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81.
Interoperability is a property referring to the ability of systems and organizations to work together. Today interoperability is recognized as a key step in the shift from isolated digital libraries toward a common information space that will allow users to browse through different digital libraries within a single integrated environment. In this paper, we discuss the premises underlying a novel Policy and Quality Interoperability Framework, taking into account the preliminary outcomes and the recommendations of the Policy and Quality Working Groups that are currently being run by the EU co-funded project Digital Library Interoperability, Best Practices, and Modeling Foundations (DL.org). 相似文献
82.
Perozziello G La Rocca R Cojoc G Liberale C Malara N Simone G Candeloro P Anichini A Tirinato L Gentile F Coluccio ML Carbone E Di Fabrizio E 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(18):2886-2894
This study aims to adoptively reduce the major histocompatibility complex class I (MHC-I) molecule surface expression of cancer cells by exposure to microfluid shear stress and a monoclonal antibody. A microfluidic system is developed and tumor cells are injected at different flow rates. The bottom surface of the microfluidic system is biofunctionalized with antibodies (W6/32) specific for the MHC-I molecules with a simple method based on microfluidic protocols. The antibodies promote binding between the bottom surface and the MHC-I molecules on the tumor cell membrane. The cells are injected at an optimized flow rate, then roll on the bottom surface and are subjected to shear stress. The stress is localized and enhanced on the part of the membrane where MHC-I proteins are expressed, since they stick to the antibodies of the system. The localized stress allows a stripping effect and consequent reduction of the MHC-I expression. It is shown that it is possible to specifically treat and recover eukaryotic cells without damaging the biological samples. MHC-I molecule expression on treated and control cell surfaces is measured on tumor and healthy cells. After the cell rolling treatment a clear reduction of MHC-I levels on the tumor cell membrane is observed, whereas no changes are observed on healthy cells (monocytes). The MHC-I reduction is investigated and the possibility that the developed system could induce a loss of these molecules from the tumor cell surface is addressed. The percentage of living tumor cells (viability) that remain after the treatment is measured. The changes induced by the microfluidic system are analyzed by fluorescence-activated cell sorting and confocal microscopy. Cytotoxicity tests show a relevant increased susceptibility of natural killer (NK) cells on microchip-treated tumor cells. 相似文献
83.
Alessandro Pezzella Luigia Capelli Aniello Costantini Giuseppina Luciani Fabiana Tescione Brigida Silvestri Giuseppe Vitiello Francesco Branda 《Materials science & engineering. C, Materials for biological applications》2013,33(1):347-355
A large number of recent literature data focus on modification/modulation of surface chemistry of inorganic materials in order to improve their functional properties. Melanins, a wide class of natural pigments, are recently emerging as a powerful organic component for developing bioinspired active material for a large number of applications from organoelectronics to bioactive compounds.Here we report the use of the approach referred as “chimie douce”, involving in situ formation of the hybrids through reactions of precursors under mild conditions, to prepare novel hybrid functional architectures based on eumelanin like 5,6 dihydroxyindole-2-carboxylic acid (DHICA) polymer and TiO2. Two synthesis procedures were carried out to get DHICA-melanin coated TiO2 nanoparticles as well as mixed DHICA/TiO2 hybrid nanostructures. Such systems were characterized through EPR, FT-IR and fluorescence spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), and TEM microscopy in order to assess the effect of synthesis path as well as of DHICA content on structural, morphological and optical properties of TiO2 nanostructures. In particular, EPR, FT-IR spectra and TGA analysis confirmed the presence of DHICA-melanin in these samples. TEM measurements indicated the formation of the nanoparticles having relatively narrow size distribution with average particle size of about 10 nm. DHICA-melanin does act as a morphological agent affecting morphology of hybrid nanostructures. XRD analysis proved that TiO2 hybrid nanoparticles kept anatase structures for DHICA-melanin contents within the range of investigated compositions, i.e. up to 50% wt/wt. 相似文献
84.
