Multi-scale colorectal tumour segmentation using a novel coarse to fine strategy

This paper addresses the problem of colorectal tumour segmentation in complex real world imagery. For efficient segmentation, a multi-scale strategy is developed for extracting the potentially cancerous region of interest (ROI) based on colour histograms while searching for the best texture resolution. To achieve better segmentation accuracy, we apply a novel bag-of-visual-words method based on rotation invariant raw statistical features and random projection based l2-norm sparse representation to classify tumour areas in histopathology images. Experimental results on 20 real world digital slides demonstrate that the proposed algorithm results in better recognition accuracy than several state of the art segmentation techniques.

Studio multi-banda dal sub-parsec al kilo-parsec dell'emissione del getto nella radio galassia IC 1531

In questo lavoro di tesi si presenta il primo studio multi-scala e multi-frequenza focalizzato sul getto della radiogalassia IC1531 (z=0.026) con i satelliti Chandra, XMM-Newton e Fermi con l’obiettivo di tracciarne l’emissione alle alte energie; definire i processi radiativi responsabili dell’emissione osservata e stimare i principali parametri fisici del getto; stimare l’energetica del getto alle diverse scale. La sorgente è stata selezionata per la presenza di un getto esteso (≈5’’) osservato in radio e ai raggi X, inoltre, era riportata come possibile controparte della sorgente gamma 3FGLJ0009.6-3211 presente nel terzo catalogo Fermi (3FGL). La presenza di emissione ai raggi γ, confermata dal nostro studio, è importante per la modellizzazione della SED della regione nucleare. L’emissione X del nucleo è dominata da una componente ben riprodotta da una legge di potenza con indice spettrale Γ=2.2. L’analisi dell’emissione in banda gamma ha evidenziato una variabilità su scale di 5 giorni, dalla quale è stato possibile stimare le dimensioni delle regione emittente. Inoltre viene presentato lo studio della distribuzione spettrale dell’energia della regione nucleare di IC 1531 dalla banda radio ai raggi γ. I modelli ci permettono di determinare la natura dell’emissione gamma e stimare la potenza cinetica del getto a scale del su-pc. Gli osservabili sono stati utilizzati per ottenere le stime sui parametri del modello. La modellizzazione così ottenuta ha permesso di stimare i parametri fisici del getto e la potenza trasportata del getto a scale del sub-pc. Le stime a 151MHz suggerisco che il getto abbia basse velocita' (Γ≤7) e angolo di inclinazione rispetto alla linea di vista 10°<ϑ<20°; nel complesso, il trasporto di energia da parte del getto risulta efficiente. L’origine dell’emissione X del getto a grandi scale è consistente con un’emissione di sincrotrone, che conferma la classificazione di IC1531 come sorgente di bassa potenza MAGN.

Team Member’s Centrality, Cohesion, Conflict, and Performance in Multi-University Geographically Distributed Project Teams

This study examined team processes and outcomes among 12 multi-university distributed project teams from 11 universities during its early and late development stages over a 14-month project period. A longitudinal model of team interaction is presented and tested at the individual level to consider the extent to which both formal and informal network connections—measured as degree centrality—relate to changes in team members’ individual perceptions of cohesion and conflict in their teams, and their individual performance as a team member over time. The study showed a negative network centrality-cohesion relationship with significant temporal patterns, indicating that as team members perceive less degree centrality in distributed project teams, they report more team cohesion during the last four months of the project. We also found that changes in team cohesion from the first three months (i.e., early development stage) to the last four months (i.e., late development stage) of the project relate positively to changes in team member performance. Although degree centrality did not relate significantly to changes in team conflict over time, a strong inverse relationship was found between changes in team conflict and cohesion, suggesting that team conflict emphasizes a different but related aspect of how individuals view their experience with the team process. Changes in team conflict, however, did not relate to changes in team member performance. Ultimately, we showed that individuals, who are less central in the network and report higher levels of team cohesion, performed better in distributed teams over time.

