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141.
Daniela Heimler Pamela Vignolini Paola Arfaioli Laura Isolani Annalisa Romani 《Journal of the science of food and agriculture》2012,92(3):551-556
BACKGROUND: Lactuca sativa L. ssp. acephala L., cv. Batavia red Mohican plants were cultivated under intensive conventional, organic and biodynamic farming and were analyzed for their polyphenol content and antiradical activity in order to demonstrate the influence of farming on yield, polyphenol content and antiradical activity. RESULTS: The yield of plants from conventional farming was the highest (2.89 kg m?2), while polyphenol content, measured by spectrophotometry, of these plants was lower at P < 0.05 (1.36 mg g?1) than the content of plants from organic and biodynamic farming (1.74 and 1.85 mg g?1, respectively). The antiradical activity, measured by DPPH · assay, was positively correlated to flavonoid and hydroxycinnamic acid contents. CONCLUSION: Flavonoid, hydroxycinnamic acid and anthocyan patterns were not affected by the type of cultivation, while quantitative differences were demonstrated and some differences were found between conventional farming and organic or biodynamic farming. The yield of conventionally grown salads was the highest. Copyright © 2011 Society of Chemical Industry 相似文献
142.
The use of wireless mobile sensors is of great relevance for a number of strategic applications devoted to monitoring critical
areas where sensors can not be deployed manually. Mobile sensors can adapt their position on the basis of a local evaluation
of coverage, thus permitting an autonomous deployment. Several algorithms have been proposed to deploy mobile sensors over
an area of interest. The applicability of these approaches largely depends on a proper formalization of rigorous rules to
coordinate sensor movements, solve local conflicts and manage possible failures of communications and devices. In this paper
we introduce P&P, a communication protocol that permits a correct and efficient coordination of sensor movements in agreement
with the Push & Pull algorithm. We deeply investigate and solve the problems that may occur when coordinating asynchronous local decisions in
the presence of an unreliable transmission medium and possibly faulty devices such as in the typical working scenario of mobile
sensor networks. Simulation results show the performance of our protocol under a range of operative settings, including conflict
situations and irregularly shaped target areas. Furthermore, a performance comparison between the P&P protocol and one of
the best solutions based on the virtual force approach, shows the superiority of our proposal in terms of deployment time,
message exchanges and energy consumption. 相似文献
143.
Clare Dyer‐Smith Luke X. Reynolds Annalisa Bruno Donal D. C. Bradley Saif A. Haque Jenny Nelson 《Advanced functional materials》2010,20(16):2701-2708
In organic solar cells, high open circuit voltages may be obtained by choosing materials with a high offset between the donor highest occupied molecular orbital (HOMO) and acceptor lowest unoccupied molecular orbital (LUMO). However, increasing this energy offset can also lead to photophysical processes that compete with charge separation. In this paper the formation of triplet states is addressed in blends of polyfluorene polymers with a series of PCBM multi‐adducts. Specifically, it is demonstrated that the formation of such triplets occurs when the offset energy between donor ionization potential and acceptor electron affinity is ~1.6 eV or greater. Spectroscopic measurements support a mechanism of resonance energy transfer for triplet formation, influenced by the energy levels of the materials, but also demonstrate that the competition between processes at the donor–acceptor interface is strongly influenced by morphology. 相似文献
144.
Cristina Costa Annalisa Lucera Valentina Lacivita Maria Antonietta Saccotelli Amalia Conte Matteo Alessandro Del Nobile 《International Journal of Dairy Technology》2016,69(3):401-409
Different polymeric films and various headspace conditions (air, vacuum and four different modified atmosphere packaging) were combined to select a packaging system that assured the desired shelf life for two types of portioned Canestrato di Moliterno cheese ripened for 4 and 12 months. To evaluate the quality deterioration of the packaged cheese samples under refrigerated conditions, texture change, weight loss, water activity, moisture content, microbial contamination, pH and sensory attributes were monitored during storage. The results highlighted that a high‐barrier multilayer film delayed proliferation of moulds and gave the best results for both types of ripened cheese. 相似文献
145.
