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1.
Massimiliano Corsini Elisa Drelie Gelasca Touradj Ebrahimi Mauro Barni 《Multimedia, IEEE Transactions on》2007,9(2):247-256
This paper addresses the problem of assessing distortions produced by watermarking 3D meshes. In particular, a new methodology for subjective evaluation of the quality of 3D objects is proposed and implemented. Two objective metrics derived from measures of surface roughness are then proposed and their efficiency to predict the perceptual impact of 3D watermarking is assessed and compared with the state of the art. Results obtained show good correlations between the proposed objective metrics and subjective assessments by human observers 相似文献
2.
Emilio Marengo Valentina Longo Elisa Robotti Marco Bobba Fabio Gosetti Orfeo Zerbinati Silvana Di Martino 《应用聚合物科学杂志》2008,109(6):3975-3982
Principal component regression (PCR), partial least squares (PLS), StepWise ordinary least squares regression (OLS), and back‐propagation artificial neural network (BP‐ANN) are applied here for the determination of the propylene concentration of a set of 83 production samples of ethylene–propylene copolymers from their infrared spectra. The set of available samples was split into (a) a training set, for models calculation; (b) a test set, for selecting the correct number of latent variables in PCR and PLS and the end point of the training phase of BP‐ANN; (c) a production set, for evaluating the predictive ability of the models. The predictive ability of the models is thus evaluated by genuine predictions. The model obtained by StepWise OLS turned out to be the best one, both in fitting and prediction. The study of the breakdown number of samples to be included in the training set showed that at least 52 experiments are necessary to build a reliable and predictive calibration model. It can be concluded that FTIR spectroscopy and OLS can be properly employed for monitoring the synthesis or the final product of ethylene–propylene copolymers, by predicting the concentration of propylene directly along the process line. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
3.
4.
Lorena Cuenca-Bermejo Elisa Pizzichini Valeria C. Gonalves María Guilln-Díaz Elena Aguilar-Moino Consuelo Snchez-Rodrigo Ana-María Gonzlez-Cuello Emiliano Fernndez-Villalba María Trinidad Herrero 《International journal of molecular sciences》2021,22(9)
The diurnal rodent Octodon degus (O. degus) is considered an attractive natural model for Alzheimer’s disease and other human age-related features. However, it has not been explored so far if the O. degus could be used as a model to study Parkinson’s disease. To test this idea, 10 adult male O. degus were divided into control group and MPTP-intoxicated animals. Motor condition and cognition were examined. Dopaminergic degeneration was studied in the ventral mesencephalon and in the striatum. Neuroinflammation was also evaluated in the ventral mesencephalon, in the striatum and in the dorsal hippocampus. MPTP animals showed significant alterations in motor activity and in visuospatial memory. Postmortem analysis revealed a significant decrease in the number of dopaminergic neurons in the ventral mesencephalon of MPTP animals, although no differences were found in their striatal terminals. We observed a significant increase in neuroinflammatory responses in the mesencephalon, in the striatum and in the hippocampus of MPTP-intoxicated animals. Additionally, changes in the subcellular expression of the calcium-binding protein S100β were found in the astrocytes in the nigrostriatal pathway. These findings prove for the first time that O. degus are sensitive to MPTP intoxication and, therefore, is a suitable model for experimental Parkinsonism in the context of aging. 相似文献
5.
Alberto Doretto Francesca Bona Elisa Falasco Daniele Morandini Elena Piano Stefano Fenoglio 《河流研究与利用》2020,36(1):91-101
Droughts are affecting an increasing number of lotic ecosystems worldwide due to the combined effects of climatic and anthropogenic pressures. Unlike naturally intermittent rivers, where the drying phase is a part of the annual flow regime, water scarcity in Alpine rivers represents a relatively recent phenomenon and, therefore, a major threat for the biodiversity of these lotic ecosystems. However, Alpine stream community response to drought is still poorly investigated. Here, we assess the recovery of macroinvertebrates in two Alpine streams after a supraseasonal drought. As water returned, a total of 10 sampling sessions were carried out, and temporal patterns in diversity, density, and taxonomic composition of benthic communities, as well as in the percentage of functional feeding groups, were investigated. We found that the resistance of invertebrate communities in Alpine streams is generally low: drought markedly reduced the diversity and density of macroinvertebrates. Conversely, our results suggest that the passive dispersal by drift from the upstream river sections seems the most probable mechanism promoting the post‐drought recovery. Nevertheless, this resilience ability appears to be stream specific and influenced by intrinsic stream characteristics, including the flow permanence and distance from the nearest upstream perennial reach. This work sheds light on the ecological consequences of droughts on macroinvertebrate communities. As flow intermittency in Alpine areas is expected to intensify under current global change scenarios, results of this study provide important information to predict changes in the taxonomic composition and diversity of macroinvertebrate communities. 相似文献
6.
