34 research outputs found

    Catoptric Anamorphosis on Free-Form Reflective Surfaces

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    Lo studio si concentra sulla definizione di una metodologia geometrica per l’impiego dell’anamorfosi catottrica nell’architettura contemporanea. Viene illustrato il particolare fenomeno proiettivo, mostrandone proprietà tipologico-geometriche, rispondenti a meccanismi di riflessione della luce. Si evidenzia che le esperienze pregresse, nel corso dei secoli, impiegano la tecnica, relegando la realizzazione esclusivamente a dispositivi riflettenti realizzati da geometrie semplici, a piccola scala e quasi esclusivamente per specchi convessi. Volendo estendere l’impiego del fenomeno proiettivo e sperimentare le potenzialità espressive su superfici riflettenti di natura geo- metrica complessa free-form, i metodi geometrici tradizionali limitano la progettualità e il controllo preventivo degli esiti, facendo così venire meno l’effetto desiderato. Si propone, quindi, un processo metodologico generalizzabile di implementazione, definito mediante l’impiego di procedure algoritmico-parametriche, per la determinazione di immagini deformate, descrivendo possibili sviluppi successivi.The study focuses on the definition of a geometric methodology for the use of catoptric anamorphosis in contemporary architecture. The particular projective phenomenon is illustrated, showing typological-geometric properties, responding to mechanisms of light reflection. It is pointed out that previous experience, over the centuries, employed the technique, relegating its realisation exclusively to reflecting devices realised by simple geometries, on a small scale and almost exclusively for convex mirrors. Wanting to extend the use of the projective phenomenon and experiment with the expressive potential on reflective surfaces of a complex geometric free-form nature, traditional geometric methods limit the design and prior control of the results, thus causing the desired effect to fail. Therefore, a generalisable methodological process of implementation is proposed, defined through the use of algorithmic-parametric procedures, for the determination of deformed images, describing possible subsequent developments

    Virtual Network Function Embedding with Quantum Annealing

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    In recent years, the growing number of devices connected to the internet led network operators to continuously expand their own infrastructures. In order to simplify this scaling process, the research community is currently investigating the opportunity to move the complexity from a hardware to a software domain, through the introduction of a new paradigm, called Network Functions Virtualisation (NFV). It considers standard hardware platforms where many virtual instances are allocated to implement specific network services. However, despite the theoretical benefits, the mapping of the different virtual instances to the available physical resources represents a complex problem, difficult to be solved classically. The present work proposes a Quadratic Unconstrained Binary Optimisation (QUBO) formulation of this embedding process, exploring the implementation possibilities on D-Wave’s Quantum Annealers. Many test cases, with realistic constraints, have been considered to validate and characterise the potential of the model, and the promising results achieved are discussed throughout the document. The technical discussion is enriched with comparisons of the results obtained through heuristic algorithms, highlighting the strengths and the limitations in the resolution of the QUBO formulation proposed on current quantum machines

    A New Approach in the Management of Triangular Fossa Auricular Defects: The Posterior Auricular Artery Perforator Antihelix-Conchal Flap (PAAP Flap).

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    Background: The reconstruction of extensive scapha or triangular fossa defects to the ear still represents a challenge considering the lack of local simple surgical procedures. Objective: To present a new perforator flap which is a modification of the Elsahy and Ladocsi chondrocutaneous rotation flaps. Patients and Methods: Ten patients, in whom the oncological resection to the triangular fossa did not include cartilage, but skin and perichondrium. Defects no larger than 3 cm in diameter were treated. The dissection of the flap was carried out from lateral to medial on the anterior subperichondral plane. The flap was thus raised without the cartilage component but with the anterior perichondrium branched with the perforating vessels. Results: All flaps survived and treated patients presented good aesthetic results. Conclusions: We think that this procedure represents a valuable option to be considered in reconstructing well selected composite defects to upper ear

    anamorphic projection analogical digital algorithms

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    The study presents the first results of a wider research project dealing with the theme of "anamorphosis", a specific technique of geometric projection of a shape on a surface. Here we investigate how new digital techniques make it possible to simplify the anamorphic applications even in cases of projections on complex surfaces. After a short excursus of the most famous historical and contemporary applications, we propose several possible approaches for managing the geometry of anamorphic curves both in the field of descriptive geometry (by using interactive tools such as Cabri and GeoGebra) and during the complex surfaces realization process, from concept design to manufacture, through CNC systems (by adopting generative procedural algorithms elaborated in Grasshopper)