Carla Zannella Annalisa Chianese Luciana Palomba Maria Elena Marcocci Rosa Bellavita Francesco Merlino Paolo Grieco Veronica Folliero Anna De Filippis Marialuisa Mangoni Lucia Nencioni Gianluigi Franci Massimiliano Galdiero 《International journal of molecular sciences》2022,23(4)
The COVID-19 pandemic has evidenced the urgent need for the discovery of broad-spectrum antiviral therapies that could be deployed in the case of future emergence of novel viral threats, as well as to back up current therapeutic options in the case of drug resistance development. Most current antivirals are directed to inhibit specific viruses since these therapeutic molecules are designed to act on a specific viral target with the objective of interfering with a precise step in the replication cycle. Therefore, antimicrobial peptides (AMPs) have been identified as promising antiviral agents that could help to overcome this limitation and provide compounds able to act on more than a single viral family. We evaluated the antiviral activity of an amphibian peptide known for its strong antimicrobial activity against both Gram-positive and Gram-negative bacteria, namely Temporin L (TL). Previous studies have revealed that TL is endowed with widespread antimicrobial activity and possesses marked haemolytic activity. Therefore, we analyzed TL and a previously identified TL derivative (Pro3, DLeu9 TL, where glutamine at position 3 is replaced with proline, and the D-Leucine enantiomer is present at position 9) as well as its analogs, for their activity against a wide panel of viruses comprising enveloped, naked, DNA and RNA viruses. We report significant inhibition activity against herpesviruses, paramyxoviruses, influenza virus and coronaviruses, including SARS-CoV-2. Moreover, we further modified our best candidate by lipidation and demonstrated a highly reduced cytotoxicity with improved antiviral effect. Our results show a potent and selective antiviral activity of TL peptides, indicating that the novel lipidated temporin-based antiviral agents could prove to be useful additions to current drugs in combatting rising drug resistance and epidemic/pandemic emergencies. 相似文献
146.
Tiziana Schioppa Hoang Oanh Nguyen Valentina Salvi Norma Maugeri Fabrizio Facchinetti Gino Villetti Maurizio Civelli Carolina Gaudenzi Mauro Passari Francesca Sozio Ilaria Barbazza Nicola Tamassia Marco A. Cassatella Annalisa Del Prete Daniela Bosisio Laura Tiberio 《International journal of molecular sciences》2022,23(9)
Neutrophils, the most abundant subset of leukocytes in the blood, play a pivotal role in host response against invading pathogens. However, in respiratory diseases, excessive infiltration and activation of neutrophils can lead to tissue damage. Tanimilast-international non-proprietary name of CHF6001—is a novel inhaled phosphodiesterase 4 (PDE4) inhibitor in advanced clinical development for the treatment of chronic obstructive pulmonary disease (COPD), a chronic inflammatory lung disease where neutrophilic inflammation plays a key pathological role. Human neutrophils from healthy donors were exposed to pro-inflammatory stimuli in the presence or absence of tanimilast and budesonide—a typical inhaled corticosteroid drug-to investigate the modulation of effector functions including adherence to endothelial cells, granule protein exocytosis, release of extracellular DNA traps, cytokine secretion, and cell survival. Tanimilast significantly decreased neutrophil-endothelium adhesion, degranulation, extracellular DNA traps casting, and cytokine secretion. In contrast, it promoted neutrophil survival by decreasing both spontaneous apoptosis and cell death in the presence of pro-survival factors. The present work suggests that tanimilast can alleviate the severe tissue damage caused by massive recruitment and activation of neutrophils in inflammatory diseases such as COPD. 相似文献
147.
A probabilistic framework for multidisciplinary design: Application to the hydrostructural optimization of supercavitating hydrofoils
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Luca Bonfiglio Paris Perdikaris Jose del Águila George E. Karniadakis 《International journal for numerical methods in engineering》2018,116(4):246-269
The analysis and optimization of complex multiphysics systems presents a series of challenges that limit the practical use of computational tools. Specifically, the optimization of such systems involves multiple interconnected components with competing quantities of interest and high‐dimensional spaces and necessitates the use of costly high‐fidelity solvers to accurately simulate the coupled multiphysics. In this paper, we put forth a data‐driven framework to address these challenges leveraging recent advances in machine learning. We combine multifidelity Gaussian process regression and Bayesian optimization to construct probabilistic surrogate models for given quantities of interest and explore high‐dimensional design spaces in a cost‐effective manner. The synergistic use of these computational tools gives rise to a tractable and general framework for tackling realistic multidisciplinary optimization problems. To demonstrate the specific merits of our approach, we have chosen a challenging large‐scale application involving the hydrostructural optimization of three‐dimensional supercavitating hydrofoils. To this end, we have developed an automated workflow for performing multiresolution simulations of turbulent multiphase flows and multifidelity structural mechanics (combining three‐dimensional and one‐dimensional finite element results), the results of which drive our machine learning analysis in pursuit of the optimal hydrofoil shape. 相似文献
148.
