155 research outputs found

    Resource-driven Substructural Defeasible Logic

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    Linear Logic and Defeasible Logic have been adopted to formalise different features relevant to agents: consumption of resources, and reasoning with exceptions. We propose a framework to combine sub-structural features, corresponding to the consumption of resources, with defeasibility aspects, and we discuss the design choices for the framework

    Combining Effects and Coeffects via Grading

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    This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by the Association for Computing Machinery.Effects\textit{Effects} and coeffects\textit{coeffects} are two general, complementary aspects of program behaviour. They roughly correspond to computations which change the execution context (effects) versus computations which make demands on the context (coeffects). Effectful features include partiality, non-determinism, input-output, state, and exceptions. Coeffectful features include resource demands, variable access, notions of linearity, and data input requirements. The effectful or coeffectful behaviour of a program can be captured and described via type-based analyses, with fine grained information provided by monoidal effect annotations and semiring coeffects. Various recent work has proposed models for such typed calculi in terms of graded (strong) monads\textit{graded (strong) monads} for effects and graded (monoidal) comonads\textit{graded (monoidal) comonads} for coeffects. Effects and coeffects have been studied separately so far, but in practice many computations are both effectful and coeffectful, e.g., possibly throwing exceptions but with resource requirements. To remedy this, we introduce a new general calculus with a combined effect-coeffect system\textit{effect-coeffect system}. This can describe both the changes\textit{changes} and requirements\textit{requirements} that a program has on its context, as well as interactions between these effectful and coeffectful features of computation. The effect-coeffect system has a denotational model in terms of effect-graded monads and coeffect-graded comonads where interaction is expressed via the novel concept of graded distributive laws\textit{graded distributive laws}. This graded semantics unifies the syntactic type theory with the denotational model. We show that our calculus can be instantiated to describe in a natural way various different kinds of interaction between a program and its evaluation context.Orchard was supported by EPSRC grant EP/M026124/1 and EP/K011715/1 (whilst previously at Imperial College London), Katsumata by JSPS KAKENHI grant JP15K00014, Uustalu by Estonian Min. of Educ. and Res. grant IUT33-13 and Estonian Sci. Found. grant 9475. Gaboardi’s work was done in part while at the University of Dundee, UK supported by EPSRC grant EP/M022358/1

    Are Urologists Ready for Interpretation of Multiparametric MRI Findings? A Prospective Multicentric Evaluation

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    Aim: To assess urologists’ proficiency in the interpretation of multiparametric magnetic resonance imaging (mpMRI). Materials and Methods: Twelve mpMRIs were shown to 73 urologists from seven Italian institutions. Responders were asked to identify the site of the suspicious nodule (SN) but not to assign a PIRADS score. We set an a priori cut-off of 75% correct identification of SN as a threshold for proficiency in mpMRI reading. Data were analyzed according to urologists’ hierarchy (UH; resident vs. consultant) and previous experience in fusion prostate biopsies (E-fPB, defined as <125 vs. ≥125). Additionally, we tested for differences between non-proficient vs. proficient mpMRI readers. Multivariable logistic regression analyses (MVLRA) tested potential predictors of proficiency in mpMRI reading. Results: The median (IQR) number of correct identifications was 8 (6–8). Anterior nodules (number 3, 4 and 6) represented the most likely prone to misinterpretation. Overall, 34 (47%) participants achieved the 75% cut-off. When comparing consultants vs. residents, we found no differences in terms of E-fPB (p = 0.9) or in correct identification rates (p = 0.6). We recorded higher identification rates in urologists with E-fBP vs. their no E-fBP counterparts (75% vs. 67%, p = 0.004). At MVLRA, only E- fPB reached the status of independent predictor of proficiency in mpMRI reading (OR: 3.4, 95% CI 1.2–9.9, p = 0.02) after adjusting for UH and type of institution. Conclusions: Despite urologists becoming more familiar with interpretation of mpMRI, their results are still far from proficient. E-fPB enhances the proficiency in mpMRI interpretation

    Global and local space properties of stream programs

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    The original publication is available at www.springerlink.comInternational audienceIn this paper, we push forward the approach proposed in [1] aiming at studying semantic interpretation criteria for the purpose of ensuring safety and complexity properties of programs working on streams. The paper improves the previous results by considering global and local upper bounds properties of both theoretical and practical interests guaranteeing that the size of each output stream element is bounded by a function in the maximal size of the input stream elements. Moreover, in contrast to previous studies, these properties also apply to a wide class of stream definitions, that is functions that do not have streams in the input but produce an output stream

    Surgical activity in the COVID-19 era. Trend of slowdown from a multicentre observational study

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    COVID-19 outbreak represented an unprecedented event that led to a redefinition of health care systems worldwide. The impact of the emergency required a deviation of the care toward the assistance to COVID-19 patients, with reduction of resources for elective activities, including surgery. We aim to report the decrease of urological surgical activity during the first weeks from the beginning of the pandemic, aiming to highlight the prioritization we applied to select patients for surgery

    Psychometric properties of the measure of achieved capabilities in homeless services

