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排序方式: 共有3167条查询结果,搜索用时 15 毫秒
961.
Giuseppe Esposito Marcella Pesce Luisa Seguella Jie Lu Chiara Corpetti Alessandro Del Re Fatima Domenica Elisa De Palma Giovanni Esposito Walter Sanseverino Giovanni Sarnelli 《International journal of molecular sciences》2021,22(6)
Palmitoylethanolamide (PEA) is an N-acylethanolamide produced on-demand by the enzyme N-acylphosphatidylethanolamine-preferring phospholipase D (NAPE-PLD). Being a key member of the larger family of bioactive autacoid local injury antagonist amides (ALIAmides), PEA significantly improves the clinical and histopathological stigmata in models of ulcerative colitis (UC). Despite its safety profile, high PEA doses are required in vivo to exert its therapeutic activity; therefore, PEA has been tested only in animals or human biopsy samples, to date. To overcome these limitations, we developed an NAPE-PLD-expressing Lactobacillus paracasei F19 (pNAPE-LP), able to produce PEA under the boost of ultra-low palmitate supply, and investigated its therapeutic potential in a murine model of UC. The coadministration of pNAPE-LP and palmitate led to a time-dependent release of PEA, resulting in a significant amelioration of the clinical and histological damage score, with a significantly reduced neutrophil infiltration, lower expression and release of pro-inflammatory cytokines and oxidative stress markers, and a markedly improved epithelial barrier integrity. We concluded that pNAPE-LP with ultra-low palmitate supply stands as a new method to increase the in situ intestinal delivery of PEA and as a new therapeutic able of controlling intestinal inflammation in inflammatory bowel disease. 相似文献
962.
Marilena Pariano Stefania Pieroni Antonella De Luca Rossana G. Iannitti Monica Borghi Matteo Puccetti Stefano Giovagnoli Giorgia Renga Fiorella DOnofrio Marina M. Bellet Claudia Stincardini Maria Agnese Della-Fazia Giuseppe Servillo Frank L. van de Veerdonk Claudio Costantini Luigina Romani 《International journal of molecular sciences》2021,22(12)
963.
Further Results to Time-Dependent Local Scour at Bridge Elements 总被引:2,自引:0,他引:2
This research intends to clarify the limitations of a local scour equation recently proposed, based on extended laboratory data collected at VAW, Zurich, Switzerland. The present project is concerned with four items: (1) clarification of the minimum laboratory dimensions required to apply Froude similitude; (2) effect of sloping abutments on scour advance; (3) extension of scour formula to spur dikes; and (4) effect of unsteady flow on scour development. These items were investigated mainly from an experimental point of view based on some 150 laboratory experiments and accounted for by a hydraulic approach. It was found that the basic scour equation mentioned may be applied provided additional limitations are specified. These are discussed in the light of the densimetric particle Froude number, the threshold Froude number, and other important parameters that influence the progress of local scour. The results of this study may be applied to practice, provided the limitations of the computational approach are respected. 相似文献
964.
Progressive crushing of fiber-reinforced composite structural components of a Formula One racing car
Chiara Bisagni Giuseppe Di Pietro Lara Fraschini Davide Terletti 《Composite Structures》2005,68(4):491-503
The present paper describes an experimental and numerical investigation on energy absorbers for Formula One side impact and steering column impact. The crash tests are performed measuring the load-shortening diagram and the energy absorbed by the structure. A finite element model is then developed using the non-linear, explicit dynamic code LS-DYNA. To set up the numerical model, tubes crushing testing are conducted to determine the material failure modes and to characterise them with LS-DYNA. The results presented in this study show that the composite structural components of the investigated Formula One racing car possess high value of specific absorbed energy and crash load efficiency around 1.1. The finite element simulations accurately predict the overall shape, magnitude and pulse duration in all the types of impact as well as the deformation and failure of the structures. Comparing the numerical data of the specific absorbed energy to the experimental results, the differences are around 10%. 相似文献
965.
Giuseppe Grassi Luigi A. Grieco 《International Journal of Circuit Theory and Applications》2005,33(1):53-64
This paper presents a new CNN‐based architecture for real‐time video coding applications. The proposed approach, by exploiting object‐oriented CNN algorithms and MPEG encoding capabilities, enables low bit‐rate encoder/decoder to be designed. Simulation results using Claire video sequence show the effectiveness of the proposed scheme. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
966.
