind and 10 blindfolded seeing subjects improved in their ability to identify geometric figures by touch. Seven blind subjects spontaneously reported 'visual qualia', the subjective sensation of seeing flashes of light congruent with tactile stimuli. In the latter subjects tactile stimulation evoked activation of occipital cortex on electroencephalography (EEG). None of the blind subjects who failed to experience visual qualia, despite identical tactile stimulation training, showed EEG recruitment of occipital cortex. None of the blindfolded seeing humans reported visual-like sensations during tactile stimulation. These findings support the notion that the conscious experience of seeing is linked to the activation of occipital brain regions in people with blindness. Moreover, the findings indicate that provision of visual information can be achieved through non-visual sensory modalities which may help to minimize the disability of blind individuals, affording them some degree of object recognition and navigation aid.

El estudio de los posibles emplazamientos de residuos radiactivos en un medio geológico cualquiera en profundidad, requiere la caracterización de los parámetros hidrogeológicos e hidrogeoquímicos que controlan la migración de los radionucleidos hacia la biosfera. Para llevar a cabo esa caracterización se ha desarrollado una metodología que incluye: (1) estudio sistemático y minucioso de sondeos profundos con el fin de seleccionar zonas favorables para el muestreo del agua y su caracterización; (2) sellado de las zonas seleccionadas mediante obturadores; (3) bombeo de agua de la zona aislada, mediante bombas o sistemas de elevación con gas, con el fin de eliminar la contaminación producida por el agua de perforación. El control de la limpieza se realiza mediante el seguimiento de trazadores y la estabilización de los parámetros físico-químicos del agua; (4) muestreo y análisis in situ de agua, gases, partículas, coloides y microorganismos, para 10 cual se ha diseñado una unidad móvil de caracterización hidrogeoquímica (UMCH) que permite determinar in situ los parámetros más sensibles, evitando así los problemas de alteración debidos al transporte de las muestras.

En relación con los procesos de migración/retención de los radionucleidos naturales en un medio granítico fisurado se han estudiado los rellenos fisurales arcillosos (< 60 μm y < 2 μm) asociados con las fracturas N100-110 ºE de la mina de U de El Berrocal. La fractura rellena por el filón de cuarzo mineralizado con pirita, calcopirita, esfalerita y galena; y posteriormente por pirita, pechblenda, calcita y barita, pertenece también a dicha familia de fracturas. De acuerdo con los datos difractométricos, termogravimétricos, de energías dispersivas de rayos X acoplado a sendos microscopios electrónicos de barrido y transmisión y del análisis del complejo catiónico de cambio, los rellenos arcillosos están esencialmente constituídos por cuarzo, sericita, ilita, beidellita cálcico-magnésica, feldespato potásico, albita, apatito y ocasionalmente caolinita. La monacita, torbernita, autunita, otros fosfatos de Ca, Y, Ce, La y TR no clasificados, sulfato férrico, jarosita, yeso, barita, calcita, silicatos de Pb, oxihidróxidos de Fe, gibbsita, geles de Al y geles silicatados complejos de TR están como trazas en la fracción < 2 μm. Desde el punto de vista geoquímico, la fracción < 2 μm de las muestras está enriquecida en U, Th, V, Cu, Zn, Sn, Ni, As, Ba, Ca y C orgánico, en relación con la fracción < 60 μm. Además, el CI está presente, en concentraciones importantes, en casi todos los minerales y mineraloides de la fracción < 2 μm. Estos datos sugieren que los materiales arcillosos estudiados se originaron por alteración hidrotermal de las harinas de falla, durante la fase -110 ºE de fracturación. De acuerdo con los datos de δ 18O obtenidos del cuarzo filoniano y de la fracción < 2 μm de las muestras, el proceso de arcillización se produjo probablemente en dos fases. La primera, de naturaleza sericítico-ilítica, se originó por la interacción entre las harinas graníticas de falla y soluciones hidrotermales ácidas, ricas en KCI, en un rango de temperaturas comprendido entre 70-120 °C. La segunda fase, de naturaleza esmectítica, se produjo probablemente durante los procesos de alteración meteórica, antiguos y/o actuales, por fuerte lixiviación del K de la sericita-ilita preexistentes. Esta fase de alteración meteórica pudo ser también la responsable de la transformación de la ilita y, probablemente, la esmectita en caolinita, en aquellas fracturas mineralizadas con sulfuros. La jarosita, los sulfatos de Fe, el yeso, la torbernita, la autunita, la gibbsita y los geles de Al se originarían probablemente también en esta última fase de alteración meteórica. Los minerales y mineraloides accesorios neoformados juegan un papel importante en la retención, por precipitación o adsorción, de los elementos radiactivos, U y Th, Yotros análogos, Y, Ce, La, REE, liberados durante la alteración hidrotermal del granito y meteórica de la mineralización uranífera. El Th está principalmente en la estructura de la monacita heredada. La lixiviación secuencial del U indica que los oxihidróxidos de Fe y los carbonatos retienen cantidades relativamente importantes de dicho elemento, mientras que los minerales de la arcilla no parecen jugar un papel importante en la retención del U por adsorción. No obstante, pudieron actuar como una barrera físico-química para la precipitación de los fosfatos de UO2++. El alto contenido en C orgánico de la fracción arcilla de las muestras puede explicarse por la actividad bacteriana actual observada en los rellenos fisurales, o por la presencia de ácidos orgánicos, transportados por las aguas percolantes desde la superficie topográfica. En este último caso, han podido formarse complejos orgánico-arcillosos.

