Feature-rich multiplex lexical networks reveal mental strategies of early language learning

Knowledge in the human mind exhibits a dualistic vector/network nature. Modelling words as vectors is key to natural language processing, whereas networks of word associations can map the nature of semantic memory. We reconcile these paradigms—fragmented across linguistics, psychology and computer science—by introducing FEature-Rich MUltiplex LEXical (FERMULEX) networks. This novel framework merges structural similarities in networks and vector features of words, which can be combined or explored independently. Similarities model heterogenous word associations across semantic/syntactic/phonological aspects of knowledge. Words are enriched with multi-dimensional feature embeddings including frequency, age of acquisition, length and polysemy. These aspects enable unprecedented explorations of cognitive knowledge. Through CHILDES data, we use FERMULEX networks to model normative language acquisition by 1000 toddlers between 18 and 30 months. Similarities and embeddings capture word homophily via conformity, which measures assortative mixing via distance and features. Conformity unearths a language kernel of frequent/polysemous/short nouns and verbs key for basic sentence production, supporting recent evidence of children’s syntactic constructs emerging at 30 months. This kernel is invisible to network core-detection and feature-only clustering: It emerges from the dual vector/network nature of words. Our quantitative analysis reveals two key strategies in early word learning. Modelling word acquisition as random walks on FERMULEX topology, we highlight non-uniform filling of communicative developmental inventories (CDIs). Biased random walkers lead to accurate (75%), precise (55%) and partially well-recalled (34%) predictions of early word learning in CDIs, providing quantitative support to previous empirical findings and developmental theories

Biomimetic Sonar for Electrical Activation of the Auditory Pathway

Relying on the mechanism of bat’s echolocation system, a bioinspired electronic device has been developed to investigate the cortical activity of mammals in response to auditory sensorial stimuli. By means of implanted electrodes, acoustical information about the external environment generated by a biomimetic system and converted in electrical signals was delivered to anatomically selected structures of the auditory pathway. Electrocorticographic recordings showed that cerebral activity response is highly dependent on the information carried out by ultrasounds and is frequency-locked with the signal repetition rate. Frequency analysis reveals that delta and beta rhythm content increases, suggesting that sensorial information is successfully transferred and integrated. In addition, principal component analysis highlights how all the stimuli generate patterns of neural activity which can be clearly classified. The results show that brain response is modulated by echo signal features suggesting that spatial information sent by biomimetic sonar is efficiently interpreted and encoded by the auditory system. Consequently, these results give new perspective in artificial environmental perception, which could be used for developing new techniques useful in treating pathological conditions or influencing our perception of the surroundings

Colchicine in managing skin conditions. a systematic review

(1) Background: Colchicine is a natural alkaloid with anti-inflammatory properties used to treat various disorders, including some skin diseases. This paper aims to incorporate all the available studies proposing colchicine as a treatment alternative in the management of cutaneous conditions. (2) Methods: In this systematic review, the available articles present in various databases (PubMed, Scopus-Embase, and Web of Science), proposing colchicine as a treatment for cutaneous pathological conditions, have been selected. Exclusion criteria included a non-English language and non-human studies. (3) Results: Ninety-six studies were included. Most of them were case reports and case series studies describing colchicine as single therapy, or in combination with other drugs. Hidradenitis suppurativa, pyoderma gangrenosum, erythema nodosum, erythema induratum, storage diseases, perforating dermatosis, bullous diseases, psoriasis, vasculitis, acne, urticaria, stomatitis, actinic keratosis, and pustular dermatosis were the main diseases discussed in literature. Although the therapeutic outcomes were variable, most of the studies reported, on average, good clinical results (4) Conclusions: Colchicine could be, as a single therapy or in combination with other drugs, a possible treatment to manage several skin diseases

Everolimus improves memory and learning while worsening depressive- and anxiety-like behavior in an animal model of depression

