Concevoir à grande échelle

L’échelle d’un édifice peut être quantifiée à la fois par sa longueur mais aussi par le rapport à son contexte. L’entrepôt Macdonald est à l’échelle d’une tour horizontale de 617 mètres de long : c’est un projet à grande échelle, à l’intermédiaire entre un bâtiment et un quartier. Pour comprendre son nouvel impact dans un site en mutation, il faut étudier les typologies de projets à grande échelle : les projets architecturaux utopiques et construits, mais également les formes urbaines nouvelles qui répondent au développement des villes. Cette analyse théorique et comparative met en avant trois paramètres qui définissent la grande échelle aujourd’hui : la taille, la multifonctionnalité et la complexité. Comment la reconversion de l’entrepôt annonce-t-elle une nouvelle échelle de réflexion pour la ville

Study of multicomponent chromatograms using a chemometric approach: characterization of the organic fraction of atmospheric aerosol

In this Ph.D. project it has been developed a study of multicomponent chromatograms of complex mixtures, using a chemometric approach. The activity has been concentrated in the study of analytical-separative methods (in particular Gas Cromatography-Mass Spectrometry, GC-MS) for complex samples of environmental interest, especially for PM (particulate matter) samples. A fundamental part of this Ph.D. project has been dedicated to the development of mathematical and statistical algorithms for the data treatment of the GC-MS signal obtained from the analysis, in order to extract relevant information from the complex chromatogram, such as important indexes involved in the environmental studies. In particular, the project involved the identification and the characterization of homologous series of organic compounds (n-alkanes and carboxylic acids) that could be usually found in environmental samples, because they contain fundamental information to distinguish, for example, different types of emission sources, anthropic or biogenic. It has been developed a chemometric approach, which uses the AutoCoVariance Function (ACVF) computed on the digitized chromatogram, in order to quantificate the number of terms of the homologous series (nmax) and their distribution, with particular attention to the relative abundance and, consequently, the prevalance of the odd to even terms of the series (CPI). This is one of the most important parameters (environmental biomarkers) to perform a study of source apportionment. The method has been validated using simulated chromatograms and its applicability has been tested, with successful results, on real samples of known origin (e.g. gasoil or plant samples) and, finally, to particulate matter samples, obtained thanks to a collaboration with the research group of Environmental Sciences Department of the University of Milano Bicocca

Immaginazione computazionale e digital art history

This essay explores the parallel rising of computer vision technology and digital art history, examining some of the current possibilities and limits of computational techniques applied to the cultural and historical studies of images. A fracture emerges: computer scientists seems to lack in the critical approach typical of the humanities, a shortfall which sometimes condemns their attempts to remain technological curiosities. For their part, humanists lack in technical knowledge that is needed to directly investigate big archives of images, with the result that art historians often must limit their attempts in the computer-aided inquires on texts or metadata databases, a task that does not imply the study of the images themselves. A future dialogue between the two areas is claimed as a necessity in order to foster this new branch of knowledge

Bernadette Lizet, Le cheval dans la vie quotidienne. Techniques et représentations du cheval de travail dans l’Europe industrielle

Comment les relations entre êtres humains, animaux et environnement naturel ont-elles évolué au fil des siècles ? Et quelles sont les conséquences générées par un siècle et demi d’industrialisation ? À l’aune des crises sanitaires, sociales et économiques, la réédition de l’ouvrage Le cheval dans la vie quotidienne de Bernadette Lizet permet une lecture précise des changements qui ont produit la société contemporaine. Publié pour la première fois en 1982 aux éditions Berger Levrault, avec une..

Comparing the efficiency of normal form systems to represent Boolean functions

In this paper we compare various normal form representations of Boolean functions. We extend the study of [4], pertaining to the comparison of the asymptotic efficiency of representations that are produced by normal form systems (NFSs) that are factorizations of the clone Ω of all Boolean functions. We identify some properties, such as associativity, linearity, quasi-linearity and symmetry , that allow the efficiency of the corresponding NFSs to be compared in terms of the non-trivial connectives used. We illustrate these results by comparing well-known NFSs such as the DNF, CNF, Zhegalkin (Reed-Muller) polynomial (PNF) and Median (MNF) representations, thereby confirming the results of [4]. In particular, we show that the MNF is of equivalent complexity to, e.g., the Sheffer Normal Form (SNF), UNF and WNF (associated with 1 and 0-separating functions respectively) and thus that the latter are polynomially as efficient as any other NFS, and are strictly more efficient than the DNF, CNF, and Zhegalkin polynomial representations

Sur l'efficacité des systèmes de formes normales de fonctions Booléennes

National audienceIn this paper we compare various normal form representations of Boolean functions. We extend the study of [3] pertaining to the comparison of the asymptotic efficiency of representations produced by normal form systems (NFSs). We identify some properties, such as as-sociativity, linearity, quasi-linearity and symmetry, that allow the efficiency of the corresponding NFSs to be compared. We illustrate these results by comparing well-known NFSs such as the DNF, CNF, polynomial (PNF) representations, as well as the Median Normal Form (MNF) and Sheffer Normal Form (SNF). We obtain in particular that NFSs generated by a single connective are polynomially as efficient as those generated by several connectives. As for the MNF, it is as efficient as any other NFS.Dans cet article, nous comparons différentes représen-tations des fonctions Booléennes à l'aide de systèmes de formes normales. Nous étendons les travaux de [3] sur l'étude asymptotique de l'efficacité des représentations produites par des systèmes de formes normales (Normal Form Systems–NFSs). Nous identifions certaines proprié-tés, comme l'associativité, la linéarité, la quasi-linéarité et la symétrie, qui nous permettent de comparer l'effica-cité des NFSs correspondantes. Nous illustrons ces résul-tats en comparant des NFSs usuelles telles que la DNF, CNF, les représentations polynomiales, ainsi que la forme normale médiane (MNF) et celle dite de Sheffer (SNF). Nous obtenons en particulier que les NFSs générés par un seul connecteur sont polynomialement aussi efficace que ceux générés par plusieurs. La MNF, quand à elle, est aussi efficace que n'importe quel autre système

