Alternative Representations for Codifying Solutions in Permutation-Based Problems

Since their introduction, Estimation of Distribution Algorithms (EDAs) have proved to be very competitive algorithms to solve many optimization problems. However, despite recent developments, in the case of permutation-based combinatorial optimization problems, there are still many aspects that deserve further research. One of them is the influence of the codification employed to represent the solutions on the overall performance of the algorithm. When considering classical EDAs, optimizing permutation problems is challenging, and specific mechanisms are needed to hold the restrictions associated with the permutation nature of solutions.In this paper, in addition to the permutation-vector codification, we investigate alternative representations to describe solutions of permutation problems in the context of EDAs. In order to evaluate their influence, we adopted a classical EDA and conducted an experimental study on two different permutation problems and representations for codifying solutions. The results revealed a narrow relationship between the type of combinatorial problem optimized and the selected representation used to codify its solutions. Moreover, the results point out that choosing the appropriate representation to codify solutions of the given permutation problem is critical for the performance of the algorithm

Linear differential equations with finite differential Galois group

For a finite irreducible subgroup H⊂PSL(Cn) and an irreducible, H-invariant curve Z⊂P(Cn) such that C(Z)H=C(t), a standard differential operator Lst∈C(t)[d/dt] is constructed. For n=2 this is essentially Klein's work. For n>2 an actual calculation of Lst is done by computing an evaluation of invariants C[X1,…,Xn]H→C(t) and applying a scalar form of a theorem of E. Compoint in a “Procedure”. Also in some cases where Z is unknown evaluations are produced. This new method is tested for n=2 and for three irreducible subgroups of SL3. This supplements [18]. The theory developed here relates to and continues classical work of H.A. Schwarz, G. Fano, F. Klein and A. Hurwitz

A resorcinarene for inhibition of Aβ fibrillation.

Amyloid-β peptides (Aβ) fibrillation is the hallmark of Alzheimer's disease (AD). However, it has been challenging to discover potent agents in order to inhibit Aβ fibrillation. Herein, we demonstrated the effect of resorcinarene on inhibiting Aβ fibrillation in vitro via experimental and computational methods. Aβ were incubated with different concentrations of resorcinarene so as to monitor the kinetics by using thioflavin T binding assay. The results, which were further confirmed by far-UV CD spectroscopy and atomic force microscopy, strongly indicated that the higher concentration of resorcinarene, the more effective the inhibition of Aβ fibrillation. A cytotoxicity study showed that when sea urchin embryos were exposed to the resorcinarene, the majority survived due to the resorcinarene low toxicity. In addition, when the resorcinarene was added, the formation of toxic Aβ 42 species was delayed. Computational studies of Aβ fibrillation, including docking simulations and MD simulations, illustrated that the interaction between inhibitor resorcinarene and Aβ is driven by the non-polar interactions. These studies display a novel strategy for the exploration of promising antiamyloiddogenic agents for AD treatments

