146 research outputs found

    Cross correlations of the American baby names

    Full text link
    The quantitative description of cultural evolution is a challenging task. The most difficult part of the problem is probably to find the appropriate measurable quantities that can make more quantitative such evasive concepts as, for example, dynamics of cultural movements, behavior patterns and traditions of the people. A strategy to tackle this issue is to observe particular features of human activities, i.e. cultural traits, such as names given to newborns. We study the names of babies born in the United States of America from 1910 to 2012. Our analysis shows that groups of different correlated states naturally emerge in different epochs, and we are able to follow and decrypt their evolution. While these groups of states are stable across many decades, a sudden reorganization occurs in the last part of the twentieth century. We think that this kind of quantitative analysis can be possibly extended to other cultural traits: although databases covering more than one century (as the one we used) are rare, the cultural evolution on shorter time scales can be studied thanks to the fact that many human activities are usually recorded in the present digital era.Comment: submitted for consideration to PNA

    Triazolilideni funzionalizzati come versatili carbeni mesoionici in complessi luminescenti

    Get PDF
    1,2,3-Triazolylidenes belong to the class of abnormal N-heterocyclic carbenes, which are singlet carbenes with the carbonic center directly bound to at least one nitrogen atom of the heterocycle, and no uncharged resonance structure can be drawn. Since their precursors synthesis is quite simple and it allows the variation of the substituents on the triazolic ring, the use of 1,2,3-triazolylidenes as bidentate ligands for appropriate metallic complexes is very interesting. In the present work I report the synthesis of 1,2,3-triazolium salts 1-benzyl-3-methyl-4-(pyridin-2-yl)-1H-1,2,3-triazol-3-ium (L1-X), 3-methyl-1-phenyl-4-(pyridin-2-yl)-1H-1,2,3-triazol-3-ium (L2-X) (X=OTf, I) and 1,1'-dibenzyl-3-methyl-1H,1'H-[4,4'-bi(1,2,3-triazol)]-3-ium iodide (L3-I), that after the formation of the corresponding triazolylidenes have been employed as bidentate ancillary ligands for the synthesis of three cationic Ir(III) complexes (A-BF4, B-BF4 e C-BF4) and a neutral one (D). The synthetized complexes were characterized with NMR spectroscopy, and DFT computational calculations have been performed to compare, once photophysical characterization has been made, the obtained results with experimental measures

    Reassessment of gadolinium odd isotopes neutron cross sections: scientific motivations and sensitivity-uncertainty analysis on LWR fuel assembly criticality calculations

    Get PDF
    Gadolinium odd isotopes cross sections are crucial in assessing the neutronic performance and safety features of a light water reactor (LWR) core. Accurate evaluations of the neutron capture behavior of gadolinium burnable poisons are necessary for a precise estimation of the economic gain due to the extension of fuel life, the residual reactivity penalty at the end of life, and the reactivity peak for partially spent fuel for the criticality safety analysis of Spent Fuel Pools. Nevertheless, present gadolinium odd isotopes neutron cross sections are somehow dated and poorly investigated in the high sensitivity thermal energy region and are available with an uncertainty which is too high in comparison to the present day typical industrial standards and needs. This article shows how the most recent gadolinium cross sections evaluations appear inadequate to provide accurate criticality calculations for a system with gadolinium fuel pins. In this article, a sensitivity and uncertainty analysis (S/U) has been performed to investigate the effect of gadolinium odd isotopes nuclear cross sections data on the multiplication factor of some LWR fuel assemblies. The results have shown the importance of gadolinium odd isotopes in the criticality evaluation, and they confirmed the need of a re-evaluation of the neutron capture cross sections by means of new experimental measurements to be carried out at the n_TOF facility at CERN

    A geographically distributed bio-hybrid neural network with memristive plasticity