Copyright of Medicina (Buenos Aires) is the property of Medicina (Buenos Aires) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The evolutionary expansion of the neocortex primarily reflects increases in abundance and proliferative capacity of cortical progenitors and in the length of the neurogenic period during development. Cell cycle parameters of neocortical progenitors are an important determinant of cortical development. The ferret (Mustela putorius furo), a gyrencephalic mammal, has gained increasing importance as a model for studying corticogenesis. Here, we have studied the abundance, proliferation, and cell cycle parameters of different neural progenitor types, defined by their differential expression of the transcription factors Pax6 and Tbr2, in the various germinal zones of developing ferret neocortex. We focused our analyses on postnatal day 1, a late stage of cortical neurogenesis when upper‐layer neurons are produced. Based on cumulative 5‐ethynyl‐2′‐deoxyuridine (EdU) labeling as well as Ki67 and proliferating cell nuclear antigen (PCNA) immunofluorescence, we determined the duration of the various cell cycle phases of the different neocortical progenitor subpopulations. Ferret neocortical progenitors were found to exhibit longer cell cycles than those of rodents and little variation in the duration of G1 among distinct progenitor types, also in contrast to rodents. Remarkably, the main difference in cell cycle parameters among the various progenitor types was the duration of S‐phase, which became shorter as progenitors progressively changed transcription factor expression from patterns characteristic of self‐renewal to those of neuron production. Hence, S‐phase duration emerges as major target of cell cycle regulation in cortical progenitors of this gyrencephalic mammal. J. Comp. Neurol. 524:456–470, 2016. © 2015 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc.

Electronic waste sites are rich in heavy metals contained in electronic and electric equipment waste and pose a risk of pollution if metals enter in the environment nearby. The Korle lagoon, located in the center of Accra, is receiving waste effluents from industries, households and the adjacent e-waste burning site Agbogbloshie which is the biggest in the country. Thus, the risk of heavy metal contamination of the water body and subsequent uptake in the aquatic food chain is particularly relevant. Small-scale fishing, not entering the commercial chain, occurs in the lagoon despite its consideration of biologically dead. We assessed if the exposure to heavy metals through these fish consumption is posing higher health risks than fish sold on Ghanaian markets. Using ICP-MS technology, we quantified concentrations of As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in fish caught from the Korle Lagoon (Trachinotus ovatus , Mugil curema and Mugil cephalus) and compared them to fish from the Tema Newtown fishing market (Scomber colias , Pseudotolithus senegallus). Cobalt and lead concentrations, typical e-waste metals, were higher in fish from the Korle lagoon, even though they were of lower trophic level. Calculated risk indices revealed risk of elevated arsenic and mercury exposure, particularly through T. ovatus from the Korle lagoon, if consumed daily as it is common in the region. This study suggests the need of monitoring programs of Ghanaian catch, with a special focus in environmental risk areas like Korle lagoon to ensure human food safety. [Display omitted] • Korlee lagoon is not a biologically dead water body. • Higher WEEE metal content in fish living near e-waste sites • There is an important cobalt pollution in the fishes from in the lagoon. • Health risk assessment shows that consumption of standard meal sizes of analyzed species is totally discouraged. • Monitoring fish catches to ensure nutritional supply and prevent health hazards is necessary. [ABSTRACT FROM AUTHOR]