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91.
92.
This paperdeals with the problem of water-level control for an array ofcells by means of an hydraulic circuit. An on-off valve fillsall the cells, while each cell is drained by a single on-offvalve, so the control is intrinsically coupled. An optimal controlwith PWM (pulse width modulation) valves is carried out. At theend, simulation and experimental results are presented. The arrayof cells may find application as compensator for radiotherapy(Total Body Irradiation), by interposing the cells between thex-ray source and the patient: on-line water-level variationsin the cells allow local radiation dose control. 相似文献
93.
Toschi L Hilbig J Wintermantel T Engelhaupt A Walter A Fritzemeier KH Hillisch A 《ChemMedChem》2006,1(11):1237-1248
Subtype-selective estrogens are of increasing importance as tools used to unravel physiological roles of the estrogen receptors, ERalpha and ERbeta, in various species. Although human ERalpha and ERbeta differ by only two amino acids within the binding pockets, we and others recently succeeded in generating subtype-selective agonists. We have proposed that the selectivity of the steroidal compounds 16alpha-lactone-estradiol (16alpha-LE(2), hERalpha selective) and 8beta-vinyl-estradiol (8beta-VE(2), hERbeta selective) is based on the interaction of certain substituents of these compounds with essentially one amino acid in the respective ER binding pockets. For in vitro and ex vivo pharmacological experiments with these compounds we intended to use bovine tissues available from slaughterhouses in larger quantities. Using homology modeling techniques we determined that the amino acid conferring high hERbeta-selectivity to 8beta-VE(2) is not exchanged between human and bovine ERalpha and bovine ERbeta. Thus, we predicted our steroidal hERbeta-selective compound to exhibit only weak agonistic activity at bERbeta and that bovine tissue is therefore not suited for investigation of ERbeta functions. The situation is presumably identical for pig, sheep, and the common marmoset, whereas rats, mice, and rhesus macaques are appropriate animal models to study pharmacological effects of 8beta-VE(2) in vivo. This prediction was confirmed in transactivation studies assessing estradiol (E(2)) and the two subtype-selective ligands on bovine ERbeta and on a series of hERalpha and hERbeta with mutations in their respective ligand-binding pockets. We have shown that the detailed understanding of the interactions of a compound with its target protein enables the identification of relevant species for pharmacological studies. 相似文献
94.
Succi S Toschi F Capuzzi P Vignolo P Tosi MP 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2004,362(1821):1605-1612
We present a numerical study of the micro-dynamical roots of dissipation in two colliding mesoscopic clouds of point-like fermions as a function of the scattering length and of temperature approaching full quantum degeneracy. This study, which is motivated by current experiments on ultracold gaseous mixtures of fermionic atoms inside magnetic traps, combines the solution of the coupled Vlasov-Landau equations for the Wigner distribution functions with a locally adaptive importance-sampling technique for handling collisional interactions. The results illustrate the consequences of genuinely quantum collisional phenomena, and in particular the role of Pauli blocking in the transition to hydrodynamic behaviour. We also compare the computed quantum collision rate as a function of temperature in the weak-coupling case with theoretical results assuming that equilibrium distributions determine the quantum collision integral. 相似文献
95.
Chemical Composition and Sensory Quality of Tunisian ‘Sayali’ Virgin Olive Oils as Affected by Fruit Ripening: Toward an Appropriate Harvesting Time 下载免费PDF全文
Houda Nsir Amani Taamalli Enrico Valli Alessandra Bendini Tullia Gallina Toschi Mokhtar Zarrouk 《Journal of the American Oil Chemists' Society》2017,94(7):913-922
Herein, the influence of the ripeness of Tunisian Sayali olives on the chemical composition and sensory quality of virgin olive oils have been investigated, with a particular focus on minor metabolites. Towards this end, five samples (S1–S5) were produced from fruits at increasing stages of maturity and then analyzed. Quality indices (free acidity, peroxide value, specific extinction in UV, sensory characteristics) and composition in major (fatty acids) and minor compounds (squalene, pigments, tocopherols, phenolic compounds, volatile compounds), as well as oxidative stability, were evaluated. Significant variations for the most analytical parameters of Sayali samples were demonstrated, highlighting the impact of stage of ripening. In particular, at later stages of ripening a decreased tendency was seen in minor compounds that are able to inhibit lipid oxidation (tocopherols, carotenoids, squalene and polar phenolic compounds) and, as a consequence, in the oxidative stability value. Moreover, a higher intensity of positive sensory notes (fruity, bitter and pungent) characteristic of extra virgin olive oil were found for samples produced with less ripe olives. Finally, a deeper knowledge of the influence of this factor would be helpful to correctly manage the optimal fruit harvesting time for producers for this variety and to improve the marketing of extra virgin olive oils by using a promising secondary variety (with a high oxidative stability and an interesting fatty acid composition). 相似文献
96.
