418 research outputs found

    Rationalité, relativisme, évolution sociale: une analyse critique du modèle cognitiviste de Boudon-Weber

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    This essay mainly concerns the foundation of a method of inquiry appropriate to the study of social reality. It starts from a criticism of Boudon-Weber's cognitivist method, the lacks of which seem particularly qualified for underlining the methodologic difficulties afflicting social thought. These lacks helps us to point out the reason and potentialities of our proposal on method that may be denominated 'social objectivism'. This proposal suggests additional objections both to Weber's cultural relativism and Boudon's anti-relativism, as well as to the notion of rationality and the theory of social evolution developed by those authors. A different notion of rationality is proposed and an alternative explanation of social process, referable both to the evolution and organization of human societies, is sketched out that may also be extended to the interpretation of historical processes

    Passive mode locking of a Tm,Ho:KY(WO4)(2) laser around 2 μm

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    We report the first demonstration, to our knowledge, of passive mode locking in a Tm3+, Ho3+-codoped KYWO42 laser operating in the 2000-2060 nm spectral region. An InGaAsSb-based quantum well semiconductor saturable absorber mirror is used for the initiation and stabilization of the ultrashort pulse generation. Pulses as short as 3.3 ps were generated at 2057 nm with average output powers up to 315 mW at a pulse repetition frequency of 132 MHz for 1.15 W of absorbed pump power at 802 nm from a Ti:sapphire laser

    Identification of Single Nucleotide Polymorphisms and analysis of Linkage Disequilibrium in sunflower elite inbred lines using the candidate gene approach

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    Background. Association analysis is a powerful tool to identify gene loci that may contribute to phenotypic variation. This includes the estimation of nucleotide diversity, the assessment of linkage disequilibrium structure (LD) and the evaluation of selection processes. Trait mapping by allele association requires a high-density map, which could be obtained by the addition of Single Nucleotide Polymorphisms (SNPs) and short insertion and/or deletions (indels) to SSR and AFLP genetic maps. Nucleotide diversity analysis of randomly selected candidate regions is a promising approach for the success of association analysis and fine mapping in the sunflower genome. Moreover, knowledge of the distance over which LD persists, in agronomically meaningful sunflower accessions, is important to establish the density of markers and the experimental design for association analysis. Results. A set of 28 candidate genes related to biotic and abiotic stresses were studied in 19 sunflower inbred lines. A total of 14,348 bp of sequence alignment was analyzed per individual. In average, 1 SNP was found per 69 nucleotides and 38 indels were identified in the complete data set. The mean nucleotide polymorphism was moderate ( = 0.0056), as expected for inbred materials. The number of haplotypes per region ranged from 1 to 9 (mean = 3.54 1.88). Model-based population structure analysis allowed detection of admixed individuals within the set of accessions examined. Two putative gene pools were identified (G1 and G2), with a large proportion of the inbred lines being assigned to one of them (G1). Consistent with the absence of population sub-structuring, LD for G1 decayed more rapidly (r 2= 0.48 at 643 bp; trend line, pooled data) than the LD trend line for the entire set of 19 individuals (r2= 0.64 for the same distance). Conclusion. Knowledge about the patterns of diversity and the genetic relationships between breeding materials could be an invaluable aid in crop improvement strategies. The relatively high frequency of SNPs within the elite inbred lines studied here, along with the predicted extent of LD over distances of 100 kbp (r2∼0.1) suggest that high resolution association mapping in sunflower could be achieved with marker densities lower than those usually reported in the literature.Fil:Fusari, C.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Lia, V.V. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Hopp, H.E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Heinz, R.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

    Preliminary data on the structure and potential of the Tocomar geothermal field (Puna plateau, Argentina).