    Prevalence and attitudes to HIV testing among adults visiting public outpatient clinics in Rome: results of the MeDi (Measuring health Disparities in HIV prevention) survey. Part 1

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    Background. It is estimated that, in Italy, 12 000-18 000 (11-13% of 130 000) HIV-infected subjects are not aware of their serostatus. People in this condition may visit the healthcare system multiple times without being diagnosed. If tested on one of these occasions, they could modify their high-risk behaviours and benefit from treatment, factors that reduce HIV transmission. In Italy, no data on HIV testing in the general population are available so far and little is known on the relationship between socioeconomic determinants (at individual and neighbourhood levels) and testing uptake.Methods. A large anonymous survey was performed in 2012-2014 on more than 10 000 individuals 18-59 years old who underwent 21 public ambulatories in Rome to determine the proportion of subjects tested for HIV and factors related to testing uptake. Subjects’ socio-demographic characteristics, sexual orientation, number of sexual partners, HIV risk behaviour, HIV testing uptake were collected by a self-administered questionnaire. Level of area deprivation was measured at the postal code level by the index of social disadvantage (ISD). Multilevel Poisson regressions were carried out to take heterogeneity between clusters (post code and clinics) into account.Results. Among people participating in the study, 58.1% of subjects self-reported to have been tested at least once for HIV. Those who had one high risk behaviour for HIVinfection were 11% more likely to test than those not reporting any, and subjects who had had a STI (sexually-transmitted-infection) in the past were 12% more likely to test than those who had not had a STI. However only 44% (54% among subjects aged 18-35 years) of those with self-reported risks of contracting HIV had been tested at least once in life. This percentage increases, as expected, with the level of education, but, even so, about 40% of university educated subjects self-reporting risks of contracting HIV had never undergone an HIV test.Conclusions. This study highlights that, while the percentage of subjects tested is even higher than observed in other western nations, only 44% of subjects, self-reporting risks of contracting HIV, had tested at least once in life and about 40% of university educated subjects self reporting risks of contracting HIV had never tested.

    HIV prevalence among adults in Rome: results of the MeDi (Measuring health Disparities in HIV prevention) survey. Part 2

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    Background. In Italy, out of 60 millions of inhabitants, 3000 (2700-4000) new HIV infections are estimated each year. As combined antiretroviral therapy (ART) prolongs life for HIV sufferers, the prevalence of HIV-infection is likely to increase over time. Few studies have assessed factors associated with being HIV positive in people accessing public outpatient clinics and, in particular, the influence of socio-economic circumstances on HIV prevalence. This study aims to evaluate the association between subjects’ serostatus and socio-economic determinants measured at the individual and neighbourhood levels.Methods. Data from a large anonymous survey performed in 2012-2014 on more than 10 000 individuals 18-59 years old who underwent 21 public ambulatories in Rome were analysed. Subjects’ socio-demographic characteristics, sexual orientation, number of sexual partners, HIV risk behaviour and HIV testing uptake were collected by a selfadministered questionnaire. Level of area deprivation was measured at the postal code level by the index of social disadvantage (ISD). Multilevel Poisson regressions were carried out to take heterogeneity between clusters (post code and clinics) into account.Results. Self-reported HIV-prevalence was 2.0% among subjects ever been tested (13.7% for the homosexual/lesbians 7.0% for the bisexual and 1.3% for the heterosexual). About 1% of subjects self-identified as low risk was HIV infected. This prevalence increased up to 2% in the age group 18-34 and up to 5% in the non-heterosexuals (i.e. self- identified homosexuals/lesbians and bisexuals). At the individual level, HIV-prevalence decreased linearly from lowest to highest levels of education. Living in a deprived neighbourhood was not associated with HIV-infection.Conclusions. Our study confirms high HIV prevalences among homosexuals/lesbians. Some infections occur in subjects who do not report high risk behaviours for HIV transmission

