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31.
Marcelo Medeiros Pinheiro Rozana Mesquita Ciconelli Gabriela Villaça Chaves Luana Aquino Claudia Ridel Juzwiak Patrícia de Souza Genaro Marcos Bosi Ferraz 《Nutrition journal》2011,10(1):39
Background
Antioxidant nutrient intake and the lesser formation of free radicals seem to contribute to chronic diseases. The aim of the present study was to evaluate the intake profile of the main dietary antioxidants in a representative sample of the adult Brazilian population and discuss the main consequences of a low intake of these micronutrients on overall health. 相似文献32.
Luana Carvalho de Oliveira Danielle Lima Bezerra de Menezes Valria Costa da Silva Estela Mariana Guimares Loureno Paulo Henrique Santana Miranda Mrcia de Jesus Amazonas da Silva Emerson Silva Lima Valdir Florêncio da Veiga Júnior Ricardo Neves Marreto Attilio Converti Euzbio Guimaraes Barbosa dley Antonini Neves de Lima 《International journal of molecular sciences》2021,22(18)
α,β-amyrenone (ABAME) is a triterpene derivative with many biological activities; however, its potential pharmacological use is hindered by its low solubility in water. In this context, the present work aimed to develop inclusion complexes (ICs) of ABAME with γ- and β-cyclodextrins (CD), which were systematically characterized through molecular modeling studies as well as FTIR, XRD, DSC, TGA, and SEM analyses. In vitro analyses of lipase activity were performed to evaluate possible anti-obesity properties. Molecular modeling studies indicated that the CD:ABAME ICs prepared at a 2:1 molar ratio would be more stable to the complexation process than those prepared at a 1:1 molar ratio. The physicochemical characterization showed strong evidence that corroborates with the in silico results, and the formation of ICs with CD was capable of inducing changes in ABAME physicochemical properties. ICs was shown to be a stronger inhibitor of lipase activity than Orlistat and to potentiate the inhibitory effects of ABAME on porcine pancreatic enzymes. In conclusion, a new pharmaceutical preparation with potentially improved physicochemical characteristics and inhibitory activity toward lipases was developed in this study, which could prove to be a promising ingredient for future formulations. 相似文献
33.
Luana Beatriz dos Santos Nascimento Massimiliano Tattini 《International journal of molecular sciences》2022,23(9)
Plants evolved an impressive arsenal of multifunctional specialized metabolites to cope with the novel environmental pressures imposed by the terrestrial habitat when moving from water. Here we examine the multifarious roles of flavonoids in plant terrestrialization. We reason on the environmental drivers, other than the increase in UV-B radiation, that were mostly responsible for the rise of flavonoid metabolism and how flavonoids helped plants in land conquest. We are reasonably based on a nutrient-deficiency hypothesis for the replacement of mycosporine-like amino acids, typical of streptophytic algae, with the flavonoid metabolism during the water-to-land transition. We suggest that flavonoids modulated auxin transport and signaling and promoted the symbiosis between plants and fungi (e.g., arbuscular mycorrhizal, AM), a central event for the conquest of land by plants. AM improved the ability of early plants to take up nutrients and water from highly impoverished soils. We offer evidence that flavonoids equipped early land plants with highly versatile “defense compounds”, essential for the new set of abiotic and biotic stressors imposed by the terrestrial environment. We conclude that flavonoids have been multifunctional since the appearance of plants on land, not only acting as UV filters but especially improving both nutrient acquisition and biotic stress defense. 相似文献
34.
Luana De Lucca de Costa Alberto Moreira Guerreiro Brito Andr Rosiak Lirio Schaeffer 《The International Journal of Advanced Manufacturing Technology》2020,107(1):39-47
Low boron steels are the only class of steel capable of forming a fully martensitic microstructure after hot stamping when a cooled tool is used, and the m 相似文献
35.
Luana Roleto Cardoso Flvia Emi Razera Baldasso Dbora Delai Francisco Montagner Patrícia Maria Poli Kopper 《Microscopy research and technique》2019,82(2):128-133
This study evaluated the influence of canal irrigation protocols with 5.25% calcium hypochlorite [Ca(OCl)2], 5.25% sodium hypochlorite (NaOCl) and 17% EDTA solution on the inorganic component of root canal dentin. Sixty roots were randomly divided into six groups (n = 10): Saline solution (SS) (control); Saline solution (SSE) +17% EDTA; CH ? 5.25% Ca(OCl)2; CHE ? 5.25% Ca(OCl)2 + 17% EDTA; SH ? 5.25% NaOCl; SHE ? 5.25% NaOCl +17% EDTA. After canal irrigation, the specimens were longitudinally split and analyzed by scanning electron microscopy (SEM). Dentinal tubules were observed in transverse (middle and apical thirds) direction. The images were classified in scores, according to smear layer removal and peritubular dentin alteration, and data were analyzed by Kruskal–Wallis's test, followed by Dunn's test (α = 0.05). In the middle third, all groups with EDTA presented better removal of the smear layer with higher peritubular dentin alteration (p < .05). In the apical third, this happened only in SHE (p < .05). Ca(OCl)2 and NaOCl exhibit similar performance to remove smear layer and alteration of the inorganic component in the middle third. In the apical third, NaOCl associated with EDTA showed better performance in smear layer removal. 相似文献
36.
