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11.
Marcelo Arenas Jorge Pérez Juan Reutter Cristian Riveros 《The VLDB Journal The International Journal on Very Large Data Bases》2012,21(6):823-842
The inversion of schema mappings has been identified as one of the fundamental operators for the development of a general framework for metadata management. During the last few years, three alternative notions of inversion for schema mappings have been proposed (Fagin-inverse (Fagin, TODS 32(4), 25:1–25:53, 2007), quasi-inverse (Fagin et?al., TODS 33(2), 11:1–11:52, 2008), and maximum recovery (Arenas et?al., TODS 34(4), 22:1–22:48, 2009)). However, these notions lack some fundamental properties that limit their practical applicability: most of them are expressed in languages including features that are difficult to use in practice, some of these inverses are not guaranteed to exist for mappings specified with source-to-target tuple-generating dependencies (st-tgds), and it has been futile to search for a meaningful mapping language that is closed under any of these notions of inverse. In this paper, we develop a framework for the inversion of schema mappings that fulfills all of the above requirements. It is based on the notion of ${\mathcal{C}}$ -maximum recovery, for a query language ${\mathcal{C}}$ , a notion designed to generate inverse mappings that recover back only the information that can be retrieved with queries in ${\mathcal{C}}$ . By focusing on the language of conjunctive queries (CQ), we are able to find a mapping language that contains the class of st-tgds, is closed under CQ-maximum recovery, and for which the chase procedure can be used to exchange data efficiently. Furthermore, we show that our choices of inverse notion and mapping language are optimal, in the sense that choosing a more expressive inverse operator or mapping language causes the loss of these properties. 相似文献
12.
13.
Maria Buuales Maria Cristina Ballesteros-Briones Manuela Gonzalez-Aparicio Sandra Hervas-Stubbs Eva Martisova Uxua Mancheo Ana Ricobaraza Sara Lumbreras Cristian Smerdou Ruben Hernandez-Alcoceba 《International journal of molecular sciences》2021,22(8)
Immune checkpoint inhibitors (ICIs) have demonstrated remarkable efficacy in a growing number of malignancies. However, overcoming primary or secondary resistances is difficult due to pharmacokinetics issues and side effects associated with high systemic exposure. Local or regional expression of monoclonal antibodies (mAbs) using gene therapy vectors can alleviate this problem. In this work, we describe a high-capacity adenoviral vector (HCA-EFZP-aPDL1) equipped with a mifepristone-inducible system for the controlled expression of an anti-programmed death ligand 1 (PD-L1) blocking antibody. The vector was tested in an immune-competent mouse model of colorectal cancer based on implantation of MC38 cells. A single local administration of HCA-EFZP-aPDL1 in subcutaneous lesions led to a significant reduction in tumor growth with minimal release of the antibody in the circulation. When the vector was tested in a more stringent setting (rapidly progressing peritoneal carcinomatosis), the antitumor effect was marginal even in combination with other immune-stimulatory agents such as polyinosinic-polycytidylic acid (pI:C), blocking mAbs for T cell immunoglobulin, mucin-domain containing-3 (TIM-3) or agonistic mAbs for 4-1BB (CD137). In contrast, macrophage depletion by clodronate liposomes enhanced the efficacy of HCA-EFZP-aPDL1. These results highlight the importance of addressing macrophage-associated immunoregulatory mechanisms to overcome resistance to ICIs in the context of colorectal cancer. 相似文献
14.
Larisa Anghel Radu Sascu Ioana Mdlina Zota Cristian Sttescu 《International journal of molecular sciences》2021,22(11)
Non-ischemic dilated cardiomyopathy encompasses a wide spectrum of myocardial disorders, characterized by left ventricular dilatation with systolic impairment and increased risk of sudden cardiac death. In spite of all the therapeutic progress that has been made in recent years, dilated cardiomyopathy continues to be an important cause of cardiac transplant, being associated with an enormous cost burden for health care systems worldwide. Predicting the prognosis of patients with dilated cardiomyopathy is essential to individualize treatment. Late gadolinium enhancement-cardiac magnetic resonance imaging, microvolt T-wave alternans, and genetic testing have emerged as powerful tools in predicting sudden cardiac death occurrence and maximizing patient’s selection. Despite all these new diagnostic modalities, additional tests to complement or replace current tools are required for better risk stratification. Therefore, biomarkers are an easy and important tool that can help to detect patients at risk of adverse cardiovascular events. Additionally, identifying potential biomarkers involved in dilated cardiomyopathy can provide us important information regarding the diagnostic, prognostic, risk stratification, and response to treatment for these patients. Many potential biomarkers have been studied in patients with dilated cardiomyopathy, but only a few have been adopted in current practice. Therefore, the aim of our review is to provide the clinicians with an update on the well-known and novel biomarkers that can be useful for risk stratification of patients with non-ischemic dilated cardiomyopathy. 相似文献
15.
