506 research outputs found
Electrophysiological Heterogeneity of Fast-Spiking Interneurons: Chandelier versus Basket Cells
In the prefrontal cortex, parvalbumin-positive inhibitory neurons play a prominent role in the neural circuitry that subserves working memory, and alterations in these neurons contribute to the pathophysiology of schizophrenia. Two morphologically distinct classes of parvalbumin neurons that target the perisomatic region of pyramidal neurons, chandelier cells (ChCs) and basket cells (BCs), are generally thought to have the same "fast-spiking" phenotype, which is characterized by a short action potential and high frequency firing without adaptation. However, findings from studies in different species suggest that certain electrophysiological membrane properties might differ between these two cell classes. In this study, we assessed the physiological heterogeneity of fast-spiking interneurons as a function of two factors: species (macaque monkey vs. rat) and morphology (chandelier vs. basket). We showed previously that electrophysiological membrane properties of BCs differ between these two species. Here, for the first time, we report differences in ChCs membrane properties between monkey and rat. We also found that a number of membrane properties differentiate ChCs from BCs. Some of these differences were species-independent (e.g., fast and medium afterhyperpolarization, firing frequency, and depolarizing sag), whereas the differences in the first spike latency between ChCs and BCs were species-specific. Our findings indicate that different combinations of electrophysiological membrane properties distinguish ChCs from BCs in rodents and primates. Such electrophysiological differences between ChCs and BCs likely contribute to their distinctive roles in cortical circuitry in each species. © 2013 Povysheva et al
Sensory hybrid host materials for the selective chromo-fluorogenic detection of biogenic amines
Pyrylium-containing mesoporous materials have been used for the chromo-fluorogenic sensing of biogenic amines in an aqueous environment.Amoros del Toro, Pedro Jose, [email protected]
Trends towards an improved disease state in rheumatoid arthritis over time: influence of new therapies and changes in management approach: analysis of the EMECAR cohort
Bifurcation study of a neural field competition model with an application to perceptual switching in motion integration.
Perceptual multistability is a phenomenon in which alternate interpretations of a fixed stimulus are perceived intermittently. Although correlates between activity in specific cortical areas and perception have been found, the complex patterns of activity and the underlying mechanisms that gate multistable perception are little understood. Here, we present a neural field competition model in which competing states are represented in a continuous feature space. Bifurcation analysis is used to describe the different types of complex spatio-temporal dynamics produced by the model in terms of several parameters and for different inputs. The dynamics of the model was then compared to human perception investigated psychophysically during long presentations of an ambiguous, multistable motion pattern known as the barberpole illusion. In order to do this, the model is operated in a parameter range where known physiological response properties are reproduced whilst also working close to bifurcation. The model accounts for characteristic behaviour from the psychophysical experiments in terms of the type of switching observed and changes in the rate of switching with respect to contrast. In this way, the modelling study sheds light on the underlying mechanisms that drive perceptual switching in different contrast regimes. The general approach presented is applicable to a broad range of perceptual competition problems in which spatial interactions play a role
Assessment of Accuracy of COSMIC and KOMPSAT Radio Occultation Temperature and Pressure
Radio Occultation is a technique used by orbiting satellites to measure planetary atmosphere properties like temperature, pressure, and water vapor. The aim of this study is to assess the radio occultation temperature and pressure profiles from the Constellation Observing System for Meteorology, Ionosphere and Climate 2 (COSMIC-2) and Korean Multi-purpose Satellite 5 (KOMPSAT5) using data from collocated radiosonde stations over the Philippines. Their deviations are analyzed using their mean and standard deviations. COSMIC-2 and KOMPSAT-5 temperature and pressure have good agreement with radiosondes in the stratosphere. From January to April of 2020, COSMIC-2 temperature standard deviation peaks with 0.072 K at 24.6 km. COSMIC-2 and KOMPSAT-5 pressure generally decreases with altitude. COSMIC-2 pressure standard deviation peaks with 0.06 hPa at 15 km. KOMPSAT-5 temperature standard deviation gradually increases with altitude with observed deviation peaks with 0.6 K at ~26.5 km. KOMPSAT-5 pressure standard deviation peaks with 0.02 hPa at 15 km. Seasonal variations between KOMPSAT-5 and radiosonde are usually lower in pressure deviation compared to temperature deviation. KOMPSAT-5 temperature standard deviation peaks at 23.24 km with 0.07 K during summer. KOMPSAT-5 pressure deviation is generally larger in the autumn season with a value of ~>0.02 hPa at 15 km. The quality of these results shows potential in COSMIC and KOMPSAT as high-quality applications for weather prediction
First faunistic results on Valencia (Cresques) Seamount, with some ecological considerations