Antonella Virgilio Annalisa Pecoraro Daniela Benigno Annapina Russo Giulia Russo Veronica Esposito Aldo Galeone 《International journal of molecular sciences》2022,23(11)
In this paper, we study the antiproliferative potential and the contribution of its loop residues in six different human cancer cell lines by preparing five T30923 variants using the single residue replacement approach of loop thymidine with an abasic site mimic (S). G-rich oligonucleotides (GRO) show interesting anticancer properties because of their capability to adopt G-quadruplex structures (G4s), such as the G4 HIV-1 integrase inhibitor T30923. Considering the multi-targeted effects of G4-aptamers and the limited number of cancer cell lines tested, particularly for T30923, it should be important to find a suitable tumor line, in addition to considering that the effects also strictly depend on G4s. CD, NMR and non-denaturating polyacrylamide gel electrophoresis data clearly show that all modified ODNs closely resemble the dimeric structure of parallel G4s’ parent aptamer, keeping the resistance in biological environments substantially unchanged, as shown by nuclease stability assay. The antiproliferative effects of T30923 and its variants are tried in vitro by MTT assays, showing interesting cytotoxic activity, depending on time and dose, for all G4s, especially in MDA-MB-231 cells with a reduction in cell viability approximately up to 30%. Among all derivatives, QS12 results are the most promising, showing more pronounced cytotoxic effects both in MDA-MB-231 and Hela cells, with a decrease in cell viability from 70% to 60%. In summary, the single loop residue S substitution approach may be useful for designing antiproliferative G4s, considering that most of them, characterized by single residue loops, may be able to bind different targets in several cancer cell pathways. Generally, this approach could be of benefit by revealing some minimal functional structures, stimulating further studies aimed at the development of novel anticancer drugs. T30923相似文献
149.
Annalisa Serio Clemencia Chaves-LópezMaria Martuscelli Giovanni MazzarrinoCarla Di Mattia Antonello Paparella 《LWT》2014
The antimicrobial activity of the hydro-alcohol extract of Myrtus communis L. (ME) berries was investigated against six Listeria monocytogenes strains (2 type strains and 4 isolates). Sub-lethal ME concentrations reduced L. monocytogenes counts by at least 2 log cycles. A Central Composite Design was used to investigate the combined effects of sub-lethal concentrations of ME (0.039–0.195 mL/100 mL), NaCl (0–2.0 g/100 mL) and pH (5.0–7.0) on strains growth. ME affected growth parameters, generally extending lag phase length and reducing maximum growth, sometimes with interactive effects with pH. The highest ME concentrations (0.117–0.195 mL/100 mL) combined with the lowest pH values (5.0–6.0) strongly reduced or even inhibited strains growth. 相似文献
150.
Annalisa Galeandro Angelo Doglioni Vincenzo Simeone 《Bulletin of Engineering Geology and the Environment》2017,76(2):587-600
Clayey soil strata, as all natural deposits, generally show variability in the values of their geotechnical properties. This is due mainly to geological and environmental processes such as deposition and diagenesis, which introduce heterogeneity, anisotropy and variability to soil properties. Other causes of variability, and thus uncertainty, are the representativeness of samples and errors related to testing procedure, measurement and data processing procedures. To improve our knowledge about the inherent variability in the geomechanical properties of clays, this work presents a case study related to the analysis of the strength variability along a log of marine stiff clay deposits, which are apparently quite homogeneous. The analysis was based on pocket penetrometer strength measurement, performed both punctually and across the whole deposit. The adopted testing procedure, which is fast and reliable, provides a really wide dataset of the investigated soil property, with more than 800 data points. These allow for detailed variability analysis, and a reliable estimation of the coefficient of variation as well as research into the best fitting probability density functions, which are key factors for robust design. The presented case study allows discussion of the inherent variability of soil properties, and its influence on the characteristic values of soil strength in geotechnical design. 相似文献