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991.
Myleidi Vera Claudio Mella Daniel Palacio Srivathsava Surabhi Bruno Boury Karim Bouchmella Jong-Ryul Jeong Bruno F. Urbano 《应用聚合物科学杂志》2024,141(8):e54986
The properties of macroscopic polymer nanocomposites are highly dependent on the nanoparticle–polymer interfacial region, which varies with the morphology of the nanoparticles. Herein, we used TiO2 nanofillers with very low aspect ratio, the same chemical composition, and surface functions, but different geometries (nanospheres and nanoplates) dispersed in a poly(acrylic acid) matrix to analyze the influence of the nanoparticle geometry on the properties of nanocomposite hydrogels. The geometry was found to affect the swelling and rheological properties of the nanocomposite polymers. Particularly, the yield strain (from 25% to 130%), modulus (from 17,500 to 25,000 Pa), and brittleness of nanoplates based nanocomposite increased more significantly. Finite-difference time-domain simulations demonstrated that nanoplates increased the wavelength of the absorption maxima (224 nm for NS to 240 nm for NP) and charge distribution. The results obtained in this research indicate that the nanofiller shape markedly influences the rheological properties of the nanocomposite polymers, opening the door to further research focused on polymer–nanofiller interactions, and their effect on the macroscopic properties of the nanocomposites. 相似文献
992.
Big data has recently been recognised as one of the most important areas of future technology. It has attracted the attention of many industries, since it has the potential to provide companies with high business value. This paper examines the forms of business value that companies can create from big data analytics investments, the direct impacts it has on the financial performance of a firm, and the mediating effects of market performance and customer satisfaction. Drawing on the resource-based view theory, this study demonstrates that the business value achieved from investments in big data analytics leads to advantages in terms of the financial performance of a firm. The results offer evidence of the existence of a customer satisfaction mediation effect and of the absence of a market performance mediation effect. Theoretical and practical implications are discussed at the end of the paper. 相似文献
993.
In this work, the effects on the volatile profile of the pre-fermentative substitution of SO2 with lysozyme and oenological tannins were studied in white wines. At the same time, in order to understand the changes of volatile compounds in SO2-free wines, the evolution of volatiles was evaluated over 1 year of storage in bottles. For this purpose, a number of laboratory scale fermentations of SauvignonBlanc musts were carried out and the effects of three variables (SO2, lysozyme and oenological tannins) were investigated by means of GC–MS analysis. Results showed that the replacement of SO2 with lysozyme and oenological tannins influenced the volatile composition of wines at the end of the alcoholic fermentation. Wines fermented with SO2 showed higher total alcohol amounts, while the presence of oenological tannins augmented the level of esters. The presence of SO2 influenced also the alcohols and esters profiles of wines during bottle storage. Moreover, the presence of oenological tannins displayed a positive role in maintaining the amounts of esters over certain levels in wine stored for 1 year, likely due to their oxygen scavenging ability. By contrast, acids were less affected by the investigated adjuvants both at the end of the alcoholic fermentation and during the storage time. 相似文献
994.
There is increasing interest in effective decontamination treatments because healthy food-producing animals can harbor food-borne pathogens and complete prevention of contamination during slaughter can hardly be warranted. Thus we reviewed the available literature and appraised the antibacterial activity of physical, chemical and biological interventions applied on cattle hides and beef carcasses. Based on the evaluated studies, the efficacy of water sprayings, organic acids and their combinations was most frequently investigated for the decontamination of cattle hides and beef carcasses. Most data originated from laboratory-based studies using inoculated samples and extrapolation of these results to commercial practices is restricted. Application of interventions at slaughter plants reduced the bacterial loads on hides and carcasses to some extent, but reductions were clearly lower than those obtained under laboratory conditions. Thus hot water, steam, acetic acid or lactic acid treatment mainly yielded bacterial reductions below two orders of magnitude on carcasses. Under commercial conditions, the use of multiple sequential interventions at different points during slaughter must also be considered in order to enhance the microbiological safety of carcasses. On the other hand, decontamination treatments always must be considered part of an integral food safety system. 相似文献
995.
Giuseppe Mannino Piera Iovino Antonino Lauria Tullio Genova Alberto Asteggiano Monica Notarbartolo Alessandra Porcu Graziella Serio Giorgia Chinig Andrea Occhipinti Andrea Capuzzo Claudio Medana Luca Munaron Carla Gentile 《International journal of molecular sciences》2021,22(5)
Hypercholesterolemia is one of the major causes of cardiovascular disease, the risk of which is further increased if other forms of dyslipidemia occur. Current therapeutic strategies include changes in lifestyle coupled with drug administration. Statins represent the most common therapeutic approach, but they may be insufficient due to the onset of resistance mechanisms and side effects. Consequently, patients with mild hypercholesterolemia prefer the use of food supplements since these are perceived to be safer. Here, we investigate the phytochemical profile and cholesterol-lowering potential of Protium heptaphyllum gum resin extract (PHE). Chemical characterization via HPLC-APCI-HRMS2 and GC-FID/MS identified 13 compounds mainly belonging to ursane, oleanane, and tirucallane groups. Studies on human hepatocytes have revealed how PHE is able to reduce cholesterol production and regulate the expression of proteins involved in its metabolism. (HMGCR, PCSK9, LDLR, FXR, IDOL, and PPAR). Moreover, measuring the inhibitory activity of PHE against HMGR, moderate inhibition was recorded. Finally, molecular docking studies identified acidic tetra- and pentacyclic triterpenoids as the main compounds responsible for this action. In conclusion, our study demonstrates how PHE may be a useful alternative to contrast hypercholesterolemia, highlighting its potential as a sustainable multitarget natural extract for the nutraceutical industry that is rapidly gaining acceptance as a source of health-promoting compounds. 相似文献
996.