    Targeting of PED/PEA-15 Molecular Interaction with Phospholipase D1 Enhances Insulin Sensitivity in Skeletal Muscle Cells

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    Phosphoprotein enriched in diabetes/phosphoprotein enriched in astrocytes (PED/PEA-15) is overexpressed in several tissues of individuals affected by type 2 diabetes. In intact cells and in transgenic animal models, PED/PEA-15 overexpression impairs insulin regulation of glucose transport, and this is mediated by its interaction with the C-terminal D4 domain of phospholipase D1 (PLD1) and the consequent increase of protein kinase C-alpha activity. Here we show that interfering with the interaction of PED/PEA-15 with PLD1 in L6 skeletal muscle cells overexpressing PED/PEA-15 (L6(PED/PEA-15)) restores insulin sensitivity. Surface plasmon resonance and ELISA-like assays show that PED/PEA-15 binds in vitro the D4 domain with high affinity (K(D) = 0.37 +/- 0.13 mum), and a PED/PEA-15 peptide, spanning residues 1-24, PED-(1-24), is able to compete with the PED/PEA-15-D4 recognition. When loaded into L6(PED/PEA-15) cells and in myocytes derived from PED/PEA-15-overexpressing transgenic mice, PED-(1-24) abrogates the PED/PEA-15-PLD1 interaction and reduces protein kinase C-alpha activity to levels similar to controls. Importantly, the peptide restores insulin-stimulated glucose uptake by approximately 70%. Similar results are obtained by expression of D4 in L6(PED/PEA-15). All these findings suggest that disruption of the PED/PEA-15-PLD1 molecular interaction enhances insulin sensitivity in skeletal muscle cells and indicate that PED/PEA-15 as an important target for type 2 diabetes

    Partitioned Paxos via the Network Data Plane

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    Consensus protocols are the foundation for building fault-tolerant, distributed systems, and services. They are also widely acknowledged as performance bottlenecks. Several recent systems have proposed accelerating these protocols using the network data plane. But, while network-accelerated consensus shows great promise, current systems suffer from an important limitation: they assume that the network hardware also accelerates the application itself. Consequently, they provide a specialized replicated service, rather than providing a general-purpose high-performance consensus that fits any off-the-shelf application. To address this problem, this paper proposes Partitioned Paxos, a novel approach to network-accelerated consensus. The key insight behind Partitioned Paxos is to separate the two aspects of Paxos, agreement, and execution, and optimize them separately. First, Partitioned Paxos uses the network forwarding plane to accelerate agreement. Then, it uses state partitioning and parallelization to accelerate execution at the replicas. Our experiments show that using this combination of data plane acceleration and parallelization, Partitioned Paxos is able to provide at least x3 latency improvement and x11 throughput improvement for a replicated instance of a RocksDB key-value store

    How the redox state regulates immunity

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    Oxidative stress is defined as an imbalance beween the levels of reactive oxygen species (ROS) and antioxidant defences. The view of oxidative stress as a cause of cell damage has evolved over the past few decades to a much more nuanced view of the role of oxidative changes in cell physiology. This is no more evident than in the field of immunity, where oxidative changes are now known to regulate many aspects of the immune response, and inflammatory pathways in particular. Our understanding of redox regulation of immunity now encompasses not only increases in reactive oxygen and nitrogen species, but also changes in the activities of oxidoreductase enzymes. These enzymes are important regulators of immune pathways both via changes in their redox activity, but also via other more recently identified cytokine-like functions. The emerging picture of redox regulation of immune pathways is one of increasing complexity and while therapeutic targeting of the redox environment to treat inflammatory disease is a possibility, any such strategy is likely to be more nuanced than simply inhibiting ROS production
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