Transients in the Synchronization of Oscillator Arrays

The purpose of this note is threefold. First we state a few conjectures that allow us to rigorously derive a theory which is asymptotic in N (the number of agents) that describes transients in large arrays of (identical) linear damped harmonic oscillators in R with completely decentralized nearest neighbor interaction. We then use the theory to establish that in a certain range of the parameters transients grow linearly in the number of agents (and faster outside that range). Finally, in the regime where this linear growth occurs we give the constant of proportionality as a function of the signal velocities (see [3]) in each of the two directions. As corollaries we show that symmetric interactions are far from optimal and that all these results independent of (reasonable) boundary conditions.Comment: 11 pages, 4 figure

Evaluación de las competencias docentes de los facilitadores que imparten cursos de postgrado y maestría en la Facultad de Ciencias de la Educación de la Universidad de Panamá durante el período académico 2008 - 2010

En los últimos años, la Universidad de Panamá ha creado Programas de Educación superior, muchos de los cuales se han visto fortalecidos con los estudios de Postgrado, ya que el país espera que una serie de profesionales, al más alto nivel de formación, puedan desempeñarse en las diferentes disciplinas. La evaluación por competencias docentes, a nivel superior en el claustro universitario, es relativamente de las innovaciones que a raíz de la aprobación de la Ley 30 del 20 de julio de 2006, la cual crea el Sistema Nacional de Evaluación y Acreditación para el Mejoramiento de la Calidad de la Educación Superior Universitaria, esto es un proceso permanente, dirigido a detectar necesidades, corregir y mejorar acciones, con el fin de lograr eficacia, eficiencia y equidad de los planes y programas formativos. La evaluación por competencias requiere de la formulación de juicios basados en análisis cuidadosos y críticos de situaciones específicas, esto con el fin de que las decisiones que se tomen sean las mejores y fundamentadas, al mismo tiempo que permitan hacer útiles las propuestas de acción futura

Analysis of Representativeness of the Paramo Ecosystem in the Conservation Modalities of the Chimborazo Province

The paramo ecosystem has ecological, social, cultural and economic importance due to the ecosystemic services of supply, regulation, support and culture that it provides to local populations for their well-being, therefore, it needs to be conserved and managed from an ecosystemic approach. The objective of this work is to analyze the conservation modalities that protect the paramo ecosystem in the Chimborazo province. To conduct the research, a systematic review of 30 cartographic sources was carried out, and documentary information on 7 variables of the paramo ecosystem was made, provided by institutions in charge of managing the province's natural resources, and found in articles consulted in scientific and academic databases. Additionally, gray literature has been included through manual search. The results indicate that the Chimborazo province has 17.93% of its extension under conservation modality, through 121 protected natural spaces, distributed in 3 modalities. The paramo ecosystem represents 36.40% of the province's size, and is made up of 9 vegetation formations. 15.10% of this ecosystem are under conservation modality, however, only 3 of the 121 spaces have planning documents for the management of these spaces. Keywords: paramo ecosystem, ecosystem services, conservation modalities. Resumen El ecosistema páramo tiene importancia ecológica, social, cultural y económica por los servicios ecosistémicos de abastecimiento, regulación, soporte y culturales que suministra a las poblaciones locales para su bienestar, por tanto, requiere ser conservado y manejado desde un enfoque ecosistémico. El objetivo de este trabajo es analizar las modalidades de conservación que protegen el ecosistema páramo en la provincia de Chimborazo. Para llevar a cabo la investigación se realizó una revisión sistémica de 30 fuentes de información cartográfica y documental sobre 7 variables del ecosistema páramo, facilitadas por instituciones encargadas del manejo de los recursos naturales de la provincia, y encontradas en artículos consultados en bases de datos científicas y académicas, adicionalmente se ha incluido literatura gris mediante la búsqueda manual. Los resultados indican que la provincia de Chimborazo tiene 17,93% de su extensión bajo modalidad de conservación, a través de 121 espacios naturales protegidos, distribuidos en 3 modalidades. El ecosistema páramo representa el 36,40% de la extensión de la provincia y está conformada por 9 formaciones vegetales. El 15,10% de éste ecosistema se encuentran bajo modalidad de conservación, sin embargo, únicamente 3 de los 121 espacios poseen documentos para el manejo de estos espacios. Palabras clave: ecosistema páramo, servicios ecosistémicos, modalidades de conservación

Estudio de Necesidades de señalización en la Universidad Técnica de Manabí para mitigar riesgos

