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981.
Rosa Turco Riccardo Tesser Vincenzo Russo Rosa Vitiello Massimo Fagnano Martino Di Serio 《European Journal of Lipid Science and Technology》2020,122(1)
The world production of epoxidized vegetable oil, mainly epoxidized soybean oil, is continuously increasing because this product can have a wide range of applications. Non‐edible vegetable oils, recovered by the plants growing on marginal and polluted lands, represent a possible answer to industry versus food chain debate. Cardoon (Cynara cardunculus L.) seed oil can be considered as an interesting and sustainable alternative to edible soybean oil to make plasticizers. In this work, a comparison between different epoxidation methods of cardoon oil is depicted and argued, focusing on strong points and weaknesses for each of them. It is found that cardoon seed oil can be successfully epoxidized through feasible existing technologies, by peracids and hydrogen peroxide equally. Moreover, it is demonstrated that a “greener” cardoon oil epoxidation process is possible, by using hydrogen peroxide in the presence of commercial γ‐alumina as heterogeneous solid catalyst. Practical Applications: The paper analyzes the advantages and the problems of different epoxidation methods in order to obtain a final product with high quality and answer the environmental, social, and economic sustainability requirements. 相似文献
982.
Characterization of the Maillard reaction in bread crisps 总被引:3,自引:0,他引:3
Edoardo Capuano Antonella Ferrigno Iolanda Acampa Lamia Ait-Ameur Vincenzo Fogliano 《European Food Research and Technology》2008,228(2):311-319
Maillard reaction (MR) is one of the main chemical event occurring during baking. To study the reaction in bakery products,
a dry model system is more useful than an aqueous one. In this work, the effects of formulation and processing conditions
in a crisp bread system were investigated to test the effects of different additives on both the overall reaction and the
formation of MR products such as 5-hydroxymethyl-2-furaldehyde (HMF) and acrylamide. Cylindrical dough made up of flour, water
and yeast was baked at 180 °C for 35 min and the slices were toasted at different times/temperatures combinations. Browning
and water content were monitored along with the kinetic of formation of chemical indicators such as HMF and acrylamide also
calculating rate constants and activation energy. These parameters were also monitored in systems added with glycine and asparaginase.
During toasting water content follows an exponential trend, being the rate of water loss faster in the initial stage of toasting
and at higher temperature. Browning was more intense when toasting at higher temperature and a linear correlations between
browning (ΔL*, ΔE*), HMF and acrylamide concentration were observed when toasting at 180 °C. HMF and acrylamide content increased
with the toasting time and temperature. Their concentrations were strongly dependent on the water content of the final product,
and both the addition of glycine and asparaginase are effective in reducing acrylamide content. The addition of glycine enhanced
the browning of toasted bread, and slightly increased HMF content at any toasting temperature. The system characterized in
this work represents a suitable tool to study the development of the MR in dry systems. 相似文献
983.
Felgines C Texier O Besson C Vitaglione P Lamaison JL Fogliano V Scalbert A Vanella L Galvano F 《Molecular nutrition & food research》2008,52(8):959-964
Anthocyanins are natural dietary pigments that could be involved in various health effects. However their mechanisms of absorption are still not fully understood. The aim of this study was to evaluate the influence of glucose on anthocyanin absorption in rats. We first studied anthocyanin bioavailability in rats that received by gastric intubation approximately 53 micromol cyanidin 3-glucoside (Cy 3-glc) equivalents from a red orange extract with or without 2.51 mmol glucose. Neither 24-h urinary anthocyanin excretion nor plasma anthocyanin concentration was significantly affected by simultaneous ingestion of glucose. The influence of glucose (12, 42 or 72 mM) on intestinal absorption of Cy 3-glc (pure or from a red orange extract; approximately 12.3 microM) was further studied using an in situ intestinal perfusion model. Absorption of pure Cy 3-glc from the intestinal lumen was not significantly affected by the amount of glucose. However, intestinal absorption of Cy 3-glc from the red orange extract (6.49 +/- 1.44%, n = 6) was significantly less than that of pure Cy 3-glc (17.5 +/- 1.3%, n = 7) (p < 0.01) suggesting that the red orange extract contained other components that were able to interfere with Cy 3-glc intestinal absorption. This study has thus shown that glucose did not interfere with anthocyanin glucoside absorption. 相似文献
984.
