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Cartographie des émotions

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ISBN: 9782878545920 9782878549638 Year: Language: French
Publisher: Presses Sorbonne Nouvelle
Added to DOAB on : 2017-11-23 16:18:13
License: OpenEdition licence for Books

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Ce volume étudie les différents liens entre langues et émotions que ce soit dans les commentaires sportifs, les textes classiques ou les films. Les contributions ici réunies proposent une définition et une catégorisation des affects afin de mieux comprendre les enjeux linguistiques et sociolinguistiques de l’expression des émotions. This volume studies the different links between languages and emotions, whether in sports commentary, classical texts or films. The contributions gathered here p...

Quantitative Assessment and Validation of Network Inference Methods in Bioinformatics

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889194780 Year: Pages: 191 DOI: 10.3389/978-2-88919-478-0 Language: English
Publisher: Frontiers Media SA
Subject: Biotechnology --- General and Civil Engineering --- Genetics --- Science (General)
Added to DOAB on : 2016-03-10 08:14:33
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Scientists today have access to an unprecedented arsenal of high-tech tools that can be used to thoroughly characterize biological systems of interest. High-throughput “omics” technologies enable to generate enormous quantities of data at the DNA, RNA, epigenetic and proteomic levels. One of the major challenges of the post-genomic era is to extract functional information by integrating such heterogeneous high-throughput genomic data. This is not a trivial task as we are increasingly coming to understand that it is not individual genes, but rather biological pathways and networks that drive an organism’s response to environmental factors and the development of its particular phenotype. In order to fully understand the way in which these networks interact (or fail to do so) in specific states (disease for instance), we must learn both, the structure of the underlying networks and the rules that govern their behavior. In recent years there has been an increasing interest in methods that aim to infer biological networks. These methods enable the opportunity for better understanding the interactions between genomic features and the overall structure and behavior of the underlying networks. So far, such network models have been mainly used to identify and validate new interactions between genes of interest. But ultimately, one could use these networks to predict large-scale effects of perturbations, such as treatment by multiple targeted drugs. However, currently, we are still at an early stage of comprehending methods and approaches providing a robust statistical framework to quantitatively assess the quality of network inference and its predictive potential. The scope of this Research Topic in Bioinformatics and Computational Biology aims at addressing these issues by investigating the various, complementary approaches to quantify the quality of network models. These “validation” techniques could focus on assessing quality of specific interactions, global and local structures, and predictive ability of network models. These methods could rely exclusively on in silico evaluation procedures or they could be coupled with novel experimental designs to generate the biological data necessary to properly validate inferred networks.

Liberté / Libertés

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ISBN: 9782869064706 Year: Language: French
Publisher: Presses universitaires François-Rabelais
Added to DOAB on : 2017-07-04 12:27:07
License: OpenEdition licence for Books

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« Liberté » : concept exaltant et souvent exalté dont l'évidence semble absolue mais qui se décline différemment selon les cultures nationales ou selon que le locuteur est historien, juriste, philosophe ou homme de la rue. Revendiquée par toutes les civilisations occidentales, l'idée de liberté se révèle protéiforme à l'infini mais contingente, modelée par l'époque et les circonstances, et souvent limitée par ses incertitudes. Si on peut vouloir mourir pour la liberté, on sait rarement quel e...

Comparative studies between HTLV-1 and HTLV-2 function and pathobiology

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889194988 Year: Pages: 94 DOI: 10.3389/978-2-88919-498-8 Language: English
Publisher: Frontiers Media SA
Subject: Microbiology --- Science (General)
Added to DOAB on : 2015-11-16 15:44:59
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Human T-cell leukemia viruses type 1 and 2 (HTLV-1 and HTLV-2) share a common genetic organization, expression strategy and ability to infect and immortalize T-cells in vitro; however, HTLV-1 and HTLV-2 are strikingly different in terms of clinical impact. HTLV-1 is recognized as the aetiological agent of adult T-cell leukemia/lymphoma (ATLL), and HTLV-associated myeolopathy/tropical spastic paraparesis (HAM/TSP), in contrast, HTLV-2 does not cause hematologic disorders and is only sporadically associated with cases of subacute myelopathy. HTLV-1 and HTLV-2 also exhibit distinct cellular tropisms in vivo: HTLV-1 is mainly found in CD4+T lymphocytes, whereas CD8+T-cells are the preferred target for HTLV-2. The articles contributed in this Research Topic are covering all the different aspects that characterize HTLV-1 and HTLV-2, by highlighting differences in their biology that might provide clues to their distinct pathogenic properties.