Elisa Bertino Giovanna Guerrini Marco Mesiti 《Journal of Intelligent Information Systems》2008,30(1):55-92
Measuring the structural similarity between an XML document and a DTD has many relevant applications that range from document
classification and approximate structural queries on XML documents to selective dissemination of XML documents and document
protection. The problem is harder than measuring structural similarity among documents, because a DTD can be considered as
a generator of documents. Thus, the problem is to evaluate the similarity between a document and a set of documents. An effective
structural similarity measure should face different requirements that range from considering the presence and absence of required
elements, as well as the structure and level of the missing and extra elements to vocabulary discrepancies due to the use
of synonymous or syntactically similar tags. In the paper, starting from these requirements, we provide a definition of the
measure and present an algorithm for matching a document against a DTD to obtain their structural similarity. Finally, experimental
results to assess the effectiveness of the approach are presented. 相似文献
7.
Dan Lin Prathima Rao Elisa Bertino Ninghui Li Jorge Lobo 《International Journal of Information Security》2010,9(4):253-273
Policy integration and inter-operation is often a crucial requirement when parties with different access control policies
need to participate in collaborative applications and coalitions. Such requirement is even more difficult to address for dynamic
large-scale collaborations, in which the number of access control policies to analyze and compare can be quite large. An important
step in policy integration and inter-operation is to analyze the similarity of policies. Policy similarity can sometimes also
be a pre-condition for establishing a collaboration, in that a party may enter a collaboration with another party only if
the policies enforced by the other party match or are very close to its own policies. Existing approaches to the problem of
analyzing and comparing access control policies are very limited, in that they only deal with some special cases. By recognizing
that a suitable approach to the policy analysis and comparison requires combining different approaches, we propose in this
paper a comprehensive environment—EXAM. The environment supports various types of analysis query, which we categorize in the
paper. A key component of such environment, on which we focus in the paper, is the policy analyzer able to perform several
types of analysis. Specifically, our policy analyzer combines the advantages of existing MTBDD-based and SAT-solver-based
techniques. Our experimental results, also reported in the paper, demonstrate the efficiency of our analyzer. 相似文献
8.
This paper presents a model for privacy preserving access control which is based on variety of purposes. Conditional purpose is applied along with allowed purpose and prohibited purpose in the model. It allows users using some data for certain purpose with conditions. The structure of conditional purpose-based access control model is defined and investigated through dynamic roles. Access purpose is verified in a dynamic behavior, based on subject attributes, context attributes and authorization policies. Intended purposes are dynamically associated with the requested data object during the access decision. An algorithm is developed to achieve the compliance computation between access purposes and intended purposes and is illustrated with Role-based access control (RBAC) in a dynamic manner to support conditional purpose-based access control. According to this model, more information from data providers can be extracted while at the same time assuring privacy that maximizes the usability of consumers’ data. It extends traditional access control models to a further coverage of privacy preserving in data mining atmosphere. The structure helps enterprises to circulate clear privacy promise, to collect and manage user preferences and consent. 相似文献
9.
Engineer Bainomugisha Jorge Vallejos Elisa Gonzalez Boix Pascal Costanza Theo D'Hondt Wolfgang De Meuter 《Software》2012,42(3):331-356
The iPhone SDK provides a powerful platform for the development of applications that make use of iPhone capabilities, such as sensors, GPS, Wi‐Fi, or Bluetooth connectivity. We observe that so far the development of iPhone applications has mostly been restricted to using Objective‐C. However, developing applications in plain Objective‐C on the iPhone OS suffers from limitations, such as the need for explicit memory management and lack of syntactic extension mechanism. Moreover, when developing distributed applications in Objective‐C, programmers have to manually deal with distribution concerns, such as service discovery, remote communication, and failure handling. In this paper, we discuss our experience in porting the Scheme programming language to the iPhone OS and how it can be used together with Objective‐C to develop iPhone applications. To support the interaction between Scheme programs and the underlying iPhone APIs, we have implemented a language symbiosis layer that enables programmers to access the iPhone SDK libraries from Scheme. In addition, we have designed high‐level distribution constructs to ease the development of distributed iPhone applications in an event‐driven style. We validate and discuss these constructs with a series of examples, including an iPod controller, a maps application, and a distributed multiplayer Scrabble‐like game. We discuss the lessons learned from this experience for other programming language ports to mobile platforms. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
10.
María Cabello-Donayre Lina M. Orrego Elisa Herrez Raquel García-Hernndez Jos M. Prez-Victoria 《International journal of molecular sciences》2022,23(18)
The protozoan parasite Leishmania, responsible for leishmaniasis, is one of the few aerobic organisms that cannot synthesize the essential molecule heme. Therefore, it has developed specialized pathways to scavenge it from its host. In recent years, some proteins involved in the import of heme, such as LHR1 and LFLVCRB, have been identified, but relevant aspects regarding the process remain unknown. Here, we characterized the kinetics of the uptake of the heme analogue Zn(II) Mesoporphyrin IX (ZnMP) in Leishmania major promastigotes as a model of a parasite causing cutaneous leishmaniasis with special focus on the force that drives the process. We found that ZnMP uptake is an active, inducible, and pH-dependent process that does not require a plasma membrane proton gradient but requires the presence of the monovalent cations Na+ and/or K+. In addition, we demonstrated that this parasite can efflux this porphyrin against a concentration gradient. We also found that ZnMP uptake differs among different dermotropic or viscerotropic Leishmania species and does not correlate with LHR1 or LFLVCRB expression levels. Finally, we showed that these transporters have only partially overlapping functions. Altogether, these findings contribute to a deeper understanding of an important process in the biology of this parasite. 相似文献