Relationships between interlibrary loan and research activity in Canada

Interlibrary Loan borrowing rates in academic libraries are influenced by an array of factors. This article explores the relationship between interlibrary loan borrowing activity and research activity at 42 Canadian academic institutions. A significant positive correlation was found between interlibrary loan borrowing activity and measures of research activity. The degree of correlation observed depended on the category of institution, with undergraduate and comprehensive universities showing the largest correlations. This is the first study to quantify the relationship between interlibrary loan and research activity, and the findings suggest that interlibrary loan plays a role in supporting academic research at Canadian universities

An analysis of direct reciprocal borrowing among Québec university libraries

An analysis of Quebec academic libraries’ direct reciprocal borrow- ´ ing statistics from 2005 to 2010 reveals that the physical distance separating universities plays an important role in determining the amount of direct reciprocal borrowing activity conducted between institutions. Significant statistical correlations were also seen between the amount of direct reciprocal borrowing/lending as well as institution size and library collection size. Given their proximity, Montreal-area libraries have a higher ratio of direct reciprocal bor- ´ rowing activity compared to interlibrary loan consortial borrowing activity, whereas libraries located outside of Montreal have higher ´ interlibrary loan activity compared to direct reciprocal borrowing. It was found that institutions’ net lender and borrower status can shift depending on whether one is looking at direct reciprocal borrowing versus interlibrary loan activity. An exploratory social network analysis of direct reciprocal borrowing among Quebec ´ academic libraries was performed, and it affirmed the important role of physical distance in determining direct reciprocal borrowing activity. Language may also play a role in affecting the amount of direct reciprocal borrowing

The type III neurofilament peripherin is expressed in the tuberomammillary neurons of the mouse

<p>Abstract</p> <p>Background</p> <p>Peripherin, a type III neuronal intermediate filament, is widely expressed in neurons of the peripheral nervous system and in selected central nervous system hindbrain areas with projections towards peripheral structures, such as cranial nerves and spinal cord neurons. Peripherin appears to play a role in neurite elongation during development and axonal regeneration, but its exact function is not known. We noticed high peripherin expression in the posterior hypothalamus of mice, and decided to investigate further the exact location of expression and function of peripherin in the mouse posterior hypothalamus.</p> <p>Results</p> <p><it>In situ </it>hybridization indicated expression of peripherin in neurons with a distribution reminiscent of the histaminergic neurons, with little signal in any other part of the forebrain. Immunocytochemical staining for histidine decarboxylase and peripherin revealed extensive colocalization, showing that peripherin is produced by histaminergic neurons in all parts of the tuberomammillary nucleus. We next used histamine immunostaining in peripherin knockout, overexpressing and wild type mice to study if altered peripherin expression affects these neurons, but could not detect any visible difference in the appearance of these neurons or their axons.</p> <p>Peripherin knockout mice and heterozygotic littermates were used for measurement of locomotor activity, feeding, drinking, and energy expenditure. Both genotypes displayed diurnal rhythms with all the parameters higher during the dark period. The respiratory quotient, an indicator of the type of substrate being utilized, also exhibited a significant diurnal rhythm in both genotypes. The diurnal patterns and the average values of all the recorded parameters for 24 h, daytime and night time were not significantly different between the genotypes, however.</p> <p>Conclusion</p> <p>In conclusion, we have shown that peripherin is expressed in the tuberomammillary neurons of the mouse hypothalamus. Monitoring of locomotor activity, feeding, drinking, and energy expenditure in mice either lacking or overexpressing peripherin did not reveal any difference, so the significance of peripherin in these neurons remains to be determined. The complete overlap between histidine decarboxylase and peripherin, both the protein and its mRNA, renders peripherin a useful new marker for histaminergic neurons in the hypothalamus.</p

Anatomical and microstructural determinants of hippocampal subfield functional connectome embedding

The hippocampus plays key roles in cognition and affect and serves as a model system for structure/function studies in animals. So far, its complex anatomy has challenged investigations targeting its substructural organization in humans. State-of-the-art MRI offers the resolution and versatility to identify hippocampal subfields, assess its microstructure, and study topographical principles of its connectivity in vivo. We developed an approach to unfold the human hippocampus and examine spatial variations of intrinsic functional connectivity in a large cohort of healthy adults. In addition to mapping common and unique connections across subfields, we identified two main axes of subregional connectivity transitions. An anterior/posterior gradient followed long-axis landmarks and metaanalytical findings from task-based functional MRI, while a medial/lateral gradient followed hippocampal infolding and correlated with proxies of cortical myelin. Findings were consistent in an independent sample and highly stable across resting-state scans. Our results provide robust evidence for long-axis specialization in the resting human hippocampus and suggest an intriguing interplay between connectivity and microstructure

