The bacterial pathogen Xanthomonas campestris pv. vesicatoria (Xcv) uses a type III secretion system (TTSS) to translocate effector proteins into host plant cells. The TTSS is required for Xcv colonization, yet the identity of many proteins translocated through this apparatus is not known. We used a genetic screen to functionally identify Xcv TTSS effectors. A transposon 5 (Tn5)-based transposon construct including the coding sequence for the Xcv AvrBs2 effector devoid of its TTSS signal was randomly inserted into the Xcv genome. Insertion of the avrBs2 reporter gene into Xcv genes coding for proteins containing a functional TTSS signal peptide resulted in the creation of chimeric TTSS effector::AvrBs2 fusion proteins. Xcv strains containing these fusions translocated the AvrBs2 reporter in a TTSS-dependent manner into resistant BS2 pepper cells during infection, activating the avrBs2-dependent hypersensitive response (HR). We isolated seven chimeric fusion proteins and designated the identified TTSS effectors as Xanthomonas outer proteins (Xops). Translocation of each Xop was confirmed by using the calmodulin-dependent adenylate cydase reporter assay. Three xop genes are Xanthomonas spp.-specific, whereas homologs for the rest are found in other phytopathogenic bacteria. XopF1 and XopF2 define an effector gene family in Xcv. XopN contains a eukaryotic protein fold repeat and is required for full Xcv pathogenicity in pepper and tomato. The translocated effectors identified in this work expand our knowledge of the diversity of proteins that Xcv uses to manipulate its hosts.bacterial plant pathogenesis ͉ virulence proteins
Customer-oriented management of manufacturing systems is crucial in service-oriented production and product service systems. This paper develops the selection of dispatching rules in combination with alternative process flow designs and demand mix, for a maintenance, repair and overhaul center (MRO) of turbo shaft engines, both for complete engines and engine modules. After an initial systematic screening of priority dispatching rules, the design of experiments and discrete-event simulation allows a quantitative analysis of the better rules for the alternative process flows with internal and service metrics. Next, the design of experiments with analysis of variance and the Taguchi approach enables a search for the optimal combination of process flow and dispatching rules. The consideration of extra costs for overdue work orders into the costing breakdown provides a quantitative evaluation of the optimum range of load for the facility. This facilitates the discussion of the significant trade-offs of cost, service, and flexibility in the production system and the operational management alternatives for decision-making.
One of the problems that a satellite manufacturing involves is to obtain the geometrical forms and the accurate positions for the different radiofrequency components (reflectors, subreflectors and feeders). CFRP (Carbon Fibber Reinforced Plastics) sandwich structures never are obtained as designed due to the deformations associated to the manufacturing process. So, reflectors, subreflectors and structural components (towers, panels... ) have to be measured in order to include their deviations in the design of the regulation parts. High performance equipment (Co-ordinate Measurement Machines, CAD/CAM Systems and 5 Axis Machine Tool) is used, but it is also necessary to make an integrated and multidisciplinary team. This paper describes how this process was implemented in CASA Space Division during HISPASAT 1C satellite manufacturing program.
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