Uniqueness criteria for ordinary differential equations with a generalized transversality condition at the initial condition

In this paper, we present some uniqueness results for systems of ordinary differential equations. All of them are linked by a weak transversality condition at the initial condition, which generalizes those in the previous literature. Several examples are also provided to illustrate our results

Population study of Steneotarsonemus spinki (Acari: Tarsonemidae) on three varieties rice sowing in different times.

Pests and diseases are among the most important limiting factors for rice (Oryza sativa) production, as they are responsible for 35 % of economic losses. The adoption of adequate control measures in order to ensure better production rates is required. The Steneotarsonemus spinki mite is a pest that has generated many losses in the rice sector in recent years. The Colombian Agricultural Institute declared in 2005 that the presence of the disease known as “vain grain”, which affects grain quality and crop productivity up to 60 %, generated economic losses for farmers. S. spinki, is part of the complex of organisms that cause “vain grain”. Therefore the objective of this work was to evaluate the population dynamics of S. spinki in different sowing dates in the Agrosavia investigation center of Agustín Codazzi, Cesar, Colombia. For this objective, during 2014 three different rice varieties were sown every 20 +/- 3 days, for a total of seven plantings in a complete block design sown at random in fixed strips with four replications. At 60 days of emergence after each sowing, four plants were taken per replicate per variety at each sampling, with a total of five samplings being performed during the growth stage. In the CI Motilonia entomology unit, the number of mites were counted in the pods of the last three leaves of the central till of each plant. The populations of S. spinki exceeded 100 individuals per plant in some samples, the variety FED 733 presented the largest population of the mite, and the variety FED 2000 represented the smallest one. According to the results, the populations of S. spinki increased in the second semester in advanced physiological stages of the crop. Mite populations appear to have no effect on the yields of the rice varieties evaluated

New Lipschitz–type conditions for uniqueness of solutions of ordinary differential equations

We present some generalized Lipschitz conditions which imply uniqueness of solutions for scalar ODEs. We illustrate the applicability of our results with examples not covered by earlier Lipschitz–type uniqueness testsRodrigo López Pouso and Jorge Rodríguez López were partially supported by grant ED431C 2019/02, Xunta de Galicia (Spain), and by Ministerio de Ciencia y Tecnología (Spain), grant PID2020-113275GB-I00S

Desenvolvismo, ditadura e pós-ditadura: o discurso pedagógico e poder no Chile

AbstractThis paper, that is a result of a reflection, from the points of view of Michel Foucault and Basil Berstein, analyzes how the device of control imposed by The Military Junta to Chilean education, (Chile, 1973), introduces four mayor control mechanisms (discipline, authority, control and examination and curricular standardization). This device is analyzed in the context of the history of Chilean education during the whole period 1950-1995 and, more specifically, in the post-dictatorial period, a period called the “Pedagogy of Oblivion”.En este artículo se presenta una reflexión a partir de conceptos desarrollados por Michel Foucault y Basil Berstein. Se analiza el papel del dispositivo de control que se ejerce en la educación chilena por la Junta Militar (Chile, 1973), a través de cuatro mecanismos: disciplina, autoridad, examen y control y estandarización curricular. Se analiza en conjunto el papel de este dispositivo en el marco de la historia de la educación chilena en el período 1950-1995, en especial se destaca el fenómeno denominado “pedagogía del olvido”.ResumoEste artigo apresenta uma reflexão baseada nos conceitos desenvolvidos por Michel Foucault e Basil Bernstein. Analisamos o papel do dispositivo de controle posto em prática na educação chilena utilizando quatro mecanismos propostos pela junta militar (disciplina, autoridade, controle e análise de currículos e de normalização). Analisa-se o papel deste dispositivo no contexto da história da educação no Chile no período 1950-1995. Sobretudo, destaca o fenômeno conhecido como “pedagogia do esquecimento

Reflexiones sobre la protección del consumidor de servicios turísticos frente a la publicidad engañosa de sociedades mercantiles turísticas

En la presente Comunicación, sus autores pretenden exponer la situación en la que los potenciales clientes de las empresas turísticas pueden sufrir engaños como consecuencia de la publicidad engañosa. En tales supuestos, el mercado se suele caracterizar por el uso de una determinada publicidad que pretende incidir en la voluntad del consumidor, de manera que la actividad publicitaria se muestra como realmente relevante y decisiva para la formación de la voluntad de los referidos consumidores en orden a la celebración del contrato. Estos casos en los que la publicidad engañosa ha resultado relevante para que el turista–consumidor otorgue su consentimiento merecen una especial reflexión, labor que los autores intentan acometer en este estudio

Alimentação e doenças neurodegenerativas: uma questão sócio-científica para o desenvolvimento da capacidade argumentativa

