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991.
Raffaele Romano Felicia Masucci Anella Giordano Salvatore Spagna Musso Daniele Naviglio Antonello Santini 《International Dairy Journal》2010,20(12):858-862
To evaluate the effect of supplementing the diet of Comisana sheep with by-products from industrial tomato manufacture on the fat composition and conjugated linoleic acid (CLA) content of milk fat, two groups of 50 ewes each were fed either total mixed ration standard (TMRS) or total mixed ration with added tomato by-products (TMRA). Milk fat composition was determined by high-resolution gas chromatography (HRGC). The milk fat content for the animals fed the TMRA diet increased by 6.41% (P < 0.01) after six weeks, compared with the animals fed the TMRS diet. The CLA content in the milk fat for the group of animals fed the TMRA diet was 19.8% (P < 0.05) higher than for those fed the TMRS diet, and reached 1.33 g 100 g?1 fat, while the polyunsaturated fatty acid (PUFA) content increased by a 6.43% (P < 0.05) and reached 7.12 g 100 g?1 fat. The fatty acid composition showed an increase in the amount of polyunsaturated fatty acids. The n ? 3:n ? 6 ratio increased by 13% in the milk from sheep fed with the TMRA diet. These observations were confirmed by triglyceride analysis, which showed a decrease in the amount of short-chain (C28–C32) and medium-chain (C34–C42) triglycerides after six weeks, while the opposite was observed for the long-chain triglycerides (C44–C54). 相似文献
992.
The aims of this study were the monitoring of the microbial dynamics by means of a polyphasic approach based on conventional isolation techniques and PCR-DGGE-based methods in different chestnut-based sourdoughs and the evaluation of the impact of fermentation on volatile organic compounds formation during sourdoughs ripening. Members of the Lactobacillus plantarum group and Pediococcus pentosaceous dominated the sourdough ecosystems. Nevertheless, RAPD-PCR allowed recording a relevant genotypic biodiversity among strains coming from gluten-free flour combinations. Volatile compounds were characterised by GC/MS. A total of 59 volatile compounds were identified, mainly alcohols, esters, acids, aldehydes and ketones. Principal component analysis of samples at the beginning and at the end of ripening offered a good separation of the samples and highlighted the effect of fermentation on the sensorial profile. 相似文献
993.
Dr. Paola Franco Prof. Alfonso Carotenuto Dr. Cristina Marcozzi Dr. Giuseppina Votta Dr. Ciro Sarno Dr. Ingram Iaccarino Dr. Diego Brancaccio Dr. Anna De Vincenzo Prof. Ettore Novellino Prof. Paolo Grieco Dr. Maria Patrizia Stoppelli 《Chembiochem : a European journal of chemical biology》2013,14(7):882-889
Functional analysis of isolated protein domains may uncover cryptic activities otherwise missed. The serine protease urokinase (uPA) has a clear‐cut motogen activity that is catalytically independent and resides in its amino‐terminal growth factor domain (GFD, residues 1‐49) and connecting peptide region (CP, residues 132–158). To functionally dissect the CP region, we analysed the biological activity of two synthetic peptides corresponding to the N‐terminal [uPA‐(135–143), residues 135–143] and C‐terminal [uPA‐(144–158), residues 144–158] CP subregions. Most of the chemotactic activity of connecting peptide‐derived peptide (CPp, [uPA‐(135–158)]) for embryonic kidney HEK293/uPAR‐25 cells is retained by uPA‐(144–158) at nanomolar concentrations. In contrast, uPA‐(135–143) inhibits basal, CPp ‐, vitronectin‐ and fibronectin‐induced cell migration. Radioreceptor binding assays on intact HEK293 cells revealed that uPA‐(135–143) and uPA‐(144–158) are both able to compete with [125I]‐CPp, albeit with different binding affinities. The consequences of phospho‐mimicking, S138E substitution, were studied using [138E]uPA‐(135–158) and [138E]uPA‐(135–143) peptides. Unlike CPp, [138E]uPA‐(135–158) and [138E]uPA‐(135–143) exhibit remarkable inhibitory properties. Finally, analysis of the conformational preferences of the peptides allowed to identify secondary structure elements exclusively characterising the stimulatory CPp and uPA‐(144–158) versus the inhibitory uPA‐(135–143), [138E]uPA‐(135–158) and [138E]uPA‐(135–143) peptides. In conclusion, these data shed light on the cryptic activities of uPA connecting peptide, revealing the occurrence of two adjacent regions, both competing for binding to cell surface but conveying opposite signalling on cell migration. 相似文献
994.
995.