The living and dead fauna of Valencia Seamount, a deep promontory in the middle of the Balearic Basin which summit is at ca. 1100m depth, is described by first time based in a rock dredge perfomed in a sedimentary area of the summit Mount. Surface-feeder polychaetes (the Paraonidae Levinsenia gracilis and Terebellidae as dominant), and taxodont bivalves (Ledella messanensis and Yoldiella ovulum) were the main species of benthos. We found alive remains of the bamboo coral Isidella elongata, a vulnerable, habitat-forming species in the deep Mediterranean. Benthos density was low (0.6 organisms/2 dm3 mud). Thanatocoenosis evidenced a rather moderate diversity on benthic bivalves (11 species) and gastropods (9 species) also dominated by surface deposit feeders. Fish (identified/ quantified from sedimented otoliths) showed diversified and abundant mesopelagic fauna, mainly Myctophidae. More interestingly, we highlighted among benthopelagic fish the occurrence of recruits of Merluccius merluccius, Micromesistius poutassou, or Hymenocephalus italicus, all species that live in the neighboring slopes of the Iberian
Peninsula and the Balearic Islands at quite shallower depths (at 100-700 m) than their distribution in the Valencia Seamount summit (1102–1130 m) based on the deposited otoliths found. Some ecological aspects were discussed and the necessity to consider the deep Valencia Seamount as a potential area that should be under protection.En prensa
Habitat use by Gadiculus argenteus (Pisces, Gadidae) in the Galician and Cantabrian Sea waters (NE Atlantic)
Forage fish species play a crucial role in most ecosystems, transferring energy from plankton to larger fishes. Therefore, understanding the factors driving the dynamics of forage fish populations is essential in marine ecosystems. Gadiculus argenteus is an important forage fish species in the Galicia and Cantabrian Sea ecosystem. In this study, the influence of several biotic and abiotic factors on the distribution of this species was examined using generalized additive models in a 2-step approach. G. argenteus habitat preference was not affected by changes in annual abundance during the study period (1998-2019). From the variables selected in the final models, depth and geographic location (latitude and longitude) were the most important factors to describe the presence of G. argenteus. Peak abundance was found on the upper slope and although the species was found throughout the study area, its higher abundance values were located in Galician waters. The species seemed to avoid coarse sand bottoms, with mean chlorophyll a concentration showing a positive effect on the presence and abundance of G. argenteus. Interestingly, the observed aggregations of G. argenteus showed a remarkable similarity to the commercial trawling footprint in the area, suggesting a strong link between the distribution of this forage species and the distribution of its predators, most of which are important commercial species. Further work should focus on a better understanding of this relationship to provide important information on the study of the structure and functioning of the marine ecosystem of the northern Spanish continental shelf.Versión del editor2,48
Demersal and epibenthic communities of sedimentary habitats in the Avilés Canyon System, Cantabrian Sea (NE Atlantic)
The aim of this study was to describe the epibenthic and demersal communities of the Avilés Canyon System (ACS) in relation to the environmental variables that characterize their biotope. ACS (Cantabrian Sea, NE Atlantic) was recently included in the Natura 2000 network as a Site of Community Importance (SCI). Data of faunal biomass derived from 6 surveys carried out using beam trawl and otter trawls in 2009 and 2010 within INDEMARES and ERDEM projects. Data were divided into two groups to obtain information about the two ecological compartments: benthic and demersal. The total number of species used in this analysis ascended to 116 in the case of benthic organisms and 110 in the case of demersal. Hierarchical clustering analysis was applied to obtain groups of samples similar in terms of species composition for the two ecological components. Depth was the main discriminating factor for grouping hauls, showing high consistency of bathymetric range independently from the compartment examined. Six groups were identified by depth as follows: medium shelf (∼100–200 m), external shelf (∼150–300m), shelf break (∼300–400 m), upper-slope (∼500–700 m), upper middle-slope (∼700–1100 m), and lower-middle-slope (1200–1500 m). SIMPER analysis on biomass values was performed to determine the structure of the faunal assemblages observed for each group in both compartments. Using biomass values for the analysis allowed for the exploration of groups playing important roles in ecosystem functioning and energy fluxes taking place on the sedimentary bottom of this SCI. Finally, CCA analysis revealed that the main environmental drivers were depth, broad scale bathymetric position index (BPI), near-bottom salinity, sedimentary type, and dynamics related variables (Q50 phy and So). This study gives an inventory of the soft bottom assemblages along a very wide depth range (100–1500 m) inside a SCI, linking both epibenthic and demersal communities with the biotope preferences. This study contributes to fundamental knowledge on soft-bottom communities as a pre-requisite, necessary for the next steps in terms of management framework in the SCI
Valoración funcional en pacientes intervenidos medianteplastia de LCA con semitendinoso-recto interno y sistema Togglelock.
