Fibrational induction rules for initial algebras

This paper provides an induction rule that can be used to prove properties of data structures whose types are inductive, i.e., are carriers of initial algebras of functors. Our results are semantic in nature and are inspired by Hermida and Jacobs’ elegant algebraic formulation of induction for polynomial data types. Our contribution is to derive, under slightly different assumptions, an induction rule that is generic over all inductive types, polynomial or not. Our induction rule is generic over the kinds of properties to be proved as well: like Hermida and Jacobs, we work in a general fibrational setting and so can accommodate very general notions of properties on inductive types rather than just those of particular syntactic forms. We establish the correctness of our generic induction rule by reducing induction to iteration. We show how our rule can be instantiated to give induction rules for the data types of rose trees, finite hereditary sets, and hyperfunctions. The former lies outside the scope of Hermida and Jacobs’ work because it is not polynomial; as far as we are aware, no induction rules have been known to exist for the latter two in a general fibrational framework. Our instantiation for hyperfunctions underscores the value of working in the general fibrational setting since this data type cannot be interpreted as a set

Attachment and substance use in adolescence: A review of conceptual and methodological aspects

Attachment is currently considered one of the major risk and/ or protective factors for substance use in adolescence. This paper reviews the most important studies published in the last 30 years in this field, focusing on the conceptual and methodological issues that may be making it more difficult to draw conclusions about the impact of attachment – especially attachment to parents – on substance use among youths. In general, the results indicate that secure attachment or stronger attachment between parents and children acts as a protective factor against drug use, even though there is a great variability in relation to the concept of addiction and its assessment. Secondly, most of the research reviewed also covers other factors that may be conditioning the influence of attachment to parents on children’s drug use and which would explain, at least in part, the disparity of the results from different studies. Notable among such factors would be individual characteristics (such as sex, age or self-esteem) and the influence of other sources of attachment, including peers and their circumstances (such as their drug use). Finally, we discuss the importance of taking into account the mentioned conceptual and methodological considerations aspects in research on attachment as a risk and/or protective factor for drug use in adolescence. El apego se considera actualmente uno de los mayores factores de riesgo y/o protección para el consumo de sustancias en la adolescencia. El presente trabajo revisa los estudios más importantes que se han publicado en los últimos 30 años al respecto, centrándose en aquellas cuestiones conceptuales y metodológicas que pueden estar dificultando concluir qué impacto ejerce el apego, sobre todo el apego a los padres, en el consumo de sustancias de los jóvenes. Los resultados indican, en general, que el apego seguro o un mayor apego entre padres e hijos actúa como factor de protección frente al consumo de drogas, si bien existe una gran variabilidad en torno al concepto de apego y su evaluación. En segundo lugar, la mayor parte de los estudios revisados incluyen además otros factores que pueden estar condicionando la influencia del apego a los padres en el consumo de drogas de los hijos y que explicarían, al menos en parte, la disparidad de los resultados en los distintos estudios. Entre estos factores destacarían las características individuales (como el sexo, la edad o la autoestima de los individuos), y la influencia de otras fuentes de apego, como los iguales y sus circunstancias, como por ejemplo el consumo de drogas por parte de éstos. Finalmente, se discute la importancia de tener en cuenta dichas consideraciones conceptuales y metodológicas en la investigación del apego como factor de riesgo y/o protección frente al consumo de drogas en la adolescencia

Biolaminóides Calcários Holocênicos: o Caso da Lagoa Vermelha, Brasil

Lagoa Vermelha lies within the coordinates 22°55’39” – 22°56’06” S and 42°21”29” – 42°24’13” W and is part of Araruama lagoon complex. Its dimensions are 4,400 m in length, 250 – 850 m in width, with approximate area of 2,400 m2 and 0,2 – 1,7 m in depth. The study was based on six monthly collections in five stations over the north – east lagoon’s margins from where was taken 20 samples of biolaminoids. To determinate the microbial composition of all different kinds of biolamonoids was made fresh and permanent slides and its analysis was carried out by microscopy. It was found three different kinds of microbial mats distributed throughout all five stations and were called: flat, polygonal and pustuled. Flat and polygonal microbial mats show itself layered, while pustuled show homogeneous structures. Layered and homogeneous ones present the same kind of main cyanobacterias, however layered mats in superficial stratum show preponderance of filamentous species and coccoid species in the bottom. Analysis showed a total of 33 species of cyanobacterias confirming it as main biolaminod component.The flat biolaminoid was mainly formed by Lyngbya aestuarii, the polygonal biolaminoid showed itself composed by Microcoleus chthonoplastes and the pustular biolaminoid was characterized by the presence of the cyanobacteria Chlorogoea tuberculosa. The cyanobacterial dominance is justified through its high morphologic adaptations that ensure its survival in many environments and prevail over in hipersaline local

Decreasing Sleep-Time Blood Pressure Determined by Ambulatory Monitoring Reduces Cardiovascular Risk

ObjectivesWe investigated whether reduced cardiovascular risk is more related to the progressive decrease of asleep or awake blood pressure.BackgroundIndependent studies have concluded that elevated sleep-time blood pressure is a better predictor of cardiovascular risk than awake or 24-h blood pressure means. However, the impact on cardiovascular risk of changes in these ambulatory blood pressure characteristics has not been properly investigated.MethodsWe prospectively studied 3,344 subjects (1,718 men and 1,626 women), 52.6 ± 14.5 years of age, during a median follow-up of 5.6 years. Those with hypertension at baseline were randomized to ingest all their prescribed hypertension medications upon awakening or ≥1 of them at bedtime. Blood pressure was measured for 48 h at baseline and again annually or more frequently (quarterly) if treatment adjustment was required.ResultsWith data collected at baseline, when asleep blood pressure was adjusted by awake mean, only the former was a significant predictor of outcome in a Cox proportional hazards model also adjusted for sex, age, and diabetes. Analyses of changes in ambulatory blood pressure during follow-up revealed a 17% reduction in cardiovascular risk for each 5-mm Hg decrease in asleep systolic blood pressure mean (p < 0.001), independently of changes in any other ambulatory blood pressure parameter.ConclusionsThe sleep-time blood pressure mean is the most significant prognostic marker of cardiovascular morbidity and mortality. Most importantly, the progressive decrease in asleep blood pressure, a novel therapeutic target that requires proper patient evaluation by ambulatory monitoring, was the most significant predictor of event-free survival. (Prognostic Value of Ambulatory Blood Pressure Monitoring in the Prediction of Cardiovascular Events and Effects of Chronotherapy in Relation to Risk [the MAPEC Study]; NCT00295542

El uso de recursos tecnológicos como forma de expresión cultural : ha encaminado a creadores y espectadores a tener una percepción alternativa de la realidad

El uso de recursos tecnológicos como forma de expresión cultural ha encaminado a creadores y espectadores a tener una percepción alternativa de la realida