745 research outputs found

    RAFCON: a Graphical Tool for Task Programming and Mission Control

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    There are many application fields for robotic systems including service robotics, search and rescue missions, industry and space robotics. As the scenarios in these areas grow more and more complex, there is a high demand for powerful tools to efficiently program heterogeneous robotic systems. Therefore, we created RAFCON, a graphical tool to develop robotic tasks and to be used for mission control by remotely monitoring the execution of the tasks. To define the tasks, we use state machines which support hierarchies and concurrency. Together with a library concept, even complex scenarios can be handled gracefully. RAFCON supports sophisticated debugging functionality and tightly integrates error handling and recovery mechanisms. A GUI with a powerful state machine editor makes intuitive, visual programming and fast prototyping possible. We demonstrated the capabilities of our tool in the SpaceBotCamp national robotic competition, in which our mobile robot solved all exploration and assembly challenges fully autonomously. It is therefore also a promising tool for various RoboCup leagues.Comment: 8 pages, 5 figure

    Cardiac transplantation: five years' activity

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    OBJECTIVE: To analyze the initial five years experience of the new heart transplant program of Coimbra University Hospitals. METHODS: Between November 2003 aid December 2008, 132 patients were transplanted, with a mean age of 52.0 years (range 3-71 years), of whom 98 were male (74%). Half of the patients had dilated cardiomyopathy and 33% ischemic cardiomyopathy. The mean age of donors was 31.7 years and 102 were male (77%). Donor hearts were harvested at a distance in 62% of cases. There was a gender mismatch between donor and recipient (F:M) in 19% of cases and ABO blood type disparity (not identical but compatible) in 11%. In all cases we used the technique of total transplantation with bicaval anastomosis, modified in this center. Mean ischemia time was 88.9 +/- 32.2 minutes. All patients received induction therapy with basiliximab and methylprednisolone. RESULTS: Six patients (4.5%) died within 30 days or during hospitalization, due to graft failure in four and hyperacute rejection in two. Two patients required prolonged ventilation, ten (8%) required inotropic support for more than 48 hours, and four required pacemaker implantation. Mean hospital stay was 15.6 +/- 15.2 days (median 13 days). Ninety percent of patients (116/129) were maintained on triple immunosuppressive therapy, including cyclosporine, the remainder receiving tacrolimus. In 23 patients it was necessary to change the immunosuppressive regimen due to renal and/or tumoral complications, or humoral rejection. All patients are followed regularly in the Surgical Center. Thirteen patients (10%) died late of cancer (6 patients), infection (4 patients), and pancreatitis, pulmonary hypertension and suicide (one patient each). Twenty-two patients (17%) had 25 episodes of cellular rejection (> or = 2R), with clinical consequences in only one case, and five had humoral rejection (3.9%). No patients died of late rejection, but there is evidence of mild graft vascular disease in one. Actuarial survival (Kaplan-Meier) at one and five years was 90% and 82%, respectively. CONCLUSION: In this initial series of five years we obtained results equivalent to or bette than those in centers with wider and longer experience, aided by self-correction arising from our own experience. This program has increased the rate of cardiac transplantation in Portugal to above the European average

    Biliary Bicarbonate Secretion Constitutes a Protective Mechanism against Bile Acid-Induced Injury in Man

