163 research outputs found

    Linking vgll3 genotype and aggressive behaviour in juvenile Atlantic salmon (Salmo salar)

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    We tested the possibility that vgll3, a gene linked with maturation age in Atlantic salmon (Salmo salar), may be associated with behaviour by measuring aggressiveness and feeding activity in 380 juveniles with different vgll3 genotypes. Contrary to our prediction, individuals with the genotype associated with later maturation (vgll3*LL) were significantly more aggressive than individuals with the genotype associated with earlier maturation (vgll3*EE). Individuals with higher aggression were also significantly lighter in colour and had higher feeding activity. Although higher aggression was associated with higher feeding activity, there was no association between feeding activity and vgll3 genotype. Increased aggression of vgll3*LL individuals was independent of their sex and size, and genotypes did not differ in their condition factor. These results imply that aggressive behaviour may have an energetic cost impairing growth and condition, especially when food cannot be monopolized. This may have implications for individual fitness and aquaculture practices.Peer reviewe

    Properties of dust in the high-latitude translucent cloud L1780 I: Spatially distinct dust populations and increased dust emissivity from ISO observations

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    We have analyzed the properties of dust in the high galactic latitude translucent cloud Lynds 1780 using ISOPHOT maps at 100 and 200 micrometers and raster scans at 60, 80, 100, 120, 150 and 200 micrometers. In far-infrared (FIR) emission, the cloud has a single core that coincides with the maxima of visual extinction and 200um optical depth. At the resolution of 3.0 arcmin, the maximum visual extinction is 4.0 mag. At the cloud core, the minimum temperature and the maximum 200um optical depth are 14.9+/-0.4 K and 2.0+/-0.2x10^{-3}, respectively, at the resolution of 1.5 arcmin. The cloud mass is estimated to be 18M_{SUN}. The FIR observations, combined with IRAS observations, suggest the presence of different, spatially distinct dust grain populations in the cloud: the FIR core region is the realm of the "classical" large grains, whereas the very small grains and the PAHs have separate maxima on the Eastern side of the cold core, towards the "tail" of this cometary-shaped cloud. The color ratios indicate an overabundance of PAHs and VSGs in L1780. Our FIR observations combined with the optical extinction data indicate an increase of the emissivity of the big grain dust component in the cold core, suggesting grain coagulation or some other change in the properties of the large grains. Based on our observations, we also address the question, to what extent the 80um emission and even the 100um and the 120um emission contain a contribution from the small-grain component.Comment: 12 pages, 9 figures, minor changes, one table adde

    Far-infrared and molecular line observations of Lynds 183 - studies of cold gas and dust

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    We have mapped the dark cloud L183 in the far-infrared at 100um and 200um with the ISOPHOT photometer aboard the ISO satellite. The observations make it possible for the first time to study the properties of the large dust grains in L183 without confusion from smaller grains. The observations show clear colour temperature variations which are likely to be caused by changes in the emission properties of the dust particles. In the cloud core the far-infrared colour temperature drops below 12K. The data allow a new determination of the cloud mass and the mass distribution. The mass within a radius of 10 arcmin from the cloud centre is 25 Msun. We have mapped the cloud in several molecular lines including DCO+(2-1) and H13CO+(1-0). These species are believed to be tracers of cold and dense molecular material and we detect a strong anticorrelation between the DCO+ emission and the dust colour temperatures. In particular, the DCO+(2-1) emission is not detected towards the maximum of the 100um emission where the colour temperature rises above 15K. The H13CO+ emission follows the DCO+ distribution but CO isotopes show strong emission even towards the 100um peak. A comparison of the DCO+ and C18O maps shows sharp variations in the relative intensities of the species. Morphologically the 200um dust emission traces the distribution of dense molecular material as seen e.g. in C18O lines. A comparison with dust column density shows that C18O is depleted by a factor of 1.5 in the cloud core. We present results of R- and B-band starcounts. The extinction is much better correlated with the 200um than with the 100um emission. Based on the 200um correlation at low extinction values we deduce a value of ~17mag for the visual extinction towards the cloud centre.Comment: to be published in A&