Epidemiological characteristics and outcomes of COVID-19 cases: mortality inequalities by socio-economic status, Barcelona, Spain, 24 February to 4 May 2020

Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Epidemiologia; Situació socioeconòmicaCoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Epidemiología; Estatus socioeconómicoCoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Epidemiology; Socio-economic statusBackground: Population-based studies characterising outcomes of COVID-19 in European settings are limited, and effects of socio-economic status (SES) on outcomes have not been widely investigated. Aim: We describe the epidemiological characteristics of COVID-19 cases, highlighting incidence and mortality rate differences across SES during the first wave in Barcelona, Catalonia, Spain. Methods: This population-based study reports individual-level data of laboratory-confirmed COVID-19 cases diagnosed from 24 February to 4 May 2020, notified to the Public Health Agency of Barcelona and followed until 15 June 2020. We analysed end-of-study vital status and the effects of chronic conditions on mortality using logistic regression. Geocoded addresses were linked to basic health area SES data, estimated using the composed socio-economic index. We estimated age-standardised incidence, hospitalisation, and mortality rates by SES. Results: Of 15,554 COVID-19-confirmed cases, the majority were women (n =9,028; 58%), median age was 63 years (interquartile range: 46–83), 8,046 (54%) required hospitalisation, and 2,287 (15%) cases died. Prevalence of chronic conditions varied across SES, and multiple chronic conditions increased risk of death (≥3, adjusted odds ratio: 2.3). Age-standardised rates (incidence, hospitalisation, mortality) were highest in the most deprived SES quartile (incidence: 1,011 (95% confidence interval (CI): 975–1,047); hospitalisation: 619 (95% CI: 591–648); mortality: 150 (95% CI: 136–165)) and lowest in the most affluent (incidence: 784 (95% CI: 759–809); hospitalisation: 400 (95% CI: 382–418); mortality: 121 (95% CI: 112–131)). Conclusions: COVID-19 outcomes varied markedly across SES, underscoring the need to implement effective preventive strategies for vulnerable populations

Median based calculus for lattice polynomials and monotone Boolean functions

International audienceIn this document, we consider a median-based calculus for efficiently representing polynomial functions over distributive lattices. We extend an equational specification of median forms from the domain of Boolean functions to the domain of lattice polynomials. We show that it is sound and complete, and we illustrate its usefulness when simplifying median formulas algebraically. Furthermore, we propose a definition of median normal forms (MNF), that are thought of as minimal median formulas with respect to a structural ordering of expressions. We also investigate related complexity issues and show that the problem of deciding whether a formula is in MNF is in Σ^P_2. Moreover, we explore polynomial approximations of solutions to this problem through a sound term rewriting system extracted from the proposed equational specification

Identification of Prototheca from the Cerebrospinal Fluid of a Cat with Neurological Signs

Prototheca infections are rare in cats, and they are usually associated with cutaneous or subcutaneous infections by P. wickerhamii, with no evidence of neurological signs or systemic disease. In this study, we report the identification of prototheca in the cerebrospinal fluid (CSF) of a cat with neurological symptoms. Fourteen CSF samples were gathered from cats presented with neurological disease between 2012 and 2014. The inclusion criteria for the samples were an increase in CSF protein and cell number (pleocytosis), suggestive of an infectious inflammatory status of the central nervous system (CNS). Nine samples fulfilled the inclusion criteria (inflammatory samples), while five samples, used as control, did not (non-inflammatory samples). All the samples were screened molecularly for different pathogens associated with CNS disease in cats, including prototheca. Out of 14 CSF samples, only one inflammatory sample tested positive for prototheca. Upon sequence and phylogenetic analysis of the amplicon, the strain was characterized as P. bovis. This report is the first documented evidence of prototheca in the cerebrospinal fluid of a cat with neurological signs. Prototheca should be considered in the diagnostics procedures on the CNS of cats presented with infectious diseases

On the complexity of minimizing median normal forms of monotone Boolean functions and lattice polynomials

International audienceIn this document, we consider a median-based calculus to represent monotone Boolean functions efficiently. We study an equa-tional specification of median forms and extend it from the domain of monotone Boolean functions to the domain of polynomial functions over distributive lattices. This specification is sound and complete. We illustrate its usefulness when simplifying median formulas algebraically. Furthermore, we propose a definition of median normal forms (MNF), that are thought of as minimal median formulas with respect to a structural ordering of expressions. We investigate related complexity issues and show that the problem of deciding whether a formula is in MNF, that is the problem of minimizing the median form of a monotone Boolean function, is in Σ P 2. Moreover, we show that it still holds for arbitrary Boolean functions, not necessarily monotone