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    AbstractThis study presents new stratigraphic, structural and hydrogeological data on the Tocomar geothermal volcanic area (Puna plateau, Central Andes, NW Argentina), together with preliminary geochemical and magnetotelluric data.The main geothermal reservoir is located within the fractured Pre-Palaeozoic–Ordovician units. The reservoir is recharged by meteoric waters. Geothermal fluids upwell where main regional structures intersect secondary structures associated with the development of the Tocomar basin. Preliminary data indicate a reservoir temperature of ∼ 200° C and a local geothermal gradient of ∼ 130° C/km associated with the Quaternary volcanic activity in the Tocomar area

    Long-term outcome after inflammatory abdominal aortic aneurysm repair: case-matched study

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    The purpose of this study was to compare early and late outcomes after inflammatory and noninflammatory abdominal aortic aneurysm (AAA) repair with emphasis on graft-related complications. Of 625 consecutive patients submitted to AAA repair, 18 were classified as having inflammatory AAAs (group 1). The results of this group were compared with those of 54 patients (group 2) retrospectively drawn from patients who underwent aortic replacement for noninflammatory AAAs. A computer-assisted matching system was used to match patients according to date of birth, gender, and surgical priority. All patients of both groups were followed by periodic clinical and instrumental examinations. Patients in group 1 complained more frequently of aneurysm-related symptoms (72% vs. 20%; p = 0.0001), and their erythrocyte sedimentation rate was elevated more often (78% vs. 19%; p < 0.0001). Surgical morbidity and mortality rates were not different. The mean lengths of follow-up were 61 +/- 47 months (group 1) and 71 +/- 38 months (group 2). The 10-year overall survival rates did not differ significantly between the two groups (49.1% +/- 16.9% for group 1 vs. 61.6% +/- 13.8% for group 2; p = 0.26, log-rank test). In contrast, the free from paraanastomotic aneurysm survival rates were significantly lower in group 1 (57.3% +/- 20.2% vs. 97.8% +/- 2.5% at 10 years; p = 0.025, log-rank test). Long-term outcomes showed a higher incidence of graft-related complications in group 1. As inflammatory aneurysms might represent a risk factor for the development of paraanastomotic aneurysms, routine imaging surveillance of graft aortic healing after inflammatory AAA repair is warranted

    Sensory cutaneous papillae in the sea lamprey (Petromyzonmarinus L.) : I. Neuroanatomy and physiology

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    Molecules present in an animal's environment can indicate the presence of predators,food, or sexual partners and consequently, induce migratory, reproductive, foraging,or escape behaviors. Three sensory systems, the olfactory, gustatory, and solitarychemosensory cell (SCC) systems detect chemical stimuli in vertebrates. While agreat deal of research has focused on the olfactory and gustatory system over theyears, it is only recently that significant attention has been devoted to the SCC sys-tem. The SCCs are microvillous cells that were first discovered on the skin of fish,and later in amphibians, reptiles, and mammals. Lampreys also possess SCCs that areparticularly numerous on cutaneous papillae. However, little is known regarding theirprecise distribution, innervation, and function. Here, we show that sea lampreys(Petromyzon marinus L.) have cutaneous papillae located around the oral disk, nostril,gill pores, and on the dorsal fins and that SCCs are particularly numerous on thesepapillae. Tract-tracing experiments demonstrated that the oral and nasal papillae areinnervated by the trigeminal nerve, the gill pore papillae are innervated by branchialnerves, and the dorsal fin papillae are innervated by spinal nerves. We also character-ized the response profile of gill pore papillae to some chemicals and showed thattrout-derived chemicals, amino acids, and a bile acid produced potent responses.Together with a companion study (Suntres et al., Journal of Comparative Neurology,this issue), our results provide new insights on the function and evolution of the SCCsystem in vertebrates

    Omalizumab efficacy in cases of chronic spontaneous urticaria is not explained by the inhibition of sera activity in effector cells

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    Omalizumab (OmAb) is a humanized anti-IgE antibody approved for the treatment of chronic spontaneous urticaria (CSU). OmAb's mechanism of action is known to include actions on free IgE and on pre-bound IgE. However, OmAb is equally and rapidly effective against autoimmune and non-autoimmune urticaria where IgE involvement is not clear, suggesting the involvement of additional mechanisms of action. In this study, we sought to investigate the ability of OmAb to inhibit mast cell and basophil degranulation induced by sera from CSU patients. For this purpose, we performed a comparison between the in vitro incubation of sera from CSU patients treated with OmAb and the in vivo administration of OmAb in a clinical trial. We found that OmAb added in vitro to sera from CSU patients did not modify the ability of the sera to induce cell degranulation. Similarly, the sera from patients treated with OmAb in the context of the clinical trial who had a good clinical outcome maintained the capacity to activate mast cells and basophils. Thus, we conclude that the beneficial activity of OmAb does not correlate with the ability of patient sera to induce cell degranulation
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