211 resultados para Wood construction
Resumo:
Because of their beneficial impact on forest ecosystems, European red wood ants (Formica rufa group) are protected by law in many European countries and are considered to be among the most reliable bioindicators of forest stability. However, their taxonomy has been much debated and, unfortunately, it is too often neglected. This happens mainly because the morphology-based method for species delimitation requires lots of time and experience. We therefore employed 9 microsatellite loci and mitochondrial DNA (COI gene) to verify the power of genetic markers for red wood ant species delimitation and to investigate the cryptic diversity of these ants within the Eastern Swiss Alps. We analyzed 83 nests belonging to all red wood ant species that occur in the Swiss National Park area. Genetic data indicated that these species represent different genetic pools. Moreover, results showed that Formica aquilonia YARROW, 1955 and F. paralugubris SEIFERT, 1996 often hybridize within the Park, confirming that these two species are genetically very close and could have diverged only recently. Nevertheless, microsatellites also revealed that one entire population, located in the Minger Valley and morphologically identified as F. lugubris ZETTERSTEDT, 1838, is genetically different to all other analyzed F. lugubris populations found within the same area and to other red wood ant species. These findings, confirmed by mitochondrial DNA analyses, suggest the existence of a new cryptic species within the Eastern Swiss Alps. This putative cryptic species has been provisionally named F. lugubris-A2. These results have a great importance for future conservation plans, monitoring and evolutionary studies on these protected ants.
Resumo:
The aim of this article is to propose an anthropological point of view about informed consent in medicine. This quest for legitimacy should be read as a relational and social construction. In the heart of clinical complexity we find on one side various techniques employed by the medical community to validate research and to obtain the consent of patients. On the other side patients offer plural and subjective answers due to the doctor patient hierarchical and long relationship. Between constraints and freedoms, informed consent brings to light social relation.
Resumo:
Formica lugubris and E paralugubris are sympatric sibling species of wood ants, both of which are widely distributed in Switzerland. Until 1996 they were considered the same species, E lugubris. To investigate whether the two species can be distinguished based on discrimination cues used by the workers we used the pupa-carrying test first introduced by Rainer Rosengren. In this test workers of discriminator colonies are faced with two kinds of pupae and their preferences for one of the types are recorded based on differential retrieval. Interspecific comparisons showed that ants preferred conspecific worker pupae to those of the sibling species regardless whether the pupae were con-colonial or hetero-colonial. Hence, this test can be used as a taxonomic tool to identify wood ants hardly distinguishable by morphological characters. In intraspecific comparisons the highly polygynous (many queens per colony) E paralugubris, the polygynous form of E lugubris and the monogynous (single queen per nest) to weakly polygynous form of E lugubris expressed different trends in their preference behaviour (with nestmate recognition in 14%, 20% and 31% of replicates, respectively). Only F paralugubris presented no significant nestmate recognition.
Resumo:
Dans notre pratique auprès des adolescents engagés dans des agirs sexuels violents, la consommation de pornographie est fréquemment convoquée dans le parcours de ces sujets à la découverte de la sexualité. Si bien sûr, tous les adolescents qui visionnent ces images ne commettent pas de tels actes, ce constat préoccupant nous invite à nous interroger sur les effets ou plutôt les méfaits de la pornographie sur l'investissement du corps sexué et sur la construction de la sexualité. Outre une réflexion sur l'impact de l'image dans son caractère obscène et à la suite des travaux de G. Bonnet (2003, Le Défi à la pudeur. Quand la pornographie devient l'initiation sexuelle des jeunes), nous montrerons en quoi la pornographie constitue une forme de violence, parfois jusqu'au traumatisme. Ce danger auquel les adolescents sont (sur)exposés, notamment par le biais d'Internet, pourrait en effet favoriser un clivage (que nous retrouvons systématiquement dans la problématique des violences sexuelles) entre corps érotique et corps sexué. La consommation de pornographie s'apparenterait davantage à l'incorporation de la sexualité génitale marquant ainsi l'échec de l'introjection de la génitalité au moment de l'adolescence. Ne devient-elle pas alors un ersatz de la pulsion de mort ? en tant qu'elle isole le sujet dans une activité auto-pseudo-érotique, retirant à la sexualité sa fonction de lien et par là même ouvrant le champ au déchaînement de toutes formes de violence.
Resumo:
Social insects use multiple lines of collective defences to combat pathogens. One example of a behav- ioural group defence is the use of antimicrobial plant compounds to disinfect the nest. Indeed, wood ants collect coniferous tree resin, and the presence of resin in their nest protects them against fungal and bacterial pathogens. Many questions remain on the mechanisms of resin use, including which factors elicit resin collection and placement within nests. Here, we investigated whether the presence of brood induces Formica paralugubris workers to collect more resin, and whether the workers preferentially place resin near the brood. We also tested whether the collection and placement of resin depends on the presence of the fungal entomopathogen Beauveria bassiana. Workers brought more resin to their nest when brood was present, and preferentially placed the resin near the brood. In contrast, workers did not increase resin collection in response to exposure to B. bassiana, nor did they place resin closer to contaminated brood or contaminated areas of the nest. This lack of response may be explained by a limited effect of resin against the germination and growth of B. bassiana in vitro. Overall, our main result is that woods ants actively position resin near the brood, which probably confers prophylactic protection against other detrimental microorganisms.
