Fuzzy synchronization of chaotic systems with hidden attractors

Chaotic systems are hard to synchronize, and no general solution exists. The presence of hidden attractors makes finding a solution particularly elusive. Successful synchronization critically depends on the control strategy, which must be carefully chosen considering system features such as the presence of hidden attractors. We studied the feasibility of fuzzy control for synchronizing chaotic systems with hidden attractors and employed a special numerical integration method that takes advantage of the oscillatory characteristic of chaotic systems. We hypothesized that fuzzy synchronization and the chosen numerical integration method can successfully deal with this case of synchronization. We tested two synchronization schemes: complete synchronization, which leverages linearization, and projective synchronization, capitalizing on parallel distributed compensation (PDC). We applied the proposal to a set of known chaotic systems of integer order with hidden attractors. Our results indicated that fuzzy control strategies combined with the special numerical integration method are effective tools to synchronize chaotic systems with hidden attractors. In addition, for projective synchronization, we propose a new strategy to optimize error convergence. Furthermore, we tested and compared different Takagi-Sugeno (T-S) fuzzy models obtained by tensor product (TP) model transformation. We found an effect of the fuzzy model of the chaotic system on the synchronization performance

Post-pandemic recovery strategies: revitalizing lifestyle entrepreneurship

The pandemic resulting from COVID-19 disease has brought about an unprecedented crisis to tourism destinations, resulting in an almost complete shutdown of tourist flows. Whereas disaster recovery models focus on prevention and preparedness, the post-pandemic recovery strategies are underexplored, particularly in relation to the highly representative group of small-scale businesses run by tourism lifestyle entrepreneurs (TLEs). An integrated framework for Destination Marketing Organization (DMO) strategic thinking is developed using the Delphi method with Q-sort technique. Findings from a 26-element expert panel emphasize the priority of creating a favorable environment for small-scale business development and supporting the provision of resources and capabilities. After this initial effort to strengthen these fragile businesses, it is essential to increase their communication capacity, a common limitation of TLEs, allowing these entrepreneurs to access niche markets more suited to the business and lifestyle they run. With stronger businesses, DMOs can enhance destination competitiveness and innovation, stimulating cooperation and networking.info:eu-repo/semantics/acceptedVersio

Wear Behavior of a Ni/Co Bilayer Coating by Physical Vapor Deposition on AISI 1045 Steel

Coatings by physical vapor deposition (PVD) have become highly relevant due to their wide range of applications and the rapid rate of coating formation. In this work, AISI steel 1045 was coated with two layers, Ni and Co using the PVD technique. Each coating was deposited with a thickness of 1 μm. After applying the coatings, a post-treatment was applied in an AC plasma reactor using a boron nitride blank in an Ar atmosphere at a pressure of 3 Torr, 0.3 A, and 460 V at 4, 8, and 12h. The post-treatment was characterized by optical emission spectroscopy (OES) in a range of 200-1100 nm. The main species observed by OES were Ar+, N2, N2+, and B+. The coatings on 1045 steel and posttreatment were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Also, were subjected to tribological tests to analyze wear resistance, using the Pin-on-Disk technique. The coatings on steel 1045 present remarkably better wear properties than the uncoated 1045 steel, being the sample post-treated at 4h that showed a lower wear rate

For which infants with viral bronchiolitis could it be deemed appropriate to use albuterol, at least on a therapeutic trial basis?

Although there is increasing evidence showing that infants with viral bronchiolitis exhibit a high degree of heterogeneity, a core uncertainty shared by many clinicians is with regard to understanding which patients are most likely to benefit from bronchodilators such as albuterol. Based on our review, we concluded that older infants with rhinovirus (RV) bronchiolitis, especially those with a nasopharyngeal microbiome dominated by Haemophilus influenzae; those affected during nonpeak months or during non-respiratory syncytial virus (RSV) predominant months; those with wheezing at presentation; those with clinical characteristics such as atopic dermatitis or a family history of asthma in a first-degree relative; and those infants infected with RSV genotypes ON1 and BA, have the greatest likelihood of benefiting from albuterol. Presently, this patient profile could serve as the basis for rational albuterol administration in patients with viral bronchiolitis, at least on a therapeutic trial basis, and it could also be the starting point for future targeted randomized clinical trials (RCTs) on the use of albuterol among a subset of infants with bronchiolitis

Seminal plasma AnnexinA2 protein is a relevant biomarker for stallions which require removal of seminal plasma for sperm survival upon refrigeration

