52 research outputs found

    Mapping road network communities for guiding disease surveillance and control strategies

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    Human mobility is increasing in its volume, speed and reach, leading to the movement and introduction of pathogens through infected travelers. An understanding of how areas are connected, the strength of these connections and how this translates into disease spread is valuable for planning surveillance and designing control and elimination strategies. While analyses have been undertaken to identify and map connectivity in global air, shipping and migration networks, such analyses have yet to be undertaken on the road networks that carry the vast majority of travellers in low and middle income settings. Here we present methods for identifying road connectivity communities, as well as mapping bridge areas between communities and key linkage routes. We apply these to Africa, and show how many highly-connected communities straddle national borders and when integrating malaria prevalence and population data as an example, the communities change, highlighting regions most strongly connected to areas of high burden. The approaches and results presented provide a flexible tool for supporting the design of disease surveillance and control strategies through mapping areas of high connectivity that form coherent units of intervention and key link routes between communities for targeting surveillance.Comment: 11 pages, 5 figures, research pape

    Design and Validation of Network-on-Chip Architectures for the Next Generation of Multi-synchronous, Reliable, and Reconfigurable Embedded Systems

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    NETWORK-ON-CHIP (NoC) design is today at a crossroad. On one hand, the design principles to efficiently implement interconnection networks in the resource-constrained on-chip setting have stabilized. On the other hand, the requirements on embedded system design are far from stabilizing. Embedded systems are composed by assembling together heterogeneous components featuring differentiated operating speeds and ad-hoc counter measures must be adopted to bridge frequency domains. Moreover, an unmistakable trend toward enhanced reconfigurability is clearly underway due to the increasing complexity of applications. At the same time, the technology effect is manyfold since it provides unprecedented levels of system integration but it also brings new severe constraints to the forefront: power budget restrictions, overheating concerns, circuit delay and power variability, permanent fault, increased probability of transient faults. Supporting different degrees of reconfigurability and flexibility in the parallel hardware platform cannot be however achieved with the incremental evolution of current design techniques, but requires a disruptive approach and a major increase in complexity. In addition, new reliability challenges cannot be solved by using traditional fault tolerance techniques alone but the reliability approach must be also part of the overall reconfiguration methodology. In this thesis we take on the challenge of engineering a NoC architectures for the next generation systems and we provide design methods able to overcome the conventional way of implementing multi-synchronous, reliable and reconfigurable NoC. Our analysis is not only limited to research novel approaches to the specific challenges of the NoC architecture but we also co-design the solutions in a single integrated framework. Interdependencies between different NoC features are detected ahead of time and we finally avoid the engineering of highly optimized solutions to specific problems that however coexist inefficiently together in the final NoC architecture. To conclude, a silicon implementation by means of a testchip tape-out and a prototype on a FPGA board validate the feasibility and effectivenes

    Plot-based urbanism and urban morphometrics : measuring the evolution of blocks, street fronts and plots in cities

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    Generative urban design has been always conceived as a creation-centered process, i.e. a process mainly concerned with the creation phase of a spatial transformation. We argue that, though the way we create a space is important, how that space evolves in time is ways more important when it comes to providing livable places gifted by identity and sense of attachment. We are presenting in this paper this idea and its major consequences for urban design under the title of “Plot-Based Urbanism”. We will argue that however, in order for a place to be adaptable in time, the right structure must be provided “by design” from the outset. We conceive urban design as the activity aimed at designing that structure. The force that shapes (has always shaped) the adaptability in time of livable urban places is the restless activity of ordinary people doing their own ordinary business, a kind of participation to the common good, which has hardly been acknowledged as such, that we term “informal participation”. Investigating what spatial components belong to the spatial structure and how they relate to each other is of crucial importance for urban design and that is the scope of our research. In this paper a methodology to represent and measure form-related properties of streets, blocks, plots and buildings in cities is presented. Several dozens of urban blocks of different historic formation in Milan (IT) and Glasgow (UK) are surveyed and analyzed. Effort is posed to identify those spatial properties that are shared by clusters of cases in history and therefore constitute the set of spatial relationships that determine the morphological identity of places. To do so, we investigate the analogy that links the evolution of urban form as a cultural construct to that of living organisms, outlining a conceptual framework of reference for the further investigation of “the DNA of places”. In this sense, we identify in the year 1950 the nominal watershed that marks the first “speciation” in urban history and we find that factors of location/centrality, scale and street permeability are the main drivers of that transition towards the entirely new urban forms of contemporary cities

    Spatio-temporal analysis of micro economic activities in Rome reveals patterns of mixed-use urban evolution

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    Understanding urban growth is one with understanding how society evolves to satisfy the needs of its individuals in sharing a common space and adapting to the territory. We propose here a quantitative analysis of the historical development of a large urban area by investigating the spatial distribution and the age of commercial activities in the whole city of Rome. We find that the age of activities of various categories presents a very interesting double exponential trend, with a transition possibly related to the longterm economical effects determined by the oil crisis of the Seventies. The diversification of commercial categories, studied through various measures of entropy, shows, among other interesting features, a saturating behaviour with the density of activities. Moreover, different couples of commercial categories exhibit over the years a tendency to attract in space. Our results demonstrate that the spatio-temporal distribution of commercial activities can provide important insights on the urbanisation processes at work, revealing specific and not trivial socio-economical dynamics, as the presence of crisis periods and expansion trends, and contributing to the characterisation of the maturity of urban areas