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    Background: Cholangiocytes expose a striking resistance against bile acids: while other cell types, such as hepatocytes, are susceptible to bile acid-induced toxicity and apoptosis already at micromolar concentrations, cholangiocytes are continuously exposed to millimolar concentrations as present in bile. We present a hypothesis suggesting that biliary secretion of HCO(3)(-) in man serves to protect cholangiocytes against bile acid-induced damage by fostering the deprotonation of apolar bile acids to more polar bile salts. Here, we tested if bile acid-induced toxicity is pH-dependent and if anion exchanger 2 (AE2) protects against bile acid-induced damage. Methods: A human cholangiocyte cell line was exposed to chenodeoxycholate (CDC), or its glycine conjugate, from 0.5 mM to 2.0 mM at pH 7.4, 7.1, 6.7 or 6.4, or after knockdown of AE2. Cell viability and apoptosis were determined by WST and caspase-3/-7 assays, respectively. Results: Glycochenodeoxycholate (GCDC) uptake in cholangiocytes is pH-dependent. Furthermore, CDC and GCDC (pK(a) 4-5) induce cholangiocyte toxicity in a pH-dependent manner: 0.5 mM CDC and 1 mM GCDC at pH 7.4 had no effect on cell viability, but at pH 6.4 decreased viability by >80% and increased caspase activity almost 10- and 30-fold, respectively. Acidification alone had no effect. AE2 knockdown led to 3- and 2-fold enhanced apoptosis induced by 0.75 mM CDC or 2 mM GCDC at pH 7.4. Discussion: These data support our hypothesis of a biliary HCO(3)(-) umbrella serving to protect human cholangiocytes against bile acid-induced injury. AE2 is a key contributor to this protective mechanism. The development and progression of cholangiopathies, such as primary biliary cirrhosis, may be a consequence of genetic and acquired functional defects of genes involved in maintaining the biliary HCO(3)(-) umbrella. Copyright (C) 2011 S. Karger AG, Base

    NRPSsp: non-ribosomal peptide synthase substrate predictor

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    ABSTRACT Summary: Non-Ribosomal Peptide Synthetases (NRPSs) are multimodular enzymes which biosynthesize many important peptide compounds produced by bacteria and fungi. Some studies have revealed that an individual domain within the NRPSs shows significant substrate selectivity. The discovery and characterisation of nonribosomal peptides are of great interest for the biotechnological industries. We have applied computational mining methods in order to build a database of NRPSs modules which bind to specific substrates. We have used this database to build an HMM predictor of substrates which bind to a given NRPS. Availability: The database and the predictor are freely available on an easy-to-use website at www.nrpssp.com

    ASASSN-14ae: a tidal disruption event at 200 Mpc

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    ASASSN-14ae is a candidate tidal disruption event (TDE) found at the centre of SDSS J110840.11+340552.2 (d ≃ 200 Mpc) by the All-Sky Automated Survey for Supernovae (ASAS-SN). We present ground-based and Swift follow-up photometric and spectroscopic observations of the source, finding that the transient had a peak luminosity of L ≃ 8 × 1043 erg s−1 and a total integrated energy of E ≃ 1.7 × 1050 erg radiated over the ∼5 months of observations presented. The blackbody temperature of the transient remains roughly constant at T ∼ 20 000 K while the luminosity declines by nearly 1.5 orders of magnitude during this time, a drop that is most consistent with an exponential, L ∝ e-t/t 0 with t0 ≃ 39 d. The source has broad Balmer lines in emission at all epochs as well as a broad He ii feature emerging in later epochs. We compare the colour and spectral evolution to both supernovae and normal AGN to show that ASASSN-14ae does not resemble either type of object and conclude that a TDE is the most likely explanation for our observations. At z = 0.0436, ASASSN-14ae is the lowest-redshift TDE candidate discovered at optical/UV wavelengths to date, and we estimate that ASAS-SN may discover 0.1–3 of these events every year in the future

    Effect of allergen-specific immunotherapy with purified Alt a1 on AMP responsiveness, exhaled nitric oxide and exhaled breath condensate pH: a randomized double blind study

