4 research outputs found

    Remote Sensing Applications for Abating Aircraft–Bird Strike Risks in Southeast Brazil

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    The rising number of aircraft collisions with birds requires the development of appropriate mitigation measures to control their populations in the vicinity of airports. The black vulture (Coragyps atratus; vultures) is considered one of the most dangerous species for aviation in Brazil. To better understand the spatial distribution patterns of flying vultures and the risks they may pose to aviation, we studied natural and anthropogenic superficial factors and then numerically estimated and mapped the risk of collision with birds over the Airport Safety Area (ASA) for the Amarais Airport and Presidente Prudente Airport in the southeast part of Brazil. To conduct our research, we surveyed soaring black vultures monthly between September 2012 and August 2013 from 26 points within 20-km ASA zones. We obtained the environmental parameters (i.e., relief, surface temperature, surface covering type, and anthropogenic pressure) from satellite imagery and georeferenced them with our vulture survey. The tabulated data were examined using Spearman’s rank correlation and principal component analysis to determine if any the relationships existed between vulture flight patterns and ASA environmental characteristics. We found that the contrast in surface temperatures correlated well with the intensity of vulture soaring flights. Vultures tend to soar using the strongest thermals in their surroundings. Relief parameters, including altitude above sea level, slope exposure, and inclination, were not related with the vulture soaring activity. Water bodies and roadways were the most attractive landscapes for soaring vultures. We recorded the least number of soaring vultures over the uninterrupted urbanized lands. However, the scattered enclaves of urban settlement surrounded by natural and rural landscapes were selected by soaring birds. To mitigate the bird strike risk in ASA zones, we propose that managers should plot the objects generating thermals that attract vultures on risk assessment maps and reroute aviation to avoid them

    Discovery of Leptospira spp. seroreactive peptides using ORFeome phage display.

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    BACKGROUND:Leptospirosis is the most common zoonotic disease worldwide. The diagnostic performance of a serological test for human leptospirosis is mainly influenced by the antigen used in the test assay. An ideal serological test should cover all serovars of pathogenic leptospires with high sensitivity and specificity and use reagents that are relatively inexpensive to produce and can be used in tropical climates. Peptide-based tests fulfil at least the latter two requirements, and ORFeome phage display has been successfully used to identify immunogenic peptides from other pathogens. METHODOLOGY/PRINCIPAL FINDINGS:Two ORFeome phage display libraries of the entire Leptospira spp. genomes from five local strains isolated in Malaysia and seven WHO reference strains were constructed. Subsequently, 18 unique Leptospira peptides were identified in a screen using a pool of sera from patients with acute leptospirosis. Five of these were validated by titration ELISA using different pools of patient or control sera. The diagnostic performance of these five peptides was then assessed against 16 individual sera from patients with acute leptospirosis and 16 healthy donors and was compared to that of two recombinant reference proteins from L. interrogans. This analysis revealed two peptides (SIR16-D1 and SIR16-H1) from the local isolates with good accuracy for the detection of acute leptospirosis (area under the ROC curve: 0.86 and 0.78, respectively; sensitivity: 0.88 and 0.94; specificity: 0.81 and 0.69), which was close to that of the reference proteins LipL32 and Loa22 (area under the ROC curve: 0.91 and 0.80; sensitivity: 0.94 and 0.81; specificity: 0.75 and 0.75). CONCLUSIONS/SIGNIFICANCE:This analysis lends further support for using ORFeome phage display to identify pathogen-associated immunogenic peptides, and it suggests that this technique holds promise for the development of peptide-based diagnostics for leptospirosis and, possibly, of vaccines against this pathogen

    The Cytoplasmic Hsp70 Chaperone Machinery Subjects Misfolded and Endoplasmic Reticulum Import-incompetent Proteins to Degradation via the Ubiquitin–Proteasome System

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    The mechanism of protein quality control and elimination of misfolded proteins in the cytoplasm is poorly understood. We studied the involvement of cytoplasmic factors required for degradation of two endoplasmic reticulum (ER)-import–defective mutated derivatives of carboxypeptidase yscY (ΔssCPY* and ΔssCPY*-GFP) and also examined the requirements for degradation of the corresponding wild-type enzyme made ER-import incompetent by removal of its signal sequence (ΔssCPY). All these protein species are rapidly degraded via the ubiquitin–proteasome system. Degradation requires the ubiquitin-conjugating enzymes Ubc4p and Ubc5p, the cytoplasmic Hsp70 Ssa chaperone machinery, and the Hsp70 cochaperone Ydj1p. Neither the Hsp90 chaperones nor Hsp104 or the small heat-shock proteins Hsp26 and Hsp42 are involved in the degradation process. Elimination of a GFP fusion (GFP-cODC), containing the C-terminal 37 amino acids of ornithine decarboxylase (cODC) directing this enzyme to the proteasome, is independent of Ssa1p function. Fusion of ΔssCPY* to GFP-cODC to form ΔssCPY*-GFP-cODC reimposes a dependency on the Ssa1p chaperone for degradation. Evidently, the misfolded protein domain dictates the route of protein elimination. These data and our further results give evidence that the Ssa1p-Ydj1p machinery recognizes misfolded protein domains, keeps misfolded proteins soluble, solubilizes precipitated protein material, and escorts and delivers misfolded proteins in the ubiquitinated state to the proteasome for degradation
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