Elaborazione di un modello di simulazione per una rete di trasporto multi-modale

Questo lavoro di tesi si prefigge l’obiettivo di simulare il trasporto di organi destinati a trapianto sul territorio nazionale italiano. Lo scopo della simulazione è mettere in luce le criticità e le eventuali soluzioni alternative in modo da raggiungere un duplice obiettivo: la certezza di portare a compimento il trasporto da un ospedale ad un altro entro i tempi clinici necessari affinché l’organo sia ancora utilizzabile e la riduzione dei costi del trasporto, che negli ultimi anni si sono rivelati elevati a causa del ricorso frequente a voli di Stato. Nella prima parte del lavoro viene delineato il problema e le necessità di ottimizzazione della rete, dopodiché si illustra il modello creato per simulare la situazione di as-is ed infine si espone il modello da utilizzare in futuro, dove si prevedono i tempi futuri di percorrenza. Per la modellazione della situazione attuale sono stati utilizzati due livelli di dettaglio diversi, uno che si basa sulla suddivisione dei trapianti in ingresso e uscita da una regione specifica e uno che approfondisce ulteriormente la rete modellando gli spostamenti di città in città. I modelli predittivi presentati sono due, uno che considera tempi predittivi deterministici e uno che considera tempi stocastici. Dopo ciascuna modellazione vengono esposti i risultati e le statistiche più significative; vengono infine messi in evidenza gli aspetti critici e gli sviluppi futuri della simulazione. Il software scelto per creare e simulare il trasporto degli organi sulla rete è Arena.

Design Without Borders: A Multi-Everything Masters

Design is increasingly a global activity: addressing issues that challenge and affect people and populations other than our own, involving stakeholders from many cultures, realized through borderless networks of knowledge, services, materials, manufacturing and distribution. There is an appetite among graduates, especially in design and engineering, to broaden horizons and raise ambitions, to tackle big issues through innovation to bring about life-changing or world-changing impact. Employers demand such thinkers and doers: culturally attuned, multidisciplinary and T-shaped, unafraid to shake things up. In 2013, twelve postgraduates embarked on a new joint Masters course in London; students from eight different nations, studying together in three capital cities over two years. This programme is a collaboration between four centres of academic excellence in UK, USA and Japan; these students soon become its first graduating cohort, having experienced differing teaching styles, perspectives and specialisms around design, technology and innovation from four world-class institutions; immersion in three very different cultures; collaboration with students and faculty from many diverse disciplines and cultures; forming friendships and networks spanning the globe. This paper outlines the rationale and philosophy of the course, the challenges in its realisation and development so far, and its likely future evolution.

Information and Communication Technologies (ICT) to Improve Prescription Appropriateness and Therapy Adherence in the Multi-morbid Elderly

Multimorbidity patients pose severe challenges to which information and communication technology (ICT) can help patients and doctors to answer with effective and efficient care.

Acute Q Fever Presenting with Multi-Organ Failure: Re-Evaluation of the Initial Diagnosis

We present the case of a 48-year-old man admitted to the critical care unit with atrial fibrillation, and acute heart and kidney failure accompanied by coagulopathy and an abnormal liver test. Initially diagnosed as a non-ST elevation myocardial infarction, re-evaluation of the case led to the consideration of severe sepsis. Q fever and leptospirosis were the most probable causes and empiric treatment was initiated. A complete recovery was achieved following treatment.

Ventricular Fibrillation in Patient with Multi-vessel Coronary Spasm Four Days after the Initiation of Oral Beta-blocker

We describe a case of ventricular fibrillation occurring in a patient with multi-vessel coronary spasm after the initiation of an oral beta-blocker. A 56-year-old man began to experience chest discomfort and his computed tomography revealed intermediate coronary stenoses. He was administered medications including an oral beta-blocker but suddenly collapsed while walking 4 days later. An automated external defibrillator detected ventricular fibrillation and delivered successful electrical cardioversion. An acetylcholine provocation test after stabilization of the status revealed triple-vessel coronary spasm. Beta-blockers may provoke exacerbation of coronary spasm and result in lethal arrhythmia.

A Case Against Fancy Decorated Drinks: Multi-Organ Failure After Drinking a Mojito Cocktail

We present the first case of gastro-intestinal perforation caused by a mint twig decorating a cocktail drink. A 76-year-old man was enjoying his Mojito cocktail on a cruise ship near Mexico when he accidently swallowed a mint twig, resulting in ileum perforation. This led to a cascade of events, eventually resulting in life-threatening multi-organ failure. Given this rare but potentially severe complication and the increasing popularity of decorated drinks, a less ‘fancy’ presentation for cocktails and similar drinks may be warranted.

