879 research outputs found

    Multiple field-of-view MCAO for a Large Solar Telescope: LOST simulations

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    In the framework of a 4m class Solar Telescope we studied the performance of the MCAO using the LOST simulation package. In particular, in this work we focus on two different methods to reduce the time delay error which is particularly critical in solar adaptive optics: a) the optimization of the wavefront reconstruction by reordering the modal base on the basis of the Mutual Information and b) the possibility of forecasting the wavefront correction through different approaches. We evaluate these techniques underlining pros and cons of their usage in different control conditions by analyzing the results of the simulations and make some preliminary tests on real data.Comment: 10 pages, 5 figures to be published in Adaptive Optics Systems II (Proceedings Volume) Proceedings of SPI

    Inflation Risk, Wealth Expropriation and Governance Implications

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    With its often unperceived impact, interest rates and inflation volatility strongly affect long term stability within the firm, surreptitiously reshaping equilibria among different stakeholders and so raising key corporate governance concerns. Whereas the impact of interest rates and inflation on capital budgeting issues had been extensively analyzed, little attention has been paid to corporate governance implications, concerning key issues such as "optimal" (indexed) contracting, effective corporate ownership (messed up by wealth expropriation and redistribution), asset substitution or information asymmetries (embedded in hidden impacts on interest/inflation sensitive assets and liabilities). The topic is so theoretically and practically captivating, filling a gap in the existing literature and addressing real value protection targets, unassumingly crucial even for corporate ownership and control issues

    COMBINING NETWORK THEORY WITH CORPORATE GOVERNANCE: CONVERGING MODELS FOR CONNECTED STAKEHOLDERS

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    Traditional corporate governance patterns are based on the interaction among composite stakeholders and the various forms of separation between ownership and control. Stakeholders cooperate around the Coasian firm represented by a nexus of increasingly complex contracts. These well-known occurrences have been deeply investigated by growing literature and nurtured by composite empirical evidence. Apparently, unrelated network theory is concerned with the study of graphs as a representation of (a)symmetric relations between discrete objects (nodes connected by links). Network theory is highly interdisciplinary, and its versatile nature is fully consistent with the complex interactions of (networked) stakeholders, even in terms of game-theoretic patterns. The connection between traditional corporate governance issues and network theory properties is, however, still under-investigated. Hence the importance of an innovative reinterpretation that brings to "network governance". Innovation may, for instance, concern the principal-agent networked relationships and their conflicts of interest or the risk contagion and value drivers – three core governance issues. Networks and their applications (like blockchains, P2P platforms, game-theoretic interactions or digital supply chains) foster unmediated decentralization. In decentralized digital platforms stakeholders inclusively interact, promoting cooperation and sustainability. To the extent that network properties can be mathematically measured, governance issues may be quantified and traced with recursive patterns of expected occurrences

    Effect of Hypertension on Outcomes of High-Risk Patients After BCG-Treated Bladder Cancer

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    Immunotherapy with Bacillus Calmette Guerin (BCG) is the most efficacious treatment for high-risk bladder cancer (BC) (Ta/T1 or carcinoma in situ) to reduce the risk of recurrence. Our aim was to evaluate whether hypertension and diabetes influence the outcome of patients with noninvasive BC treated with BCG instillations. In order to collect homogeneous data, we considered as "hypertensive" only those patients who had previous diagnosed hypertension and a history of taking medical therapy with antihypertensive drugs (AHT), and as "diabetic" only those prescribed oral antidiabetics or insulin (ADT). We analyzed 343 high-risk BC patients undergoing BCG 1995 2010) with a median follow-up of 116 months (range 48-238). The distribution of various kinds of AHT and antidiabetic drugs was homogeneous, with no significant differences (p > 0.05). In both univariate and multivariate analyses, the only statistically significant parameter propostic for recurrence after BCG treatment was AHT. Recurrence-liee survival curves showed a significant correlation with AHT (p = 0.0168, hazards ratio [HR] 1.45, 95% confidence interval [CI] 1.0692-1.9619); there was no correlation ( p = 0.9040) with ADT (HR 0.9750, 95% CI 0.6457-1.4721). After stratification of AHT and A.DT according to drug(s) prescribed, there were no significant differences in the BC recurrence rate (p > 0.05). In this study with a very long-term follow-up, hypertension alone (evaluated by AHT) revealed the increased risk of BC recurrence after BCG treatment. Several hypotheses have been formulated to support these findings, but further prospective studies are needed to both evaluate the real influence of hypertension and identify a possible prognostic factor to be used in selecting poor-prognosis BC patients as early candidates for surgical treatment

    The impact of innovation and technology on microfinance sustainable governance

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    Technical or social innovation, concerning also the creation and commercialization of new products, strategies and management, has a deep actual - and especially trendy - impact on microfinance institutions (MFIs), contributing to reshape their business model, with an impact on their overall risk profile. Innovation is mostly an opportunity even for MF risk mitigation, considering its pervasive impact on risk factors. This original analysis is addressing, in a multidisciplinary and innovative comprehensive way, apparently weakly related topics such as MF governance, and IT issues, within recessionary cycles. This hardly investigated frontier faces key trendy issues, which are likely to deeply reengineer the relationship among different stakeholders, as it has already happened, on a different and more sophisticated scale, with traditional banking. To the extent that technology (with access to Internet, social networks, cashless electronic payments, etc.) reshapes the equilibriums among different stakeholders, it is likely to have important – albeit under-investigated - corporate governance consequences, softening the conflicts of interest among stakeholders and reinforcing the business model, making it more resilient during recessions, with positive externalities on both sustainability and outreach

