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Sebastiano Di Pietro Dalila Iacopini Aldo Moscardini Ranieri Bizzarri Mauro Pineschi Valeria Di Bussolo Giovanni Signore 《Molecules (Basel, Switzerland)》2021,26(5)
Europium (III) luminescent chelates possess intrinsic photophysical properties that are extremely useful in a wide range of applications. The lack of examples of coumarin-based lanthanide complexes is mainly due to poor photo-sensitization attempts. However, with the appeal of using such a versatile scaffold as antenna, especially in the development of responsive molecular probes, it is worth the effort to research new structural motifs. In this work, we present a series of two new tris coumarin-dipicolinate europium (III) complexes, specifically tailored to be either a mono or a dual emitter, tuning their properties with a simple chemical modification. We also encountered a rich chemical speciation in solution, studied in detail by means of paramagnetic NMR and emission spectroscopy. 相似文献
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Dalila Azzam-Laouir Wafiya Boukrouk 《Numerical Functional Analysis & Optimization》2013,34(6):704-729
In this article, we study a second-order differential equation with three-point boundary conditions with the notion of Hukuhara derivatives. The existence and uniqueness of a solution is given under a Lipschitz condition on the right-hand side in the second and third variables. 相似文献
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Khadija El Ouahdani Imane Es-safi Hamza Mechchate Mohammed Al-zahrani Ashraf Ahmed Qurtam Mohammed Aleissa Amina Bari Dalila Bousta 《Molecules (Basel, Switzerland)》2021,26(22)
The study of bioactive molecules of natural origin is a focus of current research. Thymus algeriensis and Artemisia herba-alba are two medicinal plants widely used by the Moroccan population in the traditional treatment of several pathologies linked to inflammation. This study aimed to evaluate the single and combined antioxidant, anti-inflammatory and analgesic effects of the essential oils extracted from these two medicinal plants, and also their potential toxicity. Essential oils were extracted using hydro-distillation in a Clevenger-type apparatus. The antioxidant activity was evaluated by two methods: the scavenging of the free radical DPPH, and the reduction in iron. Anti-inflammatory activity was evaluated by evaluating the edema development induced by carrageenan injecting, while the analgesic power was evaluated according to the number of abdominal contortions induced by the intraperitoneal injection of acetic acid (0.7%). The acute oral toxicity was performed to assess the potential toxicity of the studied EOs, followed by an analysis of the blood biochemical parameters. The results of the two antioxidant tests indicated that our extract mixture exhibits good iron reduction capacity and very interesting DPPH free radical scavenging power, with an IC50 of around 4.38 ± 0.98 μg/mL higher than that of the benchmark antioxidant, BHT. The anti-inflammatory test demonstrated that the mixture administered orally at a dose of 150 mg/kg has a better activity, exceeding that of 1% Diclofenac, with a percentage of maximum inhibition of the edema of 89.99 ± 4.08. The number of cramps in the mice treated with the mixture at a dose of 150 mg/kg is significantly lower (29.80 ± 1.92) than those of the group treated with Tramadol (42.00 ± 2.70), respectively. The toxicity results show no signs of toxicity with an LD50 greater than 150 mg/Kg. These interesting results show that the two plants’ EOs had an important anti-inflammatory, analgesic, and antioxidant activity, and also a powerful synergistic effect, which encourages further in-depth investigations on their pharmacological proprieties. 相似文献
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Dalila B. M. M. Fontes Eleni Hadjiconstantinou Nicos Christofides 《Journal of Global Optimization》2006,34(1):127-155
In this paper a Branch-and-Bound (BB) algorithm is developed to obtain an optimal solution to the single source uncapacitated
minimum cost Network Flow Problem (NFP) with general concave costs. Concave NFPs are NP-Hard, even for the simplest version therefore, there is a scarcity of exact methods to address them in their full generality.
The BB algorithm presented here can be used to solve optimally single source uncapacitated minimum cost NFPs with any kind
of concave arc costs. The bounding is based on the computation of lower bounds derived from state space relaxations of a dynamic
programming formulation. The relaxations, which are the subject of the paper (Fontes et al., 2005b) and also briefly discussed
here, involve the use of non-injective mapping functions, which guarantee a reduction on the cardinality of the state space.
Branching is performed by either fixing an arc as part of the final solution or by removing it from the final solution. Computational
results are reported and compared to available alternative methods for addressing the same type of problems. It could be concluded
that our BB algorithm has better performance and the results have also shown evidence that it has a sub-exponential time growth. 相似文献
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