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排序方式： 共有1443条查询结果，搜索用时 15 毫秒
41.
Gabriela del C Robles-Flores Miguel Abud-Archila Lucía María C. Ventura-Canseco Rocío Meza-Gordillo Alicia Grajales-Lagunes Miguel A. Ruiz-Cabrera Federico A. Gutiérrez-Miceli 《Food and Bioprocess Technology》2018,11(12):2172-2181
The aim of this work was to develop and evaluate the effect of an edible coating produced with protein isolate and gum from the Cajanus cajan seed to be applied to strawberries (Fragaria spp.). The films were formulated using 1 and 2% gum, and 5 and 10% protein isolate, as well as glycerol (2%) as a plasticizer. The formulated films were evaluated in terms of water vapor permeability (WVP), opacity, color, scanning electron microscopy, and texture. Once the ideal formulation with sufficiently low WVP and opacity was selected, it was applied to the strawberries, which were evaluated in terms of mass loss, color, firmness, acidity, pH, soluble solids, anthocyanin content, vitamin C content, and acceptability degree by an untrained consumer panel. Results showed that film made from 5% of protein isolate and 1% of gum had the lowest WVP of all treatments. Applied to strawberries, the coating resulted in a reduction of the total soluble solid content, the consumption of citric acid, and the mass loss of coated with respect to uncoated strawberries after 10 days of storage at 5 °C, without causing sensorial changes. 相似文献
42.
Simona Sestito;Roberta Ibba;Federico Riu;Sara Carpi;Antonio Carta;Clementina Manera;Solomon Habtemariam;Balakyz Yeskaliyeva;Zainab M. Almarhoon;Javad Sharifi-Rad;Simona Rapposelli; 《Food Science & Nutrition》2024,12(10):6970-6989
Many naturally derived compounds are currently used in oncotherapy. Besides official medicine, complementary and alternative medicine practices, including old herbal remedies, are widely used and accepted as additional tools in cancer treatment. Angelica gigas Nakai (AGN), a medicinal herb in Asia, has roots historically used in medicine. This review focuses on key bioactive compounds from AGN roots – decursin, decursinol angelate (DA), and decursinol (DOH). Exploring their source, biosynthesis, and therapeutic mechanisms, the review highlights their role in cancer treatment. Biotechnological strategies for enhanced production and semisynthetic derivatives with anticancer properties are discussed. The study emphasizes the promising pharmacological potential of decursin, DA, and DOH in various therapeutic applications, particularly cancer treatment. The review also underscores innovative approaches to increase production and explores semisynthetic derivatives as a promising avenue for future natural product-based drug discovery. This concise overview provides valuable insights into the potential of AGN-derived compounds in the field of natural product-based therapeutics. 相似文献
43.
Nils‐Jrgen Knudsen Dal Agnese Kocere Jens Wohlmann Simon Van Herck Tobias A. Bauer Julien Resseguier Shahla Bagherifam Hilde Hyldmo Matthias Barz Bruno G. De Geest Federico Fenaroli 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(5)
The zebrafish embryo is a vertebrate well suited for visualizing nanoparticles at high resolution in live animals. Its optical transparency and genetic versatility allow noninvasive, real‐time observations of vascular flow of nanoparticles and their interactions with cells throughout the body. As a consequence, this system enables the acquisition of quantitative data that are difficult to obtain in rodents. Until now, a few studies using the zebrafish model have only described semiquantitative results on key nanoparticle parameters. Here, a MACRO dedicated to automated quantitative methods is described for analyzing important parameters of nanoparticle behavior, such as circulation time and interactions with key target cells, macrophages, and endothelial cells. Direct comparison of four nanoparticle (NP) formulations in zebrafish embryos and mice reveals that data obtained in zebrafish can be used to predict NPs' behavior in the mouse model. NPs having long or short blood circulation in rodents behave similarly in the zebrafish embryo, with low circulation times being a consequence of NP uptake into macrophages or endothelial cells. It is proposed that the zebrafish embryo has the potential to become an important intermediate screening system for nanoparticle research to bridge the gap between cell culture studies and preclinical rodent models such as the mouse. 相似文献
44.
Jacopo Stefano Pelli Cresi Francesco Carl Raja Znaiguia Helena Isern Francesco Benedetti Gabriele Gasperi Lucia Amidani Sergio Valeri Federico Boscherini Paola Luches 《Advanced Materials Interfaces》2020,7(18)
To optimize the catalytic functionality of cerium oxide it is important to understand the structural modifications associated with reduction and the role of the proximity of metals, which are often coupled with the oxide in the applications. For this purpose, the evolution of the short‐ and long‐range structure of cerium oxide ultrathin epitaxial films and nanostructures supported on Pt(111) is investigated using X‐ray absorption spectroscopy at the Ce L3 edge and surface X‐ray diffraction, during reduction by thermal treatments in vacuum. In epitaxial nanoislands reduction is associated with a contraction of the Ce–O distance and with the appearance of Ce Pt bonds. The formation of a phase with a (2 × 2) periodicity after a thermal treatment at 1023 K is ascribed to the formation of a Pt5Ce alloy. Films of 3 nm thickness do not show, on average, significant structural modifications with the same thermal treatment, consistent with the hypothesis that the reduction involves only the topmost surface layers and it does not influence significantly the bulk structure of the material. This study demonstrates a strong interaction between cerium oxide and platinum, which has implications for the reactivity and stability of catalysts based on metals combined with reducible oxides. 相似文献
45.
46.
