Staphylococci are the main etiological agents of bovine mastitis. Bacteriocins and nanoparticles have emerged as promising alternatives for the future development of antimicrobial agents. This study ...evaluated the activity of the bacteriocin nisin and bicelles of the synthetic cationic lipid dioctadecyldimethylammonium bromide, alone and in combination, against multidrug-resistant Staphylococcus spp. strains isolated from bovine mastitis. In summary, cationic nisin/dioctadecyldimethylammonium bromide nanoparticles are shown to be a promising alternative for the control of mastitis caused by multidrug-resistant Staphylococcus spp.
The development of Pickering emulsions as ecologically correct stabilized with bio-based material by substituting synthetic petroleum-derived tensoactives assumed a very attractive level, ...representing the current guideline of the global market for homecare industry, food and beverage applications. In this wor, cellulose nanocrystals (CNCs), a hierarchically advanced biomaterial, were produced to stabilize innovative emulsions formulated with western soapberry
Sapindus saponaria
L. oil (SO). Besides, green surfactants (triterpene saponins extracted from
S. saponaria
L. pericarp; SAP) were also investigated to stabilize the oil/water interface. The synergistic combination between cellulose nanowhiskers and the bioactive glycosides has never been reported in the literature. Dynamic interfacial tensions of SAP and SO were firstly investigated, and their capacity to form a plastic membrane at oil/water interface was revealed. Response surface methodology (RSM) was employed to study the influence of the binary systems (CNC:SAP) on the stability of emulsified systems, such as size and zeta potential. In addition, a new calculation was proposed to determine the coverage of the oil droplets formed by the mixture of cellulose crystallites and natural surfactants. The optimal nanoemulsion composition was determined to be 60 w/w (%) of water, 23.905 w/w % of SO, 5 w/w % of CNC and 8.095 w/w% of SAP to produce of smallest droplet (165.1 nm) combined with higher zeta potential module (−46.7 mV). Results highlight the potential of
Sapindus
saponins and cellulose nanowhiskers for efficient producing label-friendly nanoemulsions applicable for drug, cosmeceutical or edible delivery systems.
Graphical abstract
In this paper we are considering a third-order three-point equation with nonhomogeneous conditions in the boundary. Using Krasnoselskii's Theorem and Leray-Schauder Alternative we provide existence ...results of positive solutions for this problem. Nontrivials examples are given and a numerical method is introduced.
ABSTRACT In this paper we are considering a third-order three-point equation with nonhomogeneous conditions in the boundary. Using Krasnoselskii’s Theorem and Leray-Schauder Alternative we provide ...existence results of positive solutions for this problem. Nontrivials examples are given and a numerical method is introduced.
A nonlinear boundary value problem related to an equation of Kirchhoff is considered. The existence of positive solutions is proved through alternative Leray–Schauder’s type combined with ...Krasnoselskii’s fixed point theorem. Numerical methods are presented and a result of local convergence is established.
Outer Trust-Region Method for Constrained Optimization Birgin, Ernesto G.; Castelani, Emerson V.; Martinez, André L. M. ...
Journal of optimization theory and applications,
07/2011, Letnik:
150, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Given an algorithm
A
for solving some mathematical problem based on the iterative solution of simpler subproblems, an
outer trust-region
(OTR) modification of
A
is the result of adding a trust-region ...constraint to each subproblem. The trust-region size is adaptively updated according to the behavior of crucial variables. The new subproblems should not be more complex than the original ones, and the convergence properties of the OTR algorithm should be the same as those of Algorithm
A
. In the present work, the OTR approach is exploited in connection with the “greediness phenomenon” of nonlinear programming. Convergence results for an OTR version of an augmented Lagrangian method for nonconvex constrained optimization are proved, and numerical experiments are presented.
When one solves Nonlinear Programming problems by means of algorithms that use merit criteria combining the objective function and penalty feasibility terms, a phenomenon called
greediness
may occur. ...Unconstrained minimizers attract the iterates at early stages of the calculations and, so, the penalty parameter needs to grow excessively, in such a way that ill-conditioning harms the overall convergence. In this paper a regularization approach is suggested to overcome this difficulty. An Augmented Lagrangian method is defined with the addition of a regularization term that inhibits the possibility that the iterates go far from a reference point. Convergence proofs and numerical examples are given.
We investigated whether healthy subjects with high (highs) and low (lows) hypnotizability scores differ in the ability to report the position of their right hand in the horizontal plane at the end ...of passive and active arm movements directed to lateral, intermediate and medial targets of the right hemispace under correct or incorrect visual feedback. Results showed that incorrect visual feedback increased the error in both groups. In lows, the error was similar after active and passive movements; in highs, it was lower for active than passive movements toward the medial position, but lower for passive than for active movements for the lateral one. The highs' error was significantly lower than the lows' one only for the active movements directed toward the medial hand position. Hypnotizability-related differences may be due to different role of efferent copies in highs and lows.
The focus of this paper is to address some classical results for a class of hypercomplex numbers. More specifically we present an extension of the Square of the Error Theorem and a Bessel inequality ...for octonions.
We study a second order differential equation with nonlinear multi-point boundary conditions. The existence and multiplicity of positive solutions is proved through Krasnoselskii fixed point theorem ...and Avery-Peterson theorem.
PDF