    Water and ammonia abundances in S140 with the Odin satellite

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    We have used the Odin satellite to obtain strip maps of the ground-state rotational transitions of ortho-water and ortho-ammonia, as well as CO(5-4) and 13CO(5-4) across the PDR, and H218O in the central position. A physi-chemical inhomogeneous PDR model was used to compute the temperature and abundance distributions for water, ammonia and CO. A multi-zone escape probability method then calculated the level populations and intensity distributions. These results are compared to a homogeneous model computed with an enhanced version of the RADEX code. H2O, NH3 and 13CO show emission from an extended PDR with a narrow line width of ~3 kms. Like CO, the water line profile is dominated by outflow emission, however, mainly in the red wing. The PDR model suggests that the water emission mainly arises from the surfaces of optically thick, high density clumps with n(H2)>10^6 cm^-3 and a clump water abundance, with respect to H2, of 5x10^-8. The mean water abundance in the PDR is 5x10^-9, and between ~2x10^-8 -- 2x10^-7 in the outflow derived from a simple two-level approximation. Ammonia is also observed in the extended clumpy PDR, likely from the same high density and warm clumps as water. The average ammonia abundance is about the same as for water: 4x10^-9 and 8x10^-9 given by the PDR model and RADEX, respectively. The similarity of water and ammonia PDR emission is also seen in the almost identical line profiles observed close to the bright rim. Around the central position, ammonia also shows some outflow emission although weaker than water in the red wing. Predictions of the H2O(110-101) and (111-000) antenna temperatures across the PDR are estimated with our PDR model for the forthcoming observations with the Herschel Space Observatory.Comment: 13 pages, 14 figures, 10 tables. Accepted for publication in Astronomy & Astrophysics 14 November 200

    The design and function of birds’ nests

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    All birds construct nests in which to lay eggs and/or raise offspring. Traditionally, it was thought that natural selection and the requirement to minimize the risk of predation determined the design of completed nests. However, it is becoming increasingly apparent that sexual selection also influences nest design. This is an important development as while species such as bowerbirds build structures that are extended phenotypic signals whose sole purpose is to attract a mate, nests contain eggs and/or offspring, thereby suggesting a direct tradeoff between the conflicting requirements of natural and sexual selection. Nest design also varies adaptively in order to both minimize the detrimental effects of parasites and to create a suitable microclimate for parents and developing offspring in relation to predictable variation in environmental conditions. Our understanding of the design and function of birds’ nests has increased considerably in recent years, and the evidence suggests that nests have four nonmutually exclusive functions. Consequently, we conclude that the design of birds’ nests is far more sophisticated than previously realized and that nests are multifunctional structures that have important fitness consequences for the builder/s

    First NH3 detection of the Orion Bar

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    Odin has successfully observed three regions in the Orion A cloud, i.e. Ori KL, Ori S and the Orion Bar, in the 572.5 GHz rotational ground state line of ammonia, ortho-NH3 (J,K) = (1,0) -> (0,0), and the result for the Orion Bar represents the first detection in an ammonia line. Several velocity components are present in the data. Specifically, the observed line profile from the Orion Bar can be decomposed into two components, which are in agreement with observations in high-J CO lines by Wilson et al. 2001. Using the source model for the Orion Bar by these authors, our Odin observation implies a total ammonia abundance of NH3/H2 = 5E-9.Comment: 4 pages with 2 figures, accepted for publication in A&

    De-Novo Transcriptome Sequencing of a Normalized cDNA Pool from Influenza Infected Ferrets

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    The ferret is commonly used as a model for studies of infectious diseases. The genomic sequence of this animal model is not yet characterized, and only a limited number of fully annotated cDNAs are currently available in GenBank. The majority of genes involved in innate or adaptive immune response are still lacking, restricting molecular genetic analysis of host response in the ferret model. To enable de novo identification of transcriptionally active ferret genes in response to infection, we performed de-novo transcriptome sequencing of animals infected with H1N1 A/California/07/2009. We also included splenocytes induced with bacterial lipopolysaccharide to allow for identification of transcripts specifically induced by Gram-negative bacteria. We pooled and normalized the cDNA library in order to delimit the risk of sequencing only highly expressed genes. While normalization of the cDNA library removes the possibility of assessing expression changes between individual animals, it has been shown to increase identification of low abundant transcripts. In this study, we identified more than 19000 partial ferret transcripts, including more than 1000 gene orthologs known to be involved in the innate and the adaptive immune response

    Intradermal Electroporation of Naked Replicon RNA Elicits Strong Immune Responses

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    RNA-based vaccines represent an interesting immunization modality, but suffer from poor stability and a lack of efficient and clinically feasible delivery technologies. This study evaluates the immunogenic potential of naked in vitro transcribed Semliki Forest virus replicon RNA (RREP) delivered intradermally in combination with electroporation. Replicon-immunized mice showed a strong cellular and humoral response, contrary to mice immunized with regular mRNA. RREP-elicited induction of interferon-γ secreting CD8+ T cells and antibody responses were significantly increased by electroporation. CD8+ T cell responses remained substantial five weeks post vaccination, and antigen-specific CD8+ T cells with phenotypic characteristics of both effector and central memory cells were identified. The immune response during the contraction phase was further increased by a booster immunization, and the proportion of effector memory cells increased significantly. These results demonstrate that naked RREP delivered via intradermal electroporation constitute an immunogenic, safe and attractive alternative immunization strategy to DNA-based vaccines

    Protective Efficacy of Serially Up-Ranked Subdominant CD8+ T Cell Epitopes against Virus Challenges

