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81.
The genus Thymus L. consists of many species of herbaceous perennials and sub-shrubs. A chemical characterisation of a collection of Thymus spp. originated from regions of Southern Italy was performed using GC and GC/MS. The accessions were collected from various natural habitats of the Basilicata and Puglia Regions and transferred into a new uniform environment. The study showed that amongst the 22 components of the oils the most recurrent ones were geraniol, thymol and α-terpinene followed by linalool, citral and trans-caryophillene. Cluster analysis led to the identification of two chemotypes: geraniol and thymol/α-terpinene; only a biotype remained separate from all others, probably because of its high content linalool (58%). 相似文献
82.
Both industry and academia have shown a growing interest in materials with antimicrobial properties suitable for food packaging applications. In this study, we prepared and characterized thin films of ethylene-co-vinyl acetate (EVA) copolymer with antimicrobial properties. The films were prepared with a film blowing process by incorporating a nisin preparation as an antimicrobial agent in the melt. Two grades of EVA containing 14 and 28% (wt/wt) vinyl acetate (EVA 14 and EVA 28, respectively) and two commercial formulations of nisin with different nominal activities were used. The effect of the nisin concentration also was evaluated. The films with the highest antimicrobial activity were those formulated with nisin at the highest activity and EVA with the highest content of vinyl acetate. The use of the commercial formulation of nisin with high activity in the EVA films allowed reduction in the amount of nisin needed to provide antimicrobial properties. Consequently, the mechanical properties of these films were only slightly inferior to those of the pure polymers. In contrast, films prepared by incorporating more of the nisin with lower activity had poor mechanical properties. The effect of different processing temperatures used in the preparation of the films on the antimicrobial properties of the films also was evaluated. The materials displayed antimicrobial properties even when they were prepared at temperatures as high as 160 °C, probably because of the very short processing time (60 to 90 s) required for preparation. 相似文献
83.
Storelli MM Normanno G Barone G Dambrosio A Errico L Garofalo R Giacominelli-Stuffler R 《Journal of food protection》2012,75(1):189-194
Mercury, cadmium, and lead concentrations were determined in various fishery products (fishes, cephalopod molluscs, and crustaceans) imported into Italy from many European and non-European coastal countries. Considerable differences were found in the concentrations of these metals among the products tested. The highest mean Hg concentration was found in fishes (0.21 μg g(-1) wet weight), whereas cephalopods had the highest mean Cd concentration (0.35 μg g(-1) wet weight). Swordfish (0.80 μg g(-1) wet weight), longtail tuna (0.53 μg g(-1) wet weight), and thornback ray (0.52 μg g(-1) wet weight) had the highest concentrations of Hg, whereas maximum Cd concentrations were found in samples of common cuttlefish (0.85 μg g(-1) wet weight) and common octopus (0.64 μg g(-1) wet weight). The majority of the samples analyzed were in compliance with European Union legislation, except for a few cases. The calculated mean weekly intakes of Hg, Cd, and Pb through consumption of the fishery products tested were all below the legislated respective provisional tolerable weekly intakes. In general, the samples analyzed were considered safe to eat with regard to the metal concentrations found and the allowable intakes based on legislation. Nevertheless, the consumption of some species may be of significant importance for consumer health. 相似文献
84.
Thermophiles as Potential Source of Novel Endotoxin Antagonists: the Full Structure and Bioactivity of theLipo‐oligosaccharide from Thermomonas hydrothermalis 下载免费PDF全文
Dr. Flaviana Di Lorenzo Dr. Ida Paciello Dr. Luigi Lembo Fazio Dr. Luciana Albuquerque Dr. Luisa Sturiale Prof. Milton S. da Costa Prof. Rosa Lanzetta Prof. Michelangelo Parrilli Prof. Domenico Garozzo Prof. Maria Lina Bernardini Dott. Alba Silipo Prof. Antonio Molinaro 《Chembiochem : a European journal of chemical biology》2014,15(14):2146-2155
Thermomonas hydrothermalis is a Gram‐negative thermophilic bacterium that is able to live at 50 °C. This ability is attributed to chemical modifications, involving those to bacterial cell‐wall components, such as proteins and (glyco)lipids. As the main component of the outer membrane of Gram‐negative bacteria, lipopolysaccharides (LPSs) are exposed to the environment, thus they can undergo structural chemical changes to allow thermophilic bacteria to live at their optimal growth temperature. Furthermore, as one of the major target of the eukaryotic innate immune system, LPS elicits host immune response in a structure‐dependent mode; thus the uncommon chemical features of thermophilic bacterial LPSs might exert a different biological action on the innate immune system—an antagonistic effect, as shown in studies of LPS structure–activity relationship in the ongoing research into antagonist LPS candidates. Here, we report the complete structural and biological activity analysis of the lipo‐oligosaccharide isolated from Thermomonas hydrothermalis, achieved by a multidisciplinary approach (chemical analysis, NMR, MALDI MS and cellular immunology). We demonstrate a tricky and interesting structure combined with a very interesting effect on human innate immunity. 相似文献
85.
