Review on computational methods for Lyapunov functions

Lyapunov functions are an essential tool in the stability analysis of dynamical systems, both in theory and applications. They provide sufficient conditions for the stability of equilibria or more general invariant sets, as well as for their basin of attraction. The necessity, i.e. the existence of Lyapunov functions, has been studied in converse theorems, however, they do not provide a general method to compute them. Because of their importance in stability analysis, numerous computational construction methods have been developed within the Engineering, Informatics, and Mathematics community. They cover different types of systems such as ordinary differential equations, switched systems, non-smooth systems, discrete-time systems etc., and employ di_erent methods such as series expansion, linear programming, linear matrix inequalities, collocation methods, algebraic methods, set-theoretic methods, and many others. This review brings these different methods together. First, the different types of systems, where Lyapunov functions are used, are briefly discussed. In the main part, the computational methods are presented, ordered by the type of method used to construct a Lyapunov function

Monitoreo del progreso del alumno en la identificación de riesgo en la lectura

Este estudo tem por nalidade analisar o uso da monitorização com base no currículo como sistema escolar de identi cação de alunos em risco na leitura, no contexto de um modelo educativo baseado no grau de resposta à intervenção. Realizou-se uma investigação quantitativa em que participaram todos os alunos do 3o ano (82 alunos) de um agrupamento de escolas do norte de Portugal. O tratamento de dados foi feito com recurso à estatística descritiva e inferencial. Destacam-se, entre outras conclusões, a existência de dez alunos em risco na leitura durante todo o ano letivo e o facto de, no nal do 3o ano de escolaridade, a média de resultados dos alunos que nunca estiveram em risco ser superior ao dobro da média de resultados dos alunos que estiveram em risco todo o ano.This study aims to analyze the use of curriculum-based monitoring as a school system to identify students at risk in reading, in the context of an educational model based on the degree of response to intervention. A quantitative investigation was conducted with all third grade students (82 students) from a group of schools in the north of Portugal. Data processing was done using descriptive and inferential statistics. Among the conclusions, the following stand out: the existence of ten students at risk in reading throughout the school year and the fact that, at the end of the third year of schooling, the mean results of students who were never at risk was more than double the mean results of students who were at risk for the entire year.Cette étude a pour but d’analyser l’usage du contôle ayant pour base le coursus comme système scolaire d’identification des élèves présentant des risques dans la lecture, dans le contexte d’un modèle éducatif fondé sur le degrée de réponse à l’intervention. On a fait une investigation quantitative à laquelle ont participé tous les élèves de CM1 (82 élèves) d’un groupement d’écoles du nord du Portugal. Le traitement des données a été fait à l’aide de la statistique descriptive et inférentielle. On souligne, entre autres conclusions, l’existence de dix élèves en risque dans la lecture pendant toute l’année scolaire et le fait qu’à la fin de la troisièmme année de scolarité, la moyenne des résultats des élèves n’ayant jamais été en risque soit supérieur au double de la moyenne des résultats des élèves qui ont été en risque toute l’année.Este estudio tiene la finalidad de analizar el uso del monitoreo del currículo como sistema escolar de identificación de alumnos en riesgo en la lectura, en el marco de un modelo educativo basado en el grado de respuesta a la intervención. Se llevó a cabo una investigación cuantitativa en la que participaron todos los alumnos del 3er año (82 alumnos) de un agrupamiento de escuelas del norte de Portugal. El tratamiento de datos se efectuó por medio de la estadística descriptiva e de inferencias. Se destacan, entre otras conclusiones, la existencia de diez alumnos en riesgo en la lectura durante todo el año lectivo y el hecho de que, al final del 3er año de escolaridad, el promedio de resultados de los alumnos que nunca estuvieron en riesgo era superior al doble del promedio de resultados de los alumnos que estuvieron en riesgo todo el año.(undefined)info:eu-repo/semantics/publishedVersio

Expression and function of G-protein-coupled receptorsin the male reproductive tract

This review focuses on the expression and function of muscarinic acetylcholine receptors (mAChRs), α1-adrenoceptors and relaxin receptors in the male reproductive tract. The localization and differential expression of mAChR and α1-adrenoceptor subtypes in specific compartments of the efferent ductules, epididymis, vas deferens, seminal vesicle and prostate of various species indicate a role for these receptors in the modulation of luminal fluid composition and smooth muscle contraction, including effects on male fertility. Furthermore, the activation of mAChRs induces transactivation of the epidermal growth factor receptor (EGFR) and the Sertoli cell proliferation. The relaxin receptors are present in the testis, RXFP1 in elongated spermatids and Sertoli cells from rat, and RXFP2 in Leydig and germ cells from rat and human, suggesting a role for these receptors in the spermatogenic process. The localization of both receptors in the apical portion of epithelial cells and smooth muscle layers of the vas deferens suggests an involvement of these receptors in the contraction and regulation of secretion.Esta revisão enfatiza a expressão e a função dos receptores muscarínicos, adrenoceptores α1 e receptores para relaxina no sistema reprodutor masculino. A expressão dos receptores muscarínicos e adrenoceptores α1 em compartimentos específicos de dúctulos eferentes, epidídimo, ductos deferentes, vesícula seminal e próstata de várias espécies indica o envolvimento destes receptores na modulação da composição do fluido luminal e na contração do músculo liso, incluindo efeitos na fertilidade masculina. Além disso, a ativação dos receptores muscarínicos leva à transativação do receptor para o fator crescimento epidermal e proliferação das células de Sertoli. Os receptores para relaxina estão presentes no testículo, RXFP1 nas espermátides alongadas e células de Sertoli de rato e RXFP2 nas células de Leydig e germinativas de ratos e humano, sugerindo o envolvimento destes receptores no processo espermatogênico. A localização de ambos os receptores na porção apical das células epiteliais e no músculo liso dos ductos deferentes de rato sugere um papel na contração e na regulação da secreção.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de FarmacologiaUNIFESP, EPM, Depto. de FarmacologiaSciEL

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Aspectos econômicos da cultura do abacaxi: sazonalidade de preços no Estado do Rio de Janeiro Economic aspects of the pineapple culture: seasonally of prices in Rio de Janeiro state

O presente estudo teve como objetivo a determinação do padrão de variação sazonal dos preços médios recebidos pelos produtores de abacaxi das Regiões Norte e Noroeste Fluminense, no período de janeiro de 1995 a dezembro de 2001. Para tanto, adotou-se a metodologia da média geométrica móvel centralizada de 12 meses. Os resultados do estudo mostraram uma sazonalidade de preços do abacaxi moderada. No período de janeiro a outubro, ocorreu certa estabilidade de preços, apresentando valores máximos nos meses de março e abril. Os meses de novembro e dezembro apresentaram os menores valores recebidos pelos produtores de abacaxi.<br>The present work has as aim the determination of the pattern of seasonal variation of the medium prices received by the producers of pineapple from the North and Northwest Fluminense region, in the period of January 1995 to December 2001. For that study, the methodology of the centralized average geometric mobile was adopted. The results of the work showed a seasonality of reasonable prices. In the period of January to October certain stability of prices occurred, presenting maximum values in March and April. The months of November and December are the ones that presented the smallest values received by the producers