Molecular Hydrogen in the FUSE Translucent Lines of Sight: The Full Sample

We report total abundances and related parameters for the full sample of the FUSE survey of molecular hydrogen in 38 translucent lines of sight. New results are presented for the "second half" of the survey involving 15 lines of sight to supplement data for the first 23 lines of sight already published. We assess the correlations between molecular hydrogen and various extinction parameters in the full sample, which covers a broader range of conditions than the initial sample. In particular, we are now able to confirm that many, but not all, lines of sight with shallow far-UV extinction curves and large values of the total-to-selective extinction ratio, $R_V$ = $A_V$ / $E(B-V)$ -- characteristic of larger than average dust grains -- are associated with particularly low hydrogen molecular fractions ($f_{\rm H2}$). In the lines of sight with large $R_V$, there is in fact a wide range in molecular fractions, despite the expectation that the larger grains should lead to less H$_2$ formation. However, we see specific evidence that the molecular fractions in this sub-sample are inversely related to the estimated strength of the UV radiation field and thus the latter factor is more important in this regime. We have provided an update to previous values of the gas-to-dust ratio, $N$(H$_{\rm tot}$)/$E(B-V)$, based on direct measurements of $N$(H$_2$) and $N$(H I). Although our value is nearly identical to that found with Copernicus data, it extends the relationship by a factor of 2 in reddening. Finally, as the new lines of sight generally show low to moderate molecular fractions, we still find little evidence for single monolithic "translucent clouds" with $f_{\rm H2}$ $\sim$ 1.Comment: 35 pages, 5 tables, 7 figures, accepted for publication in The Astrophysical Journal Supplements Serie

The MNI data-sharing and processing ecosystem

AbstractNeuroimaging has been facing a data deluge characterized by the exponential growth of both raw and processed data. As a result, mining the massive quantities of digital data collected in these studies offers unprecedented opportunities and has become paramount for today's research. As the neuroimaging community enters the world of “Big Data”, there has been a concerted push for enhanced sharing initiatives, whether within a multisite study, across studies, or federated and shared publicly. This article will focus on the database and processing ecosystem developed at the Montreal Neurological Institute (MNI) to support multicenter data acquisition both nationally and internationally, create database repositories, facilitate data-sharing initiatives, and leverage existing software toolkits for large-scale data processing

Supplementary_Revised

eMethods, eTables (Table e1, Table e2, Table e3, Table e4), eFigures (Figure e1, Figure e2), eReferences (1

A Far Ultraviolet Spectroscopic Explorer Survey of Interstellar Molecular Hydrogen in Translucent Clouds

International audienceWe report the first ensemble results from the Far Ultraviolet Spectroscopic Explorer survey of molecular hydrogen in lines of sight with AV>~1 mag. We have developed techniques for fitting computed profiles to the low-J lines of H2, and thus determining column densities for J=0 and J=1, which contain >~99% of the total H2. From these column densities and ancillary data we have derived the total H2 column densities, hydrogen molecular fractions, and kinetic temperatures for 23 lines of sight. This is the first significant sample of molecular hydrogen column densities of ~1021 cm-2, measured through UV absorption bands. We have also compiled a set of extinction data for these lines of sight, which sample a wide range of environments. We have searched for correlations of our H2-related quantities with previously published column densities of other molecules and extinction parameters. We find strong correlations between H2 and molecules such as CH, CN, and CO, in general agreement with predictions of chemical models. We also find the expected correlations between hydrogen molecular fraction and various density indicators such as kinetic temperature, CN abundance, the steepness of the far-UV extinction rise, and the width of the 2175 Å bump. Despite the relatively large molecular fractions, we do not see the values greater than 0.8 expected in translucent clouds. With the exception of a few lines of sight, we see little evidence for the presence of individual translucent clouds in our sample. We conclude that most of the lines of sight are actually composed of two or more diffuse clouds similar to those found toward targets like ζ Oph. We suggest a modification in terminology to distinguish between a ``translucent line of sight'' and a ``translucent cloud.'

The Cuban Human Brain Mapping Project, a young and middle age population-based EEG, MRI, and cognition dataset

Measurement(s) functional brain measurement Technology Type(s) electroencephalography (EEG) • magnetic resonance imaging (MRI) • neuropsychological testing Factor Type(s) age of participants • gender of participants • handedness of participants • educational level of participants Sample Characteristic - Organism Homo sapiens Sample Characteristic - Location Cuba Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.1327734

Proceedings of the OHBM Brainhack 2021

The global pandemic presented new challenges and op-portunities for organizing conferences, and OHBM 2021was no exception. The OHBM Brainhack is an event thatoccurs just prior to the OHBM meeting, typically in-per-son, where scientists of all levels of expertise and interestgather to work and learn together for a few days in a col-laborative hacking-style environment on projects of com-mon interest (1). Building off the success of the OHBM2020 Hackathon (2), the 2021 Open Science SpecialInterest Group came together online to organize a largecoordinated Brainhack event that would take place overthe course of 4 days. The OHBM 2021 Brainhack eventwas organized along two guiding principles, providinga highly inclusive collaborative environment for inter-action between scientists across disciplines and levelsof expertise to push forward important projects thatneed support, also known as the “Hack-Track” of theBrainhack. The second aim of the OHBM Brainhack is toempower scientists to improve the quality of their sci-entific endeavors by providing high-quality hands-ontraining on best practices in open-science approaches.This is best exemplified by the training events providedby the “Train-Track” at the OHBM 2021 Brainhack. Here,we briefly explain both of these elements of the OHBM2021 Brainhack, before continuing on to the Brainhackproceedings