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    <p>Abstract</p> <p>Background</p> <p>Little information is available on the effect of allergen-specific immunotherapy on airway responsiveness and markers in exhaled air. The aims of this study were to assess the safety of immunotherapy with purified natural Alt a1 and its effect on airway responsiveness to direct and indirect bronchoconstrictor agents and markers in exhaled air.</p> <p>Methods</p> <p>This was a randomized double-blind trial. Subjects with allergic rhinitis with or without mild/moderate asthma sensitized to <it>A alternata </it>and who also had a positive skin prick test to Alt a1 were randomized to treatment with placebo (n = 18) or purified natural Alt a1 (n = 22) subcutaneously for 12 months. Bronchial responsiveness to adenosine 5'-monophosphate (AMP) and methacholine, exhaled nitric oxide (ENO), exhaled breath condensate (EBC) pH, and serum Alt a1-specific IgG<sub>4 </sub>antibodies were measured at baseline and after 6 and 12 months of treatment. Local and systemic adverse events were also registered.</p> <p>Results</p> <p>The mean (95% CI) allergen-specific IgG<sub>4 </sub>value for the active treatment group increased from 0.07 μg/mL (0.03-0.11) at baseline to 1.21 μg/mL (0.69-1.73, P < 0.001) at 6 months and to 1.62 μg/mL (1.02-2.22, P < 0.001) at 12 months of treatment. In the placebo group, IgG<sub>4 </sub>value increased nonsignificantly from 0.09 μg/mL (0.06-0.12) at baseline to 0.13 μg/mL (0.07-0.18) at 6 months and to 0.11 μg/mL (0.07-0.15) at 12 months of treatment. Changes in the active treatment group were significantly higher than in the placebo group both at 6 months (P < 0.001) and at 12 months of treatment (P < 0.0001). However, changes in AMP and methacholine responsiveness, ENO and EBC pH levels were not significantly different between treatment groups. The overall incidence of adverse events was comparable between the treatment groups.</p> <p>Conclusion</p> <p>Although allergen-specific immunotherapy with purified natural Alt a1 is well tolerated and induces an allergen-specific IgG<sub>4 </sub>response, treatment is not associated with changes in AMP or methacholine responsiveness or with significant improvements in markers of inflammation in exhaled air. These findings suggest dissociation between the immunotherapy-induced increase in IgG<sub>4 </sub>levels and its effect on airway responsiveness and inflammation.</p

    Discretization of the Region of Interest

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    [EN]The meccano method was recently introduced to construct simultaneously tetrahedral meshes and volumetric parameterizations of solids. The method requires the information of the solid geometry that is defined by its surface, a meccano, i.e., an outline of the solid defined by connected polyhedral pieces, and a tolerance that fixes the desired approximation of the solid surface. The method builds an adaptive tetrahedral mesh of the solid (physical domain) as a deformation of an appropriate tetrahedral mesh of the meccano (parametric domain). The main stages of the procedure involve an admissible mapping between the meccano and the solid boundaries, the nested Kossaczký’s refinement, and our simultaneous untangling and smoothing algorithm. In this chapter, we focus on the application of the method to build tetrahedral meshes over complex terrain, that is interesting for simulation of environmental processes. A digital elevation map of the terrain, the height of the domain, and the required orography approximation are given as input data. In addition, the geometry of buildings or stacks can be considered. In these applications, we have considered a simple cuboid as meccano.Ministerio de Economía y Competitividad, Gobierno de España; Fondos FEDER; Departamento de Educación, Junta de Castilla y León; CONACYT-SENER, Fondo Sectorial CONACYT SENER HIDROCARBUROS

    Tensor voting for robust color edge detection

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    The final publication is available at Springer via http://dx.doi.org/10.1007/978-94-007-7584-8_9This chapter proposes two robust color edge detection methods based on tensor voting. The first method is a direct adaptation of the classical tensor voting to color images where tensors are initialized with either the gradient or the local color structure tensor. The second method is based on an extension of tensor voting in which the encoding and voting processes are specifically tailored to robust edge detection in color images. In this case, three tensors are used to encode local CIELAB color channels and edginess, while the voting process propagates both color and edginess by applying perception-based rules. Unlike the classical tensor voting, the second method considers the context in the voting process. Recall, discriminability, precision, false alarm rejection and robustness measurements with respect to three different ground-truths have been used to compare the proposed methods with the state-of-the-art. Experimental results show that the proposed methods are competitive, especially in robustness. Moreover, these experiments evidence the difficulty of proposing an edge detector with a perfect performance with respect to all features and fields of application.This research has been supported by the Swedish Research Council under the project VR 2012-3512

    What Does It Drive the Relationship Between Suicides and Economic Conditions? New Evidence from Spain

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    In this paper we analyse suicides across the 17 Spanish regions over the period 2002?2013. In doing so, we estimate count panel data models considering gender differences taking into account before and during economic crisis periods. A range of aggregate socioeconomic regional-level factors have been considered. Our empirical results show that: (1) a socioeconomic urban?rural suicide differentials exist, (2) there exists a Mediterranean suicide pattern; and (3) unemployment levels have a marked importance during the crisis period. The results of this study may have usefulness for suicide prevention in Spain
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