1,721,086 research outputs found
Effective Characterization of Relief Patterns
No full textIn this paper, we address the problem of characterizing relief patterns over surface meshes independently on the underlying shape. We propose to tackle the problem by estimating local invariant features and encoding them using the Improved Fisher Vector technique, testing both features estimated on 3D meshes and local descriptors estimated on raster images created by encoding local surface properties (e.g. mean curvature) over a surface parametrization. We compare the robustness of the obtained descriptors against noise and surface bending and evaluate retrieval performances on a specific benchmark proposed in a track of the Eurographics Shape REtrieval Contest 2017. Results show that, with the proposed framework, it is possible to obtain retrieval results largely improving the state of the art and that the image-based approach is still effective when the underlying surface is heavily deformed
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Effect of mequitamium iodide (LG 30435) on airway microvascular leakage in the guinea-pig
No full textIntravenous administration of mequitamium iodide (LG 30435) prevented the increase of tracheobronchial vascular permeability induced either by antigen challenge or by exogenous histamine in the guinea-pig, while it was ineffective against PAF, serotonin or capsaicin . These findings indicate that mequitamium iodide selectively interferes with the effect of histamine on airway microvascular leakage, mediated by histamine H1 receptors, and is more potent than diphenhydramine, mequitazine or astemizole. Histamine receptor antagonism is likely to be a major determinant of the antiallergic activity of the compound, although additional mechanisms may be involved
PAVEL: decorative patterns with packed volumetric elements
Full text linkMany real-world hand-crafted objects are decorated with elements that are packed onto the object's surface and deformed to cover it as much as possible. Examples are artisanal ceramics and metal jewelry. Inspired by these objects, we present a method to enrich surfaces with packed volumetric decorations. Our algorithm works by first determining the locations in which to add the decorative elements and then removing the non-physical overlap between them while preserving the decoration volume. For the placement, we support several strategies depending on the desired overall motif. To remove the overlap, we use an approach based on implicit deformable models creating the qualitative effect of plastic warping while avoiding expensive and hard-to-control physical simulations. Our decorative elements can be used to enhance virtual surfaces, as well as 3D-printed pieces, by assembling the decorations onto real surfaces to obtain tangible reproductions
Prostaglandin E(2) primes the angiogenic switch via a synergic interaction with the fibroblast growth factor-2 pathway
No full textRATIONALE:
Prostaglandin (PG)E(2) exerts temporally distinct actions on blood vessels, immediate vasodilatation, and long-term activation of angiogenesis.
OBJECTIVE:
To study the mechanism of PGE(2) induction of angiogenesis, we characterized its effect on fibroblast growth factor (FGF)-2 signaling in cultured endothelial cells and in ex vivo and in vivo assays of blood vessel formation.
METHODS AND RESULTS:
Using Western blotting assay, we demonstrated that PGE(2) induced upregulation of components of the FGF-2 pathway: FGF-2 protein, phosphorylation of FGF receptor type 1 (FGFR1), activation of FRS2alpha (FGFR substrate 2alpha), phospholipase Cgamma, endothelial nitric oxide synthase, extracellular signal-regulated kinase 1/2, and the transcription factor STAT-3. Synergism between PGE(2) and FGF-2 promoted endothelial cell proliferation and robust angiogenesis in vivo, in rabbit cornea and Matrigel assays. The magnitude of the angiogenic response to PGE(2) was directly related to FGF-2 availability which determined the extent of FGFR1 activation. In fact, PGE(2) induction of angiogenesis in vitro was impaired in FGF-2(-/-) endothelial cells and FGFR1 blockade abrogated PGE(2) action on the endothelium, preventing the activation of FGF-2 signaling.
