1,722,869 research outputs found
Loffredo V., Torromino G., Esposito F., Carboncino A., Cecere A., Mele A., De Leonibus E. "Sex regulates memory capacity"
No full textMemory Capacity (MC) is the number of information maintained in memory. MC is regulated by fronto-striatal dopamine circuit and hippocampus (HP).
Using a modified version of the object recognition task, the DOT/IOT, we have recently showed that adult naïve male mice could discriminate 3,4,6 but not 9 different objects after a 1 min or 24 hrs delay. Moreover, it has been reported that male mice use the HP, as well as humans, to solve the task (Sannino et al 2012, Olivito et al 2014; Sugita et al 2015).
To report sex differences influencing MC, we have challenged 3 months old mice (males and females) with the 6-DOT (highest memory load), testing them at different time points.
We have found that 3 months old female mice properly perform the 6-DOT when tested at 1 min delay (Short Term Memory, STM), but they are impaired when tested 24 hr later (Long Term Memory, LTM). Female mice properly perform the 6-IOT (lowest memory load) independently on the delay.
We hypothesized that the impairment in LTM could reflect sex regulated differences in the use of different neuronal circuits to solve the task. Therefore, we are performing c-fos immunohistochemical analysis as an index of stimuli-induced neuronal activation on the HP and the prefrontal cortex, at different time points after exposing the animals to the 6-DOT. Preliminary data show that female mice, differently from males, do not activate the HP.
Sex-regulated neuronal activation might be relevant to understand the higher impact of dementia in women as compared to men
Unsupervised author identification and characterization
No full textAuthor identification is a hot topic, especially in the Internet age. Following our previous work in which we proposed a novel approach to this problem, based on relational representations that take into account the structure of sentences, here we present a tool that computes and visualizes a numerical and graphical characterization of the authors/texts based on several linguistic features. This tool, that extends a previous language analysis tool, is the ideal complement to the author identification technique, that is based on a clustering procedure whose outcomes (i.e., the authors’ models) are not human-readable. Both approaches are unsupervised, which allows them to tackle problems to which other state-of-the-art systems are not applicable
A Review on Initialization Methods for Nonnegative Matrix Factorization: Towards Omics Data Experiments
No full textNonnegative Matrix Factorization (NMF) has acquired a relevant role in the panorama of knowledge extraction, thanks to the peculiarity that non-negativity applies to both bases and weights, which allows meaningful interpretations and is consistent with the natural human part-based learning process. Nevertheless, most NMF algorithms are iterative, so initialization methods affect convergence behaviour, the quality of the final solution, and NMF performance in terms of the residual of the cost function. Studies on the impact of NMF initialization techniques have been conducted for text or image datasets, but very few considerations can be found in the literature when biological datasets are studied, even though NMFs have largely demonstrated their usefulness in better understanding biological mechanisms with omic datasets. This paper aims to present the state-of-the-art on NMF initialization schemes along with some initial considerations on the impact of initialization methods when microarrays (a simple instance of omic data) are evaluated with NMF mechanisms. Using a series of measures to qualitatively examine the biological information extracted by a given NMF scheme, it preliminary appears that some information (e.g., represented by genes) can be extracted regardless of the initialization scheme used
Practicing ethnography in migration-related detention centers: A reflexive account
Full text linkFeminist scholars, as well as community psychologists, have advocated the role of reflexive engagement in the research process in order to challenge power relations. Moreover, the liberating potential of storytelling, especially when working with issues of diversity and marginalization, has been stressed. The purpose of this article is to reflect on an ethnographic work underway in the Identification and Expulsion Center-CIE of Ponte Galeria, Rome. How the researcher's identities, values, and experiences, alongside power and privilege, have influenced her positioning in the research setting and the relationships formed with the different setting members is the subject of discussion. In sharing the story of this work, the final intent is to contribute to the joint effort to foster a reflexive community psychology practice incorporating feminist goals and a dialogue about ethnography in community psychology.Fundação para a Ciência e a Tecnologia (FCT)info:eu-repo/semantics/publishedVersio
GENDER, VIOLENCE AND REGIMES OF VULNERABILITY IN IMMIGRATION DETENTION: A Transnational Analysis
No full textThis chapter examines the gendered, racialised and classed constructions that are deeply embedded in the fabric of everyday life in immigration detention centres in Italy, Portugal and the UK, and the ways they underpin hierarchies of vulnerability and deservingness. Drawing on traditions of Black feminist thought, it uses testimonies from detained women, staff and human rights workers to explore how gendered violence is conceptualised and addressed in these sites. Notwithstanding their difficult experiences, women who are detained attempt to reject their treatment. In foregrounding their accounts and embodied experiences, this chapter seeks to contribute to a feminist abolitionist critique of immigration detention, grounded in a recognition of the ways that immigration detention reproduces violence
Neuronal Networks Observed with Resting State Functional Magnetic Resonance Imaging in Clinical Populations
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
