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51.
Bardati F. Borrani A. Gerardino A. Lovisolo G.A. 《IEEE transactions on bio-medical engineering》1995,42(12):1201-1207
RF deep hyperthermia systems make use of phased arrays of applicators in order to heat tumors selectively while maintaining healthy tissue at normal temperatures. A new method for the array synthesis is proposed based on the identification of targets to be heated (tumors) and targets to be prevented from excess electromagnetic radiation. The best array feed for each target is found from the solution of the eigenvector problem for a positive definite Hermitian matrix defined for that target. The optimal feed in a global sense then results from a trade-off of the best feeds of individual targets enforced through minimization of an objective function aimed at weighting the distances of the globally optimal feed from the feed vectors optimized for each target separately. An application to the heating of a pelvis is provided as an example 相似文献
52.
Kevin Neumann Sarthak Jain Alessia Gambardella Dr. Sarah E. Walker Dr. Elsa Valero Dr. Annamaria Lilienkampf Prof. Mark Bradley 《Chembiochem : a European journal of chemical biology》2017,18(1):91-95
Molecules that undergo activation or modulation following the addition of benign external small‐molecule chemical stimuli have numerous applications. Here, we report the highly efficient “decaging” of a variety of moieties by activation of a “self‐immolative” linker, by application of water‐soluble and stable tetrazine, including the controlled delivery of doxorubicin in a cellular context. 相似文献
53.
Maurizio Avella Claudio Bozzi Ramiro dell'Erba Bonaventura Focher Annamaria Marzetti Ezio Martuscelli 《大分子材料与工程》1995,233(1):149-166
Composites of wheat straw fibers with polypropylene (iPP) and maleic anhydride modified polypropylene (iPPMA) were prepared. Before being mixed with polypropylene matrices, the wheat straw fibers were subjected to a steam explosion process that induces morphological and structural changes in lignocellulosic materials. Such changes are able to enhance the interactions with the thermoplastic matrix. Compared with iPP, the modified matrix (iPPMA) has shown higher mechanical performances (tensile and impact behavior) and a remarkable decrease of water absorption, that is one of the main drawbacks of natural fiber composites. Finally, the presence of covalent bonds between maleic anhydride and steam-exploded (STEX) fibers, by means of an esterification reaction, produced during the melt-mixing process, can explain the resulting good interfacial adhesion found in iPPMA-based composities. 相似文献
54.
Hexanitrohexaazaisowurtzitane (HNIW) or CL-20 is a caged structure polycyclic nitramine that may replace RDX and HMX as a common use energetic chemical. To provide insight into the environmental fate of CL-20 we photolyzed the chemical in a Rayonet photoreactor (254-350 nm) and with sunlight in aqueous solutions. Previously, we found that initial photodenitration of the monocyclic nitramine RDX leads to ring cleavage and decomposition. Presently, we found that photolysis of the rigid molecule CL-20 produced NO2-, NO3-, NH3, HCOOH, N2 and N2O. Using LC/MS (ES-) we detected several key intermediates carrying important information on the initial steps involved in the degradation of CL-20. The identities of the intermediates were confirmed using a uniformly ring labeled 15N-[CL-20]. When CL-20 was photolyzed in the presence of H2(18)O, D2O or 18O2 we obtained a product distribution suggesting that the energetic chemical degraded via at least two initial routes; one involved sequential homolysis of N-NO2 bond(s) and another involved photorearrangement prior to hydrolytic ring cleavage and decomposition in water. 相似文献
55.