Lorenzo Migliorini Claudio Piazzoni Kaija Pohako-Esko Marta Di Girolamo Andrea Vitaloni Francesca Borghi Tommaso Santaniello Alvo Aabloo Paolo Milani 《Advanced functional materials》2021,31(27):2102180
The fabrication and characterization of green, flexible, and ultra-thin supercapacitors that are able to operate above 1.5 V is reported, using an all-printed fabrication process. The devices are produced by aqueous spray casting of a natural-derived electrolyte ionogel composed by 2-hydroxyethyl cellulose and by the ionic liquid choline lactate, while the electrodes are composed of highly porous nanostructured carbon films deposited by supersonic cluster beam deposition (SCBD). The obtained supercapacitors (device thickness < 10 μm) are stable to bending and they possess power values up to 120 kW kg–1. The combination of aqueous spray casting and SCBD constitutes a versatile, scalable, and eco-friendly fabrication process able to directly print interconnected elements suitable for transient electronic systems. 相似文献
997.
Agnieszka Kamiska Giovanni Luca Romano Robert Rejdak Sandrine Zweifel Michal Fiedorowicz Magdalena Rejdak Anahita Bajka Rosario Amato Claudio Bucolo Teresio Avitabile Filippo Drago Mario Damiano Toro 《International journal of molecular sciences》2021,22(9)
Glaucoma is a heterogeneous group of chronic neurodegenerative disorders characterized by a relatively selective, progressive damage to the retinal ganglion cells (RGCs) and their axons, which leads to axon loss and visual field alterations. To date, many studies have shown the role of various elements, mainly metals, in maintaining the balance of prooxidative and antioxidative processes, regulation of fluid and ion flow through cell membranes of the ocular tissues. Based on the earlier and current research results, their relationship with the development and progression of glaucoma seems obvious and is increasingly appreciated. In this review, we aimed to summarize the current evidence on the role of trace elements in the pathogenesis and prevention of glaucomatous diseases. Special attention is also paid to the genetic background associated with glaucoma-related abnormalities of physiological processes that regulate or involve the ions of elements considered as trace elements necessary for the functioning of the cells. 相似文献
998.
Aylanna P. M. de Araujo Leandro Micheloti Claudio S. Kiminami Piter Gargarella 《Materials Science & Technology》2020,36(11):1205-1214
Improvements in the mechanical strength of Al–Fe–Cr–Ti alloys have been demonstrated when non-equilibrium microstructures are developed. This paper investigated the effect of cooling rate and composition on the phase formation, microstructure and properties of new Al96.6Fe1.5Cr1.7Ti0.2 and Al91.6Fe4.9Cr2.2Ti1.3 (at.-%) alloys. Wedge-shaped samples produced by suction casting were characterised by optical, scanning electron microscopy, differential scanning calorimetry, X-ray diffraction, energy dispersive X-ray spectroscopy and microhardness. The results showed that the morphology and size of the phases precedent of the flower-like phases change from small, spherical particles to large flower-like phases with decreasing the cooling rate. The presence of intermetallic phases Al13Fe4, Al13Cr2 and Al3Ti in the Al91.6Fe4.9Cr2.2Ti1.3 alloy, resulted in a hardness 1.6 times higher compared to the Al96.6Fe1.5Cr1.7Ti0.2 alloy. 相似文献
999.
Alice Galbiati Blasco Morozzo della Rocca Claudio Tabolacci Simone Beninati Alessandro Desideri Gaio Paradossi 《Materials science & engineering. C, Materials for biological applications》2011,31(8):1653-1659
Capsular microvectors are an important tool in the recent research field of nanomedicine to address a drug cargo for the therapeutic treatment of several pathologies. In this study we describe how the product of the conjugation of the polysaccharide chitosan with folate can be used as a coating of poly (vinyl alcohol), PVA, based microcapsules for an efficient targeting of HeLa cells. The influence of the coating on the bioadhesive properties of the vector and on its cargo capacity was also considered using camptothecin as an anticancer drug model. The coating strategy was finalized to exploit the good chemical versatility of PVA, used to form the shell of the vector. This study is a follow up of an investigation activity aiming to show the potentialities of PVA-shelled microcapsules or microbubbles as injectable microdevices supporting a theranostic approach for different types of tumour. 相似文献
1000.
Anca Costescu Badea Claudio M. Rocco S.Stefano Tarantola Ricardo Bolado 《Reliability Engineering & System Safety》2011,96(6):651-662
In this paper we propose to use an aggregation rule derived from the Group Decision Theory, and based on the ranks of a set of individual indicators, for building a family of composite indicators for the security of energy supply. This family of composite indicators depends on a parameter associated with the risk-averse level of the decision maker, which can hence vary continuously from risk-prone to risk-averse. It represents a valuable and objective instrument to evaluate the degree of security of energy supply of different countries without entering into controversial matters related to the choice of the weights. This methodology can be used to aggregate either ranks or normalized values of the individual indicators. We apply it to a set of individual indicators, accounting for different dimensions of the security of supply and derived from the outputs of an energy system model. We study the evolution in time of the countries’ performances, as well as the propagation of the uncertainties associated with the individual indicators to the composite. We also studied the robustness of such composite indicators with respect to the risk-averse level. 相似文献