Keywords

HTLV-1 --- HTLV-2 --- Expression --- Proteins --- Co-infection

Plastid Proteostasis: Relevance of Transcription; Translation and Post-Translational Modifications

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889453436 Year: Pages: 110 DOI: 10.3389/978-2-88945-343-6 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Botany
Added to DOAB on : 2018-02-27 16:16:45
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Due to their bacterial endosymbiotic origin plastids are organelles with both nuclear-encoded and plastid-encoded proteins. Therefore, a highly integrated modulation of gene expression between the nucleus and the plastome is needed in plant cell development. Plastids have retained for the most part a prokaryotic gene expression machinery but, differently from prokaryotes and eukaryotes, they have largely abandoned transcriptional control and switched to predominantly translational control of their gene expression. Some transcriptional regulation is known to occur, but the coordinate expression between the nucleus and the plastome takes place mainly through translational regulation. However, the regulatory mechanisms of plastid gene expression (PGE) are mediated by intricate plastid-nuclear interactions and are still far from being fully understood. Although, for example, translational autoregulation mechanisms in algae have been described for subunits of heteromeric protein complexes and termed control by epistasy of synthesis (CES), only few autoregulatory proteins have been identified in plant plastids. It should be noted of course that PGE in C. reinhardtii is different from that in plants in many aspects. Another example of investigation in this research area is to understand the interactions that occur during RNA binding between nucleus-encoded RNA-binding proteins and the respective RNA sequences, and how this influences the translation initiation process. In addition to this, the plastid retains a whole series of mechanisms for the preservation of its protein balance (proteostasis), including specific proteases, as well as molecular chaperones and enzymes useful in protein folding. After synthesis, plastid proteins must rapidly fold into stable three dimensional structures and often undergo co- and posttranslational modifications to perform their biological mission, avoiding aberrant folding, aggregation and targeting with the help of molecular chaperones and proteases. We believe that this topic is highly interesting for many research areas because the regulation of PGE is not only of wide interest for plant biologists but has also biotechnological implications. Indeed, plastid transformation turns out to be a very promising tool for the production of recombinant proteins in plants, yet some limitations must still be overcome and we believe that this is mainly due to our limited knowledge of the mechanisms in plastids influencing the maintenance of proteostasis.

Synthetic Biology: Engineering complexity and refactoring cell capabilities

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889196852 Year: Pages: 123 DOI: 10.3389/978-2-88919-685-2 Language: English
Publisher: Frontiers Media SA
Subject: Biotechnology --- General and Civil Engineering
Added to DOAB on : 2015-10-30 16:33:44
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One of the key features of biological systems is complexity, where the behavior of high level structures is more than the sum of the direct interactions between single components. Synthetic Biologists aim to use rational design to build new systems that do not already exist in nature and that exhibit useful biological functions with different levels of complexity. One such case is metabolic engineering, where, with the advent of genetic and protein engineering, by supplying cells with chemically synthesized non-natural amino acids and sugars as new building blocks, it is now becoming feasible to introduce novel physical and chemical functions and properties into biological entities. The rules of how complex behaviors arise, however, are not yet well understood. For instance, instead of considering cells as inert chassis in which synthetic devices could be easily operated to impart new functions, the presence of these systems may impact cell physiology with reported effects on transcription, translation, metabolic fitness and optimal resource allocation. The result of these changes in the chassis may be failure of the synthetic device, unexpected or reduced device behavior, or perhaps a more permissive environment in which the synthetic device is allowed to function. While new efforts have already been made to increase standardization and characterization of biological components in order to have well known parts as building blocks for the construction of more complex devices, also new strategies are emerging to better understand the biological dynamics underlying the phenomena we observe. For example, it has been shown that the features of single biological components [i.e. promoter strength, ribosome binding affinity, etc] change depending on the context where the sequences are allocated. Thus, new technical approaches have been adopted to preserve single components activity, as genomic insulation or the utilization of prediction algorithms able to take biological context into account. There have been noteworthy advances for synthetic biology in clinical technologies, biofuel production, and pharmaceuticals production; also, metabolic engineering combined with microbial selection/adaptation and fermentation processes allowed to make remarkable progress towards bio-products formation such as bioethanol, succinate, malate and, more interestingly, heterologous products or even non-natural metabolites. However, despite the many progresses, it is still clear that ad hoc trial and error predominates over purely bottom-up, rational design approaches in the synthetic biology community. In this scenario, modelling approaches are often used as a descriptive tool rather than for the prediction of complex behaviors. The initial confidence on a pure reductionist approach to the biological world has left space to a new and deeper investigation of the complexity of biological processes to gain new insights and broaden the categories of synthetic biology. In this Research Topic we host contributions that explore and address two areas of Synthetic Biology at the intersection between rational design and natural complexity: (1) the impact of synthetic devices on the host cell, or "chassis" and (2) the impact of context on the synthetic devices. Particular attention will be given to the application of these principles to the rewiring of cell metabolism in a bottom-up fashion to produce non-natural metabolites or chemicals that should eventually serve as a substitute for petrol-derived chemicals, and, on a long-term view, to provide economical, ecological and ethical solutions to today’s energetic and societal challenges.