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    Immunodominance in T cell responses to complex antigens like viruses is still incompletely understood. Some data indicate that the dominant responses to viruses are not necessarily the most protective, while other data imply that dominant responses are the most important. The issue is of considerable importance to the rational design of vaccines, particularly against variable escaping viruses like human immunodeficiency virus type 1 and hepatitis C virus. Here, we showed that sequential inactivation of dominant epitopes up-ranks the remaining subdominant determinants. Importantly, we demonstrated that subdominant epitopes can induce robust responses and protect against whole viruses if they are allowed at least once in the vaccination regimen to locally or temporally dominate T cell induction. Therefore, refocusing T cell immune responses away from highly variable determinants recognized during natural virus infection towards subdominant, but conserved regions is possible and merits evaluation in humans

    Unknown cadaver: its historical and academic importance for human anatomy

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    Observações feitas na maioria das universidades brasileiras estrangeiras, e, inclusive, em algumas sobre o aspecto acadêmico do uso de cadáveres humanos como principal material que suporta e direciona a Anatomia Humana nos cursos da área da saúde, traz, dentre outras conclusões de caráter didático, uma questão de formação, muito mais importante do que uma simples questão de, apenas, informação universitária. Há de se concordar que, mesmo com o fabuloso avanço tecnológico e suas possibilidades, nossas universidades hoje, primam mais pela questão informativa do que propriamente pela formativa, ao passo que ternos consciência de que o ser humano necessita igualmente de ambas. Em consequência disto, o principal objetivo deste trabalho é enfocar o valor acadêmico do cadáver, evidenciando sua importante relação histórica, sem a qual a Anatomia não existiria e, certamente, a Medicina também não teria ultrapassado suas fronteiras limitadas do passado. O fato de ser este um trabalho realizado em uma universidade brasileira é revestido de responsabilidade e determinação em tentar colocar a figura do cadáver humano no lugar, no qual ele realmente deva estar, não apenas como simples material e instrumento de ensino da anatomia, mas também como lição de vida através da morte, criando Ciência e Arte, valorizando sua importância no contexto artístico e religioso, fatores estes imprescindíveis para a formação sócio-cultural humana. Por outro lado, este estudo com abordagem de caráter acadêmico, tornou-se dificil quanto a bibliografia específica, tendo sido feita portanto, quase toda a sua pesquisa em tratados históricos e anatômicos e, apenas alguns poucos trabalhos sobre a importância do cadáver para a Anatomia. Neste trabalho, procuramos usar ilustrações e figuras como documentação de caráter informativo e estético. Assim sendo, para uma abordagem mais ampla, o cadáver foi discutido desde sua relação histórica e acadêmica, até os dias de hoje, onde ainda se enfrenta, quase, as mesmas dificuldades do passado, no que diz respeito as questões de doação de corpo e órgãos, que deixaram de ser apenas institucionalmente acadêmicas, para ser mais rigorosamente sociais, segundo as Leis vigentes.Observations about most of brazilian universities and, even some of foreign ones, concerning the academic aspects of the use of human cadavers or corpses as the principal human anatomy method of studying, which maintain the basic courses of Health Sciences Field, that is, the cadaver or corpse himself should be also seen as a noble and magnificent way of transmitting knowledge and human values. Indeed, these observations have been showing some didactic results concerning much more, a matter of individual information than individual formation itself. Nowadays, this happens because scholasticism, differently from the past, seems to emphasize quantitative rather than qualitative teaching philosophy. We must admit that, even living in a technological era and being able to take advantages of its possibilities, our universities today emphasize much more the information itself than individual formation of our professionals of tomorrow, while we know that the individual needs both, equally. Therefore, the main goal of this work is focusing the academic importance of the human cadaver or corpse as a practical studying material, which is related to the own history of the practical Anatomy and consequently Medicine and, if it were not because of that, Medicine itself would not have gone beyond its limited frontiers of the past. On the other hand, the inedited academic meaning of this work became too difficult to come abroad, because of its specific bibliographical lack among scientific publications and, that's why, most of its text was found in the old Health Sciences, books and texts in general. However, another particular characteristic of this work is the great number of pictures and illustrations, which enrich the present text and substitute the lack of similar works' bibliography, In this work, the corpse is seen, from his historical relation and academical aspects the to present circumstances, where the need for anatomical study faces the same difficulties of the past, when Vesalius opened the way to the study of Human Anatomy, but as we know many years passed before Anatomy could be taught to medical students by means of dissection, the only method by which physicians and surgeons can fully acquire this knowledge. The scarcity of anatomical material seemed to be over at the present time, when laws were just enacted, such as specified law for the use of the corpse, organs and structures donation, that unfortunately did not solve the old and permanent problem, such as the absence of corpses for anatomical dissections.BV UNIFESP: Teses e dissertaçõe
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