Dr. Riccardo De Ricco Dr. Daniela Valensin Dr. Simone Dell'Acqua Prof. Dr. Luigi Casella Dr. Christelle Hureau Prof. Dr. Peter Faller 《Chembiochem : a European journal of chemical biology》2015,16(16):2319-2328
Copper binding to α‐synuclein (aS) and to amyloid‐β (Ab) has been connected to Parkinson's and Alzheimer's disease (AD), respectively, because Cu ions can modulate the peptide aggregation, and these Cu ? peptide complexes can catalyse the production of reactive oxygen species (ROS). In a significant proportion of AD brains, aggregation of aS and Ab has been detected, and it was proposed that Ab and aS interact with each other. Thus, we investigated the potential interactions of Ab and aS through their binding of copper(I) and copper(II). Additionally, β‐synuclein (bS) was investigated, due to its additional methionine residue, a potential CuI ligand. We found that: 1) the peptides containing the Cu‐binding domains Ab1–16, aS1–15 and bS1–15 have similar affinities towards CuII and towards CuI, with Ab1–16 being slightly stronger, 2) in the case of CuI, the additional Met residue in bS1–15 increased the affinity slightly, 3) the exchange of CuI/II between the two peptides is rapid (≤ms), 4) a/bS1–15 and Ab1–16 form a heterodimeric complex with CuII, 5) CuI probably promotes a transient ternary complex, 6) the different CuI/II coordination of Ab1–16, aS1–15 and bS1–15 impacts the capacity to produce ROS and to oxidise catechol, and 7) when Ab1–16, aS1–15 and Cu are present, the ROS production more closely resembles that by Ab1–16. The work gives insights into the coordination chemistry of these related peptides, and the relevance of coordination differences, the ternary complex and ROS production are discussed. 相似文献
86.
The evaluation of the work of a researcher and its impact on the research community has been deeply studied in literature through the definition of several measures, first among all the h-index and its variations. Although these measures represent valuable tools for analyzing researchers?? outputs, they usually assume the co-authorship to be a proportional collaboration between the parts, missing out their relationships and the relative scientific influences. In this work, we propose the d-index, a novel measure that estimates the dependence degree between authors on their research environment along their entire scientific publication history. We also present a web application that implements these ideas and provides a number of visualization tools for analyzing and comparing scientific dependences among all the scientists in the DBLP bibliographic database. Finally, relying on this web environment, we present case and user studies that highlight both the validity and the reliability of the proposed evaluation measure. 相似文献
87.
Gianluca Paravati Andrea Sanna Fabrizio Lamberti Luigi Ciminiera 《Mobile Networks and Applications》2011,16(3):385-393
Wireless communication advances have enabled emerging video streaming applications to mobile handheld devices. For example,
it is possible to display and interact with complex 3D virtual environments on mobile devices that don’t have enough computational
and storage capabilities (e.g. smart phones, PDAs) through remote rendering techniques, where a server renders 3D data and
streams the corresponding image flow to the client. However, due to fluctuations in bandwidth characteristics and limited
mobile device CPU capabilities, it is extremely challenging to design effective systems for streaming interactive multimedia
over wireless networks. This paper presents a novel approach based on a controller that can automatically adjust streaming
parameters basing on feedback measures from the client device. Experimental results prove the effectiveness of the proposed
solution in coping with bandwidth changes, thus providing high Quality of Service (QoS) in remote visualizations. 相似文献
88.
Luigi Catuogno Hans Löhr Mark Manulis Ahmad-Reza Sadeghi Christian Stüble Marcel Winandy 《Datenschutz und Datensicherheit - DuD》2010,34(5):289-294
Trusted Virtual Domains (TVDs) provide a secure IT infrastructure offering a homogeneous and transparent enforcement of access
control policies on data and network resources. In this article, we give an overview of the fundamental ideas and basic concepts
behind TVDs, present a realization of TVDs, and discuss application scenarios. 相似文献
89.
Desmin and troponin T are degraded faster in type IIb muscle fibers than in type I fibers during postmortem aging of porcine muscle 总被引:1,自引:0,他引:1
A novel approach was applied in this study to directly evaluate the effect of muscle fiber type on postmortem protein degradation. Porcine muscle fibers were isolated from longissimus muscle at day 1, 3, and 6 postmortem. Fibers were sorted by immunochemical myosin heavy chain isoform typing. Western blot analysis of fibers pooled separately into type I or IIb showed that the relative amounts of 39- and 50-kDa desmin degradation fragments at day 6, and 28- to 31-kDa fragments of troponin T fast type isoform (fTnT) at day 1 and 6 postmortem were higher in type IIb than in type I fibers. At day 6 troponin T slow type isoform (sTnT) was less degraded than fTnT in type I fibers. These results indicated greater rate and extent of proteolysis in type IIb than in type I fibers and higher susceptibility of fTnT to proteolysis than that of sTnT isoform. 相似文献
90.
Francesco Venditti Francesca Cuomo Andrea Ceglie Luigi Ambrosone Francesco Lopez 《Journal of hazardous materials》2010,173(1-3):552-557
The feasibility of utilizing CTAB–silica gelatin composite (C-SGC) to remove hexavalent chromium from aqueous solutions under different conditions was investigated. Removal of chromate was assessed through evaluation of the adsorption kinetics of chromate ions on the composite under equilibrium conditions in the presence of sulfate ions and at a slightly acidic pH condition (pH 5.8). Adsorption competition tests in the presence of sulfate ions showed that Cr(VI) was still effectively adsorbed from aqueous solution regardless of the presence of the competing anions. In fact, the adsorption kinetics performed at different initial chromate concentrations were unaffected by the presence of 100 mg L?1 sulfate ions (pH 7.5). The equilibrium adsorption data were fitted by Freundlich adsorption isotherms which confirmed that the adsorption efficiency of chromium on the CTAB–silica gelatin composite was unchanged in the presence of sulfate ions. Further, the adsorption process was shown to be pH dependent and more efficient at slightly acidic pH (5.8). These findings demonstrated a high specificity of the CTAB–silica gelatin composite for chromium, and highlight the possibility of using this matrix for efficient removal of chromium from industrial wastewater without the need to eliminate contaminant sulfate ions. 相似文献