Cellular and molecular mechanisms of motor neuron death in amyotrophic lateral sclerosis

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889193769 Year: Pages: 190 DOI: 10.3389/978-2-88919-376-9 Language: English
Publisher: Frontiers Media SA
Subject: Neurology --- Science (General)
Added to DOAB on : 2015-11-19 16:29:12
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Amyotrophic lateral sclerosis (ALS), which was described since 1869 by Jean Martin Charcot, is a devastating neurodegenerative disease characterized by the selective and progressive loss of upper and lower motor neurons of the cerebral cortex, brainstem and the spinal cord. The cognitive process is not affected and is not merely the result of aging because may occur at young ages. The only known cause of the disease is associated with genetic mutations, mainly in the gene encoding superoxide dismutase 1 (familial ALS), whereas there is no known cause of the sporadic form of ALS (SALS), which comprises >90% of cases. Both ALS types develop similar histopathological and clinical characteristics, and there is no treatment or prevention of the disease. Because effective treatments for ALS, as for other neurodegenerative diseases, can only result from the knowledge of their cellular and molecular pathophysiological mechanisms, research on such mechanisms is essential. Although progress in neurochemical, physiological and clinical investigations in the last decades has identified several mechanisms that seem to be involved in the cell death process, such as glutamate-mediated excitotoxicity, alterations of inhibitory circuits, inflammatory events, axonal transport deficits, oxidative stress, mitochondrial dysfunction and energy failure, the understanding of the origin and temporal progress of the disease is still incomplete and insufficient. Clearly, there is a need of further experimental models and approaches to discern the importance of such mechanisms and to discover the factors that determine the selective death of motor neurons characteristic of ALS, in contrast to other neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease. Whereas studies in vitro in cell cultures, tissue slices or organotypic preparations can give useful information regarding cellular and molecular mechanisms, the experiments in living animal models obviously reflect more closely the situation in the human disease, provided that the symptoms and their development during time mimics as close as possible those of the human disease. It is necessary to correlate the experimental findings in vitro with those in vivo, as well as those obtained in genetic models with those in non-genetic models, aiming at designing and testing therapeutic strategies based on the results obtained.

Functional Characterization of Insect Chemoreceptors: Receptivity Range, Expression and Evolution

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889198603 Year: Pages: 163 DOI: 10.3389/978-2-88919-860-3 Language: English
Publisher: Frontiers Media SA
Subject: Ecology --- Science (General)
Added to DOAB on : 2016-01-19 14:05:46
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Olfaction and taste are of critical importance to insects and other animals, since vital behaviours, including mate, food and host seeking, as well as predator and toxin avoidance, are guided by chemosensory cues. Mate and habitat choice are to a large extent determined by chemical signals, and chemoreceptors contribute accordingly to pre-mating isolation barriers and speciation. In addition to fundamental physiological, ecological and evolutionary consideration, the knowledge of insect taste and especially olfaction is also of great importance to human economies, since it facilitates a more informed approach to the management of insect pests of agricultural crops and forests, and insect vectors of disease. Chemoreceptors, which bind to external chemical signals and then transform and send the sensory information to the brain, are at the core of the peripheral olfactory and gustatory system and have thus been the focus of recent research in chemical ecology. Specifically, emphasis has been placed on functional characterization of olfactory receptor genes, which are derived from three large gene families, namely the odorant receptors, gustatory receptors and ionotropic receptors. Spatial expression patterns of olfactory receptors in diverse chemosensory tissues provide information on divergent functions, with regards to ecologically relevant behaviours. On the other hand, characterization of olfactory receptor activation profiles, or “deorphanization”, provides complimentary data on the molecular range of receptivity to the fundamental unit of the olfactory sense. The aim of this Research Topic is to give an update on the breadth and depth of research currently in progress related to understanding the molecular mechanisms of insect chemoreception, with specific emphasis on the olfactory receptors.