Abstract— La señalética es una disciplina del diseño gráfico relacionada con la comunicación; es la información que estudia y desarrolla un sistema de comunicación visual, que es reducido a un conjunto de señales o símbolos gráficos de fácil compresión, los cuales cumplen la función de guiar a una persona o conjunto de personas en aquellos puntos o lugares donde se prestan servicios o se planteen dudas acerca del comportamiento. El objetivo de esta investigación fue identificar los lugares más afectados por la escasez de señalización dentro de la Universidad Técnica de Manabí (UTM) y los tipos de señaléticas adecuadas para estos. Para ello, se utilizó las principales técnicas de recolección de información, en las cuales se aplicaron los métodos cualitativos y cuantitativos. La población de esta investigación, como antes mencionada, es la UTM, de la cual se tomó como muestra un 20% que es perteneciente a las facultades de Medicina, Electricidad, Idiomas y el Instituto de Ciencias Básicas (ICB) Con los resultados obtenidos se demostró que el tema de la investigación realizada es de interés entre los involucrados, reconociendo la falta de señaléticas en diferentes puntos, lo cual está provocando el irrespeto de los conductores hacia los peatones o ciclistas, corroborando con ello la necesidad de cubrir diferentes áreas con señales que disminuyan el riesgo en el interior de la universidadn.   Index Terms— señales, riesgo, disciplin

Multidrug resistance protein 1 localization in lipid raft domains and prostasomes in prostate cancer cell lines

Background: One of the problems in prostate cancer (CaP) treatment is the appearance of the multidrug resistance phenotype, in which ATP-binding cassette transporters such as multidrug resistance protein 1 (MRP1) play a role. Different localizations of the transporter have been reported, some of them related to the chemoresistant phenotype. Aim: This study aimed to compare the localization of MRP1 in three prostate cell lines (normal, androgen-sensitive, and androgen-independent) in order to understand its possible role in CaP chemoresistance. Methods: MRP1 and caveolae protein markers were detected using confocal microscopy, performing colocalization techniques. Lipid raft isolation made it possible to detect these proteins by Western blot analysis. Caveolae and prostasomes were identified by electron microscopy. Results: We show that MRP1 is found in lipid raft fractions of tumor cells and that the number of caveolae increases with malignancy acquisition. MRP1 is found not only in the plasma membrane associated with lipid rafts but also in cytoplasmic accumulations colocalizing with the prostasome markers Caveolin-1 and CD59, suggesting that in CaP cells, MRP1 is localized in prostasomes. Conclusion: We hypothesize that the presence of MRP1 in prostasomes could serve as a reservoir of MRP1; thus, taking advantage of the release of their content, MRP1 could be translocated to the plasma membrane contributing to the chemoresistant phenotype. The presence of MRP1 in prostasomes could serve as a predictor of malignancy in Ca

Protection and reversion role of a pure stilbene extract from grapevine shoot and its major compounds against an induced oxidative stress

Sulfur dioxide is a controversial preservative used in winemaking. Given its potential toxicity, it is of great interest to find alternatives aimed at replacing or reducing sulfur dioxide. The objective was to assess the antioxidant effects of a grapevine-shoot extract with 99% of stilbenes (ST-99), its major compounds (trans-resveratrol and trans-?-viniferin) and their mixture (1:3.9) by measuring reactive oxygen species (ROS) and glutathione (GSH) levels in vitro. Their ability to protect against or reverse the effects of H2O2 on cells were also studied. The results showed that ST-99, followed by trans-ε-viniferin and the mixture, were able to reduce ROS levels, increased GSH content and exhibited antioxidant ability against an induced oxidative stress. Trans-resveratrol significantly reduced ROS content only at the highest concentrations. ST-99 at non-cytotoxic concentrations is more effective than the other compounds, which might be attributed to increased levels of GSH. The results suggest a promising use of ST-99.Développement d'une infrastructure française distribuée pour la métabolomique dédiée à l'innovatio

Translation initiation downstream from annotated start codons in human mRNAs coevolves with the Kozak context

Eukaryotic translation initiation involves preinitiation ribosomal complex 5′ -to-3′ directional probing of mRNA for codons suitable for starting protein synthesis. The recognition of codons as starts depends on the codon identity and on its immediate nucleotide context known as Kozak context. When the context is weak (i.e., nonoptimal), leaky scanning takes place during which a fraction of ribosomes continues the mRNA probing. We explored the relationship between the context of AUG codons annotated as starts of protein-coding sequences and the next AUG codon occurrence. We found that AUG codons downstream from weak starts occur in the same frame more frequently than downstream from strong starts. We suggest that evolutionary selection on in-frame AUGs downstream from weak start codons is driven by the advantage of the reduction of wasteful out-of-frame product synthesis and also by the advantage of producing multiple proteoforms from certain mRNAs. We confirmed translation initiation downstream from weak start codons using ribosome profiling data. We also tested translation of alternative start codons in 10 specific human genes using reporter constructs. In all tested cases, initiation at downstream start codons was more productive than at the annotated ones. In most cases, optimization of Kozak context did not completely abolish downstream initiation, and in the specific example of CMPK1 mRNA, the optimized start remained unproductive. Collectively, our work reveals previously uncharacterized forces shaping the evolution of protein-coding genes and points to the plurality of translation initiation and the existence of sequence features influencing start codon selection, other than Kozak context.Russian Science Foundation (RSF) 20-14-00121Science Foundation Ireland 210692/Z/18/ZScience Foundation Ireland 12/RC/2276_P2Erasmus+ ProgrammePlan Propio de Investigacion 2019 de la Universidad de GranadaMinistry of Economy of Spain DPI2017-84439-REuropean Union (EU) DPI2017-84439-