Antonio Fabozzi Rosa Vitiello Irene Russo Krauss Mauro Iuliano Gaetano De Tommaso Angela Amoresano Gabriella Pinto Luigi Paduano Christopher Jones Martino Di Serio Gerardino D'Errico 《Journal of surfactants and detergents》2019,22(1):115-124
Amine-oxide surfactants have emerged as highly stable, nontoxic, and cost-effective constituents of detergent formulations, specifically as wetting agents and foam boosters. With the aim of enhancing their functional behavior, a new member of this family, N,N-dimethyl-2-propylheptan-1-amine oxide, bearing a branched alkyl tail (C10DAO-branched) was synthesized and purified using a simple and easily scalable strategy starting from 2-propylheptan-1-ol. 2D-nuclear magnetic resonance (NMR) and mass spectrometry confirm the obtainment of the desired product in high yield and purity. The protonation behavior of the branched surfactant is not affected by alkyl tail branching, as shown by potentiometric titrations. In contrast, surface activity and aggregation behavior of C10DAO-branched is dramatically different from that of the linear analog N,N-dimethyldecyl-1-amine oxide (C10DAO-linear), in that it occupies a higher area at the solution interface and aggregates at much higher concentration, forming larger aggregates, as detected using tensiometry and dynamic light scattering (DLS), respectively. Aggregation behavior of C10DAO-branched is less sensitive to pH variations. Foaming tests show that C10DAO-branched is a more effective foam booster than its linear analog, in both acidic and basic solutions. The experimental results indicate that the branched surfactant can be used in applications that require enhanced and pH-independent surface activity and foamability. 相似文献
56.
Annamaria Perna Amalia Simonetti Immacolata Intaglietta Adriano Sofo Emilio Gambacorta 《International Journal of Food Science & Technology》2012,47(9):1909-1917
Seventy‐eight samples of southern Italy honey from five different floral origins (chestnut, eucalyptus, citrus, multifloral and sulla) were screened to quantify the polyphenol and metal contents, evaluate the antioxidant activity and determine the correlations between the parameters analysed. The average polyphenol content was 12.06 mg gallic acid equivalent per 100 g honey and 7.92 mg quercetin equivalent per 100 g honey, for total phenolic and flavonoid contents, respectively. The antioxidant activity ranged from 58.40% (eucalyptus honey) to 60.42% (chestnut honey) in the ABTS assay, from 152.65 μm Fe (II) (citrus honey) to 881.34 μm Fe (II) (chestnut honey) in the FRAP assay, and from 54.29% (citrus honey) to 78.73% (chestnut honey) in the DPPH assay. Fe and Zn were the most abundant among the tested metals, while Cd, Co and Mo were those less present. Chestnut honey presented the highest polyphenol content, antioxidant activity and metal content. The correlations between the analysed parameters were statistically significant (P < 0.05). The correlations between metal content and both total phenolic and antioxidant activities were particularly interesting, suggesting a relationship between metal and polyphenol contents in honey. 相似文献
57.
New Anti-Nodal Monoclonal Antibodies Targeting the Nodal Pre-Helix Loop Involved in Cripto-1 Binding
Annalia Focà Luca Sanguigno Giuseppina Focà Luigi Strizzi Roberta Iannitti Rosanna Palumbo Mary J. C. Hendrix Antonio Leonardi Menotti Ruvo Annamaria Sandomenico 《International journal of molecular sciences》2015,16(9):21342-21362
Nodal is a potent embryonic morphogen belonging to the TGF-β superfamily. Typically, it also binds to the ALK4/ActRIIB receptor complex in the presence of the co-receptor Cripto-1. Nodal expression is physiologically restricted to embryonic tissues and human embryonic stem cells, is absent in normal cells but re-emerges in several human cancers, including melanoma, breast, and colon cancer. Our aim was to obtain mAbs able to recognize Nodal on a major CBR (Cripto-Binding-Region) site and to block the Cripto-1-mediated signalling. To achieve this, antibodies were raised against hNodal(44–67) and mAbs generated by the hybridoma technology. We have selected one mAb, named 3D1, which strongly associates with full-length rhNodal (KD 1.4 nM) and recognizes the endogenous protein in a panel of human melanoma cell lines by western blot and FACS analyses. 3D1 inhibits the Nodal-Cripto-1 binding and blocks Smad2/3 phosphorylation. Data suggest that inhibition of the Nodal-Cripto-1 axis is a valid therapeutic approach against melanoma and 3D1 is a promising and interesting agent for blocking Nodal-Cripto mediated tumor development. These findings increase the interest for Nodal as both a diagnostic and prognostic marker and as a potential new target for therapeutic intervention. 相似文献
58.