NH3-NO/NO2 SCR for diesel exhausts after treatment: mechanism and modelling of a catalytic converter
Nova Isabella Ciardelli Cristian Tronconi Enrico Chatterjee Daniel Weibel Michel 《Topics in Catalysis》2007,42(1-4):43-46
We review herein the key mechanistic and kinetic features of the reactions involved in the NH3-NO/NO2 SCR system investigated by dynamic reactive experiments over a V-based commercial powdered catalyst, eventually leading to
the proposal of an original redox scheme which accounts for stoichiometry, selectivity and intrinsic kinetics of the global
SCR process. 相似文献
16.
This paper describes an improved, equation oriented user friendly version of the modular computer package PROSYN—a mixed-integer nonlinear programming (MINLP) process synthesizer. A number of strategies are described and implemented for the outer approximation and equality relaxation algorithm (OA/ER) in order to reduce the undesirable effects of nonstructured nonconvexities in the master problem. These strategies include use of valid outer-approximations for splitters and mixers and various ways of handling the linearizations. An NLP initializer, model generator and a comprehensive library of models for basic process units and interconnection nodes, and a comprehensive library of basic physical properties have been developed and built in the PROSYN package. In this way PROSYN can be used to solve problems at different levels of complexity: from the simple NLP flowsheeting up to the MINLP synthesis through the modeling and decomposition (M/D) strategy and simultaneous heat integration including HEN costs. Applications with PROSYN are demonstrated with several example problems. 相似文献
17.
Daniela Fogli Loredana Parasiliti Provenza Cristian Bernareggi 《Universal Access in the Information Society》2014,13(2):205-226
Rich Internet applications have removed most of the constraints of Web 1.0 while giving users more responsiveness and advanced browsing and interaction experiences. These new horizons, however, raise many challenges for people with disabilities or using limited hardware and software technologies, whose risk to be excluded from the benefits deriving from advanced web applications. To address this problem, WCAG 2.0 guidelines have been released as the newest World Wide Web Consortium recommendation for accessible web content, and WAI-ARIA is a candidate recommendation which provides reference specifications for accessible rich Internet applications. However, both specifications contain a huge amount of information that often discourages most web designers from dealing with accessibility issues. Moreover, guidelines are suitable and usually adopted to judge a design solution a posteriori, but they do not suggest how to face a design problem constructively. This paper proposes a design pattern language for accessibility. The language can be regarded as a universal design resource for helping web designers create accessible rich Internet applications compliant with the most recent standards. Knowledge representation through design patterns reflects the problem-solving approach usually followed by software and web designers, while pattern organization in a structured language aims to guide web designers throughout the design process. The language has been implemented as an accessible rich Internet application itself, thus allowing designers with disabilities to participate in web design. In order to evaluate the design pattern language, a three-step process was carried out including: (1) a heuristic analysis with a group of human–computer interaction experts, (2) a survey study with a group of web designers, and (3) a validation on the field with two designers who have been requested to apply the language in real design cases. 相似文献
18.
Caroline Cagnin Bruno Matheus Simões Fábio Yamashita Gizilene Maria de Carvalho Maria Victória Eiras Grossmann 《Polymer Engineering and Science》2021,61(2):388-396
This work aims to develop hydrogel films of starch and carboxymethyl cellulose (CMC) crosslinked with sodium trimetaphosphate (STMP) and to characterize some of their properties. Starch and STMP (S/T), starch and CMC (S/C), and mixed (S/T/C) films were prepared by casting. The degree of substitution, morphology, swelling degree, FTIR, mechanical properties, and sorption isotherms were studied. Reticulated samples (S/T and S/T/C) showed the same degree of substitution (0.050 ± 0.001). All films presented homogeneous morphology, but the mixed film showed greater roughness. Crosslinking increased the swelling capacity of the mixed hydrogel at pH 7, although it remained decreased concerning the S/T hydrogel. However, this property was sensitive to pH variations. The mixed film (S/T/C) showed greater mechanical resistance. The casting process was efficient to produce hydrogel films of starch/CMC crosslinked with STMP and the general results demonstrated the advantages of the mixed hydrogel. 相似文献
19.
Cristian Molinaro Jan Chomicki Jerzy Marcinkowski 《Annals of Mathematics and Artificial Intelligence》2009,57(2):103-124
This paper addresses the problem of representing the set of repairs of a possibly inconsistent database by means of a disjunctive database. Specifically, the class of denial constraints is considered. We show that, given a database and a set of denial constraints, there exists a (unique) disjunctive database, called canonical, which represents the repairs of the database w.r.t. the constraints and is contained in any other disjunctive database with the same set of minimal models. We propose an algorithm for computing the canonical disjunctive database. Finally, we study the size of the canonical disjunctive database in the presence of functional dependencies for both subset-based repairs and cardinality-based repairs. 相似文献
20.
We introduce general sequences of linear operators obtained from classical approximation processes which are useful in the
approximation of the resolvent operators of the generators of suitable C
0-semigroups. The main aim is the representation of the resolvent operators in terms of classical approximation operators.
Work performed under the auspices of PRIN 2006–07 “Kolmogorov equations” (coordinator G. Da Prato) 相似文献