Resumo:
Strepsirhines comprise 10 living or recently extinct families, ≥50% of extant primate families. Their phylogenetic relationships have been intensively studied, but common topologies have only recently emerged; e.g. all recent reconstructions link the Lepilemuridae and Cheirogaleidae. The position of the indriids, however, remains uncertain, and molecular studies have placed them as the sister to every clade except Daubentonia, the preferred sister group of morphologists. The node subtending Afro-Asian lorisids has been similarly elusive. We probed these phylogenetic inconsistencies using a test data set including 20 strepsirhine taxa and 2 outgroups represented by 3,543 mtDNA base pairs, and 43 selected morphological characters, subjecting the data to maximum parsimony, maximum likelihood and Bayesian inference analyses, and reconstructing topology and node ages jointly from the molecular data using relaxed molecular clock analyses. Our permutations yielded compatible but not identical evolutionary histories, and currently popular techniques seem unable to deal adequately with morphological data. We investigated the influence of morphological characters on tree topologies, and examined the effect of taxon sampling in two experiments: (1) we removed the molecular data only for 5 endangered Malagasy taxa to simulate 'extinction leaving a fossil record'; (2) we removed both the sequence and morphological data for these taxa. Topologies were affected more by the inclusion of morphological data only, indicating that palaeontological studies that involve inserting a partial morphological data set into a combined data matrix of extant species should be interpreted with caution. The gap of approximately 10 million years between the daubentoniid divergence and those of the other Malagasy families deserves more study. The apparently contemporaneous divergence of African and non-daubentoniid Malagasy families 40-30 million years ago may be related to regional plume-induced uplift followed by a global period of cooling and drying. © 2013 S. Karger AG, Basel.
Resumo:
Ce travail se situe au carrefour de la rhétorique, des théories de l'argumentation et de la linguistique du discours : il s'intéresse aux modalités diverses selon lesquelles une émotion peut être sémiotisée par un locuteur, et cela dans le cadre spécifique d'un discours de type argumentatif. Le questionnement vise à reprendre à nouveaux frais le concept rhétorique de pathos et porte, de façon générale, sur les rapports complexes qui unissent l'argumentation, d'une part, et l'émotion, d'autre part. L'hypothèse développée a trait à ce que l'on peut appeler l'argumentabilité des émotions. Les locuteurs ne font pas seulement « appel » à l'émotion dans le but d'accroître l'efficacité d'une argumentation visant à établir le bien-fondé d'une opinion ou l'opportunité d'une action : ils peuvent aussi, dans certains cas, chercher à argumenter pour ou contre l'émotion elle-même. Ils s'efforcent alors de formuler les raisons pour lesquelles il convient ou, au contraire, il ne convient pas d'éprouver cette émotion. La construction de l'émotion est dite « argumentative », dans le sens où l'émotion en vient à constituer l'objet même de l'argumentation : l'effort argumentatif des locuteurs porte moins sur des dispositions à croire et à agir que sur des dispositions à ressentir. Parler de l'« argumentabilité » des émotions, c'est insister sur le fait - essentiel, mais rarement relevé - que les émotions donnent elles aussi prise aux opérations argumentatives que l'on recense traditionnellement (mise en doute quant à la légitimité, justification ou, au contraire, tentative de réfutation). Ce travail ne vise pas seulement à apporter une contribution théorique aux études sur l'argumentation : il entend aussi mettre en pratique l'analyse argumentative sur un corpus de textes. Il s'agit des comptes-rendus écrits des principaux débats parlementaires français relatifs à l'abolition de la peine de mort (1791, 1848, 1908 et 1981). Bien qu'il s'échelonne sur une période de près de deux siècles, ce corpus présente une forte cohésion, dans la mesure où les textes qui le composent traitent d'un même thème et appartiennent à un même genre de discours. Cette cohésion est essentielle, dans la mesure où elle autorise une pratique raisonnée de la comparaison en diachronie : l'enjeu est de décrire l'évolution des stratégies argumentatives à travers le temps. Observé sur une longue durée, le pathos que développent les parlementaires favorables ou au contraire hostiles à l'abolition présente des visages multiples. On cherche à décrire aussi rigoureusement que possible la logique qui, lors de chaque débat, préside à la construction d'émotions comme la peur, la pitié, l'indignation ou encore la honte.
Resumo:
Since the advent of high-throughput DNA sequencing technologies, the ever-increasing rate at which genomes have been published has generated new challenges notably at the level of genome annotation. Even if gene predictors and annotation softwares are more and more efficient, the ultimate validation is still in the observation of predicted gene product( s). Mass-spectrometry based proteomics provides the necessary high throughput technology to show evidences of protein presence and, from the identified sequences, confirmation or invalidation of predicted annotations. We review here different strategies used to perform a MS-based proteogenomics experiment with a bottom-up approach. We start from the strengths and weaknesses of the different database construction strategies, based on different genomic information (whole genome, ORF, cDNA, EST or RNA-Seq data), which are then used for matching mass spectra to peptides and proteins. We also review the important points to be considered for a correct statistical assessment of the peptide identifications. Finally, we provide references for tools used to map and visualize the peptide identifications back to the original genomic information.