Paola Fabbri Luca Valentini Jasmin Hum Rainer Detsch Aldo R. Boccaccini 《Materials science & engineering. C, Materials for biological applications》2013,33(7):3592-3600
Highly porous 45S5 Bioglass®-based scaffolds fabricated by a foam replication technique were coated with electrically conductive organic–inorganic hybrid layers containing graphene by a solution method. α,ω-Triethoxysilane terminated poly (ethylene glycol) and tetraethoxysilane were used as the precursors of the organic–inorganic hybrid coatings, that contained 1.5 wt.% of homogeneously dispersed graphene nanoplatelets. The resulting coated scaffolds retained their original high porosity and interconnected pore structure after coating. The presence of graphene did not impair the bioactivity of the scaffolds in simulated body fluid.Initial tests carried out using MG-63 cells demonstrated that both uncoated scaffolds and scaffolds coated with organic/inorganic hybrids containing graphene offered the cultured cells an adequate surface for cell attachment, spreading and expression of extracellular matrix. The results showed that scaffolds coated with graphene are biocompatible and they can support cellular activity. The electrical conductivity introduced by the coating might have the potential to increase tissue growth when cell culture is carried out under an applied electric field. 相似文献
996.
Silvia Perego Alessandra Zabeo Emiliano Marasco Paola Giussani Amelia Fiorilli Guido Tettamanti Anita Ferraretto 《Journal of Functional Foods》2013,5(2):847-857
Dietary calcium intake is associated with colon cancer incidence due to its ability to modulate proliferation and apoptosis, cellular function directly linked to normal or tumour cell phenotype. In milk calcium is associated with casein whose hydrolysis produces the casein phosphopeptides (CPPs). CPPs induce calcium uptake in differentiated HT-29 and Caco2 cells. The aim of the present study was to explore: (i) the interaction between CPPs and the TRPV6 calcium channel in HT-29 and Caco2 cells; (ii) CPP effects on Caco2 cell functions. By reducing the expression of TRPV6 through small interfering RNA (siRNA), a decrease in cell response to CPPs was monitored in Caco2 cells (about 56%) but not in HT-29 cells. CPPs increased apoptosis both in undifferentiated and in transfected Caco2 cells. Based on the reported involvement of TRPV6 in cancer development, the results presented for CPPs may be helpful for their consideration as functional food ingredients. 相似文献
997.
998.
The Historical Bardini Museum in Florence is a representative paradigm of the Italian Museum Building, and it is very suitable to serve as an exemplary pilot project for the restoration of historical museums. This article presents results of the architectural and energy retrofitting carried out applying appropriate and strategic low-energy and sustainable techniques and of the monitoring campaign (IAQ, thermal comfort, light, acoustic) performed first to evaluate the existing situation and then to verify comfort parameters and the energy consumption after works. The Bardini Museum participates, as Italian case study, to the European MUSEUMS project, financed by EU Commission in the Fifth Framework Programme. The result of this project is to provide also with a direct guidance, complete with architectural and engineering examples, for design professionals and museum authorities, setting a new standard for energy consumption in museum buildings. In parallel, it has aimed to disseminate effective information for designers and local authorities and to demonstrate the efficiency of the measures in order to promote them in efficient market promotion, penetration and utilization. 相似文献
999.
Laura Analía Campa?one Carlos A. Paola Rodolfo H. Mascheroni 《Food and Bioprocess Technology》2012,5(2):738-749
This paper describes the development of a simulation model for heating of foods in microwave ovens and its uses to optimize
food heating strategies. The solution of the coupled energy and mass microscopic balances considers the electromagnetic energy
absorption as well as temperature-dependent thermal, transport, and dielectric properties. The microscopic balances are highly
nonlinear coupled differential equations, which were solved using finite element software (Comsol Multiphysics). Maxwell equations
were employed in order to describe the interaction between electromagnetic radiation and food. The mathematical model allowed
the evaluation of the effect of product size and composition in the temperature profiles that developed inside the food that
was radiated either on one or both sides. In order to improve the nonuniform temperature profiles that occurred within foods
under continuous operation, different operation schemes were evaluated: intermittent cycles, joint action of microwaves with
air impingement, and the effect of interference of electromagnetic waves. 相似文献
1000.
Xiaoting Wang Nick Waite Paola Murcia Keith Emery Myles Steiner Fouad Kiamilev Keith Goossen Christiana Honsberg Allen Barnett 《Progress in Photovoltaics: Research and Applications》2012,20(2):149-165
To achieve high energy conversion efficiency, a solar module architecture called lateral spectrum splitting concentrator photovoltaics (LSSCPV) is being developed. LSSCPV can concentrate available sunlight and laterally split a single beam into bands with different spectra for absorption by different solar cells with band gaps matched to the split spectrum. Test assemblies of a sample LSSCPV architecture were constructed, each of which contains four p–n junctions and two optical pieces. Independent experiments or simulations had been implemented on the components but by using optimal assumptions. In order to examine the actual performances of all the components, which are dependent on each other and the light source, direct outdoor measurements were made. A set of self‐consistent efficiency definitions was articulated and a test bed was developed to measure the parameters required by the efficiency calculation. By comparing the component efficiency items derived from the outdoor measurement and the expected values based on independent simulations, the potential opportunities for efficiency improvement are determined. In the outdoor measurement at the University of Delaware, the optical component demonstrated 89·1% efficiency. Additional assemblies were tested at the National Renewable Energy Laboratory. One assembly demonstrated 36·7% submodule efficiency, which compares favorably with the 32·6% previously reported verified submodule efficiency. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献