D1 receptor in interneurons of macaque prefrontal cortex: distribution and subcellular localization

Working memory performance is influenced by dopamine activation of D1 family dopamine receptors in the prefrontal cortex; working memory performance is maximal at moderate stimulation of D1 family receptors and is reduced by either higher or lower levels of D1 stimulation. The neuronal mechanisms that underlie this complex relationship are not yet understood. Previous work from this laboratory has demonstrated that the D1 family receptors, D1 and D5, are located in different compartments of pyramidal cells. Here we use an antibody specific to the D1 receptor and double-label immunohistochemistry at the light and electron microscopic level to demonstrate that D1-like immunoreactivity (D1-LIR) is also present in interneurons. D1 receptor is prevalent in parvalbumin-containing interneurons and is less common in calretinin-containing interneurons. At the ultrastructural level, D1-LIR is found associated with the Golgi apparatus and endoplasmic reticulum in the soma, with the membranes of vesicles in proximal dendrites, and with the plasma membrane on distal dendrites, where it is often located near asymmetric synapses. In addition, D1-LIR is also seen in presynaptic axon terminals, which give rise to symmetric synapses onto dendritic shafts and soma. These results raise the possibility that the circuit basis of working memory in the prefrontal cortex involves a D1-mediated inhibitory component.     

Searching for motifs in the behaviour of larval Drosophila melanogaster and Caenorhabditis elegans reveals continuity between behavioural states

We present a novel method for the unsupervised discovery of behavioural motifs in larval Drosophila melanogaster and Caenorhabditis elegans. A motif is defined as a particular sequence of postures that recurs frequently. The animal''s changing posture is represented by an eigenshape time series, and we look for motifs in this time series. To find motifs, the eigenshape time series is segmented, and the segments clustered using spline regression. Unlike previous approaches, our method can classify sequences of unequal duration as the same motif. The behavioural motifs are used as the basis of a probabilistic behavioural annotator, the eigenshape annotator (ESA). Probabilistic annotation avoids rigid threshold values and allows classification uncertainty to be quantified. We apply eigenshape annotation to both larval Drosophila and C. elegans and produce a good match to hand annotation of behavioural states. However, we find many behavioural events cannot be unambiguously classified. By comparing the results with ESA of an artificial agent''s behaviour, we argue that the ambiguity is due to greater continuity between behavioural states than is generally assumed for these organisms.     

Indoor air quality and the associated health risk in primary school buildings in Central Europe – The InAirQ study

The indoor air quality (IAQ) was investigated in sixty-four primary school buildings in five Central European countries (Czech Republic, Hungary, Italy, Poland, and Slovenia). The concentration of volatile organic compounds, aldehydes, PM_2.5 mass, carbon dioxide, radon, as well as physical parameters were investigated during the heating period of 2017/2018. Significant differences were identified for the majority of the investigated IAQ parameters across the countries. The median indoor/outdoor ratios varied considerably. A comprehensive evaluation of IAQ in terms of potential health effects and comfort perception was performed. Hazard quotient values were below the threshold value of 1 with one exception. In contrast, 31% of the school buildings were characterized by hazard index values higher than 1. The maximum cumulative ratio approach highlighted that the concern for non-carcinogenic health effects was either low or the health risk was driven by more substances. The median excess lifetime cancer risk values exceeded the acceptable value of 1 × 10⁻⁶ in the case of radon and formaldehyde. PM_2.5 mass concentration values exceeded the 24 h and annual guideline values set by the World Health Organization in 56 and 85% of the cases, respectively. About 80% of the schools could not manage to comply with the recommended concentration value for carbon dioxide (1000 ppm).