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81.
Giuseppe Ruvio Raffaele Solimene Antonietta D'Alterio Max J. Ammann Rocco Pierri 《国际射频与微波计算机辅助工程杂志》2013,23(5):598-609
A novel microwave breast cancer detection system consisting of an Evolutionary Global Optimized Vivaldi antenna and an algorithm inspired by MUltiple SIgnal Classification (MUSIC) is presented. Its performance is assessed by using a simplified numerical breast phantom for a number of critical conditions including the presence of fibroglandular tissues. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013. 相似文献
82.
Approaches for improving class cohesion identify refactoring opportunities using metrics that capture structural relationships between the methods of a class, e.g., attribute references. Semantic metrics, e.g., C3 metric, have also been proposed to measure class cohesion, as they seem to complement structural metrics. However, until now semantic relationships between methods have not been used to identify refactoring opportunities. In this paper we propose an Extract Class refactoring method based on graph theory that exploits structural and semantic relationships between methods. The empirical evaluation of the proposed approach highlighted the benefits provided by the combination of semantic and structural measures and the potential usefulness of the proposed method as a feature for software development environments. 相似文献
83.
Sandra Di Rocco David Eklund Chris Peterson Andrew J. Sommese 《Journal of Symbolic Computation》2011,46(1):23-33
Homotopy continuation provides a numerical tool for computing the equivalence of a smooth variety in an intersection product. Intersection theory provides a theoretical tool for relating the equivalence of a smooth variety in an intersection product to the degrees of the Chern classes of the variety. A combination of these tools leads to a numerical method for computing the degrees of Chern classes of smooth projective varieties in Pn. We illustrate the approach through several worked examples. 相似文献
84.
Recently, a number of inhibitors of the enzyme oxidosqualene cyclase (OSC; EC 5.4.99.7), a key enzyme in sterol biosynthesis,
were shown to inhibit in mammalian cells the multiplication of Trypanosoma cruzi, the parasite agent of Chagas’ disease. The gene coding for the OSC of T. cruzi has been cloned and expressed in Saccharomyces cerevisiae. The expression in yeast cells could be a safe and easy model for studying the activity and the selectivity of the potential
inhibitors of T. cruzi OSC. Using a homogenate of S. cerevisiae cells expressing T. cruzi OSC, we have tested 19 inhibitors: aza, methylidene, vinyl sulfide, and conjugated vinyl sulfide derivatives of oxidosqualene
and squalene, selected as representative of different classes of substrate analog inhibitors of OSC. The IC50 values of inhibition (the compound concentration at which the enzyme is inhibited by 50%) are compared with the values obtained
using OSC of pig liver and S. cerevisiae. Many inhibitors of pig liver and S. cerevisiae OSC show comparable IC50 for T. cruzi OSC, but some phenylthiovinyl derivatives are 10–100 times more effective on the T. cruzi enzyme than on the pig or S. cerevisiae enzymes. The expression of proteins of pathogenic organisms in yeast seems very promising for preliminary screening of compounds
that have potential therapeutic activity. 相似文献
85.
New iodoacetamide derivatives, containing a dodecyl or a squalenyl moiety, were synthesized. The effect of these new thiol-reacting
molecules was studied on two mutants of Alicyclobacillus acidocaldarius squalene-hopene cyclase constructed especially for this purpose. In the quintuple mutant, all five cysteine residues of the
enzyme are substituted with serine; in the sextuple mutant, this quintuple substitution is accompanied by the substitution
of aspartate D376, located at the enzyme’s active site, with a cysteine. N-Dodecyliodoacetamide had little activity toward either mutant, whereas N-squalenyliodoacetamide showed a stronger effect on the sextuple than on the quintuple mutant, as expected. 相似文献
86.
Fabiana Mallone Roberta Costi Marco Marenco Rocco Plateroti Antonio Minni Giuseppe Attanasio Marco Artico Alessandro Lambiase 《International journal of molecular sciences》2021,22(21)
Ocular fibrosis leads to severe visual impairment and blindness worldwide, being a major area of unmet need in ophthalmology and medicine. To date, the only available treatments are antimetabolite drugs that have significant potentially blinding side effects, such as tissue damage and infection. There is thus an urgent need to identify novel targets to prevent/treat scarring and postsurgical fibrosis in the eye. In this review, the latest progress in biological mechanisms underlying ocular fibrosis are discussed. We also summarize the current knowledge on preclinical studies based on viral and non-viral gene therapy, as well as chemical inhibitors, for targeting TGFβ or downstream effectors in fibrotic disorders of the eye. Moreover, the role of angiogenetic and biomechanical factors in ocular fibrosis is discussed, focusing on related preclinical treatment approaches. Moreover, we describe available evidence on clinical studies investigating the use of therapies targeting TGFβ-dependent pathways, angiogenetic factors, and biomechanical factors, alone or in combination with other strategies, in ocular tissue fibrosis. Finally, the recent progress in cell-based therapies for treating fibrotic eye disorders is discussed. The increasing knowledge of these disorders in the eye and the promising results from testing of novel targeted therapies could offer viable perspectives for translation into clinical use. 相似文献
87.