    Entity Linking meets Word Sense Disambiguation: A Unified Approach

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    Entity Linking (EL) and Word Sense Disambiguation (WSD) both address the lexical ambiguity of language. But while the two tasks are pretty similar, they differ in a fundamental respect: in EL the textual mention can be linked to a named entity which may or may not contain the exact mention, while in WSD there is a perfect match between the word form (better, its lemma) and a suitable word sense. In this paper we present Babelfy, a unified graph-based approach to EL and WSD based on a loose identification of candidate meanings coupled with a densest subgraph heuristic which selects high-coherence semantic interpretations. Our experiments show state-ofthe-art performances on both tasks on 6 different datasets, including a multilingual setting. Babelfy is online at http://babelfy.orgEntity Linking (EL) and Word Sense Disambiguation (WSD) both address the lexical ambiguity of language. But while the two tasks are pretty similar, they differ in a fundamental respect: in EL the textual mention can be linked to a named entity which may or may not contain the exact mention, while in WSD there is a perfect match between the word form (better, its lemma) and a suitable word sense. In this paper we present Babelfy, a unified graph-based approach to EL and WSD based on a loose identification of candidate meanings coupled with a densest subgraph heuristic which selects high-coherence semantic interpretations. Our experiments show state-ofthe-art performances on both tasks on 6 different datasets, including a multilingual setting. Babelfy is online at http://babelfy.or

    Personalized Web Search via Query Expansion based on User’s Local Hierarchically-Organized Files

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    Users of Web search engines generally express information needs with short and ambiguous queries, leading to irrelevant results. Personalized search methods improve users’ experience by automatically reformulating queries before sending them to the search engine or rearranging received results, according to their specific interests. A user profile is often built from previous queries, clicked results or in general from the user’s browsing history; different topics must be distinguished in order to obtain an accurate profile. It is quite common that a set of user files, locally stored in sub-directory, are organized by the user into a coherent taxonomy corresponding to own topics of interest, but only a few methods leverage on this potentially useful source of knowledge. We propose a novel method where a user profile is built from those files, specifically considering their consistent arrangement in directories. A bag of keywords is extracted for each directory from text documents with in it. We can infer the topic of each query and expand it by adding the corresponding keywords, in order to obtain a more targeted formulation. Experiments are carried out using benchmark data through a repeatable systematic process, in order to evaluate objectively how much our method can improve relevance of query results when applied upon a third-party search engin

    Análise dialética da resistência a Phaeosphaeria maydis em milho

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    Em programas de melhoramento visando resistência genética a doenças, a estimativa de parâmetros genéticos que governam a resistência permite direcionar a introdução de resistência em germoplasmas. O objetivo deste trabalho foi estimar os efeitos heteróticos, a capacidade geral (CGC) e específica (CEC) de combinação, utilizando-se de dois métodos de avaliação da resistência, à Phaeosphaeria maydis através da análise dialélica de 36 híbridos F1 e de suas nove linhagens genitoras, em experimentos conduzidos em três ambientes. Foi utilizado um delineamento experimental em blocos casualizados com três repetições e a parcela experimental foi representada por uma fileira de 5 m. As diferenças entre as estimativas da capacidade de combinação, em diferentes ambientes e para os dois métodos de avaliação, apresentaram efeitos significativos (P < 0.01) para ambientes (E), CGC e CGC x E. O efeito de CEC e a interação CEC x E não foi significativa para os dois métodos de avaliação. Os efeitos de CGC foram mais importantes que CEC nesse conjunto de linhagens, sugerindo que efeitos genéticos aditivos são mais importantes como fonte de variação para resistência a esta doença. Efeitos heteróticos para resistência foram estimados, sendo possível identificar combinações híbridas específicas entre linhagens com alto potencial para o controle genético deste patógeno. Resultados para os dois métodos de avaliação foram praticamente idênticos, embora o método PI seja de maior praticidade de uso.In breeding programs directed towards genetic resistance against diseases, the estimation of genetic parameters that control resistance allows the introduction of resistance into suscetible germplasm to be clearly focused. The purposes of this study were to estimate heterosis effects, and the general (GCA) and specific (SCA) combining abilities by using two rating methods for resistance to Phaeosphaeria maydis in a diallel analysis of 36 F1 maize hybrids and their nine inbred lines. Trials were conducted in three environments. Disease severity was evaluated in the whole plant (PI) and in the leaf positioned just below the point of insertion of the main ear (AFA). The trials followed a randomized block design with plots represented by a 5 m long rows. Differences among combining ability estimates for different environments and in both evaluation methods showed significant effects (P < 0.01) for environment (E), GCA, and GCA × E. The SCA, and SCA × E effects were not significant for any of the disease severity variables. The GCA effects were more important than SCA for this set of inbred lines, suggesting that additive genetic effects are the most important sources of variation for this trait. Heterosis effects for resistance were estimated, and it was possible to identify specific hybrid combinations between lines which have high potential for genetic control of this pathogen. Results for both disease severity variables were practically identical, even though the PI method was more convenient to use
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