From environment to clinic: the role of pesticides in antimicrobial resistance

La resistencia a los antimicrobianos (RAM) en los agentes patógenos ha sido relacionada principalmente con el uso excesivo de los antibióticos. La mayoría de los estudios sobre la resistencia se han centrado en los agentes patógenos de importancia clínica; sin embargo, los microorganismos están expuestos a numerosas sustancias antropogénicas. Son muy pocos los estudios dedicados a determinar los efectos que producen las sustancias químicas en los microorganismos. La exposición a estas sustancias puede contribuir a los niveles mayores de la RAM. Comprender las comunidades de microorganismos en el medioambiente natural y los mecanismos de la RAM por los efectos de las sustancias antropogénicas, como los plaguicidas, resulta importante para abordar la actual crisis de la resistencia a los antimicrobianos. En este informe se hace énfasis en las moléculas, en lugar de los antibióticos, que se usan generalmente en los productos agroquímicos y que podrían contribuir a que se desarrolle la RAM en entornos no clínicos, como el suelo. Asimismo, se analiza el papel de los plaguicidas como mediadores en la aparición de la RAM, así como la manera en la que los genes y los microorganismos resistentes a los antibióticos se trasladan hacia el entorno antrópico. La evidencia indica que el entorno natural podría ser una vía clave de propagación para los genes resistentes a los antibióticos. Comprender la interrelación entre el suelo, el agua y los plaguicidas es fundamental para crear consciencia en cuanto a la necesidad de establecer programas de seguimiento ambiental y así poder superar la crisis actual de la RAM.Antimicrobial resistance (AMR) in pathogens has been associated mainly with excessive use of antibiotics. Most studies of resistance have focused on clinical pathogens; however, microorganisms are exposed to numerous anthropogenic substances. Few studies have sought to determine the effects of chemical substances on microorganisms. Exposure to these substances may contribute to increased rates of AMR. Understanding microorganism communities in natural environments and AMR mechanisms under the effects of anthropogenic substances, such as pesticides, is important to addressing the current crisis of antimicrobial resistance. This report draws attention to molecules, rather than antibiotics, that are commonly used in agrochemicals and may be involved in developing AMR in non-clinical environments, such as soil. This report examines pesticides as mediators for the appearance of AMR, and as a route for antibiotic resistance genes and antimicrobial resistant bacteria to the anthropic environment. Available evidence suggests that the natural environment may be a key dissemination route for antibiotic-resistant genes. Understanding the interrelationship of soil, water, and pesticides is fundamental to raising awareness of the need for environmental monitoring programs and overcoming the current crisis of AMR

P4-NetFPGA-based network slicing solution for 5G MEC architectures

Network Slicing is one of the fundamental capabilities of the new Fifth-generation (5G)networks. It is defined as several logical networks that are created to fulfil specific Quality of Service (QoS)and Quality of Experience (QoE)requirements and are available over the same physical infrastructure. This paper proposes a novel extension to P4-NetFPGA framework to achieve network slicing between different 5G users in the edge-to-core network segment. This solution provides hardware-isolation of the performance in terms of bandwidth, latency and packet loss of 5G network traffic. The work proposed has been validated in a real 5G infrastructure

Una perspectiva fenomenológica para la enseñanza del Electromagnetismo a nivel introductorio

The student's lack of knowledge about a phenomenology which could be the object of study is one of the problems encountered in teaching the electromagnetic theory. The construction and B first approzimation to a characterization of this phenomenology is used as an strategy to allow the student to start the elaboration of the basic electromagnetic 's theory concepts. The process is carry out around three problems: the electrification by friction phenomena (static electricity), electric current and its relation with the static electricity, and the  lectromagnetic phenomena.</p

Resistin Regulates Pituitary Lipid Metabolism and Inflammation In Vivo

The adipokine resistin is an insulin-antagonizing factor that also plays a regulatory role in inflammation, immunity, food intake, and gonadal function and also regulates growth hormone (GH) secretion in rat adenopituitary cells cultures with the adipokine. Although adipose tissue is the primary source of resistin, it is also expressed in other tissues, including the pituitary. The aim of this study is to investigate the possible action of resistin on the lipid metabolism in the pituitary gland in vivo (rats in two different nutritional status, fed and fast, treated with resistin on acute and a chronic way) and in vitro (adenopituitary cell cultures treated with the adipokine). Here, by a combination of in vivo and in vitro experimental models, we demonstrated that central acute and chronic administration of resistin enhance mRNA levels of the lipid metabolic enzymes which participated on lipolysis and moreover inhibiting mRNA levels of the lipid metabolic enzymes involved in lipogenesis. Taken together, our results demonstrate for the first time that resistin has a regulatory role on lipid metabolism in the pituitary gland providing a novel insight in relation to the mechanism by which this adipokine can participate in the integrated control of lipid metabolism