1,158 research outputs found

    From data to applications in the Internet of Things

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    Con la crescita in complessità delle infrastrutture IT e la pervasività degli scenari di Internet of Things (IoT) emerge il bisogno di nuovi modelli computazionali basati su entità autonome capaci di portare a termine obiettivi di alto livello interagendo tra loro grazie al supporto di infrastrutture come il Fog Computing, per la vicinanza alle sorgenti dei dati, e del Cloud Computing per offrire servizi analitici complessi di back-end in grado di fornire risultati per milioni di utenti. Questi nuovi scenarii portano a ripensare il modo in cui il software viene progettato e sviluppato in una prospettiva agile. Le attività dei team di sviluppatori (Dev) dovrebbero essere strettamente legate alle attività dei team che supportano il Cloud (Ops) secondo nuove metodologie oggi note come DevOps. Tuttavia, data la mancanza di astrazioni adeguata a livello di linguaggio di programmazione, gli sviluppatori IoT sono spesso indotti a seguire approcci di sviluppo bottom-up che spesso risulta non adeguato ad affrontare la compessità delle applicazione del settore e l'eterogeneità dei compomenti software che le formano. Poichè le applicazioni monolitiche del passato appaiono difficilmente scalabili e gestibili in un ambiente Cloud con molteplici utenti, molti ritengono necessaria l'adozione di un nuovo stile architetturale, in cui un'applicazione dovrebbe essere vista come una composizione di micro-servizi, ciascuno dedicato a uno specifica funzionalità applicativa e ciascuno sotto la responsabilità di un piccolo team di sviluppatori, dall'analisi del problema al deployment e al management. Poichè al momento non si è ancora giunti a una definizione univoca e condivisa dei microservices e di altri concetti che emergono da IoT e dal Cloud, nè tantomento alla definzione di linguaggi sepcializzati per questo settore, la definzione di metamodelli custom associati alla produzione automatica del software di raccordo con le infrastrutture potrebbe aiutare un team di sviluppo ad elevare il livello di astrazione, incapsulando in una software factory aziendale i dettagli implementativi. Grazie a sistemi di produzione del sofware basati sul Model Driven Software Development (MDSD), l'approccio top-down attualmente carente può essere recuperato, permettendo di focalizzare l'attenzione sulla business logic delle applicazioni. Nella tesi viene mostrato un esempio di questo possibile approccio, partendo dall'idea che un'applicazione IoT sia in primo luogo un sistema software distribuito in cui l'interazione tra componenti attivi (modellati come attori) gioca un ruolo fondamentale

    Assessment, surgeon, and society

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    An increasing public demand to monitor and assure the quality of care provided by physicians and surgeons has been accompanied by a deepening appreciation within the profession of the demands of self-regulation and the need for accountability. To respond to these developments, the public and the profession have turned increasingly to assessment, both to establish initial competence and to ensure that it is maintained throughout a career. Fortunately, this comes at a time when there have been significant advances in the breadth and quality of the assessment tools available. This article provides an overview of the drivers of change in assessment which includes the educational outcomes movement, the development of technology, and advances in assessment. It then outlines the factors that are important in selecting assessment devices as well as a system for classifying the methods that are available. Finally, the drivers of change have spawned a number of trends in the assessment of competence as a surgeon. Three of them are of particular note, simulation, workplace-based assessment, and the assessment of new competences, and each is reviewed with a focus on its potential

    Supraspinal Gbetagamma-dependent stimulation of PLCbeta originating from G inhibitory protein-mu opioid receptor-coupling is necessary for morphine induced acute hyperalgesia.

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    Although alterations in μ-opioid receptor signaling mediate excitatory effects of opiates in opioid tolerance, the molecular mechanism for the excitatory effect of acute low dose morphine, as it relates to μ-opioid receptor coupling, is presently unknown. A pronounced coupling of μ-opioid receptor to the α subunit of G inhibitory protein emerged in periaqueductal gray from mice systemically administered with morphine at a dose producing acute thermal hyperalgesia. This coupling was abolished in presence of the selective μ-opioid receptor receptor antagonist CTOP administered at the periaqueductal gray site, showing that the low dose morphine effect is triggered by μ-opioid receptor activated G inhibitory protein at supraspinal level. When Gβγ downstream signalling was blocked by intra-periaqueductal gray co-administration of M119, a compound that inhibits Gβγ dimer-dependent signaling, a complete prevention of low dose morphine induced acute thermal hyperalgesia was obtained. Phospholipase C β3, an enzyme necessary to morphine hyperalgesia, was revealed to be associated with Gβγ in periaqueductal gray. Although opioid administration induces a shift in μ-opioid receptor-G protein coupling from Gi to Gs after chronic administration, our data support that this condition is not realized in acute treatment providing evidence that a separate molecular mechanism underlies morphine induced acute excitatory effect

    Peer assessment of competence

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    Objective This instalment in the series on professional assessment summarises how peers are used in the evaluation process and whether their judgements are reliable and valid. Method The nature of the judgements peers can make, the aspects of competence they can assess and the factors limiting the quality of the results are described with reference to the literature. The steps in implementation are also provided. Results Peers are asked to make judgements about structured tasks or to provide their global impressions of colleagues. Judgements are gathered on whether certain actions were performed, the quality of those actions and ⁄ or their suitability for a particular purpose. Peers are used to assess virtually all aspects of professional competence, including technical and nontechnical aspects of proficiency. Factors influencing the quality of those assessments are reliability, relationships, stakes and equivalence. Conclusion Given the broad range of ways peer evaluators can be used and the sizeable number of competencies they can be asked to judge, generalisations are difficult to derive and this form of assessment can be good or bad depending on how it is carried out

    Precision measurement of Compton scattering in silicon with a skipper CCD for dark matter detection

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    Experiments aiming to directly detect dark matter through particle recoils can achieve energy thresholds of O(10  eV). In this regime, ionization signals from small-angle Compton scatters of environmental γ rays constitute a significant background. Monte Carlo simulations used to build background models have not been experimentally validated at these low energies. We report a precision measurement of Compton scattering on silicon atomic shell electrons down to 23 eV. A skipper charge-coupled device with single-electron resolution, developed for the DAMIC-M experiment, was exposed to a 241Am γ-ray source over several months. Features associated with the silicon K-, L1-, and L2,3-shells are clearly identified, and scattering on valence electrons is detected for the first time below 100 eV. We find that the relativistic impulse approximation for Compton scattering, which is implemented in Monte Carlo simulations commonly used by direct detection experiments, does not reproduce the measured spectrum below 0.5 keV. The data are in better agreement with ab initio calculations originally developed for x-ray absorption spectroscopy
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