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    Background Purposeful participation in personally meaningful life tasks, enjoyment of positive reciprocal relationships, and opportunities to realize one’s potential are growth-related aspects of a meaningful life that should be considered important dimensions of recovery from homelessness. The extent to which homeless services support individuals to achieve the capabilities they need to become who they want to be and do what they want to do is, in turn, an important indicator of their efectiveness. In this study, we developed a measure of achieved capabilities (MACHS) for use in homeless services settings, and assessed its construct and concurrent validity. Methods We analysed data collected from homeless services users at two time points in eight European countries to assess the factor structure and psychometric properties of the new measure. Participants were adults engaged with either Housing First (n=245) or treatment as usual (n=320). Results Exploratory and confrmatory factor analyses yielded a four-factor structure of the capabilities measure: community integration, optimism, safety, and self-determination. We obtained evidence for construct validity through observed correlations between achieved capabilities and recovery, working alliance and satisfaction with services. Moreover, we obtained evidence of the measure’s concurrent validity from its positive association between HF and personal recovery, which was fully mediated by achieved capabilities. Conclusions Findings demonstrate that the MACHS is a valid and reliable measure that may be used to assess the extent to which homeless services support their clients to develop capabilities needed for growth-related recovery. Implications for practice and future research directions are discussed.info:eu-repo/semantics/publishedVersio

    The dramatic COVID-19 outbreak in italy is responsible of a huge drop in urological surgical activity: A multicenter observational study

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    OBJECTIVE: Italy is facing the COVID-19 outbreak with an abrupt reorganization of its national health-system, in order to augment care provision to symptomatic patients. The sudden shift of personnel and resources towards COVID-19 care has led to the reduction of surgery, with possible severe drawbacks. The aim of the study is to describe the trend in surgical volume in urology, in Italy. MATERIALS AND METHODS: Thirty-three urological units with physicians affiliated to the AGILE consortium were involved in a survey. Urologists were asked to report the amount of surgical elective procedures week-by-week, from the beginning of the emergency to the following month. RESULTS: The 33 hospitals involved in the study account, globally, for 22,945 beds and are distributed in 13/20 Italian regions. Before the outbreak, the involved urology units performed an overall amount of 1,213 procedures per week, half of which were oncological. One month later, the amount of surgery declined by 78%. Lombardy, the first region with positive-cases, experienced a 94% reduction. The decrease in oncological and non-oncological surgical activity was 35,9% and 89%, respectively. The trend of the decline showed a delay of roughly 2 weeks for the other regions. CONCLUSION: Italy, the country with the highest fatality rate from COVID-19, is experiencing a sudden decline in surgical activity. It is inversely related to the increase in COVID-19 care, with potential harm particularly in the oncological field. The Italian experience can be helpful for future surgical pre-planning in other countries not so hardly hit by the disease yet

    Early Oncologic Failure after Robot-Assisted Radical Cystectomy: Results from the International Robotic Cystectomy Consortium

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    PURPOSE: We sought to investigate the prevalence and variables associated with early oncologic failure. MATERIALS AND METHODS: We retrospectively reviewed the IRCC (International Radical Cystectomy Consortium) database of patients who underwent robot-assisted radical cystectomy since 2003. The final cohort comprised a total of 1,894 patients from 23 institutions in 11 countries. Early oncologic failure was defined as any disease relapse within 3 months of robot-assisted radical cystectomy. All institutions were surveyed for the pneumoperitoneum pressure used, breach of oncologic surgical principles, and techniques of specimen and lymph node removal. A multivariate model was fit to evaluate predictors of early oncologic failure. The Kaplan-Meier method was applied to depict disease specific and overall survival, and Cox proportional regression analysis was used to evaluate predictors of disease specific and overall survival. RESULTS: A total of 305 patients (22%) experienced disease relapse, which was distant in 220 (16%), local recurrence in 154 (11%), peritoneal carcinomatosis in 17 (1%) and port site recurrence in 5 (0.4%). Early oncologic failure developed in 71 patients (5%) at a total of 10 institutions. The incidence of early oncologic failure decreased from 10% in 2006 to 6% in 2015. On multivariate analysis the presence of any complication (OR 2.87, 95% CI 1.38–5.96, p = 0.004), pT3 or greater disease (OR 3.73, 95% CI 2.00–6.97, p <0.001) and nodal involvement (OR 2.14, 95% CI 1.21–3.80, p = 0.008) was a significant predictor of early oncologic failure. Patients with early oncologic failure demonstrated worse disease specific and overall survival (23% and 13%, respectively) at 1 and 3 years compared to patients who experienced later or no recurrences (log rank p <0.001). CONCLUSIONS: The incidence of early oncologic failure following robot-assisted radical cystectomy has decreased with time. Disease related rather than technical related factors have a major role in early oncologic failure after robot-assisted radical cystectomy

    Update of the ICUD-SIU consultation on upper tract urothelial carcinoma 2016: treatment of low-risk upper tract urothelial carcinoma

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    Introduction The conservative management of upper tract urothelial carcinoma (UTUC) has historically been offered to patients with imperative indications. The recent International Consultation on Urologic Diseases (ICUD) publication on UTUC stratified treatment allocations based on high- and low-risk groups. This report updates the conservative management of the low-risk group. Methods The ICUD for low-risk UTUC working group performed a thorough review of the literature with an assessment of the level of evidence and grade of recommendation for a variety of published studies in this disease space. We update these publications and provide a summary of that original report. Results There are no prospective randomized controlled studies to support surgical management guidelines. A risk-stratified approach based on clinical, endoscopic, and biopsy assessment allows selection of patients who could benefit from kidney-preserving procedures with oncological outcomes potentially similar to radical nephroureterectomy with bladder cuff excision, with the added benefit of renal function preservation. These treatments are aided by the development of high-definition flexible digital URS, multi-biopsies with the aid of access sheaths and other tools, and promising developments in the use of adjuvant topical therapy. Conclusions Recent developments in imaging, minimally invasive techniques, multimodality approaches, and adjuvant topical regimens and bladder cancer prevention raise the hope for improved risk stratification and may greatly improve the endoscopic treatment for low-risk UTUC
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