CONCLUSION:
We propose a model for the angiogenic switch based on the autocrine/paracrine FGF-2/FGFR1 activation by PGE(2) and FGF-2 synergistic interaction. The synergism between the PGE(2) and FGF-2 signaling pathways here described may explain the mechanism of action of drug combinations, the most notable being cyclooxygenase inhibitors with growth factors or growth factor receptor inhibitors
Reliability of three-dimensional photonic scanner anthropometry performed by skilled and naïve operators
No full textThis work explored the relative and absolute reliability of three-dimensional (3D) anthropometry performed by skilled and naïve operators using a fast, pose tolerant whole-body 3D scanner device. Upon skin landmarking by an experienced operator (skilled anthropometrist, SA), twelve subjects (six males and six females) underwent a thorough 3D anthropometric evaluation by the SA and two naïve operators (NA). Using the same landmarks, the SA also performed traditional anthropometry measurements. All measurements were taken twice. Relative reliability was tested with the Pearson's correlation coefficient r and the intraclass correlation coefficient (ICC); absolute reliability was tested calculating the percentage coefficient of variation (%CV), the standard error of measurement (SEM), the percentage technical error of measurement (%TEM), and paired Student's t test. Results showed that intra-operator relative and absolute reliability was excellent for all and most 3D measurement items, respectively, independently of the operator's skill. Inter-operator (SA vs. individual NA) relative reliability was excellent as well; inter-operator absolute reliability was not acceptable for about only 30% of measurement items. Results of this work show that 3D anthropometry has strong potential in anthropometry due to high intrinsic reliability and less need for operator training vs. traditional anthropometry
Different mechanism of tachykinin NK2 receptor blockade by SR 48968 and MEN 10,627 in the guinea-pig isolated gallbladder and colon
No full textThe mechanism of action of the tachykinin NK2 receptor antagonists, SR 48968 ((S)-N-methyl-N[4-acetylamino-4-phenyl-piperidino)-2-(3,4- dichlorophenyl)butyl]benzmide) and MEN 10,627 (cyclo[Met-Asp-Trp-Phe-Dap-Leu) cyclo (2β-5β)]), was compared in the guinea-pig isolated gallbladder and circular muscle of proximal colon by using neurokinin A and [βAla8]neurokinin A-(4-10) as agonists. The experiments performed with colon were in the presence of the tachykinin NK1 receptor-selective antagonist, (±)-CP-96345 (([2-(diphenylmethyl)-N-[(2-methoxyphenyl]-methyl]-11-azabicyclo[2,2,2]octan-3-amine]) SR 48968 caused an insurmountable antagonism of tachykinin NK2 receptor-mediated contraction in both preparations; its blockade was essentially irreversible, since it was not reversed by washout (up to 2 h) and was increased by prolonging the incubation from 15 to 120 min. In contrast, MEN 10,627 produced simple competitive antagonism, which was time-independent and fully reversible in both preparations. In both preparations, the simultaneous administration of SR 48968 and MEN 10,627 produced an intermediate antagonism of the responses to the agonists, as compared to the antagonism produced by each antagonist alone. The present results are discussed in the light of the reported interaction of SR 48968 with tachykinin NK2 receptors at a recognition epitope distinct from that of agonist(s
Facilitation of reflex micturition by intravesical administration of [βAla8]-neurokinin A (4-10), a selective NK-2 tachykinin receptor agonist
No full textThe ability of a selective agonist for NK-2 tackhykinin receptors to stimulate micturition in anaesthetised rats and guinea-pigs was investigated.
In both species, the intravesical instillation of the peptide at uM concentrations reduced bladder capacity and residual volume, indicating a facilitatory effect on reflex micturition, whereas no plasma extravasation was produced as determined by Evans Blue leakage.
In experiments on the isolated rat or guinea-pig bladder strips, the peptide induced powerful contractions. In a in vitro model of the guinea-pig whole bladder the intravesical instillation of the agonist facilitated the occurrence of rhythmic contractile activity.
The selective NK-2 receptor agonist is likely able to cross the urothelium and stimulate smooth muscle contraction
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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