112 research outputs found

    Covariogram of non-convex sets

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    The covariogram of a compact set A contained in R^n is the function that to each x in R^n associates the volume of A intersected with (A+x). Recently it has been proved that the covariogram determines any planar convex body, in the class of all convex bodies. We extend the class of sets in which a planar convex body is determined by its covariogram. Moreover, we prove that there is no pair of non-congruent planar polyominoes consisting of less than 9 points that have equal discrete covariogram.Comment: 15 pages, 7 figures, accepted for publication on Mathematik

    Role of surface states in the Casimir force between semiconducting films

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    We present results of first principle calculations of the Casimir force between Si films of nanometric size, which show that it depends significantly upon the configuration of the surface atoms, and give evidence of the importance of surface states.Comment: to be published on J.Phys.

    An Algorithm for Reconstructing a Convex Polygon from its Covariogram

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    The covariogram of a compact convex set KRnK \subset \mathbb R^n is the function that at each point xRnx \in \mathbb R^n associates the volume of K(K+x)K \cap (K + x). The covariogram determines, among all convex bodies, any planar convex polygon. In this paper we present an algorithm for reconstructing an arbitrary convex polygon from its covariogram

    EOLO: Sistema per la regolazione controllata di gas ad uso medico per terapia e diagnosi

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    not availableIl progetto riguarda principalmente l\u27ossigeno terapia e la somministrazione di ossido nitrico per terapia e diagnostica La somministrazione controllata di gas ad uso terapeutico ? oggi una pratica clinica consolidata in special modo nella ossigeno terapia per patologie quali le broncopneumopatie croniche ostruttive (BPCO). Nuove terapie con altri gas quali l\u27ossido nitrico NO rappresentano metodiche in corso di validazione clinica ma gi? accettate da organismi di controllo quali FDA, soprattutto nei casi di ipertensione polmonare primitiva. Ci si riferisce quindi a sistemi di somministrazione di gas, come quelli rammentati, mettendo a punto metodiche originarie di "feedback" su parametri fisiologici, misurati durante la terapia in modo incruento, per gestire i relativi dispositivi di erogazione del gas stesso e al monitoraggio delle variabili biologiche rilevanti da parte di centri opportuni. Le malattie respiratorie, dopo le malattie cardiocircolatorie ed i tumori, sono tra le maggiori cause di morte nel mondo. Il loro trend ? crescente, essendo esse causate, fra l\u27altro, da fattori come il fumo e l\u27inquinamento, che sono a loro volta in crescita. Da qui la necessit? di realizzare sistemi semplici ed efficaci per il controllo della strumentazione di ossigenoterapia in una vasta popolazione, anche per gli usi domiciliari. Non ultimo diventa importante con questi numeri, pensare ad una razionalizzazione automatica dei consumi di ossigeno. Per quel che riguarda l\u27ipertensione polmonare, altra patologia verso cui EOLO ? rivolto, un potenziale rimedio ? costituito dalla somministrazione in dosi terapeutiche di Ossido Nitrico in sostituzione ad esempio delle prostacicline con il vantaggio di non ricorrere ad applicazioni invasive cruente e di evitare effetti collaterali sistemici. L\u27uso di questo gas medicale ? per? limitata in quanto il mercato non propone dispositivi per la somministrazione di ossido nitrico ottimizzati alle sue indicazioni d\u27uso. Le indicazione d\u27uso prevedono, infatti, la somministrazione di ossido nitrico a bassi dosaggi(5-40 ppm) e la limitazione del tempo di contatto tra l\u27ossido nitrico e i gas inalatori che il paziente deve respirare. Tale metodologia di somministrazione ? requisito essenziale per il suo impiego, in quanto questo gas si combina molto velocemente con l\u27ossigeno formando Biossido d\u27Azoto (NO2), un gas altamente nocivo. Il biossido di azoto reagendo a sua volta con l\u27acqua forma acido nitrico (HNO3), che ? un acido particolarmente reattivo quindi pericoloso

    Spatial segregation of Darwinula stevensoni (Crustacea: Ostracoda) genotypes in lentic and lotic habitats of Northern Italy

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    The clonal structure of apomictic populations of Darwinula stevensoni from Northern Italy lacustrine and riverine habitats has been analysed by allozyme electrophoresis. Thirty two sites were sampled and a total of 748 individuals were analysed. Only one polymorphic locus, Gpi, turned out to have enough variation to be informative. Two thirds of all individuals were homozygous for the most frequent allele but the frequency of this genotype was significantly lower in rivers (16%) than in lakes (92%). As a consequence homozygous clonal females are dominant in lacustrine habitats while heterozygous clonal females are dominant in riverine ones. Differences in genetic structure between habitats were observed even at distances of a few meters. Allele and genotype frequencies are significantly different between Lake Montorfano and its outflow (River Seveso) and between Mantova lakes and their two tributaries, the River Mincio and Corniano Channel. The former is also the outflow of Lake Garda. By laboratory experiments, we previously reported difference between genotypes: homozygous females from Mantova lakes show significantly lower starvation tolerance than heterozygous females from River Mincio. We discuss the hypothesis that habitat segregation is related to this difference. Riverine females should be better adapted to low productivity ecosystems than lacustrine ones

    Chemical composition and biological activities of the leaves of Cynara scolymus L. (artichoke) cultivated in Brazil

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    The present paper describes the chemical composition and biological activities of artichoke cultivated in Brazil. Our studies demonstrated that glycosyl flavonoids (cynaroside and scolymoside), are the major constituents, along with cynaropicrin, a sesquiterpene lactone, and the triterpene lupeol. Cynarin, which is the main compound described for artichoke, was detected in very low concentration. Hexanic fraction exhibited considerable cytotoxicity and diuretic activities

    HABITAT: An IoT Solution for Independent Elderly

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    In this work, a flexible and extensive digital platform for Smart Homes is presented, exploiting the most advanced technologies of the Internet of Things, such as Radio Frequency Identification, wearable electronics, Wireless Sensor Networks, and Artificial Intelligence. Thus, the main novelty of the paper is the system-level description of the platform flexibility allowing the interoperability of different smart devices. This research was developed within the framework of the operative project HABITAT (Home Assistance Based on the Internet of Things for the Autonomy of Everybody), aiming at developing smart devices to support elderly people both in their own houses and in retirement homes, and embedding them in everyday life objects, thus reducing the expenses for healthcare due to the lower need for personal assistance, and providing a better life quality to the elderly users

    Asymmetric information and financial markets : from financial intermediation to credit rationing

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    Digitised version produced by the EUI Library and made available online in 2020
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