Realizing and installing renewable energy plants have an environmental “footprint” that has to be evaluated to quantify the real impact of renewable technologies on the environment. Nowadays, the most important tool to evaluate this impact of a product is the Life Cycle Assessment (LCA).The aim of this work is to present a Life Cycle Assessment of an innovative solar technology, the molten salt concentrating solar power (CSP) plant combined with a biomass Back-Up Burner, developed by Italian Research Centre ENEA and able to produce clean electricity by using solar energy. The Life Cycle Assessment was carried out by means of the SimaPro7 software, one of the most used LCA software in the world.In the second part of the study the environmental performance of the CSP plant was compared with these of conventional oil and gas power plants. 相似文献
985.
Maryam Shafahi Vincenzo Bianco Kambiz Vafai Oronzio Manca 《International Journal of Heat and Mass Transfer》2010,53(7-8):1438-1445
Analytical models are utilized to investigate the thermal performance of rectangular and disk-shaped heat pipes using nanofluids. The liquid pressure, liquid velocity profile, temperature distribution of the heat pipe wall, temperature gradient along the heat pipe, thermal resistance and maximum heat load are obtained for the flat-shaped heat pipes utilizing a nanofluid as the working fluid. The flat-shaped heat pipe’s thermal performance using a nanofluid is substantially enhanced compared with one using a regular fluid. The nanoparticles presence within the working fluid results in a decrease in the thermal resistance and an increase in the maximum heat load capacity of the flat-shaped heat pipe. The existence of an optimum nanoparticle concentration level and wick thickness in maximizing the heat removal capability of the flat-shaped heat pipe was established. 相似文献
986.
987.
Rocco Cappellesso Filippo Nozzoli Federica Zito Marino Sara Simi Francesca Castiglione Vincenzo De Giorgi Carlo Cota Rebecca Senetta Giosu Scognamiglio Anna Maria Anniciello Anna Maria Cesinaro Mario Mandal Andrea Gianatti Maria Gabriella Valente Barbara Valeri Angela Rita Sementa Costantino Ricci Barbara Corti Giandomenico Roviello Angelo Paolo Dei Tos Renato Franco Daniela Massi 《International journal of molecular sciences》2021,22(22)
Atypical Spitz tumors (AST) deviate from stereotypical Spitz nevi for one or more atypical features and are now regarded as an intermediate category of melanocytic tumors with uncertain malignant potential. Activating NTRK1/NTRK3 fusions elicit oncogenic events in Spitz lesions and are targetable with kinase inhibitors. However, their prevalence among ASTs and the optimal approach for their detection is yet to be determined. A series of 180 ASTs were screened with pan-TRK immunohistochemistry and the presence of NTRK fusions was confirmed using FISH, two different RNA-based NGS panels for solid tumors, and a specific real time RT-PCR panel. Overall, 26 ASTs showed pan-TRK immunostaining. NTRK1 fusions were detected in 15 of these cases showing cytoplasmic immunoreaction, whereas NTRK3 was detected in one case showing nuclear immunoreaction. Molecular tests resulted all positive in only two ASTs (included the NTRK3 translocated), RNA-based NGS and real time RT-PCR were both positive in three cases, and FISH and real time RT-PCR in another two cases. In seven ASTs NTRK1 fusions were detected only by FISH and in two cases only by real time RT-PCR. The frequency of NTRK fusions in ASTs is 9%, with a clear prevalence of NTRK1 compared to NTRK3 alterations. Pan-TRK immunohistochemistry is an excellent screening test. Confirmation of NTRK fusions may require the use of different molecular techniques. 相似文献
988.