The flat-band voltage of PdSi3N4SiO2Si MOS structures has been measured at room temperature as a function of the time after the exposure of the devices to an atmosphere; the hydrogen (deuterium) partial pressure was in the range 5–60 Pa. The experimental flat-band transients well agree with the analytical ones obtained from an extension to the transitory case of the induced dipole model. This fact confirms the validity of the model and allows us to investigate the behaviour of the transient parameters as a function of the H2 (D2) partial pressure. 相似文献
37.
Bagnoli P.E. Casarosa C. Dallago E. Nardoni M. 《Power Electronics, IEEE Transactions on》1998,13(6):1220-1228
For pt.I see ibid., vol.13, no.6, p.1208-19 (1998). The TRAIT method for thermal characterization of electronic devices, whose theory was exposed in part I for one-dimensional (1-D) structures, was here applied to systems having heat fluxes with three-dimensional (3-D) dependence in order to demonstrate that the spatial resolution of the thermal resistance analysis is still qualitatively maintained in this type of structure too. The analytical procedure was first applied to simulated structures whose temperature transients and steady-state fields were obtained by means of a finite-element thermal simulation program. In these cases, the knowledge of the steady-state temperature distribution allowed identifying the thermal physical domains which correspond to the cells of the calculated equivalent thermal circuit composed by resistances and capacitances. Furthermore, some experiments on real electronic devices with purposely designed assembling structures were exposed and discussed. The samples were power-integrated circuits with plastic packages mounted on various substrates and Schottky diodes in TO-3 packages. The experiments on both simulated and real devices demonstrated that TRAIT analysis, being able to recognize the localization of some induced defects, maintains its spatial resolution character, despite the large distortion of the thermal domains occurring when the defects are close to the heat source 相似文献
38.
An important question to be addressed regarding system control on a time interval [0, T] is whether some particular target state in the configuration space is reachable from a given initial state. When the target of interest refers only to a portion of the spatial domain, we speak about regional analysis. Cellular automata approach have been recently promoted for the study of control problems on spatially extended systems for which the classical approaches cannot be used. An interesting problem concerns the situation where the subregion of interest is not interior to the domain but a portion of its boundary . In this paper we address the problem of regional controllability of cellular automata via boundary actions, i.e., we investigate the characteristics of a cellular automaton so that it can be controlled inside a given region only acting on the value of sites at its boundaries. 相似文献
39.
Shear Piezoelectricity in Poly(vinylidenefluoride‐co‐trifluoroethylene): Full Piezotensor Coefficients by Molecular Modeling,Biaxial Transverse Response,and Use in Suspended Energy‐Harvesting Nanostructures
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40.
Natalia Cadavid Muñoz Luana Floriano Maiara P. de Souza Nelson M. G. Bandeira Osmar D. Prestes Renato Zanella 《Food Analytical Methods》2017,10(2):320-329
A fast and effective multiresidue method for the determination of 42 pesticides in golden berry was developed and validated. A modified QuEChERS method was established for sample preparation followed by ultra-high performance liquid chromatographic-tandem mass spectrometry (UHPLC-MS/MS) determination with electrospray ionization in a triple quadrupole system. Validation results were satisfactory, since the method presented recoveries between 70 and 114 % with relative standard deviations (RSD) <20 % for blank samples spiked from 5 to 25 μg kg?1. The method limit of detection and limit of quantification were 1.5 and 5 μg kg?1 , respectively. Matrix effect ranged from ?32 to 218 % and was compensated using matrix-matched calibration. Method linearity was established from 2.5 to 100 μg kg?1 with r 2 ≥ 0.99. The proposed method combines the advantages of a simple and fast sample preparation step by a modified QuEChERS method with the high selectivity and sensitivity of the UHPLC-MS/MS system using selected reaction monitoring. The method was successfully applied to commercial samples, proving to be an efficient alternative for routine analysis. From the 16 analyzed samples, 13 presented residues of one or more pesticides (carbendazim, chlorpyrifos ethyl, dimethoate, propamocarb, and tebuconazole) in the concentration range of 2.0 to 55.6 μg kg?1. 相似文献