Bella Federico Muñoz-García Ana B. Meligrana Giuseppina Lamberti Andrea Destro Matteo Pavone Michele Gerbaldi Claudio 《Nano Research》2017,10(8):2891-2903
Due to their inherent safety,low cost,and structural stability,TiO2 nanostructures represent a suitable choice as anode materials in sodium-ion batteries.In the recent years,various hypotheses have been proposed regarding the actual mechanism of the reversible insertion of sodium ions in the TiO2 structure,and previous reports are often controversial in this respect.Interestingly,when tested as binder-and conducting additive-free electrodes in laboratory-scale sodium cells,amorphous and crystalline (anatase) TiO2 nanotubular arrays obtained by simple anodic oxidation exhibit peculiar and intrinsically different electrochemical responses.In particular,after the initial electrochemical activation,anatase TiO2 shows excellent rate capability and very stable long-term cycling performance with larger specific capacities,and thus a clearly superior response compared with the amorphous counterpart.To obtain deeper insight,the present materials are thoroughly characterized by scanning electron microscopy and ex situ X-ray diffraction,and the insertion of sodium ions in the TiO2 bulk phases is systematically modeled by density functional theory calculations.The present results may contribute to the development of more systematic screening approaches to identify suitable active materials for highly efficient sodium-based energy storage systems. 相似文献
85.
Elisa Sartini Giuseppina P. Parpinello Sergio Galassi 《International Journal of Food Properties》2013,16(5):1081-1089
This research represents a first attempt to chemically characterize wines produced from the autochthonous grape variety, Uva Longanesi, based upon the phenolic compounds responsible for its high astringency as confirmed by preliminary sensory analysis. In addition, a wine produced from Sangiovese, the most popular grape variety in the Emilia-Romagna region, was analyzed for comparative purposes. Results showed that Uva Longanesi wine had a higher pH, alcohol concentration, and total dry extract than the Sangiovese wine. With regards to phenolic constituents, the Uva Longanesi wine had higher color parameters and greater concentrations of total phenolics, including monomeric anthocyanins, small polymeric pigments, and tannins. The phenolic composition of Uva Longanesi wine was found to be responsible for the high reactivity of the wine during fining trials. 相似文献
86.
Abstract The large-scale deployment of wide-area monitoring systems could play a strategic role in supporting the evolution of traditional power systems toward smarter and self-healing grids. The correct operation of these synchronized monitoring systems requires a common and accurate timing reference usually provided by a satellite-based global positioning system. Although these satellites signals provide timing accuracy that easily exceeds the needs of the power industry, they are extremely vulnerable to radio frequency interference. Consequently, a comprehensive analysis aimed at identifying their potential vulnerabilities is of paramount importance for correct and safe wide-area monitoring system operation. Armed with such a vision, this article presents and discusses the results of an experimental analysis aimed at characterizing the vulnerability of global positioning system based wide-area monitoring systems to external interferences. The article outlines the potential strategies that could be adopted to protect global positioning system receivers from external cyber-attacks and proposes decentralized defense strategies based on self-organizing sensor networks aimed at assuring correct time synchronization in the presence of external attacks. 相似文献
87.
Daria Brambilla Cesare Mancuso Mariagrazia Rita Scuderi Paolo Bosco Giuseppina Cantarella Laurence Lempereur Giulia Di Benedetto Salvatore Pezzino Renato Bernardini 《Nutrition journal》2008,7(1):29
This review will discuss some issues related to the risk/benefit profile of the use of dietary antioxidants. Thus, recent
progress regarding the potential benefit of dietary antioxidants in the treatment of chronic diseases with a special focus
on immune system and neurodegenerative disorders will be discussed here. It is well established that reactive oxygen species
(ROS) play an important role in the etiology of numerous diseases, such as atherosclerosis, diabetes and cancer. Among the
physiological defense system of the cell, the relevance of antioxidant molecules, such as glutathione and vitamins is quite
well established. Recently, the interest of researchers has, for example, been conveyed on antioxidant enzyme systems, such
as the heme oxygenase/biliverdin reductase system, which appears modulated by dietary antioxidant molecules, including polyphenols
and beta-carotene. These systems possibly counteract oxidative damage very efficiently and finally modulate the activity of
oxidative phenomena occurring, for instance, during pathophysiological processes. Although evidence shows that antioxidant
treatment results in cytoprotection, the potential clinical benefit deriving from both nutritional and supplemental antioxidants
is still under wide debate. In this line, the inappropriate assumption of some lipophylic vitamins has been associated with
increased incidence of cancer rather than with beneficial effects. 相似文献
88.
