Josep Pérez

La agroecología tiene como objetivo el conocimiento de los elementos y procesos claves en el funcionamiento de los agrosistemas, para su eficaz gestión en armonía con el ambiente. La protección vegetal ha sido enfocada tradicionalmente, bajo el concepto de lucha y control, utilizando arsenales químicos o biológicos y, en estos momentos, biotecnológicos. La aplicación de criterios ecológicos en protección vegetal ha permitido desarrollar procesos como la biofumigación, fundamentada en la utilización de los gases resultantes de la biodescomposición de la materia orgánica para el manejo de organismos patógenos de los vegetales. Es de esperar que el futuro de la agricultura muestre una mayor preocupación por el ambiente, la conservación de los recursos naturales, la salud de las personas y se destaque su contribución a la reducción de la pobreza, así como su aportación al desarrollo de los agrocombustibles.

The construct of the self is important in the domain of memory research. Recent work has shown that person memory is influenced by similarity of social targets to the self. The current experiments investigate self-similarity as defined by traits and political ideology to better understand how memory for social targets is organised. Across three experiments, participants formed positive or negative impressions based on each target’s picture, a trait-implying behavior (Experiments 1 & 2), and/or political ideology (conservative/liberal label in Experiment 2; political-ideological belief statements in Experiment 3) followed by a memory test. Results showed a self-similarity effect dependent on valence in Experiment 1, but not in Experiments 2 or 3 when participants processed ideological information associated with targets. These results suggest that self-similarity has an effect on memory for social targets, but that ideological information disrupts self-focused processing of others, suggesting that ideological information also has a powerful influence on what people remember about others (i.e. social targets).

The pandemic outbreak in March 2020 and its associated sanitary regulations and restrictions triggered an abrupt and significant change for society in general and for families’ organization in particular. In Chile, the Santiago Metropolitan District was under a strict lockdown that involved the closure of the entire educational system. From a systemic-family stress perspective, the impact of these changes might have consequences not only for each individual family member, but for the parental dynamic and, consequently, for children’s well-being. This paper presents the results of a follow-up study showing changes in self-reported parental depression and the perceived home organization of mothers and fathers assessed at three different moments: before the pandemic, at the initial outbreak, and after 1 month of strict lockdown. Relevant moderators were explored using linear mixed models to understand the within-subject changes in mothers’ and fathers’ self-reports across the different assessment times. Financial strain, personality traits of self-criticism and dependency, previous parent–child quality interaction, recent major stressful events, and number of children are highlighted as relevant factors that moderate changes in home chaos and parental mental health perception. Significant risks and protective factors are described for fathers and mothers. The use of pre-pandemic measures as baseline levels enabled the identification of personal and family characteristics that were related to better outcomes. The results help increase our understanding of the sanitary regulations’ impacts on the family system and identify vulnerability indicators that should be considered.

Standard adaptive control is the preferred approach for stabilization and synchronization of chaotic systems when the structure of such systems is a priori known but the parameters are unknown. However, in the presence of unmodeled dynamics and/or disturbance, this approach is not effective anymore due to the drift of the parameter estimations, which eventually causes the instability of the closed-loop system. In this paper, a robustifying term, which consists of a saturation function, is used to avoid this problem. The robustifying term is added to the adaptive control law. Consequently, the learning law is also modified. The boundedness of the states and the parameter estimations is rigorously and thoroughly proven by means of Lyapunov like analysis based on Barbalat’s lemma. On these new conditions, the convergence to zero cannot be achieved due to the presence of unmodeled dynamics and/or disturbance. However, it is still possible to guarantee the asymptotic convergence to a bounded zone around zero. The width of this zone can be adjusted by the designer. The performance of this robust approach is verified by numerical simulations. Although, for simplicity, this strategy is only applied to the stabilization and synchronization of Zhang system, the procedure can easily be generalized to a broad class of chaotic systems.

The objective of this research is to conduct a comparative analysis of the two models of growth and development that were applied in Peru over the past six decades (1961-2021). The objective is to conduct a comparative analysis of the Import Substitution Model (ISM) and the Liberal Model (LM), to determine which of these models has demonstrated superior performance in terms of economic growth and social welfare for the country. In this instance, the documentary and systematic review of the material obtained from both physical and virtual libraries was employed as a method. Consequently, a variety of economic indicators have been examined, including the primary indicator of economic growth, gross domestic product (GDP), to account for the effects of inflation and ensure the accuracy of the data. Furthermore, the principal social indicators have been examined and contrasted to gauge the nation's social well-being. The findings of the study demonstrate that the ML has demonstrably outstripped the MSI in terms of economic growth and the enhancement of social welfare for Peruvian society over the past three decades. However, it would be erroneous to assume that this model has entirely resolved the country's economic and social challenges.