Through differential scanning calorimetry, isothermal crystallization from the melt of polytetrafluoroethylene (PTFE) has been investigated. PTFE was regarded as one of the polymers for which crystallization is so rapid that the samples crystallize during the cooling from the melt to the selected crystallization temperature. By contrast, we now report that a stochastic behavior is observed for isothermal melt‐crystallization of PTFE. In fact, on cooling very quickly the samples from the molten state to the selected crystallization temperature, crystallization during the cooling is randomly observed. Therefore, repeating the experiments until crystallization on cooling was absent, it was possible to investigate isothermal melt‐crystallization of PTFE. However, crystallization is very fast; in fact, crystallization kinetics can be followed just for very low undercoolings, while as the undercooling becomes as large as about 15°C, only secondary crystallization is observed. In both cases, the data have been examined through the well‐known Avrami analysis, taking into account the different physical meaning of the obtained parameters. For the first cases (actual crystallization kinetics) very low, noninteger Avrami exponents have been obtained. They have been related to the fractal dimension of the crystallites and their values to the morphological observations on PTFE. For the second cases, the typical low values of Avrami exponents of secondary crystallization are obtained. Moreover, isothermal melt‐crystallization of random fluorinated copolymers of tetrafluoroethylene with either hexafluoropropylene or perfluoromethylvinylether as comonomers has been studied and compared with that of PTFE. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1607–1613, 1999 相似文献
989.
Elena Chugunova Nurgali Akylbekov Alexey Dobrynin Alexander Burilov Carla Boga Gabriele Micheletti Vincenzo Frenna Edoardo Jun Mattioli Matteo Calvaresi Domenico Spinelli 《International journal of molecular sciences》2021,22(24)
This research focuses on the X-ray structure of 4,6-dichloro-5-nitrobenzofuroxan 1 and of some of its amino derivatives (4a, 4e, 4g, and 4l) and on DFT calculations concerning the nucleophilic reactivity of 1. We have found that by changing the solvent used for crystallization, it is possible to obtain 4,6-dichloro-5-nitrobenzofuroxan (1) in different polymorphic structures. Moreover, the different torsional angles observed for the nitro group in 1 and in its amino derivatives (4a, 4e, 4g, and 4l) are strictly dependent on the steric hindrance of the substituent at C-4. DFT calculations on the course of the nucleophilic substitution confirm the role of the condensed furoxan ring in altering the aromaticity of the carbocyclic frame, while chlorine atoms strongly influence the dihedral angle and the rotational barrier of the nitro group. These results corroborate previous observations based on experimental kinetic data and give a deep picture of the reaction with amines, which proceeds via a “non-aromatic” nucleophilic substitution. 相似文献
990.
Chiara Camponeschi Maria De Carluccio Susanna Amadio Maria Elisabetta Clementi Beatrice Sampaolese Cinzia Volont Maria Tredicine Vincenzo Romano Spica Rosa Di Liddo Francesco Ria Fabrizio Michetti Gabriele Di Sante 《International journal of molecular sciences》2021,22(24)
S100B is an astrocytic protein behaving at high concentration as a damage-associated molecular pattern molecule. A direct correlation between the increased amount of S100B and inflammatory processes has been demonstrated, and in particular, the inhibitor of S100B activity pentamidine has been shown to ameliorate clinical scores and neuropathologic-biomolecular parameters in the relapsing-remitting experimental autoimmune encephalomyelitis mouse model of multiple sclerosis. This study investigates the effect of arundic acid (AA), a known inhibitor of astrocytic S100B synthesis, in the chronic experimental autoimmune encephalomyelitis, which is another mouse model of multiple sclerosis usually studied. By the daily evaluation of clinical scores and neuropathologic-molecular analysis performed in the spinal cord, we observed that the AA-treated group showed lower severity compared to the vehicle-treated mice, particularly in the early phase of disease onset. We also observed a significant reduction of astrocytosis, demyelination, immune infiltrates, proinflammatory cytokines expression and enzymatic oxidative reactivity in the AA-treated group. Overall, our results reinforce the involvement of S100B in the development of animal models of multiple sclerosis and propose AA targeting the S100B protein as a focused potential drug to be considered for multiple sclerosis treatment. 相似文献