Evaluation of the cytotoxic and genotoxic effects of benchmark multi-walled carbon nanotubes in relation to their physicochemical properties

To contribute with scientific evidence to the grouping strategy for the safety assessment of multi-walled carbon nanotubes (MWCNTs), this work describes the investigation of the cytotoxic and genotoxic effects of four benchmark MWCNTs in relation to their physicochemical characteristics, using two types of human respiratory cells. The cytotoxic effects were analysed using the clonogenic assay and replication index determination. A 48h-exposure of cells revealed that NM-401 was the only cytotoxic MWCNT in both cell lines, but after 8-days exposure, the clonogenic assay in A549 cells showed cytotoxic effects for all the tested MWCNTs. Correlation analysis suggested an association between the MWCNTs size in cell culture medium and cytotoxicity. No induction of DNA damage was observed after any MWCNTs in any cell line by the comet assay, while the micronucleus assay revealed that both NM-401 and NM-402 were genotoxic in A549 cells. NM-401 and NM-402 are the two longest MWCNTs analyzed in this work, suggesting that length may be determinant for genotoxicity. No induction of micronuclei was observed in Beas-2B cell line and the different effect in both cell lines is explained in view of the size-distribution of MWCNTs in the cell culture medium, rather than cell's specificities.

Feasibility study and flow scheduling optimization of a multi-product pipeline system

The first goal of this study is to analyse a real-world multiproduct onshore pipeline system in order to verify its hydraulic configuration and operational feasibility by constructing a simulation model step by step from its elementary building blocks that permits to copy the operation of the real system as precisely as possible. The second goal is to develop this simulation model into a user-friendly tool that one could use to find an “optimal” or “best” product batch schedule for a one year time period. Such a batch schedule could change dynamically as perturbations occur during operation that influence the behaviour of the entire system. The result of the simulation, the ‘best’ batch schedule is the one that minimizes the operational costs in the system. The costs involved in the simulation are inventory costs, interface costs, pumping costs, and penalty costs assigned to any unforeseen situations. The key factor to determine the performance of the simulation model is the way time is represented. In our model an event based discrete time representation is selected as most appropriate for our purposes. This means that the time horizon is divided into intervals of unequal lengths based on events that change the state of the system. These events are the arrival/departure of the tanker ships, the openings and closures of loading/unloading valves of storage tanks at both terminals, and the arrivals/departures of trains/trucks at the Delivery Terminal. In the feasibility study we analyse the system’s operational performance with different Head Terminal storage capacity configurations. For these alternative configurations we evaluated the effect of different tanker ship delay magnitudes on the number of critical events and product interfaces generated, on the duration of pipeline stoppages, the satisfaction of the product demand and on the operative costs. Based on the results and the bottlenecks identified, we propose modifications in the original setup.

Swedish-speaking Finns: a multi-method qualitative study of belonging and identification

The Swedish-speaking minority in Finland, often described as an ‘elite minority’, holds a special position in the country. With linguistic rights protected by the constitution of Finland, Swedish-speakers, as a minority of only 5.3%, are often described in public discourse and in academic and statistical studies as happier, healthier and more well off economically than the Finnish-speaking majority. As such, the minority is a unique example of language minorities in Europe. Knowledge derived from qualitatively grounded studies on the topic is however lacking, meaning that there is a gap in understanding of the nature and complexity of the minority. Drawing on ethnographic research conducted in four different locations in Finland over a period of 12 months, this thesis provides a theoretically grounded and empirically informed rich account of the identifications and sites of belonging of this diverse minority. The thesis makes a contribution to theoretical, methodological and empirical research on the Swedish-speaking minority, debates around identity and belonging, and ethnographic methodological approaches. Making use of novel methodology in studying Swedish-speaking Finns, this thesis moves beyond generalisations and simplifications on its nature and character. Drawing on rich ethnographic empirical material, the thesis interrogates various aspects of the lived experience of Swedish-speaking Finns by combining the concepts of belonging and identification. Some of the issues explored are the way in which belonging can be regionally specific, how Swedish-speakers create Swedish-spaces, how language use is situational and variable and acts as a marker of identity, and finally how identifications and sites of belonging among the minority are extremely varied and complex. The thesis concludes that there are various sites of belonging and identification available to Swedish-speakers, and these need to be studied and considered in order to gain an accurate picture of the lived experience of the minority. It also argues that while identifications are based on collective imagery, this imagery can vary among Swedish-speakers and identifications are multiple and situational. Finally, while language is a key commonality for the minority, the meanings attached to it are not only concerned with ‘Finland Swedishness’, but connected to various other factors, such as the context a person grew up in and the region one lives in. The complex issues affecting the lived experience of Swedish-speaking Finns cannot be understood without the contribution of findings from qualitative research. This thesis therefore points towards a new kind of understanding of Swedish-speaking Finns, moving away from stereotypes and simplifications, shifting our gaze towards a richer perception of the minority.