    MALAT1-dependent hsa_circ_0076611 regulates translation rate in triple-negative breast cancer

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    Vascular Endothelial Growth Factor A (VEGFA) is the most commonly expressed angiogenic growth factor in solid tumors and is generated as multiple isoforms through alternative mRNA splicing. Here, we show that lncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) and ID4 (inhibitor of DNA-binding 4) protein, previously referred to as regulators of linear isoforms of VEGFA, induce back-splicing of VEGFA exon 7, producing circular RNA circ_0076611. Circ_0076611 is detectable in triple-negative breast cancer (TNBC) cells and tissues, in exosomes released from TNBC cells and in the serum of breast cancer patients. Circ_0076611 interacts with a variety of proliferation-related transcripts, included MYC and VEGFA mRNAs, and increases cell proliferation and migration of TNBC cells. Mechanistically, circ_0076611 favors the expression of its target mRNAs by facilitating their interaction with components of the translation initiation machinery. These results add further complexity to the multiple VEGFA isoforms expressed in cancer cells and highlight the relevance of post-transcriptional regulation of VEGFA expression in TNBC cells

    A Probable Fatal Case of Oleander (Nerium oleander) Poisoning on a Cattle Farm: A New Method of Detection and Quantification of the Oleandrin Toxin in Rumen

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    Oleander (Nerium oleander) is an ornamental plant common in tropical and sub-tropical regions that is becoming increasingly widespread, even in temperate regions. Oleander poisoning may occur in animals and humans. The main active components contained in the plant are cardiac glycosides belonging to the class of cardenolides that are toxic to many species, from human to insects. This work describes a case of oleander poisoning that occurred on a small cattle farm and resulted in the fatality of all six resident animals. Furthermore, the investigation of the poisonous agent is described, with particular focus on the characterization of the oleandrin toxin that was recovered from the forage and rumen contents. The innovation of this study is the first description of the detection and quantification of the oleandrin toxin by liquid chromatography-high resolution mass spectrometry (LC-HRMS) in rumen

    L'etichettatura degli alimenti geneticamente modificati negli USA. Tutela del consumatore e innovazione tecnologica in un ordinamento multilivello.

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    La tesi analizza in parallelo l’evoluzione delle tecnologie di manipolazione del DNA e l’evoluzione della normativa statunitense in materia di etichettatura degli alimenti contenenti OGM. Il primo capitolo ripercorre la storia dell’agricoltura industriale fino ai primi esperimenti di ingegneria genetica e ricostruisce la disciplina federale in materia di cibi bioingegnerizzati a partire dal Coordinated Framework for Regulation of Biotechnology; successivamente, illustra le più recenti tecnologie di genome editing ed il loro rapporto con la regolamentazione statunitense. Il secondo capitolo mostra l’evoluzione dell’opinione pubblica americana rispetto al tema degli OGM e ripercorre le iniziative legislative locali e statali volte a dare risposta al crescente malcontento dei consumatori; infine, analizza l’Act 120, una legge promulgata nello Stato Vermont che impone la segnalazione in etichetta di alcuni alimenti prodotti attraverso l’ingegneria genetica. Il terzo capitolo esamina le questioni di legittimità costituzionale legate alle leggi statali in materia di etichettatura degli alimenti bioingegnerizzati, con particolare riferimento alla federal preemption e alle potenziali violazioni del primo emendamento e della dormant commerce clause. Il quarto capitolo analizza la Public Law 114-216, varata dal Congresso degli Stati Uniti per disciplinare la materia e al contempo per rendere nulle le normative statali mediante l’istituto della federal preemption: la soluzione normativa adottata dal legislatore federale impone uno standard nazionale di disclosure molto circoscritto nella portata e permissivo nelle modalità di segnalazione. Le conclusioni finali suggeriscono che la legge federale, pur fondata su criteri scientificamente solidi, sia facilmente aggirabile con gli strumenti offerti dalle tecniche di genome editing e che essa non risponda in maniera adeguata alla crescente volontà espressa dai consumatori americani di essere informati sull'utilizzo della bioingegneria nel processo produttivo degli alimenti in commercio

    Optimizing built-in pseudo-random self-testing for network-on-chip switches

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    Most BIST architectures use pseudo-random test pattern generators. However, whenever this technique has been applied to on-chip interconnection networks, overly large testing latencies have been reported. On the other hand, alternative approaches either suffer from large area penalties (like scan-based testing or the use of deterministic test patterns) or poor coverage of faults in the control path (functional testing). This paper presents the optimization of a built-in self-testing framework based on pseudo-random test patterns to the microarchitecture of network-on-chip switches. As a result, fault coverage and testing latency approach those achievable with deterministic test patterns while materializing relevant area savings and enhanced flexibility
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