Antonella Castagna Chiara Dall’Asta Emma Chiavaro Gianni Galaverna Annamaria Ranieri 《Food and Bioprocess Technology》2014,7(8):2241-2250
In the present study, the possibility of enhancing phenolic and flavonoid concentration in tomato (Solanum lycopersicum L.) fruits by post-harvest irradiation with UV-B light was assessed. Fruits of the commercial cv Money Maker (MM) and the mutant genotype high pigment-1 (hp-1), constitutively rich in these compounds, were harvested at mature green and turning stages and left to ripen within climatic chambers where they were daily treated with UV-B radiation (1 h, 6.08 kJ/m2 day). In control chambers, UV-B radiation was screened by benzophenone-treated polyethylene film. The treatment was generally effective in increasing phenolic, flavonoid and flavonol concentration in both peel and flesh of MM and hp-1 fruits, although in this latter the positive response to UV-B treatment was mainly evident in fruits harvested at mature green stage. Following UV-B treatment, antioxidant activity increased in the peel of both genotypes independently from the harvesting stage and in the flesh of hp-1 fruits harvested at mature green stage. Hydroxycinnamic acids of both genotypes reacted to UV-B treatment differently depending on harvesting stage and tissue localisation, generally showing an increase in the peel of fruits harvested at mature green stage. With few exceptions, UV-B irradiation also induced a higher accumulation of individual flavonoids both in the peel and in the flesh of MM and hp-1 fruits independently from harvesting stage. Based on these results, UV-B irradiation can be considered a promising technique to increase the nutraceutical potential of tomato fruits by non-molecular tools. 相似文献
59.
Dr. Daniela Rossi Dr. Alice Pedrali Dr. Raffaella Gaggeri Dr. Annamaria Marra Dr. Luca Pignataro Dr. Erik Laurini Dr. Valentina Dal Col Prof. Maurizio Fermeglia Prof. Sabrina Pricl Dr. Dirk Schepmann Prof. Bernhard Wünsch Dr. Marco Peviani Dr. Daniela Curti Prof. Simona Collina 《ChemMedChem》2013,8(9):1514-1527
Our recent research efforts identified racemic RC‐33 as a potent and metabolically stable σ1 receptor agonist. Herein we describe the isolation of pure RC‐33 enantiomers by chiral chromatography, assignment of their absolute configuration, and in vitro biological studies in order to address the role of chirality in the biological activity of these compounds and their metabolic processing. The binding of enantiopure RC‐33 to the σ1 receptor was also investigated in silico by molecular dynamics simulations. Both RC‐33 enantiomers showed similar affinities for the σ1 receptor and appeared to be almost equally effective as σ1 receptor agonists. However, the R‐configured enantiomer showed higher in vitro hepatic metabolic stability in the presence of NADPH than the S enantiomer. Overall, the results presented herein led us to select (R)‐RC‐33 as the optimal candidate for further in vivo studies in an animal model of amyotrophic lateral sclerosis. 相似文献
60.
Martino Colonna Claudio Gioia Micaela Vannini Maurizio Fiorini Annamaria Celli Alessandro Minesso Roberto Cavalieri Uwe E. Kubillus 《Progress in Organic Coatings》2014
A new one-pot method for the melt synthesis of polyarylates based on resorcinol and phthalic acids has been developed. The method consists in the reaction of diphenyl carbonate, phthalic acids and resorcinol using titanium butoxide as catalyst. Model reactions have shown that the diaryl ester is generated in situ by reaction of the aromatic diacid and of the aromatic diol with diphenyl carbonate. It is thus possible to obtain polymers with tailored end-groups and molecular weight, by changing the molar ratio of the monomers and the reaction conditions. More specifically, we applied this method to the synthesis of low molecular weight polymers with carboxylic end-groups, suitable for powder coating applications. The literature actually reports that resorcinol based polyarylates present an outstanding long-term UV stability and therefore COOH terminated oligomers are highly promising materials for the preparation of super-durable powder coatings. 相似文献