Vignettes and self-reported work disability in the United States: Correction of report heterogeneity

Subjective measures of health tend to suffer from bias given by reporting heterogeneity. however, some methodologies are used to correct the bias in order to compare self-assessed health for respondents with different sociodemographic characteristics. One of the methods to correct this is the hierarchical ordered probit (hopit), which includes rates of vignettes -hypothetical individuals with a fixed health state- and where two assumptions have to be fulfilled, vignette equivalence and response consistency. this methodology is used for the self-reported work disability for a sample of the united states for 2011. The results show that even though sociodemographic variables influence rating scales, adjusting for this does not change their effect on work disability, which is only influenced by income. the inclusion of variables related with ethnicity or place of birth does not influence the true work disability. however, when only one of them is excluded, it becomes significant and affects the true level of work disability as well as income.

Self-organized sociopolitical interactions as the best way to achieve organized patterns in human social systems: going beyond the top-down control of classical political regimes

La monografía presenta la auto-organización sociopolítica como la mejor manera de lograr patrones organizados en los sistemas sociales humanos, dada su naturaleza compleja y la imposibilidad de las tareas computacionales de los regímenes políticos clásico, debido a que operan con control jerárquico, el cual ha demostrado no ser óptimo en la producción de orden en los sistemas sociales humanos. En la monografía se extrapola la teoría de la auto-organización en los sistemas biológicos a las dinámicas sociopolíticas humanas, buscando maneras óptimas de organizarlas, y se afirma que redes complejas anárquicas son la estructura emergente de la auto-organización sociopolítica.

Metacognitive knowledge and self-regulation: A qualitative lecture of students functioning in writing

This research emerges from the world-wide problematic concerning student's failure. It particularly analyzes the meta-cognitive competences in the writing process of this population. Based on Flavell's (1992) viewpoint about meta-cognition and the socio-cognitive approach of self-regulation, two variables were measured: meta-cognitive knowledge and self-regulation strategies. A qualitative study was conducted on a sample of 12 French students at first year university. This study uses a specific technique of interview known as "explicitation interview". The data analysis included the categorization, codification and quantification of the information obtained with the interviews. In conclusion, even though the students had metacognitive knowledge related to the written tasks, they did not show strategies that could help to go beyond the descriptive modality of written discourses by taking into account the readers' expectations. Their writing processes focused on transcription of ideas with little control on the planning and revision phases.

Self-medication and related terms: a conceptual reflection

Introduction: self-medication has become a growing practice in the world population. This phenomenon has been promoted as a form of self-care, with a positive impact on reducing spending in health systems, however there is concern about the potential negative effects related to inadequate diagnosis and treatment, which can affect health of individuals. This dual perception of the phenomenon is partly related to a variety of terms and concepts used, that make difficult its theoretical and empirical approach. Harmonization of the definitions involved is required in order to make adequate epidemiological comparisons. Objectives: analyze the concept of self medication and related terms from the definitions in the literature of the subject. Conclusions: in the last four decades it has been an evolution of both the wording and the definitions related to self-medication, from a very simple concept that implies the absence of prescription, to more complex ones that encompass very diverse behaviors, even those mediated by an act of prescription but not followed or not completed by the patient. Additionally the conceptual proliferation seen, justify the ordering of the terms related to self-medication. This paper presents a proposal for classification in four groups: a. self-medication, b. self care, c. pharmaceutical preparations and medicines, and d. prescription. This proposal should facilitate the exploration and analysis of the phenomenon and allow future theoretical approaches.

Hematopoietic stem cells, overview and pathways implied on their self-renewal mechanisms

Blood tissue is composed approximately in 45% by cells and its derivatives, with a life span of around 120 days for erythrocytes and 3 years for certain type of lymphocytes. This lost is compensated with the hematopoietic system activity and the presence of an immature primitive cell population known as Hematopoietic Stem Cells (HSCs) which perform the hematopoiesis, a process that is active from the beginning of the fetal life and produces near to 2 x 1011 eritrocytes and 1010 white blood cells per day (1). Hematopoietic Stem Cells are capable of both self-renewal and differentiation into multiple lineages, are located in a particular niche and are identified by their own cell surface markers, as the CD34 antigen. Recently it has been possible to advance in the understanding of self-renewal, differentiation and proliferation processes and in the involvement of the signaling pathways Hedgehog, Notch and Wnt. Studying the influence of these mechanisms on in vivo and in vitro behavior and the basic biology of HSCs, has given valuable tools for the generation of alternative therapies for hematologic disorders as leukemias.