22 research outputs found

    Causes of genome instability: the effect of low dose chemical exposures in modern society.

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    Genome instability is a prerequisite for the development of cancer. It occurs when genome maintenance systems fail to safeguard the genome's integrity, whether as a consequence of inherited defects or induced via exposure to environmental agents (chemicals, biological agents and radiation). Thus, genome instability can be defined as an enhanced tendency for the genome to acquire mutations; ranging from changes to the nucleotide sequence to chromosomal gain, rearrangements or loss. This review raises the hypothesis that in addition to known human carcinogens, exposure to low dose of other chemicals present in our modern society could contribute to carcinogenesis by indirectly affecting genome stability. The selected chemicals with their mechanisms of action proposed to indirectly contribute to genome instability are: heavy metals (DNA repair, epigenetic modification, DNA damage signaling, telomere length), acrylamide (DNA repair, chromosome segregation), bisphenol A (epigenetic modification, DNA damage signaling, mitochondrial function, chromosome segregation), benomyl (chromosome segregation), quinones (epigenetic modification) and nano-sized particles (epigenetic pathways, mitochondrial function, chromosome segregation, telomere length). The purpose of this review is to describe the crucial aspects of genome instability, to outline the ways in which environmental chemicals can affect this cancer hallmark and to identify candidate chemicals for further study. The overall aim is to make scientists aware of the increasing need to unravel the underlying mechanisms via which chemicals at low doses can induce genome instability and thus promote carcinogenesis

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Violent Governance, Identity and the Production of Legitimacy: Autodefensas in Latin America

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    This article examines the intersections of violence, governance, identity and legitimacy in relation to autodefensas (self-defence groups) in Latin America, focusing on Mexico and Colombia. By shifting focus from the question of where legitimacy lies to how it is produced and contested by a range of groups, we challenge the often presumed link between the state and legitimacy. We develop the idea of a field of negotiation and contestation, firstly, to discuss and critique the concept of state failure as not merely a Western hegemonic claim but also a strategic means of producing legitimacy by autodefensas. Secondly, we employ and enrich the notion of violent pluralism to discuss the pervasiveness of violence and the role of neoliberalism, and to address the question of non-violent practices of governance. We argue that the idea of a field of contestation and negotiation helps to understand the complexity of relationships that encompass the production of legitimacy and identity through (non)violent governance, whereby lines between (non)state, (non)violence, and (il)legitimacy blur and transform. Yet, we do not simply dismiss (binary) distinctions as these continue to be employed by groups in their efforts to produce, justify, challenge, contest and negotiate their own and others’ legitimacy and identity

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Tracing the evolution within nearby galaxy groups: a multi-wavelength approach

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    none11Evolutionary scenarios suggest that several mechanisms (from inner secular evolution to accretion/merging) may transform galaxy members, driving groups from an active star forming phase to a more passive, typical of dense environments. We are investigating this transition in a nearby group sample, designed to cover a wide range of properties (see also Marino et al. (2010), Bettoni et al. (2011) and Marino et al. (2012)). We study two groups, USGC U268 and USGC U376 located in different regions of the Leo cloud, through a photometric and kinematic characterization of their member galaxies. We revisit the group membership, using results from recent red-shift surveys, and we investigate their substructures. U268, composed of 10 catalogued members and 11 new added members, has a small fraction (~24%) of early-type galaxies (ETGs). U376 has 16 plus 8 new added members, with ~38% of ETGs. We find the significant substructuring in both groups suggesting that they are likely accreting galaxies. U268 is located in a more loose environment than U376. For each member galaxy, broad band integrated and surface photometry have been obtained in far-UV (FUV) and near-UV (NUV) with GALEX, and in u, g, r, i, z (SDSS) bands. Halpha imaging and 2D high resolution kinematical data have been obtained using PUMA Scanning Fabry-Perot interferometer at the 2.12 m telescope in San Pedro Mártir (Baja California, México). We improved the galaxy classification and we detected morphological and kinematical distortions that may be connected to either on-going and/or past interaction/accretion events or environmental induced secular evolution. U268 appears more active than U376, with a large fraction of galaxies showing interaction signatures (60% vs. 13%). The presence of bars among late-type galaxies is ~10% in U268 and 29% in U376. The cumulative distribution of (FUV - NUV) colors of galaxies in U268 is significantly different (bluer) than that of U376's galaxies. Most (80%) of the early-type members in U376 inhabits the red sequence, a large fraction of galaxies, of different morphological types, are located in the green valley, while the blue sequence is under-populated with respect to U268.noneDaniela Bettoni;Antonina Marino;Roberto Rampazzo;Henri Plana;Margarita Rosado;Giuseppe Galletta;Paola Mazzei;Luciana Bianchi;Lucio M. Buson;Patricia Ambrocio-Cruz;Ruslan GabbasovBettoni, Daniela; Marino, Antonina; Roberto, Rampazzo; Henri, Plana; Margarita, Rosado; Galletta, Giuseppe; Paola, Mazzei; Luciana, Bianchi; Lucio M., Buson; Patricia Ambrocio, Cruz; Ruslan, Gabbaso

    L'économie des dévotions

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    Le présent livre cherche à élucider les rapports qu'entretiennent, à l'époque moderne, les activités économiques – en particulier commerçantes – et les pratiques dévotionnelles. Il s'agit de deux sphères volontiers séparées, avec en arrière-plan, des a priori d'incompatibilité, voire des aversions traditionnelles qui n'ont pas épargné l'historiographie. Et pourtant il est évident que, dans les sociétés d'Ancien Régime, le champ des pratiques de piété a constitué un facteur économique d'importance majeure, mais dont le poids précis reste autant à mesurer de façon différenciée que les attitudes commerçantes méritent d'être analysées avec précision. Quels sont les apports des agents de l'échange au fonctionnement économique des différents cultes et pratiques de dévotion ? Que se passe-t-il lorsque le religieux entre en conflit avec les intérêts économiques ? Comment décrire les formes de dévotion que cultivent les acteurs de l'échange eux-mêmes ? C'est autour de ces questions que le livre organise ses interrogations. Une première partie du livre prend pour objet l'économie des lieux de pèlerinage, une deuxième, quittant les sanctuaires de ce type, s'attache à analyser les conditions de production, les conjonctures et la logique distributive d'objets de dévotion plus largement diffusés. Une troisième section met l'accent sur les possibles tensions entre objectifs commerciaux et impératifs religieux ; la dernière s'interroge sur les dévotions des acteurs de l'échange
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