Brain development requires precise orchestration of cellular events through the coordinate exchange of information between distally located cells. One mechanism by which intercellular communication ...is achieved is through the transfer of extracellular vesicles (EVs). Exosomes are EVs that carry lipids, nucleic acids, and proteins and are detectable in most biological fluids including cerebrospinal fluid (CSF). Here we report that CSF EV concentrations undergo age dependent fluctuations. We characterized EV RNA content by next generation small RNA sequencing and miRNA microarray analysis and identified a temporal shift in CSF EV content. CSF EVs encapsulated miRNAs that contain a conserved hnRNPA2/B1 recognition sequence. We found that hnRNPA2/B1-containing EVs were produced by choroid plexus epithelial cells and that hnRNPA2/B1 containing EVs decreased with age. These results provide insight into EV exchange of miRNAs within the central nervous system and a framework to understand how changes in EVs may have an important impact on brain development.
The analysis presented in this paper verifies which of the mixing rules are best for real components of interstellar dust in possible wide range of wavelengths. The Discrete Dipole Approximation ...(DDA) method with elements of different components with various volume fractions has been used. We have considered six materials: ice, amorphous carbon, graphite, SiC, silicates and iron; and the following mixing rules: Maxwell-Garnett, Bruggeman, Looyenga, Hanay and Lichtenecker, which must satisfy rigorous bounds. The porous materials have also been considered. We have assumed simplified spatial distribution, shape and size of inclusions. The criteria given by Draine have been used to determine the range of wavelengths for the considered mixtures in order to calculate the Qext using the DDA. From all the chosen mixing rules for the examined materials in majority of cases (13 out of 20), the best results have been obtained using the Lichtenecker mixing rule. In five cases, this rule is better for some volume fraction of inclusions.
•We evaluated saccade, pursuit and fixation ocular motor profiles in ADHD.•Key difficulties relating to saccade inhibition were identified for ADHD.•Other difficulties related to memorizing visual ...target locations and initiating antisaccades.•These findings highlight potential ocular motor biomarkers for ADHD.
Atypical motor coordination and cognitive processes, such as response inhibition and working memory, have been extensively researched in individuals with attention deficit hyperactivity disorder (ADHD). Oculomotor neural circuits overlap extensively with regions involved in motor planning and cognition, therefore studies of oculomotor function may offer unique insights into motor and cognitive control in ADHD. We performed a series of pairwise meta-analyses based on data from 26 oculomotor studies in ADHD to examine whether there were differences in performance on visually-guided saccade, gap, antisaccade, memory-guided, pursuit eye movements and fixation tasks. These analyses revealed oculomotor disturbances in ADHD, particularly for difficulties relating to saccade inhibition, memorizing visual target locations and initiating antisaccades. There was no evidence for pursuit eye movement disturbances or saccade dysmetria. Investigating oculomotor abnormalities in ADHD may provide insight into top-down cognitive control processes and motor control, and may serve as a promising biomarker in ADHD research and clinical practice.
We present the computation of effective refractive coefficients for inhomogeneous two-component grains with three kinds of inclusions with mincl= 3.0 + 4.0i, 2.0 + 1.0i, 2.5 + 0.0001i and a matrix ...with mm= 1.33 + 0.01i for 11 volume fractions of inclusions from 0 to 50 per cent and wavelengths λ= 0.5, 1.0, 2.0 and 5.0 μm. The coefficients of extinction for these grains have been computed using a discrete dipole approximation. Computation of the extinction by the same method for grains composed of a matrix material with randomly embedded inclusions has been carried out for different volume fractions of inclusions. A comparison of extinction coefficients obtained for both models of grain material allows one to choose the best mixing rule for a mixture. In cases of inclusions with mincl= 2.0 + 1.0i and 2.5 + 0.0001i the best fit for the whole wavelength range and volume fractions of inclusions from 0 to 50 per cent has been obtained for the Lichtenecker mixing rule. In the case of mincl= 3.0 + 4.0i the fit for the whole wavelength range and volume fractions of inclusions from 0 to 50 per cent is not very significant but the best fit has been obtained for the Hanai rule. For volume fractions of inclusions from 0 to 15 per cent a very good fit has been obtained for the whole wavelength range for Rayleigh and Maxwell-Garnett mixing rules.
: Return migration has escaped significant analysis in the Pacific island region. Both migration from and return migration to the Tongan village of Nukunuku are for multiple reasons, with migration ...centred on employment and education, and return centred on the social context of home and duty. Return is limited, with intentions not being matched with practice, and the village and national population not growing. However, return migrants acquire skills, capital and experience overseas, which can be transferred into a Tongan cultural context, although identities have changed during migration. Return migrants typically take up employment or acquire businesses on return, gain some social status from the outcome, and are neither failures nor retirees. Nonetheless, return engenders expectations and tensions exist between returnees and more established residents, although ultimately, return migrants contribute to household, local and national development, as part of an unfinished process.
Brain development requires precise orchestration of cellular events through the coordinate exchange of information between distally located cells. One mechanism by which intercellular communication ...is achieved is through the transfer of extracellular vesicles (EVs). Exosomes are EVs that carry lipids, nucleic acids, and proteins and are detectable in most biological fluids including cerebrospinal fluid (CSF). Here we report that CSF EV concentrations undergo age dependent fluctuations. We characterized EV RNA content by next generation small RNA sequencing and miRNA microarray analysis and identified a temporal shift in CSF EV content. CSF EVs encapsulated miRNAs that contain a conserved hnRNPA2/B1 recognition sequence. We found that hnRNPA2/B1-containing EVs were produced by choroid plexus epithelial cells and that hnRNPA2/B1 containing EVs decreased with age. These results provide insight into EV exchange of miRNAs within the central nervous system and a framework to understand how changes in EVs may have an important impact on brain development.
When are array processors cost effective? How do they stack up against the supercomputers? This analysis weighs the many factors involved in answering these questions.
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