    Full text link
    Throughout evolution the brain has mastered the art of processing real-world inputs through networks of interlinked spiking neurons. Synapses have emerged as key elements that, owing to their plasticity, are merging neuron-to-neuron signalling with memory storage and computation. Electronics has made important steps in emulating neurons through neuromorphic circuits and synapses with nanoscale memristors, yet novel applications that interlink them in heterogeneous bio-inspired and bio-hybrid architectures are just beginning to materialise. The use of memristive technologies in brain-inspired architectures for computing or for sensing spiking activity of biological neurons8 are only recent examples, however interlinking brain and electronic neurons through plasticity-driven synaptic elements has remained so far in the realm of the imagination. Here, we demonstrate a bio-hybrid neural network (bNN) where memristors work as "synaptors" between rat neural circuits and VLSI neurons. The two fundamental synaptors, from artificial-to-biological (ABsyn) and from biological-to- artificial (BAsyn), are interconnected over the Internet. The bNN extends across Europe, collapsing spatial boundaries existing in natural brain networks and laying the foundations of a new geographically distributed and evolving architecture: the Internet of Neuro-electronics (IoN).Comment: 16 pages, 10 figure

    Production of radioisotopes within a plasma focus device

    Get PDF
    In recent years, research conducted in the US and in Italy has demonstrated production of radioisotopes in plasma focus devices, and particularly, on what could be termed "endogenous" production, to wit, production within the plasma it self, as opposed to irradiation of tar gets. This technique relies on the formation of localized small plasma zones characterized by very high densities and fairly high temperatures. The conditions prevailing in these zones lead to high nuclear reaction rates, as pointed out in previous work by several authors. Further investigation of the cross sections involved has proven necessary to model the phenomena involved. In this paper, the present status of research in this field is re viewed, both with regards to cross section models and to experimental production of radio isotopes. Possible out comes and further development are discussed

    Comunidad de paseriformes nidificantes de la Península Valdés (Patagonia, Argentina)

    Get PDF
    The Valdes Peninsula is a high-natural value area, located on the east coast of Argentine Patagonia. The aim of the reported research was to analyze the community of breeding passerine birds of the inland areas, with the purpose to identify the species that characterize each community, determining the main environmental typologies frequented, in order to study the relationships between bird richness and abundance, and environmental structure. During the breeding season 2011, 107 point counts were performed. 869 birds belonging to 23 passerine species were contacted and analyzed through a cluster analysis using the Indicator Value method. Results revealed the existence of two different communities: one that essentially refers to the grassy steppe where the characteristic species are Shortbilled Pipit (Anthus furcatus) and Common Miner (Geositta cunicularia), and the other one, which occupies the shrub-steppe consisting of more characteristic species, starting from the Rufous-collared Sparrow (Zonotrichia capensis), the most widespread species. These results update previous results on the community of passerines living in the study area and provide some useful insights for management purposes.La Península de Valdes es un area de gran riqueza natural, localizada en la costa Este de la Pa- tagonia Argentina. El propósito de este trabajo fue analizar la comunidad de aves Passeriformes de las areas internas de la región, con el proposito de identificar las especies que caracterizan cada comuni- dad, determinando las principales tipologias ambientales frecuentadas, para poder estudiar las rela- ciones entre la riqueza y abundancia de aves y la estructura del ambiente. Se realizaron 107 puntos de conteo durante la temporada reproductiva de 2011, en donde se detectaron 869 aves pertenecientes a 23 especies de Passeriformes. Para los análisis se usó el método de agrupamiento por el método del Indicator Value. Los resultados evidencian la existencia de dos diferentes comunidades: una asociada exclusivamente a la estepa herbácea y caracterizada por las especies Cachirla uña corta (Anthus furca- tus) y Minero común (Geositta cunicularia); mientras que la otra, asociada a la estepa arbustiva, es car- acterizada por diferentes especies típicas, como el Chingolo (Zonotrichia capensis), que es la especie de mayor distribución. Estos resultados constituyen una actualización al conocimiento de la fauna de la Península de Valdés, los cuales pueden ser útiles para el manejo y conservación de la avifauna de la región.Fil: Pruscini, Fabio. Università Di Urbino; ItaliaFil: Morelli, Federico. Università Di Urbino; ItaliaFil: Sisti, Davide. Università Di Urbino; ItaliaFil: Perna, Paolo. Universita Degli Di Camerino. Scuola Di Scienze Ambientale; ItaliaFil: Catorci, Andrea. Universita Degli Di Camerino. Scuola Di Scienze Ambientale; ItaliaFil: Bertellotti, Nestor Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Rocchi, Marco Bruno Luigi. Università Di Urbino; ItaliaFil: Santolini, Ricardo. Università Di Urbino; Itali

