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201.
Mathematical Programming - The purpose of this paper is to characterize the weak efficient solutions, the efficient solutions, and the isolated efficient solutions of a given vector optimization...  相似文献   
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We find out upper bounds for the first eigenvalue of the stability operator for compact constant mean curvature orientable surfaces immersed in a Riemannian Killing submersion. As a consequence, the strong stability of such surfaces is studied. We also characterize constant mean curvature Hopf tori as the only ones attaining the bound in certain cases.  相似文献   
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Thermography is a tool used in many scientific disciplines, including agriculture. This paper describes the application of thermography as a rapid diagnostic method of adequate watering. Two experiments were conducted. In experiment 1, Philodendron erubescens and Anthurium andraeum were transplanted to pots in a greenhouse in Almeria (Spain). The vegetative growth parameters of these plants were measured. In experiment 2, two areas of vegetative cover were established on green walls: one with a combination of aromatic plants and another with ornamental indoor plants. The thermographic images were recorded using a compact infrared camera, which had a spectral infrared range of 7.3–13 μm, microbolometer of 320 × 240 pixels, and the resolution was 0.01 °C at 30 °C. Three irrigation treatments were applied in both experiments, consisting of a control treatment (CT), a deficit irrigation [1/3 less volume, deficient irrigation (DI)] treatment, and an excess irrigation [1/3 greater volume, excess irrigation (EI)] treatment. In both experiments, the sample temperatures were recorded by thermography for each irrigation treatment. In experiment 1, the vegetative growth parameters were greater under CT than under DI or EI. The data of the reference thermographs over the leaves of the potted plants were significantly correlated with the superior growth parameters under the optimal irrigation treatment. A continuous vegetative canopy was formed on both of the green walls in experiment 2, and the average temperatures were correlated with the irrigation treatments in this experiment. The temperatures reflected in the reference thermographs allowed for the determination of the most appropriate irrigation treatment. These results suggest that thermography can be a useful method to provide an early diagnosis of water stress in potted plants and green walls.  相似文献   
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Overuse and misuse of antibacterial drugs has resulted in bacteria resistance and in an increase in mortality rates due to bacterial infections. Therefore, there is an imperative necessity of new antibacterial drugs. Bio-organometallic derivatives of antibacterial agents offer an opportunity to discover new active antibacterial drugs. These compounds are well-characterized products and, in several examples, their antibacterial activities have been studied. Both inhibition of the antibacterial activity and strong increase in the antibiotic activity of the parent drug have been found. The synthesis of the main classes of bio-organometallic derivatives of these drugs, as well as examples of the use of structure–activity relation (SAR) studies to increase the activity and to understand the mode of action of bio-organometallic antimicrobial peptides (BOAMPs) and platensimicyn bio-organometallic mimics is presented in this article.  相似文献   
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Yorioka introduced a class of ideals (parametrized by reals) on the Cantor space to prove that the relation between the size of the continuum and the cofinality of the strong measure zero ideal on the real line cannot be decided in . We construct a matrix iteration of c.c.c. posets to force that, for many ideals in that class, their associated cardinal invariants (i.e., additivity, covering, uniformity and cofinality) are pairwise different. In addition, we show that, consistently, the additivity and cofinality of Yorioka ideals does not coincide with the additivity and cofinality (respectively) of the ideal of Lebesgue measure zero subsets of the real line.  相似文献   
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Alkoxylation and hydroxylation reactions of 1,5-cyclooctadiene (cod) in an iridium complex with alcohols and water promoted by the reduction of oxygen to hydrogen peroxide are described. The exo configuration of the OH/OR groups in the products agrees with nucleophilic attack at the external face of the olefin as the key step. The reactions also require the presence of a coordinating protic acid (such as picolinic acid (Hpic)) and involve the participation of a cationic diolefin iridium(III) complex, [Ir(cod)(pic)2]+, which has been isolated. Independently, this cation is also involved in easy alkoxy group exchange reactions, which are very unusual for organic ethers. DFT studies on the mechanism of olefin alkoxylation mediated by oxygen show a low-energy proton-coupled electron-transfer step connecting a superoxide–iridium(II) complex with hydroperoxide–iridium(III) intermediates, rather than peroxide complexes. Accordingly, a more complex reaction, with up to four different products, occurred upon reacting the diolefin–peroxide iridium(III) complex with Hpic. Moreover, such hydroperoxide intermediates are the origin of the regio- and stereoselectivity of the hydroxylation/alkoxylation reactions. If this protocol is applied to the diolefin–rhodium(I) complex [Rh(pic)(cod)], free alkyl ethers ORC8H11 (R=Me, Et) resulted, and the reaction is enantioselective if a chiral amino acid, such as l -proline, is used instead of Hpic.  相似文献   
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