Search

Abrumados por la acelerada proliferación de un cada vez mayor conjunto de formatos a través de los cuales, también los temas que ocupan a los historiadores de la arquitectura y el urbanismo, son sometidos a un proceso de escrutinio constante al servicio de la creación de contenido bajo parámetros de producción y rendimiento —una forma de conocimiento que anula el pensamiento, encontrándose la mayor parte de sus síntomas en la universidad—, uno no puede por menos de sentir cierto alivio al toparse con un libro, publicado con motivo de la celebración de un encuentro de investigación sobre historiografía de la arquitectura, que no sólo es capaz de cuestionar dicha rescisión desde su condición objetual —un único formato que funciona como una herramienta analógica de acción y que establece una relación entra autores y lectores (no consumidores)—, sino que lo hace, además, inquiriendo cuál sea la manera en que dicha historia ha sido y está siendo pensada.Es decir, no juzgando el pasado, sino interrogándolo, tal y como parece ser el objetivo de los historiadores de la arquitectura, toda vez que su trabajo ha alcanzado una autonomía que se justifica por el asentamiento de unos fundamentos epistemológicos propios.AbstractOverwhelmed by the proliferation of an increasing number of formats through which the themes that occupy historians of architecture and urban planning are also subject to constant scrutiny at the service of creating content controlled by parameters of production and performance — a form of knowledge that cancels thought, with its symptoms most prevalent in universities — one cannot help but feel a certain relief when coming across a book, published on the occasion of a research meeting on the historiography of architecture, that is not only capable of questioning this rescission objectively but also does so, inquiring what is the way in which this story has been and is being thought. It is a unique format that works as an analogue tool for action and that es

Disease emergence is accelerating in response to human activity-induced global changes. Understanding the mechanisms by which host populations can rapidly adapt to this threat will be crucial for developing future management practices. Pacific Oyster Mortality Syndrome (POMS) imposes a substantial and recurrent selective pressure on oyster populations (Crassostrea gigas). Rapid adaptation to this disease may arise through both genetic and epigenetic mechanisms. In this study, we used a combination of whole exome capture of bisulfite-converted DNA, next-generation sequencing, and (epi)genome-wide association mapping, to show that natural oyster populations differentially exposed to POMS displayed signatures of selection both in their genome (single nucleotide polymorphisms) and epigenome (CG-context DNA methylation). Consistent with higher resistance to POMS, the genes targeted by genetic and epigenetic variations were mainly related to host immunity. By combining correlation analyses, DNA methylation quantitative trait loci, and variance partitioning, we revealed that a third of the observed phenotypic variation was explained by interactions between the genetic sequence and epigenetic information, ∼14% by the genetic sequence, and up to 25% by the epigenome alone. Thus, as well as genetic adaptation, epigenetic mechanisms governing immune responses contribute significantly to the rapid adaptation of hosts to emerging infectious diseases.

Rearing density directly impacts fish welfare, which, in turn, affects productivity in aquaculture. Previous studies have indicated that high-density rearing during sexual development in fish can induce stress, resulting in a tendency towards male-biased sex ratios in the populations. In recent years, research has defined the relevance of the interactions between the environment and epigenetics playing a key role in the final phenotype. However, the underlying epigenetic mechanisms of individuals exposed to confinement remain elucidated. By using zebrafish (Danio rerio), the DNA methylation promotor region and the gene expression patterns of six genes, namely dnmt1, cyp19a1a, dmrt1, cyp11c1, hsd17b1, and hsd11b2, involved in the DNA maintenance methylation, reproduction, and stress were assessed. Zebrafish larvae were subjected to two high-density conditions (9 and 66 fish/L) during two periods of overlapping sex differentiation of this species (7 to 18 and 18 to 45 days post-fertilization, dpf). Results showed a significant masculinization in the populations of fish subjected to high densities from 18 to 45 dpf. In adulthood, the dnmt1 gene was differentially hypomethylated in ovaries and its expression was significantly downregulated in the testes of fish exposed to high-density. Further, the cyp19a1a gene showed downregulation of gene expression in the ovaries of fish subjected to elevated density, as previously observed in other studies. We proposed dnmt1 as a potential testicular epimarker and the expression of ovarian cyp19a1a as a potential biomarker for predicting stress originated from high densities during the early stages of development. These findings highlight the importance of rearing densities by long-lasting effects in adulthood conveying cautions for stocking protocols in fish hatcheries.