Rossella Grande Simone Carradori Valentina Puca Irene Vitale Andrea Angeli Alessio Nocentini Alessandro Bonardi Paola Gratteri Paola Lanuti Giuseppina Bologna Pasquale Simeone Clemente Capasso Viviana De Luca Claudiu T. Supuran 《International journal of molecular sciences》2021,22(21)
Helicobacter pylori, a Gram-negative neutrophilic pathogen, is the cause of chronic gastritis, peptic ulcers, and gastric cancer in humans. Current therapeutic regimens suffer from an emerging bacterial resistance rate and poor patience compliance. To improve the discovery of compounds targeting bacterial alternative enzymes or essential pathways such as carbonic anhydrases (CAs), we assessed the anti-H. pylori activity of thymol and carvacrol in terms of CA inhibition, isoform selectivity, growth impairment, biofilm production, and release of associated outer membrane vesicles-eDNA. The microbiological results were correlated by the evaluation in vitro of H. pylori CA inhibition, in silico analysis of the structural requirements to display such isoform selectivity, and the assessment of their limited toxicity against three probiotic species with respect to amoxicillin. Carvacrol and thymol could thus be considered as new lead compounds as alternative H. pylori CA inhibitors or to be used in association with current drugs for the management of H. pylori infection and limiting the spread of antibiotic resistance. 相似文献
89.
Raisins and Currants as Conventional Nutraceuticals in Italian Market: Natural Occurrence of Ochratoxin A 下载免费PDF全文
Francesca Fanelli Giuseppe Cozzi Assunta Raiola Irene Dini Giuseppina Mulè Antonio F. Logrieco Alberto Ritieni 《Journal of food science》2017,82(10):2306-2312
The healthy consumers make a strong pressure to natural products that can prevent the chronic diseases and improve the general health status, and therefore an important aspect that have to be considered is the safe level of the nutraceuticals. This study reports the occurrence of Ochratoxin A (OTA) and associated fungal contamination in 35 samples of dried vine fruits imported in the European community potentially used for the development of new nutraceutical supplements. High pressure liquid chromatography analysis identified 18 samples as contaminated by OTA with an average level of 2.6 μg/kg. OTA was measured in 4 samples of currants (mean value of 6.6 μg/kg) and 13 samples of raisins (mean value of 1.4 μg/kg). In one sample of currants and one of raisins from Turkey OTA exceeded the limits set by European Commission of 10 μg/kg, being contaminated with 12.61 and 15.99 μg/kg, respectively. All the positive samples were confirmed by Orbitrap Q Exactive through their molecular weight and the corresponding fragmentation. The worldwide consumption of dried vine fruits contributed to OTA exposure in several group of consumers. In particular, considering the potential nutraceutical approach, this consumption may be represent a severe risk for healthy consumers that consider these products like healthy and salutistic for their contents in antioxidants, flavonoids, and polyphenols. Data reported in this study confirmed the need to regularly monitor mycotoxin levels in these food products and optimize the process of fruits drying in order to reduce the development of toxigenic molds. 相似文献
90.
Calogero Caruso Mattia Emanuela Ligotti Giulia Accardi Anna Aiello Giovanni Duro Damiano Galimberti Giuseppina Candore 《International journal of molecular sciences》2022,23(10)
Several studies on the genetics of longevity have been reviewed in this paper. The results show that, despite efforts and new technologies, only two genes, APOE and FOXO3A, involved in the protection of cardiovascular diseases, have been shown to be associated with longevity in nearly all studies. This happens because the genetic determinants of longevity are dynamic and depend on the environmental history of a given population. In fact, population-specific genes are thought to play a greater role in the attainment of longevity than those shared between different populations. Hence, it is not surprising that GWAS replicated associations of common variants with longevity have been few, if any, as these studies pool together different populations. An alternative way might be the study of long-life families. This type of approach is proving to be an ideal resource for uncovering protective alleles and associated biological signatures for healthy aging phenotypes and exceptional longevity. 相似文献