The Social Nature of Emotions

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889199099 Year: Pages: 220 DOI: 10.3389/978-2-88919-909-9 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Psychology
Added to DOAB on : 2016-01-19 14:05:46
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Emotion is a defining aspect of the human condition. Emotions pervade our social and professional lives, they affect our thinking and behavior, and they profoundly shape our relationships and social interactions. Emotions have traditionally been conceptualized and studied as individual phenomena, with research focusing on cognitive and expressive components and on physiological and neurological processes underlying emotional reactions. Over the last two decades, however, an increasing scholarly awareness has emerged that emotions are inherently social – that is, they tend to be elicited by other people, expressed at other people, and regulated to influence other people or to comply with social norms (Fischer & Manstead, 2008; Keltner & Haidt, 1999; Parkinson, 1996; Van Kleef, 2009). Despite this increasing awareness, the inclusion of the social dimension as a fundamental element in emotion research is still in its infancy (Fischer & Van Kleef, 2010). We therefore organized this special Research Topic on the social nature of emotions to review the state of the art in research and methodology and to stimulate theorizing and future research. The emerging field of research into the social nature of emotions has focused on three broad sets of questions. The first set of questions pertains to how social-contextual factors shape the experience, regulation, and expression of emotions. Studies have shown, for instance, that the social context influences the emotions people feel and express (Clark, Fitness, & Brissette, 2004; Doosje, Branscombe, Spears, & Manstead, 2004; Fischer & Evers, 2011). The second set of questions concerns social-contextual influences on the recognition and interpretation of emotional expressions. Studies have shown that facial expressions are interpreted quite differently depending on the social context (e.g., in terms of status, culture, or gender) in which they are expressed (Elfenbein & Ambady, 2002; Hess & Fischer, 2013; Mesquita & Markus, 2004; Tiedens, 2001). The third set of questions has to do with the ways in which people respond to the emotional expressions of others, and how such responses are shaped by the social context. Studies have shown that emotional expressions can influence the behavior of others, for instance in group settings (Barsade, 2002; Cheshin, Rafaeli & Bos, 2011; Heerdink, Van Kleef, Homan, & Fischer, 2013), negotiations (Sinaceur & Tiedens, 2006; Van Kleef, De Dreu, & Manstead, 2004), and leadership (Sy, Côté, & Saavedra, 2005; Van Kleef, Homan, Beersma, & Van Knippenberg, 2010). This Research Topic centers around these and related questions regarding the social nature of emotions, thereby highlighting new research opportunities and guiding future directions in the field. We bring together a collection of papers to provide an encyclopedic, open-access snapshot of the current state of the art of theorizing and research on the social nature of emotion. The state of the art work that is presented in this e-book helps advance the understanding of the social nature of emotions. It brings together the latest cutting-edge findings and thoughts on this central topic in emotion science, as it heads toward the next frontier.

Protein Solubility and Aggregation in Bacteria

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889199761 Year: Pages: 127 DOI: 10.3389/978-2-88919-976-1 Language: English
Publisher: Frontiers Media SA
Subject: Science (General) --- Microbiology
Added to DOAB on : 2016-01-19 14:05:46
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Proteins suffer many conformational changes and interactions through their life, from their synthesis at ribosomes to their controlled degradation. Only folded and soluble proteins are functional. Thus, protein folding and solubility are controlled genetically, transcriptionally, and at the protein sequence level. In addition, a well-conserved cellular machinery assists the folding of polypeptides to avoid misfolding and ensure the attainment of soluble and functional structures. When these redundant protective strategies are overcome, misfolded proteins are recruited into aggregates. Recombinant protein production is an essential tool for the biotechnology industry and also supports expanding areas of basic and biomedical research, including structural genomics and proteomics. Although bacteria still represent a convenient production system, many recombinant polypeptides produced in prokaryotic hosts undergo irregular or incomplete folding processes that usually result in their accumulation as insoluble aggregates, narrowing thus the spectrum of protein-based drugs that are available in the biotechnology market. In fact, the solubility of bacterially produced proteins is of major concern in production processes, and many orthogonal strategies have been exploited to try to increase soluble protein yields. Importantly, contrary to the usual assumption that the bacterial aggregates formed during protein production are totally inactive, the presence of a fraction of molecules in a native-like structure in these assemblies endorse them with a certain degree of biological activity, a property that is allowing the use of bacteria as factories to produce new functional materials and catalysts. The protein embedded in intracellular bacterial deposits might display different conformations, but they are usually enriched in beta-sheet-rich assemblies resembling the amyloid fibrils characteristic of several human neurodegenerative diseases. This makes bacterial cells simple, but biologically relevant model systems to address the mechanisms behind amyloid formation and the cellular impact of protein aggregates. Interestingly, bacteria also exploit the structural principles behind amyloid formation for functional purposes such as adhesion or cytotoxicity. In the present research topic we collect papers addressing all the issues mentioned above from both the experimental and computational point of view.

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