Everolimus (EVR) is an orally-administered rapamycin analog that selectively inhibits the mammalian target of rapamycin (mTOR) kinase (mainly mTORC1 and likely mTORC2) and the related signaling pathway. mTOR is a serine/threonine protein kinase regulating multiple important cellular functions; dysfunction of mTOR signaling has also been implicated in the pathophysiology of several neurological, neurodegenerative, developmental and cognitive disorders. EVR is widely used as an anti-neoplastic therapy and more recently in children with tuberous sclerosis complex (TSC). However, no clear correlation exists between EVR use and development of central side effects e.g. depression, anxiety or cognitive impairment. We studied the effects of a 3 weeks administration of EVR in mice chronically treated with betamethasone 21-phosphate disodium (BTM) as a model of depression and cognitive decline. EVR treatment had detrimental effects on depressive- and anxiety-like behavior while improving cognitive performance in both control (untreated) and BTM-treated mice. Such effects were accompanied by an increased hippocampal neurogenesis and synaptogenesis. Our results therefore might support the proposed pathological role of mTOR dysregulation in depressive disorders and confirm some previous data on the positive effects of mTOR inhibition in cognitive decline. We also show that EVR, possibly through mTOR inhibition, may be linked to the development of anxiety. The increased hippocampal neurogenesis by EVR might explain its ability to improve cognitive function or protect from cognitive decline. Our findings suggest some caution in the use of EVR, particularly in the developing brain; patients should be carefully monitored for their psychiatric/neurological profiles in any clinical situation where an mTOR inhibitor and in particular EVR is used e.g. cancer treatment, TSC or immunosuppression

Image processing applications: From particle physics to society

We present an embedded system for extremely efficient real-time pattern recognition execution, enabling technological advancements with both scientific and social impact. It is a compact, fast, low consumption processing unit (PU) based on a combination of Field Programmable Gate Arrays (FPGAs) and the full custom associative memory chip. The PU has been developed for real time tracking in particle physics experiments, but delivers flexible features for potential application in a wide range of fields. It has been proposed to be used in accelerated pattern matching execution for Magnetic Resonance Fingerprinting (biomedical applications), in real time detection of space debris trails in astronomical images (space applications) and in brain emulation for image processing (cognitive image processing). We illustrate the potentiality of the PU for the new applications

Design, construction, and test of the Gas Pixel Detectors for the IXPE mission

Due to be launched in late 2021, the Imaging X-Ray Polarimetry Explorer (IXPE) is a NASA Small Explorer mission designed to perform polarization measurements in the 2-8 keV band, complemented with imaging, spectroscopy and timing capabilities. At the heart of the focal plane is a set of three polarization-sensitive Gas Pixel Detectors (GPD), each based on a custom ASIC acting as a charge-collecting anode. In this paper we shall review the design, manufacturing, and test of the IXPE focal-plane detectors, with particular emphasis on the connection between the science drivers, the performance metrics and the operational aspects. We shall present a thorough characterization of the GPDs in terms of effective noise, trigger efficiency, dead time, uniformity of response, and spectral and polarimetric performance. In addition, we shall discuss in detail a number of instrumental effects that are relevant for high-level science analysis -- particularly as far as the response to unpolarized radiation and the stability in time are concerned.Comment: To be published in Astroparticle Physic

The ATLAS fast tracKer system

The ATLAS Fast TracKer (FTK) was designed to provide full tracking for the ATLAS high-level trigger by using pattern recognition based on Associative Memory (AM) chips and fitting in high-speed field programmable gate arrays. The tracks found by the FTK are based on inputs from all modules of the pixel and silicon microstrip trackers. The as-built FTK system and components are described, as is the online software used to control them while running in the ATLAS data acquisition system. Also described is the simulation of the FTK hardware and the optimization of the AM pattern banks. An optimization for long-lived particles with large impact parameter values is included. A test of the FTK system with the data playback facility that allowed the FTK to be commissioned during the shutdown between Run 2 and Run 3 of the LHC is reported. The resulting tracks from part of the FTK system covering a limited η-ϕ region of the detector are compared with the output from the FTK simulation. It is shown that FTK performance is in good agreement with the simulation. © The ATLAS collaboratio