Analisi multi-obiettivo in ottica lean-green della reverse logistics dei veicoli a fine vita (ELV)

La gestione del fine vita dei prodotti è un argomento di interesse attuale per le aziende; sempre più spesso l’imprese non possono più esimersi dall’implementare un efficiente sistema di Reverse Logistics. Per rispondere efficacemente a queste nuove esigenze diventa fondamentale ampliare i tradizionali sistemi logistici verso tutte quelle attività svolte all’interno della Reverse Logitics. Una gestione efficace ed efficiente dell’intera supply chain è un aspetto di primaria importanza per un’azienda ed incide notevolmente sulla sua competitività; proprio per perseguire questo obiettivo, sempre più aziende promuovono politiche di gestione delle supply chain sia Lean che Green. L’obiettivo di questo lavoro, nato dalle esigenze descritte sopra, è quello di applicare un modello innovativo che consideri sia politiche di gestione Lean, che dualmente politiche Green, alla gestione di una supply chain del settore automotive, comprendente anche le attività di gestione dei veicoli fuori uso (ELV). Si è analizzato per prima cosa i principi base e gli strumenti utilizzati per l’applicazione della Lean Production e del Green supply chain management e in seguito si è analizzato le caratteristiche distintive della Reverse Logistics e in particolare delle reti che trattano i veicoli a fine vita. L’obiettivo finale dello studio è quello di elaborare e implementare, tramite l’utilizzo del software AMPL, un modello di ottimizzazione multi-obiettivo (MOP- Multi Objective Optimization) Lean e Green a una Reverse Supply Chain dei veicoli a fine vita. I risultati ottenuti evidenziano che è possibile raggiungere un ottimo compromesso tra le due logiche. E' stata effettuata anche una valutazione economica dei risultati ottenuti, che ha evidenziato come il trade-off scelto rappresenti anche uno degli scenari con minor costi.

Aragonite-based scaffold for the treatment of knee osteochondral defects: results of a prospective multi-center trial at 2 years' follow-up

PURPOSE: To evaluate the clinical and MRI outcomes after the implantation of a nanostructured cell free aragonite-based scaffold in patients affected by knee chondral and osteochondral lesions. METHODS: 126 patients (94 men, 32 women; age 32.7±8.8 years) were included according to the following criteria: grade III or IV chondra/osteochondral lesions in the femoral condyles or throclea; 2) no limb axial deviation (i.e. varus or valgus knee > 5°); 3) no signs of knee instability; 4) no concurrent tibial or patellar chondral/osteochondral defects. All patients were treated by arthrotomic implantation of an aragonite based-scaffold by a press-fit technique. Patients were prospectively evaluated by IKDC, Tegner, Lysholm and KOOS scores preoperatively and then at 6, 12, 18 and 24-months follow-up. MRI was also performed to evaluate the amount of defect filling by regenerated cartilage. Failures were defined as the need for re-intervention in the index knee within the follow-up period. RESULTS: Average defect size was 2±1.3 cm2 and in most cases a single scaffold was used. A significant improvement in each clinical score was recorded from basal level to 24 months’ follow-up. In particular, the IKDC subjective score increased from 42.14±16 to 70.94±24.69 and the Tegner score improved from 2.95±1.90 to 4.82±1.85 (p<0.0005). Lysholm score and all the subscales of KOOS showed a similar trend over time. Age of the patient at implantation, size of the defect and BMI were correlated with lower clinical outcome. The presence of OA didn’t influence the clinical results. MRI evaluation showed a significant increase in defect filling over time, with the highest value reached at 24 months. Failures occurred in eleven patients (8.7%). CONCLUSION: The aragonite-based biomimetic osteochondral scaffold proved to be safe, and encouraging clinical and radiographic outcomes were documented up to 2 years’ follow-up.