The article shows the results of a research project whose objective was to promote the development of argumentative skills in a group of trainee teachers of the Chemistry degree program at the National Pedagogical University, through the design and application of a didactic unit on the implications of food chemistry in the development and prevention of the Parkinson’s disease [PD] as a socio-scientific issue. Activities such as open questions, discussion forums, and search for possible nutritional alternatives in the prevention and treatment for the PD were implemented. In each stage, the level of argumentation wasidentified, and the conceptual content of each argument was analyzed. It should be noted that the students were able to achieve a higher level of argumentation than the initial one by using the knowledge acquired in the solution and search for alternatives through active and reflective learning. They built arguments based on theoretical and experimental grounds on different aspects of this controversy.El artículo muestra los resultados de un trabajo de investigación cuyo objetivo fue favorecer el desarrollo de la habilidad argumentativa en un grupo de profesores en formación inicial del programa de Licenciatura en Química de la Universidad Pedagógica Nacional, mediante el diseño y la aplicación de una unidad didáctica sobre las implicaciones de la química de alimentos en el desarrollo y prevención de la enfermedad de Parkinson [EP] como una cuestión sociocientífica. Se implementaron actividades como preguntas abiertas, foros de discusión y búsqueda de posibles alternativas nutricionales en la prevención y tratamiento de la EP. En cada una de las etapas se identificó el nivel de argumentación y se analizó el contenido conceptual de cada argumento. Se destaca que los estudiantes lograron alcanzar un nivel de argumentación superior al inicial al aplicar los conocimientos adquiridos en la resolución y búsqueda de alternativas por medio de un aprendizaje activo y reflexivo. Construyeron argumentos basados en fundamentos teóricos y experimentales sobre diferentes aspectos de esta controversia.O artigo apresenta os resultados da pesquisa cujo objetivo era promover o desenvolvimento de habilidades argumentativas num grupo de professores estagiários do programa da Licenciatura em Química da Universidade Pedagógica Nacional, através da concepção e aplicação de uma unidade didática sobre as implicações da química alimentar no desenvolvimento e prevenção da Doença de Parkinson [DP] como uma questão sóciocientífica. Atividades como perguntas abertas, fóruns de discussão e busca de possíveisalternativas nutricionais na prevenção e tratamento para a DP foram implementadas. Em cada etapa, identificou-se o nível de argumentação e analisou-se o conteúdo conceitual de cada argumento. Destaca-se que os estudantes foram capazes de alcançar um nível de argumentação superior ao inicial, aplicando os conhecimentos adquiridos na resolução e buscando alternativas através de um aprendizado ativo e reflexivo. Eles construíram argumentos baseados em fundamentos teóricos e experimentais sobre diferentes aspectos desta controvérsia

Recombinant AMP/Polypeptide Self-Assembled Monolayers with Synergistic Antimicrobial Properties for Bacterial Strains of Medical Relevance

Producción CientíficaNosocomial infections are one of the most frequent causes of indwelling biomedical device failure. In this regard, the use of antibiofilm nanocoatings based on antimicrobial peptides (AMPs) is a promising alternative to prevent multiresistant biofilm infections. However, the limitations of chemical production impede the large-scale development of advanced antimicrobial materials that improve the properties of AMPs. Herein, we present a multifunctional modular design for the recombinant coproduction of self-assembled monolayers (SAMs) based on AMPs and elastin-like recombinamers (ELRs), which combine the antimicrobial properties of a designer AMP, GL13K, and low-fouling activity of an ELR in a synergistic manner. The inclusion of a grafting domain intended for oriented tethering onto surfaces allowed the recombinant polymers to be covalently immobilized onto model gold surfaces. The antibiofilm properties against two of the bacterial strains most frequently responsible for indwelling medical device-associated infections, namely Staphylococcus epidermidis and Staphylococcus aureus, were then evaluated. GL13K peptide was found to provide antibiofilm properties to the surface, with these being synergistically enhanced by the antifouling effect of the ELR. This new design offers a promising tool for the development of advanced AMP-based nanocoatings for medical devices with powerful and enhanced features.Comisión Europea (project NMP-2014-646075)Ministerio de Economía, Industria y Competitividad (project PCIN-2015-010 / MAT2015-68901-R / MAT2016-78903-R)Junta de Castilla y León (project VA317P18

Effects of short-term in-season break detraining on repeated-sprint ability and intermittent endurance according to initial performance of soccer player

To better understand the detraining effects in soccer, the purpose of the study was to ana- lyse if performance level of soccer players modulate repeated-sprint ability (RSA) and inter- mittent endurance changes during 2-weeks of detraining (i.e., in-season break). Seventeen professional and sixteen young elite soccer players of two different teams performed, before and after 2-weeks of detraining, the RSA test and the Yo-Yo Intermittent Recovery Test, level 1 (YYIR1). Before detraining, professional players perform better (p < 0.05) RSA best time (RSAbest) than young players. A decrease (p < 0.05) in RSAbest, RSA total time (RSAtotal) and mean time (RSAmean) performance was observed in both teams, without changes in RSA fatigue index (Sdec). No significant changes in distance covered during YYIR1 was observed in any team. Before detraining, faster players from both teams (FG) (following the median split technique, soccer players with RSAbest 3.95 s) performed bet- ter (p < 0.01) in RSAtotal, RSAmean and RSAbest, but worse (p < 0.01) in Sdec. Although FG and the slower players (SG, RSAbest > 3.95 s) showed a worse (p < 0.05) RSAtotal, RSAbest and RSAmean performance after detraining (ES = 1.5, 1.4 and 2.9; ES = 0.6, 1.2 and 0.6; for FG and SG, respectively), the deterioration was greater in the FG for RSAbest (p < 0.05) and RSAtotal (ES = 1.46). After detraining, FG improved (p < 0.05) Sdec performance. In conclu- sion, a 2-week in-season break (detraining) period induced a worse RSA, with no effect on intermittent endurance in professional and elite young soccer players, with greater detrimen- tal effects on RSAtotal and RSAbest in FG. In addition, Sdec does not seem to be sensitive to changes in RSA after a 2-week in-season break.S

Valorización de la empresa Unión Andina de Cementos - UNACEM

Como resultado de la evaluación objetivo del presente trabajo de investigación, se llegó a la conclusión de recomendar la compra de acciones de UNACEM, el cual tiene la capacidad de explotar su posición dominante en el mercado cementero, así como las sinergias derivadas de la integración vertical con sus subsidiarias. Asimismo, ha realizado importantes inversiones en ampliación de capacidad productiva y la consolidación de su presencia internacional