Introducción: Una de las lesiones más frecuente de la rodilla y que está en aumento, sobre todo en el ámbito deportivo es la lesión del ligamento cruzado anterior. La reconstrucción quirúrgica es fundamental para recuperar la biomecánica de la rodilla, proporcionar una correcta estabilidad y funcionamiento libre de dolor, así como evitar cambios degenerativos tempranos. El objetivo del presente estudio fue valorar la recuperación funcional de los pacientes sometidos a una reconstrucción del ligamento cruzado anterior mediante ligamentoplastia con tendón semitendinoso-recto interno y sistema Toggelock. Material y métodos: Se diseñó un estudio retrospectivo descriptivo observacional, en el que se incluyeron a 29 pacientes a los cuales se les realizó una ligamentoplastia con semitendinoso-recto interno y sistema Togglelock en nuestro Centro, durante los años 2017-2018. Se estudiaron variables obtenidas de la historia clínica y la escala de Lysholm para la valoración del paciente. Resultados: En total, se obtuvo una muestra de 29 pacientes, 26 hombres y 3 mujeres con una media de edad de 31,13 años (rango 19-53). La rodilla más frecuentemente lesionada fue la derecha en 17 pacientes de 29, presentando lesiones asociadas el 65%. Una paciente había sufrido una fractura tibial intervenida con un clavo endomedular que alteró los resultados finales. La puntuación postquirúrgica de la escala de valoración subjetiva de Lysholm fue de 86. La movilidad de la rodilla intervenida presentó una reducción mínima de flexión de 6º en comparación con la rodilla no operada estadísticamente significativa. Conclusión: Los resultados obtenidos tras la reconstrucción del LCA con dicha técnica, utilizando la plastia del semitendinoso-recto interno y sistema Togglelock fueron buenos-excelentes, con un alto grado de satisfacción en los pacientes, escasas complicaciones y con resultados funcionales notables
Differential processing of anthropogenic carbon and nitrogen in benthic food webs of A Coruña (NW Spain) traced by stable isotopes
proyectos ANILE (CTM2009-
08396 and CTM2010-08804-E) del Plan Nacional de I+D+i y RADIALES del
Instituto Español de Oceanografía (IEO). C.M. e I.G.V. disfrutaron de contratos FPI
del IEO y del Ministerio de Economía y Competividad respectivamente.In this study the effect of inputs of organic matter and anthropogenic nitrogen at small spatial scales were investigated in the benthos of the Ria of A Coruña (NW Spain) using stable carbon and nitrogen isotopes. This ria is characteristically enriched in nutrients provided either by marine processes (as coastal upwelling) or by urban and agricultural waste. Stable isotope composition in trophic guilds of infaunal benthos revealed spatial differences related to their nutrient inputs. The main difference was the presence of an additional chemoautotrophic food web at the site with a large accumulation of organic matter. The enrichment in heavy nitrogen isotopes observed in most compartments suggests the influence of sewage-derived nitrogen, despite large inputs of marine nitrogen. Macroalgae (Fucus vesiculosus) resulted significantly enriched at the site influenced by estuarine waters. In contrast, no differences were found in mussels (Mytilus galloprovincialis), thus suggesting a major dependence on marine nutrient sources for this species. However, the estimations of anthropogenic influence were largely dependent on assumptions required to model the different contributions of sources. The measurement of stable isotope signatures in various compartments revealed that, despite anthropogenic nutrients are readily incorporated into local food webs, a major influence of natural marine nutrient sources cannot be discarded.IEO, Plan nacional I+D+iPreprint2,277
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