Gennaro Costagliola Vincenzo Deufemia Giuseppe Polese 《Electronic Notes in Theoretical Computer Science》2005,127(4):107
Editors for visual languages should provide a user-friendly environment supporting end users in the composition of visual sentences in an effective way. Syntax-aware editors are a class of editors that prompt users into writing syntactically correct programs by exploiting information on the visual language syntax. In particular, they do not constrain users to enter only correct syntactic states in a visual sentence. They merely inform the user when visual objects are syntactically correct. This means detecting both syntax and potential semantic errors as early as possible and providing feedback on such errors in a non-intrusive way during editing. As a consequence, error handling strategies are an essential part of such editing style of visual sentences.In this work, we develop a strategy for the construction of syntax-aware visual language editors by integrating incremental subsentence parsers into free-hand editors. The parser combines the LR-based techniques for parsing visual languages with the more general incremental Generalized LR parsing techniques developed for string languages. Such approach has been profitably exploited for introducing a noncorrecting error recovery strategy, and for prompting during the editing the continuation of what the user is drawing. 相似文献
967.
Penousal Machado Juan Romero Amílcar Cardoso Antonino Santos 《New Generation Computing》2005,23(2):143-155
User fatigue is probably the most pressing problem in current Interactive Evolutionary Computation systems. To address it
we propose the use of automatic seeding procedure, phenotype filters, and partial automation fitness assignment. We test this
approaches in the visual arts domain. To further enhance interactive evolution applications in aesthetic domains, we propose
the use of artificial art critics—systems that perform stylistic and aesthetic valuations of art—presenting experimental results.
Penousal Machado: He is a researcher at Centre for Informatics and Systems of the University of Coimbra (CISUC). He is the author of more than
20 journals and conference papers, and chair of several international workshops. His main research interest is the study and
development of evolutionary approaches to creativity and artificial art.
Juan Romero, Ph.D.: He is the founder of the “Creative Computer Group” of the RNASA Lab. His present research focuses on (i) Hybrid Society,
which consists of an egalitarian society composed of creative computers and human beings (ii) Artificial Art, using artificial
art critics and creators based on connectionist and evolutionary techniques.
Amílcar Cardoso, Ph.D.: He is an Associate Professor at the Department of Informatics Engineering of the University of Coimbra. He is the leader
of the CISUC AILab, and founder of the Creative Systems Group. His main research interest is the study and implementation
of computer models of creativity. He has background as professional musician and composer.
Antonino Santos, Ph.D.: He is the author/editor of more than 25 articles and 7 books. He participated as researcher in 7 funded research proposals
concerning to Artificial Intelligence, Neural Networks and Internet Security. His present research focuses in hybrid systems,
creative systems, computer security, artificial neural networks and evolutionary computation. 相似文献
968.
An algebraic multigrid method (AMG) for solving convection-diffusion optimality systems is presented. Results of numerical experiments demonstrate robustness of the AMG scheme with respect to changes of the weight of the cost of the control and show that the computational performance of the proposed AMG scheme is comparable to that of AMG applied to single scalar equations. 相似文献
969.
The increasing interest for lightweight and portable electronic systems, cellphones and small digital devices is driving technological research towards integrated regenerating power sources with small dimensions and great autonomy. Conventional batteries are already unable to deliver power in ever smaller volumes while maintaining the requirements of long duration and light weight. A possible solution to overcome these limits is the use of miniaturized fuel cells. The fuel cell offers a greater gravimetric energy density compared to conventional batteries. The micromachining technology of silicon is an important tool to reduce the fuel cell structure to micron sizes. The use of silicon also gives the opportunity to integrate the power source and the electronic circuits controlling the fuel cell on the same structure. This article reports preliminary results concerning the micromachining process for fabricating a silicon-based electrocatalytic membrane for miniaturized Si-based proton-exchange membrane (PEM) fuel cells. 相似文献
970.
Procedure for calibrating an ultrasonic sensor for online monitoring of conversion in latex reactors
In order to estimate online conversion and polymer composition through sound velocity measurements, a mathematical model for calculating sound velocity in emulsion polymerization has been developed. With respect to previous modeling approaches, its main features are as follows: (1) the application to three‐phase, reacting systems of Urick equation (usually adopted for estimating sound velocity in multiphase, dispersed, unreacting systems, such as emulsions and suspensions); and (2) the development of an empirical relationship for estimating particle compressibility as a function of conversion during the reaction. The model has been validated through several sets of experimental data of batch and semibatch homo‐ and copolymerizations involving styrene, butyl acrylate, vinyl acetate, and methyl methacrylate. In most of the examined cases, the performances of the calibration model are satisfactory. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1451–1477, 1999 相似文献