1,597 research outputs found
La Fisica nel parco giochi fa bene anche al curriculum
Viene descritto un percorso didattico di fisica attraverso le attrazioni del parco di divertimenti di Mirabilandia (Ravenna). Viene in particolare illustrata un’esperienza di integrazione del percorso nel curriculum scolastico di fisica, condotta in una classe III di liceo scientifico, che ha avuto risultati positivi sull’apprendimento
A new clinical tool for assessing numerical abilities in neurological diseases: numerical activities of daily living
The aim of this study was to build an instrument, the numerical activities of daily living (NADL), designed to identify the specific impairments in numerical functions that may cause problems in everyday life. These impairments go beyond what can be inferred from the available scales evaluating activities of daily living in general, and are not adequately captured by measures of the general deterioration of cognitive functions as assessed by standard clinical instruments like the MMSE and MoCA. We assessed a control group (n = 148) and a patient group affected by a wide variety of neurological conditions (n = 175), with NADL along with IADL, MMSE, and MoCA. The NADL battery was found to have satisfactory construct validity and reliability, across a wide age range. This enabled us to calculate appropriate criteria for impairment that took into account age and education. It was found that neurological patients tended to overestimate their abilities as compared to the judgment made by their caregivers, assessed with objective tests of numerical abilities
Wind speed dependent size-resolved parameterization for the organic mass fraction of sea spray aerosol
For oceans to be a significant source of primary organic aerosol (POA), sea spray aerosol (SSA) must be highly enriched with organics relative to the bulk seawater. We propose that organic enrichment at the air-sea interface, chemical composition of seawater, and the aerosol size are three main parameters controlling the organic mass fraction of sea spray aerosol (OM<sub>SSA</sub>). To test this hypothesis, we developed a new marine POA emission function based on a conceptual relationship between the organic enrichment at the air-sea interface and surface wind speed. The resulting parameterization is explored using aerosol chemical composition and surface wind speed from Atlantic and Pacific coastal stations, and satellite-derived ocean concentrations of chlorophyll-<i>a</i>, dissolved organic carbon, and particulate organic carbon. Of all the parameters examined, a multi-variable logistic regression revealed that the combination of 10 m wind speed and surface chlorophyll-<i>a</i> concentration ([Chl-<i>a</i>]) are the most consistent predictors of OM<sub>SSA</sub>. This relationship, combined with the published aerosol size dependence of OM<sub>SSA</sub>, resulted in a new parameterization for the organic mass fraction of SSA. Global emissions of marine POA are investigated here by applying this newly-developed relationship to existing sea spray emission functions, satellite-derived [Chl-<i>a</i>], and modeled 10 m winds. Analysis of model simulations shows that global annual submicron marine organic emission associated with sea spray is estimated to be from 2.8 to 5.6 Tg C yr<sup>−1</sup>. This study provides additional evidence that marine primary organic aerosols are a globally significant source of organics in the atmosphere
The reception of Italian neo-Latin poetry in English manuscript sources, c. 1550-1720: literature, morality, and anti-Popery
This essay presents a preliminary overview of the presence of, and engagement with, Italian neo-Latin poetry in a large corpus of English manuscript sources dating from between c.1550 and c.1720 and currently conserved in English libraries and archives. Italian neo-Latin verse circulated widely in these manuscripts, where it was, however, subject to a process of selective cultural appropriation. The moralising intent of several manuscript miscellanies, and of commonplace books in particular, especially encouraged the quotation of brief poetic extracts, selected because of their edifying potential. Moreover, the availability of printed anthologies, school texts, and editions enabled different levels of familiarity with individual Italian poets: Mantuan and Palingenius, for example, are well-represented in early modern manuscripts as they were in the contemporary English school curriculum. Overall, the manuscript collectors’ selective redeployment of the Italian neo-Latin tradition particularly emphasises its anti-Papal potential, in line with the collectors’ generally Protestant views
Lucan and Virgil: from Dante to Petrarch (and Boccaccio)
Questioning recent accounts of Dante's Lucan, this article argues that Dante does not view Lucan as an "anti-Virgil", but rather regards and redeploys the "Bellum Civile" and the "Aeneid" as fundamentally consonant with each other. In the "Divine Comedy", Dante interweaves Lucan's and Virgil's works as expressions of the same moral, poetic, and historical universe: this literary strategy finds significant parallels in medieval Latin commentaries on Lucan's poem. In the "Monarchia" and "Epistles", Dante combines Lucan's and Virgil's texts to underpin his pro-monarchist agenda, effacing the contrast between Roman Republican and Imperial ideals. Far from regarding Lucan as a "nihilistic" author, Dante references him as a moral-philosophical "auctoritas"; in the "Convivio", he applies to the "Bellum Civile" the same allegorizing reading he adopts for the "Aeneid". The article demonstrates the difference between Dante's and late-fourteenth-century views of Lucan in relation to Virgil. Unlike Dante, the early humanists Petrarch and Boccaccio emphasize Lucan's controversial biography and the idea of his poetic rivalry with Virgil. However, the concept of Lucan's anti-Virgilianism, which underlies twentieth-century interpretations of the "Bellum Civile", is much more nuanced in fourteenth-century receptions of the poem, where it emerges only gradually and in a very limited, mostly biographical, sense