Some stallions yield ejaculates that do not tolerate conservation by refrigeration prior to artificial insemination (AI), showing improvement after removal of most of the seminal plasma (SP) by centrifugation. In this study, the SP-proteome of 10 different stallions was defined through high-performance liquid chromatography with tandem mass spectrometry and bioinformatic analysis in relation to the ability of the ejaculates to maintain semen quality when cooled and stored at 5°C. Stallions were classified into three groups, depending on this ability: those maintaining good quality after direct extension in a commercial extender (good), stallions requiring removal of seminal plasma (RSP) to maintain seminal quality (good-RSP), and stallions, unable to maintain good semen quality even after RSP (poor). Pathway enrichment analysis of the proteins identified in whole equine SP using human orthologs was performed using g: profiler showing enriched Reactome and the Kyoto Encyclopedia of Genes and Genomes pathways related to hexose metabolism, vesicle mediated transport, post translational modification of proteins and immune response. Specific proteins overrepresented in stallions tolerating conservation by refrigeration included a peroxiredoxin-6 like protein, and transcobalamin-2, a primary vitamin B12-binding, and transport protein. Also, the protein involved in protein glycosylation, ST3 beta-galactoside alpha-2,3-sialyltransferase 1 was present in good stallions. These proteins were nearly absent in poor stallions. Particularly, annexinA2 appeared as to be the most powerful discriminant variable for identification of stallions needing RSP prior to refrigeration, with a P = 0.002 and a q value = 0.005. Overall this is the first detailed study of the equine SP-proteome, showing the potential value of specific proteins as discriminant bio-markers for clinical classification of stallions for AI

Proper motions of the HH1 jet

We describe a new method for determining proper motions of extended objects, and a pipeline developed for the application of this method. We then apply this method to an analysis of four epochs of [S~II] HST images of the HH~1 jet (covering a period of $\sim 20$~yr). We determine the proper motions of the knots along the jet, and make a reconstruction of the past ejection velocity time-variability (assuming ballistic knot motions). This reconstruction shows an "acceleration" of the ejection velocities of the jet knots, with higher velocities at more recent times. This acceleration will result in an eventual merging of the knots in $\sim 450$~yr and at a distance of $\sim 80"$ from the outflow source, close to the present-day position of HH~1.Comment: 12 pages, 8 figure

Plyometric Training in Female Volleyball Players. Systematic Review

El voleibol femenino se práctica en todo el mundo a nivel profesional y amateur. Los saltos verticales son una parte fundamental para el desarrollo de este deporte, por lo que el entrenamiento pliométrico puede ser eficaz para un aumento del rendimiento. El propósito de estudio fue describir cuáles han sido los métodos y programas de entrenamiento pliométrico en mujeres que practican voleibol, así como el resultado obtenido en función de estos. El proceso de búsqueda en las bases de datos se llevó a cabo desde Marzo hasta Junio de 2016. Las bases de datos consultadas fueron Pubmed, Web of Science, Cochrane y SPORTDiscus. La revisión sistemática fue realizada bajo las recomendaciones de la declaración PRISMA. La calidad metodológica de los estudios fue evaluada mediante la Escala PEDro. Como resultado, se obtuvieron un total de 205 artículos tras eliminar aquellos que estaban por duplicado. Finalmente 7 artículos fueron seleccionados. Los resultados principales fueron que aquellos estudios que utilizan deportistas amateurs obtienen mejores resultados que los realizados con deportistas profesionales cuando se realizan programas de entrenamiento pliométrico. También se indica que un período de entrenamiento pliométrico de baja intensidad puede prevenir una disminución en la altura del salto vertical; así como es necesario programar la pretemporada para evitar pérdida en la capacidad de salto. Todo ello parece indicar, como conclusión, que es necesario una disminución del volumen y un aumento de la intensidad en el entrenamiento pliométrico.Female volleyball is practiced all over the world at a professional and amateur level. Vertical jumps are a fundamental part of the development of this sport. In this sense, plyometric training can be effective for increased performance. The purpose of the study was to describe the methods and programs of plyometric training in women volleyball players, as well as the results obtained from them. The following electronic databases were searched March to June 2016. Electronic databases consulted were Pubmed, Web of Science, Cochrane and SPORTDiscus. This systematic review was performed following PRISMA statement. PEDro scale was used to evaluated the methodological quality of the included studies. As total of 205 articles were obtained after remove duplicates. Finally 7 articles were selected. The main results were that those studies using amateur athletes obtain better results than those performed with professional athletes when performing plyometric training programs. It is also indicated that a period of low intensity plyometric training could prevent a decrease in vertical jump height; As well as it is necessary to schedule the preseason to avoid loss in the ability to jump. All this seems to indicate, in conclusion, that a decrease in volume and an increase in intensity in the training of plyometric training is necessary