BrainStat: A toolbox for brain-wide statistics and multimodal feature associations

Analysis and interpretation of neuroimaging datasets has become a multidisciplinary endeavor, relying not only on statistical methods, but increasingly on associations with respect to other brain-derived features such as gene expression, histological data, and functional as well as cognitive architectures. Here, we introduce BrainStat - a toolbox for (i) univariate and multivariate linear models in volumetric and surface-based brain imaging datasets, and (ii) multidomain feature association of results with respect to spatial maps of post-mortem gene expression and histology, task-based fMRI meta-analysis, as well as resting-state fMRI motifs across several common surface templates. The combination of statistics and feature associations into a turnkey toolbox streamlines analytical processes and accelerates cross-modal research. The toolbox is implemented in both Python and MATLAB, two widely used programming languages in the neuroimaging and neuroinformatics communities. BrainStat is openly available and complemented by an expandable documentation

A small world of citations? The influence of collaboration networks on citation practices

This paper examines the proximity of authors to those they cite using degrees of separation in a co-author network, essentially using collaboration networks to expand on the notion of self-citations. While the proportion of direct self-citations (including co-authors of both citing and cited papers) is relatively constant in time and across specialties in the natural sciences (10% of citations) and the social sciences (20%), the same cannot be said for citations to authors who are members of the co-author network. Differences between fields and trends over time lie not only in the degree of co-authorship which defines the large-scale topology of the collaboration network, but also in the referencing practices within a given discipline, computed by defining a propensity to cite at a given distance within the collaboration network. Overall, there is little tendency to cite those nearby in the collaboration network, excluding direct self-citations. By analyzing these social references, we characterize the social capital of local collaboration networks in terms of the knowledge production within scientific fields. These results have implications for the long-standing debate over biases common to most types of citation analysis, and for understanding citation practices across scientific disciplines over the past 50 years. In addition, our findings have important practical implications for the availability of 'arm's length' expert reviewers of grant applications and manuscripts

Convergence of cortical types and functional motifs in the human mesiotemporal lobe

The mesiotemporal lobe (MTL) is implicated in many cognitive processes, is compromised in numerous brain disorders, and exhibits a gradual cytoarchitectural transition from six-layered parahippocampal isocortex to three-layered hippocampal allocortex. Leveraging an ultra-high-resolution histological reconstruction of a human brain, our study showed that the dominant axis of MTL cytoarchitectural differentiation follows the iso-to-allocortical transition and depth-specific variations in neuronal density. Projecting the histology-derived MTL model to in-vivo functional MRI, we furthermore determined how its cytoarchitecture underpins its intrinsic effective connectivity and association to large-scale networks. Here, the cytoarchitectural gradient was found to underpin intrinsic effective connectivity of the MTL, but patterns differed along the anterior-posterior axis. Moreover, while the iso-to-allocortical gradient parametrically represented the multiple-demand relative to task-negative networks, anterior-posterior gradients represented transmodal versus unimodal networks. Our findings establish that the combination of micro- and macrostructural features allow the MTL to represent dominant motifs of whole-brain functional organisation

A multi-scale cortical wiring space links cellular architecture and functional dynamics in the human brain.

The vast net of fibres within and underneath the cortex is optimised to support the convergence of different levels of brain organisation. Here, we propose a novel coordinate system of the human cortex based on an advanced model of its connectivity. Our approach is inspired by seminal, but so far largely neglected models of cortico-cortical wiring established by postmortem anatomical studies and capitalises on cutting-edge in vivo neuroimaging and machine learning. The new model expands the currently prevailing diffusion magnetic resonance imaging (MRI) tractography approach by incorporation of additional features of cortical microstructure and cortico-cortical proximity. Studying several datasets and different parcellation schemes, we could show that our coordinate system robustly recapitulates established sensory-limbic and anterior-posterior dimensions of brain organisation. A series of validation experiments showed that the new wiring space reflects cortical microcircuit features (including pyramidal neuron depth and glial expression) and allowed for competitive simulations of functional connectivity and dynamics based on resting-state functional magnetic resonance imaging (rs-fMRI) and human intracranial electroencephalography (EEG) coherence. Our results advance our understanding of how cell-specific neurobiological gradients produce a hierarchical cortical wiring scheme that is concordant with increasing functional sophistication of human brain organisation. Our evaluations demonstrate the cortical wiring space bridges across scales of neural organisation and can be easily translated to single individuals