A Philosophical Quarrel among "auctoritates": Mussato's "De Lite inter Naturam et Fortunam" and its Classical and Medieval Sources
Surface tensions of multi-component mixed inorganic/organic aqueous systems of atmospheric significance: measurements, model predictions and importance for cloud activation predictions
International audienceIn order to predict the physical properties of aerosol particles, it is necessary to adequately capture the behaviour of the ubiquitous complex organic components. One of the key properties which may affect this behaviour is the contribution of the organic components to the surface tension of aqueous particles in the moist atmosphere. Whilst the qualitative effect of organic compounds on solution surface tensions has been widely reported, our quantitative understanding on mixed organic and mixed inorganic/organic systems is limited. Furthermore, it is unclear whether models that exist in the literature can reproduce the surface tension variability for binary and higher order multi-component organic and mixed inorganic/organic systems of atmospheric significance. The current study aims to resolve both issues to some extent. Surface tensions of single and multiple solute aqueous solutions were measured and compared with predictions from a number of model treatments. On comparison with binary organic systems, two predictive models found in the literature provided a range of values resulting from sensitivity to calculations of pure component surface tensions. Results indicate that a fitted model can capture the variability of the measured data very well, producing the lowest average percentage deviation for all compounds studied. The performance of the other models varies with compound and choice of model parameters. The behaviour of ternary mixed inorganic/organic systems was unreliably captured by using a predictive scheme and this was dependent on the composition of the solutes present. For more atmospherically representative higher order systems, entirely predictive schemes performed poorly. It was found that use of the binary data in a relatively simple mixing rule, or modification of an existing thermodynamic model with parameters derived from binary data, was able to accurately capture the surface tension variation with concentration. Thus, it would appear that in order to model multi-component surface tensions involving compounds used in this study one requires the use of appropriate binary data. However, results indicate that the use of theoretical frameworks which contain parameters derived from binary data may predict unphysical behaviour when taken beyond the concentration ranges used to fit such parameters. The effect of deviations between predicted and measured surface tensions on predicted critical saturation ratios was quantified, by incorporating the surface tension models into an existing thermodynamic framework whilst firstly neglecting bulk to surface partitioning. Critical saturation ratios as a function of dry size for all of the multi-component systems were computed and it was found that deviations between predictions increased with decreasing particle dry size. As expected, use of the surface tension of pure water, rather than calculate the influence of the solutes explicitly, led to a consistently higher value of the critical saturation ratio indicating that neglect of the compositional effects will lead to significant differences in predicted activation behaviour even at large particle dry sizes. Following this two case studies were used to study the possible effect of bulk to surface partitioning on critical saturation ratios. By employing various assumptions it was possible to perform calculations not only for a binary system but also for a mixed organic system. In both cases this effect lead to a significant increase in the predicted critical supersaturation ratio compared to the above treatment. Further analysis of this effect will form the focus of future work
Structure-activity relationship in monosaccharide-based Toll-like receptor 4 (TLR4) antagonists
The structure-activity relationship was investigated in a series of synthetic TLR4 antagonists formed by a glucosamine core linked to two phosphate esters and two linear carbon chains. Molecular modeling showed that the compounds with 10, 12, and 14 carbons chains are associated with higher stabilization of the MD-2/TLR4 antagonist conformation than in the case of the C16 variant. Binding experiments with human MD-2 showed that the C12 and C14 variants have higher affinity than C10, while the C16 variant did not interact with the protein. The molecules, with the exception of the C16 variant, inhibited the LPS-stimulated TLR4 signal in human and murine cells, and the antagonist potency mirrored the MD-2 affinity calculated from in vitro binding experiments. Fourier-transform infrared, nuclear magnetic resonance, and small angle X-ray scattering measurements suggested that the aggregation state in aqueous solution depends on fatty acid chain lengths and that this property can influence TLR4 activity in this series of compounds
Circumstellar discs: What will be next?
This prospective chapter gives our view on the evolution of the study of
circumstellar discs within the next 20 years from both observational and
theoretical sides. We first present the expected improvements in our knowledge
of protoplanetary discs as for their masses, sizes, chemistry, the presence of
planets as well as the evolutionary processes shaping these discs. We then
explore the older debris disc stage and explain what will be learnt concerning
their birth, the intrinsic links between these discs and planets, the hot dust
and the gas detected around main sequence stars as well as discs around white
dwarfs.Comment: invited review; comments welcome (32 pages
Development of experimental and numerical methods for the analysis of active clearance control systems
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