Effects of Olive Trees Age on the Minor Components of Oueslati Virgin Olive Oils Produced from Olives Harvested at Different Ripening Degrees 下载免费PDF全文
Fatma Chtourou Enrico Valli Alessandra Bendini Aida Lazzez Tullia Gallina Toschi Mohamed Bouaziz 《Journal of the American Oil Chemists' Society》2017,94(3):435-447
Phenolics, volatiles, squalene, tocopherols, and fatty acids of virgin olive oils (VOO) from adult and young olive trees of the Oueslati variety, typically cultivated in the Center of Tunisia, were analyzed at three different harvesting periods. Significant differences in contents of saturated fatty acids (p < 0.05), squalene (p < 0.05), alpha-tocopherol and total tocopherol (p < 0.02) and oxidized form of decarboxymethyl oleuropein aglycon (p < 0.05) were seen between VOO from adult and young trees during maturation. Moreover, the volatile profiles of VOO from adult and young trees showed significant differences in the amounts of hexanal, 1-penten-3-ol (p < 0.05), (Z)-3-hexenal and (Z)-2-penten-1-ol (p < 0.01). Principal component analysis showed that olives from adult trees should be harvested at the cherry stage of maturation to obtain a satisfactory level of oil quality, while olives from young trees should be harvested at the black maturation stage. 相似文献
97.
Susana Lpez-Ortiz Jose Pinto-Fraga Pedro L. Valenzuela Juan Martín-Hernndez María M. Seisdedos Oscar García-Lpez Nicola Toschi Francesca Di Giuliano Francesco Garaci Nicola Biagio Mercuri Robert Nistic Enzo Emanuele Simone Lista Alejandro Lucia Alejandro Santos-Lozano 《International journal of molecular sciences》2021,22(6)
Alzheimer’s disease (AD), the most common form of neurodegenerative dementia in adults worldwide, is a multifactorial and heterogeneous disorder characterized by the interaction of genetic and epigenetic factors and the dysregulation of numerous intracellular signaling and cellular/molecular pathways. The introduction of the systems biology framework is revolutionizing the study of complex diseases by allowing the identification and integration of cellular/molecular pathways and networks of interaction. Here, we reviewed the relationship between physical activity and the next pathophysiological processes involved in the risk of developing AD, based on some crucial molecular pathways and biological process dysregulated in AD: (1) Immune system and inflammation; (2) Endothelial function and cerebrovascular insufficiency; (3) Apoptosis and cell death; (4) Intercellular communication; (5) Metabolism, oxidative stress and neurotoxicity; (6) DNA damage and repair; (7) Cytoskeleton and membrane proteins; (8) Synaptic plasticity. Moreover, we highlighted the increasingly relevant role played by advanced neuroimaging technologies, including structural/functional magnetic resonance imaging, diffusion tensor imaging, and arterial spin labelling, in exploring the link between AD and physical exercise. Regular physical exercise seems to have a protective effect against AD by inhibiting different pathophysiological molecular pathways implicated in AD. 相似文献
98.
99.
A.E.C. Antunes A.T. Silva e Alves D.A. Gallina F.K.H.S. Trento P.B. Zacarchenco A.G.F. Van Dender I. Moreno R.C.S.C. Ormenese L.M. Spadoti 《Journal of dairy science》2014
The segment of the world population showing permanent or temporary lactose intolerance is quite significant. Because milk is a widely consumed food with an high nutritional value, technological alternatives have been sought to overcome this dilemma. Microfiltration combined with pasteurization can not only extend the shelf life of milk but can also maintain the sensory, functional, and nutritional properties of the product. This studied developed a pasteurized, microfiltered, lactose hydrolyzed (delactosed) skim milk (PMLHSM). Hydrolysis was performed using β-galactosidase at a concentration of 0.4 mL/L and incubation for approximately 21 h at 10 ± 1°C. During these procedures, the degree of hydrolysis obtained (>90%) was accompanied by evaluation of freezing point depression, and the remaining quantity of lactose was confirmed by HPLC. Milk was processed using a microfiltration pilot unit equipped with uniform transmembrane pressure (UTP) ceramic membranes with a mean pore size of 1.4 μm and UTP of 60 kPa. The product was submitted to physicochemical, microbiological, and sensory evaluations, and its shelf life was estimated. Microfiltration reduced the aerobic mesophilic count by more than 4 log cycles. We were able to produce high-quality PMLHSM with a shelf life of 21 to 27 d when stored at 5 ± 1°C in terms of sensory analysis and proteolysis index and a shelf life of 50 d in regard to total aerobic mesophile count and titratable acidity. 相似文献
100.
Why Tyrosol Derivatives Have to Be Quantified in the Calculation of “Olive Oil Polyphenols” Content to Support the Health Claim Provisioned in the EC Reg. 432/2012 下载免费PDF全文
Maria Z. Tsimidou Nikolaos Nenadis Maurizio Servili Diego Luis García‐González Tullia Gallina Toschi 《European Journal of Lipid Science and Technology》2018,120(6)
The viewpoint is the outcome of the scientific expertise of the scientists that sign it and work collaboratively in the frame of the OLEUM project. The project aims to better guarantee olive oil quality and authenticity by empowering detection and fostering prevention of olive oil fraud and by an effort of harmonization, correct interpretation, and use of official and supporting analytical methods. Practical Applications: The consensus among scientists, the European food authorities, IOC, and the olive industry on which compounds should be determined to support the health claim on olive oil polyphenols (EC Reg. 432/2012) is of utmost importance and can be supported by the evidence provided in this viewpoint article. The exact interpretation of this health claim involves the clarification of the compounds that should be summed up to give the amount of at least 5 mg phenols per 20 g of oil. 相似文献