    53 a neuro specific gene therapy approach to treat cognitive impairment in down syndrome by rna interference

    Get PDF
    Down syndrome (DS) is a genetic disorder caused by the presence of a third copy of chromosome 21. DS affects multiple organs, resulting in characteristic facial features, muscular hypotonia, heart defects, brain development impairment, and varying degrees of intellectual disability. Trisomic mouse models of DS reproduce the main cognitive disabilities of the human syndrome. In particular, DS mice show structural and functional synaptic impairment as well as learning and memory deficits, largely determined by altered GABAergic transmission through chloride-permeable GABAa receptors (GABAaR). In particular, we have recently found that intracellular chloride accumulation shifts GABAAR-mediated signaling from inhibitory to excitatory in the adult brain of the Ts65Dn mouse model of DS. Accordingly, intracellular chloride accumulation was paralleled by increased expression of the chloride importer NKCC1 (Na-K-Cl cotransporter) in the brains of both trisomic mice and DS patients.Our findings on NKCC1 as a pivotal molecular target for the rescue of cognitive deficits in DS opens the possibility of a gene therapy approach to treat the disease. Here, to normalize NKCC1 expression and rescue synaptic dysfunctions as well as cognitive deficits in Ts65Dn mice we have developed and characterized a knock-down approach to normalize NKCC1 activity. Reducing the expression of the chloride importer NKCC1 by RNA interference restored GABAAR-mediated inhibition and also rescued the structural dendritic deficits found in trisomic neurons in vitro. Most importantly, focal administration of an AAV expressing a silencing RNA under the transcriptional control of a neuron-specific promoter in the hippocampus of Ts65Dn animals mediated NKCC1 knockdown in vivo and rescued behavioral performance on different learning and memory tests at levels undistinguishable from those of WT mice.Our findings demonstrate that NKCC1 overexpression drives excitatory GABAAR signaling in trisomic cells, leading to structural neuronal abnormalities and behavioral impairments in DS mice. Moreover, our study identifies a new gene therapy target for treatments aimed at rescuing cognitive disabilities in individuals with DS

    Are there sex differences in physiological parameters and reaction time responses to overload in firefighters?

    Get PDF
    Male and female firefighters work side-by-side in the same in strenuous and risky conditions. Anthropometrics, physiological, and reaction time (mean of reaction time -MRT-, and errors made -E) parameters of 12 Female and 13 Male firefighters were compared. Effect of overload (step test with and without equipment) on the MRT and E were analyzed on 3 trials (T1 = 1-1s, T2 = 0.5-1s, T3 = 0.5-0.5s), compared with a pre-test condition (basal). T-test between males and females was applied to assess differences (p<0.05) in all parameters. ANOVA with repeated measures and Bonferroni on 3 conditions of step test between males and females was applied in reaction time variables. Between MRT and E, in T1, T2 and T3 trials and the 3 test conditions, ANCOVA models with interactions were used. Differences (p<0.05) in anthropometric, physiological and reaction time data emerged across groups, and on the 3rd trials (T3 vs T1 and T2) in reaction time parameters of each group. ANCOVA showed differences (p<0.001) in E among trials. Post hoc showed significant differences in T1vsT3 and T1vsT2. MRT x trial interaction was extremely significant (P<0.001). Implementing fitness and reaction time exercise programs is important to decrease the injury risk and increase work capacity in firefighters with reference to female workers
    • …
    corecore