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As part of efforts to restore fishery resources and recover damaged coastal ecosystems, artificial reefs are often anchored on the seafloor in coastal zones, to provide new habitats for marine organisms. The aim of the study was to describe the structure of a community of benthic invertebrates colonising a niche-type artificial reef (AATN in Spanish). Nine structures were anchored at depths of 16 ± 1.5 m for 99 weeks (22 months) in the Area of Benthic Resource Management and Exploitation (AMERB) in coastal waters of the Region of Bio Bio, Chile. The results showed that, at 3 months from submersion of the NTAR, much of the artificial substrate remained bare and there were only low levels of specimens of Balanus sp. barnacles, showing mean coverage of 11.26%, and even lower proportions of Rhodophyta, with mean coverage of 0.34%. At 6 months, the presence of hydrozoans was seen, decreasing the coverage of the barnacles, which was aided further at 8 months with the arrival of barnacle predatory invertebrates. At 8 months, new benthic invertebrates appeared and competed for the substrate. These included sponges and algae. At 99 weeks, the hydrozoans dominated the substrate, followed by barnacles and Rhodophyta, the first colonising organisms, leading to colonisation by motile macro-invertebrates, mainly consisting of crustaceans, echinoderms and molluscs. The AATN artificial system provides an ideal substrate for the development of early ecological succession and the use of this technology should be feasible in the recovery process of habitat damaged by anthropogenic actions and climate change.

The red cusk-eel (Genypterus chilensis, Guichenot, 1848) is an iconic species in Chilean gastronomy, with a cultural significance that extends beyond its economic value, worthy of conservation. Despite the decline in fishery productivity across most of the distribution range for this species, little effort has been devoted to assessing stock management. In the present study, seven heterologous microsatellite loci (cmrGb3.8.1, cmrGb5.2B, cmrGb4.2A, cmrGb4.2B, cmrGb5.9, cmrGb4.11, and cmrGb2.6.1) were genotyped in a total of 153 individuals from four locations in central and southern Chile (30.5-37.6 • S), comprising ∼1,000 km of coastline. Five microsatellite loci were consistently amplified with a low frequency of null alleles (<2.5%). These markers showed high average heterozygosity (H O = 0.886 and H E = 0.884) and PIC (0.869). Significant genetic differentiation among locations (global F ST = 0.043, global D Jost = 0.252) suggested the presence of at least two genetic groups along the Chilean coast, with moderate levels of admixture between the two central populations (0.168 < Q mean < 0.822). The southern population showed no admixture with the central populations (Q mean = 0.985), less allelic richness and a small effective population size, indicating that urgent management measures must be developed for this fishery. The present study provides baseline information to assist fishery and aquaculture management and contribute to the recovery of declining populations.

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School violence theoretical research has been falling behind in the field of education research. An explanatory deficit emerges and therefore also theoretical, with certain reductionism and a proliferation of behavior measurement. This article focuses on the need of moving from a binary object that puts apart, sometimes in terms of opposition, the school from society, to an object of study with three dimensions: (i) different forms of violence produced by the school itself; (ii) different forms of violence that are reproduced at the school; (iii) different forms of violence that pass through the school. This triadic reformulation of the object of study is the result from a line of research and the review of indexed literature between 1990 and 2015.Key words: violence, school, problematic approach, dichotomy, triadic approach. ResumenLa dimensión teórica del estudio de la violencia escolar ha quedado rezagada en el campo de la investigación en educación. Se constata un déficit explicativo y en consecuencia de orden teórico, con ciertos reduccionismos y una proliferación de mediciones de conductas. En este artículo se plantea la necesidad de pasar de un objeto binario que separa, a veces en términos de oposición, la escuela de la sociedad a un objeto de estudio de tres dimensiones: (i) las violencias que produce la escuela; (ii) las violencias que se reproducen en la escuela; (iii) las violencias que cruzan la escuela. Esta reformulación tríadica del objeto de estudio es producto de una línea de investigación y de la revisión de la literatura indexada entre el año 1990 y 2015.Palabras clave: violencia, escuela, abordaje problemático, dicotomía, enfoque triádico.

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