Rocco V. Dell’Aquila Giampiero Campa Marcello R. Napolitano Marco Mammarella 《Journal of Real-Time Image Processing》2007,1(3):213-224
This paper describes the design of a Real Time Machine-Vision (MV) Position Sensing System for the problem of Semi-Autonomous Docking within Aerial Refueling (AR) for Unmanned Aerial Vehicles (UAVs). In this effort, techniques and algorithms have been developed and extensively tested in the MATLAB/Simulink® Soft Real-Time environment as well as in Linux/RTAI Hard Real-Time environment. The overall MV software performs several tasks, such as the image acquisition from a real camera, the Feature Extraction (FE) from the acquired image, the Detection and Labeling (DAL) of the features, and the tanker-UAV Pose Estimation (PE). A Cyclic Asynchronous Buffer (CAB) mechanism was implemented for inter-process communication among Real Time and Non Real Time processes. The entire sensing system was tested using an 800 MHz PC-104 computer. The results confirmed the feasibility of executing image processing algorithms in real-time using off-the-shelf commercial hardware to obtain reliable relative position and orientation estimations. 相似文献
88.
Describes the results of research on the oscillatory behavior that has been systematically experienced in the force measured during contact motion of an industrial robot. Two phenomena have been found to be mainly responsible for it, namely, the arm structural elasticity due to the torsional flexibility of the joints and the torque ripple of the brushless motors. The structural elasticity is characterized by a resonance frequency which varies with the arm configuration, while the torque ripple has harmonics of frequency proportional to the motor velocity. Most severe oscillations, and even loss of the contact, arise when the resonance and ripple frequency values come closer or match, so that elasticity and ripple excite each other 相似文献
89.
Photochemical degradation of crude oil: Comparison between direct irradiation, photocatalysis, and photocatalysis on zeolite 总被引:3,自引:0,他引:3
Direct irradiation for 100h of crude oil from Basilicata (Southern Italy) gave in the case of linear and branched alkanes a reduction of 9 and 5%, respectively. On the contrary, cyclic alkanes decreased for 54% while aromatic hydrocarbons showed a reduction of 37%. These results are in agreement with a prevalent electron transfer mechanism. Photocatalysis (100h) gave extensive degradation of crude oil: linear alkanes were degraded for 98.66%, branched alkanes were reduced for 97.31%, cyclic alkanes for 96.04%, while aromatic compounds and alkenes were reduced for 99.54 and 98.38%, respectively. These results are in agreement with a prevalent hydrogen abstraction mechanism. When photocatalysis is performed in the presence of zeolite linear alkanes were degraded for 79.85%, branched alkanes were reduced for 45.38%, cyclic alkanes for 58.10%, while aromatic compounds were reduced for 91.85%. In this case, an increase of the relative amount of alkenes (42.05%) was observed. 相似文献
90.
The irradiation of four Italian white wines with a visible light comparable to that encountered in the market place showed a modification in the amount of aliphatic esters in the wines. Aliphatic esters are responsible for fruity aromas in wines. The first wine studied was the Gewürztraminer, a white wine from Alto Adige (Northern Italy). The amounts of the esters presents in the wine decreased. All the curves follow a pseudo-first-order kinetics. This behaviour can be explained assuming a photooxidation process catalysed by riboflavin. When Arneis Blangè was irradiated, ethyl acetate showed an increase after one day of irradiation; its content then decreased and after five days' irradiation its concentration reached a maximum. Conversely, the concentration of other aliphatic esters decreased after one day's irradiation and then increased progressively to reach a maximum after five days' irradiation. The same behaviour was observed with Pecorino wine. In this case, the concentration of the aliphatic esters decreased until the second day of irradiation but increased after five days' irradiation. In the case of the irradiation of Lighea Zibibbo all the esters showed an increase in concentration after one day of irradiation. The concentration decreased after two days' irradiation, and then increased to reach a maximum after seven days of irradiation. The increase in the amount of esters in some wines and, by contrast, the decrease in the same compounds in Gewürztraminer can be explained by considering that, during the irradiation, the pH of Gewürztraminer did not change, while the pH of Arneis Blangè changed following a curve similar to that showed by the concentration of esters. The pH change can be explained assuming the presence of a photocatalytic process induced by the presence of metals in the wines and influencing the amount of tartaric acid. 相似文献