Abrumados por la acelerada proliferación de un cada vez mayor conjunto de formatos a través de los cuales, también los temas que ocupan a los historiadores de la arquitectura y el urbanismo, son sometidos a un proceso de escrutinio constante al servicio de la creación de contenido bajo parámetros de producción y rendimiento—una forma de conocimiento que anula el pensamiento, encontrándose la mayor parte de sus síntomas en la universidad—, uno no puede por menos de sentir cierto alivio al toparse con un libro, publicado con motivo de la celebración de un encuentro de investigación sobre historiografía de la arquitectura, que no sólo es capaz de cuestionar dicha rescisión desde su condición objetual —un único formato que funciona como una herramienta analógica de acción y que establece una relación entra autores y lectores (no consumidores)—, sino que lo hace, además, inquiriendo cuál sea la manera en que dicha historia ha sido y está siendo pensada.Es decir, no juzgando el pasado, sino interrogándolo, tal y como parece ser el objetivo de los historiadores de la arquitectura, toda vez que su trabajo ha alcanzado una autonomía que se justifica por el asentamiento de unos fundamentos epistemológicos propios.AbstractOverwhelmed by the proliferation of an increasing number of formats through which the themes that occupy historians of architecture and urban planning are also subject to constant scrutiny at the service of creating content controlled by parameters of production and performance — a form of knowledge that cancels thought, with its symptoms most prevalent in universities — one cannot help but feel a certain relief when coming across a book, published on the occasion of a research meeting on the historiography of architecture, that is not only capable of questioning this rescission objectively but also does so, inquiring what is the way in which this story has been and is being thought. It is a unique format that works as an analogue tool for action and that est

Rearing density directly impacts fish welfare, which, in turn, affects productivity in aquaculture. Previous studies have indicated that high-density rearing during sexual development in fish can induce stress, resulting in a tendency towards male-biased sex ratios in the populations. In recent years, research has defined the relevance of the interactions between the environment and epigenetics playing a key role in the final phenotype. However, the underlying epigenetic mechanisms of individuals exposed to confinement remain elucidated. By using zebrafish (Danio rerio), the DNA methylation promotor region and the gene expression patterns of six genes, namely dnmt1, cyp19a1a, dmrt1, cyp11c1, hsd17b1, and hsd11b2, involved in the DNA maintenance methylation, reproduction, and stress were assessed. Zebrafish larvae were subjected to two high-density conditions (9 and 66 fish/L) during two periods of overlapping sex differentiation of this species (7 to 18 and 18 to 45 days post-fertilization, dpf). Results showed a significant masculinization in the populations of fish subjected to high densities from 18 to 45 dpf. In adulthood, the dnmt1 gene was differentially hypomethylated in ovaries and its expression was significantly downregulated in the testes of fish exposed to high-density. Further, the cyp19a1a gene showed downregulation of gene expression in the ovaries of fish subjected to elevated density, as previously observed in other studies. We proposed dnmt1 as a potential testicular epimarker and the expression of ovarian cyp19a1a as a potential biomarker for predicting stress originated from high densities during the early stages of development. These findings highlight the importance of rearing densities by long-lasting effects in adulthood conveying cautions for stocking protocols in fish hatcheries.

The sex ratio is a key ecological demographic parameter crucial for population viability. However, the epigenetic mechanisms operating during gonadal development regulating gene expression and the sex ratio remain poorly understood. Moreover, there is interest in the development of epigenetic markers associated with a particular phenotype or as sentinels of environmental effects. Here, we profiled DNA methylation and gene expression of 10 key genes related to sex development and stress, including steroidogenic enzymes, and growth and transcription factors. We provide novel information on the sex-related differences and on the influence of elevated temperature on these genes in zebrafish, a species with mixed genetic and environmental influences on sex ratios. We identified both positive (e.g., amh, cyp11c and hsd11b2) and negative (e.g., cyp11a1 and dmrt1) correlations in unexposed males, and negative correlation (amh) in exposed females between DNA methylation and gene expression levels. Further, we combined DNA methylation analysis with machine learning procedures and found a series of informative CpGs capable not only of correctly identifying sex (based on cyp19a1a DNA methylation levels) but also of identifying whether males and females had been exposed to abnormally elevated temperature when young (based on amh and foxl2a DNA methylation levels, respectively). This was achieved in the absence of conspicuous morphological alterations of the gonads. These DNA methylation-based epigenetic biomarkers represent molecular resources that can correctly recapitulate past thermal history and pave the way for similar findings in other species to assess potential ecological effects of environmental disturbances in the context of climate change