Federico Ciardo Brice Lecampion François Fayard Stéphanie Chaillat 《International journal for numerical methods in engineering》2020,121(24):5696-5718
We present a numerical method for the solution of nonlinear geomechanical problems involving localized deformation along shear bands and fractures. We leverage the boundary element method to solve for the quasi-static elastic deformation of the medium while rigid-plastic constitutive relations govern the behavior of displacement discontinuity (DD) segments capturing localized deformations. A fully implicit scheme is developed using a hierarchical approximation of the boundary element matrix. Combined with an adequate block preconditioner, this allows to tackle large problems via the use of an iterative solver for the solution of the tangent system. Several two-dimensional examples of the initiation and growth of shear-bands and tensile fractures illustrate the capabilities and accuracy of this technique. The method does not exhibit any mesh dependency associated with localization provided that (i) the softening length-scale is resolved and (ii) the plane of localized deformations is discretized a priori using DD segments. 相似文献
47.
Gianluca Milano Federico Ferrarese Lupi Matteo Fretto Carlo Ricciardi Natascia De Leo Luca Boarino 《Advanced Quantum Technologies》2020,3(5)
As a consequence of the redefinition of the International System of Units (SI), where units are defined in terms of fundamental physical constants, memristive devices represent a promising platform for quantum metrology. Coupling ionics with electronics, memristive devices can exhibit conductance levels quantized in multiples of the fundamental quantum of conductance G0 = 2e2/h. Since the fundamental quantum of conductance G0 is related only to physical constants that assume fixed value in the revised SI, memristive devices can be exploited for the practical realization of a quantum‐based resistance standard that, differently from quantum‐Hall based devices conventionally adopted as resistance standards, can operate in different ambient conditions (air, vacuum, harsh environment), in a wide range of temperatures and without the need of an applied magnetic field. In this work, the possibility of using memristive devices for quantum metrology is critically discussed, based on recent experimental and theoretical advances on quantum conductance phenomena reported in literature. Thanks to the high operational speed, high scalability down to the nanometer scale, and CMOS compatibility, memristive devices allow on‐chip implementation of a resistance standard required for the realization of self‐calibrating electrical systems and equipment with zero‐chain traceability in accordance with the revised SI. 相似文献
48.
Chenglin Yan Haiguang Zhao Dmitrii F. Perepichka Federico Rosei 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(29):3888-3907
Lanthanide doped upconverting nanoparticles (UCNPs) have emerged as a new class of luminescent materials, with major discoveries and overall significant progress during the last decade. Unlike multiphoton absorption in organic dyes or semiconductor quantum dots, lanthanide doped UCNPs involve real intermediate quantum states and convert infrared (IR) into visible light via sequential electronic excitation. The relatively high efficiency of this process even at low radiation flux makes UCNPs particularly attractive for many current and emerging areas of technology. The aim of this article is to highlight several recent advances in this rapidly growing field, emphasizing the relationships between structure and properties of UCNPs. Additionally, various strategies developed for the synthesis of UCNPs with a focus on the various synthetic approaches that yield high‐quality monodisperse samples with controlled size, shape and crystalline phase are reviewed. Emerging synthetic approaches towards designed structure to improve the optical and electronic properties of UCNPs are discussed. Finally, recent examples of applications of UCNPs in biomedical and optoelectronics research, giving our own perspectives on future directions and emerging possibilities of the field are described. 相似文献
49.
Federico Najson 《International journal of control》2016,89(4):770-782
The present communication is concerned with uniform exponential stability, under arbitrary switching, in discrete-time switched positive linear systems. Lagrange duality is used in order to obtain a new characterisation for uniform exponential stability which is in terms of sets of inequalities involving each of the matrices that represent the modes of the system. These sets of inequalities are shown to generalise the classical linear Lyapunov inequality that characterises, in positive matrices, the property of being Schur. Each solution to these sets of inequalities is shown to provide a representation, in terms of a number of linear functionals, for a common Lyapunov function for the switched positive linear system. A result is further presented which conveys to, a conservative upper bound on the minimum required number of linear functionals (in the above mentioned representation), and also to a method for computing them. Our proof for the aforementioned characterisation is based on another (equivalent) characterisation, in terms of the solvability of a dynamic programming equation associated to the switched positive linear system, which is also reported in the paper. In particular, it is shown that the associated dynamic programming equation has at most one solution. And this solution is shown to be convex, monotonic, positively homogeneous, and it yields a common Lyapunov function for the switched positive linear system. 相似文献
50.
Marzia Ognibene Patrizia De Marco Stefano Parodi Mariaclaudia Meli Andrea Di Cataldo Federico Zara Annalisa Pezzolo 《International journal of molecular sciences》2022,23(12)
Neuroblastoma (NB) is a tumor of the developing sympathetic nervous system. Despite recent advances in understanding the complexity of NB, the mechanisms that determine its regression or progression are still largely unknown. Stage 4S NB is characterized by a favorable course of disease and often by spontaneous regression, while progression to true stage 4 is a very rare event. Here, we focused on genomic analysis of an NB case that progressed from stage 4S to stage 4 with a very poor outcome. Array-comparative genomic hybridization (a-CGH) on tumor-tissue DNA, and whole-exome sequencing (WES) on exosomes DNA derived from plasma collected at the onset and at the tumor progression, pointed out relevant genetic changes that can explain this clinical worsening. The combination of a-CGH and WES data allowed for the identification iof somatic copy number aberrations and single-nucleotide variants in genes known to be responsible for aggressive NB. KLRB1, MAPK3 and FANCA genes, which were lost at the time of progression, were studied for their possible role in this event by analyzing in silico the impact of their expression on the outcome of 786 NB patients. 相似文献