Inversion-based control of electromechanical systems using causal graphical descriptions

Causal Ordering Graph and Energetic Macroscopic Representation are graphical descriptions to model electromechanical systems using integral causality. Inversion rules have been defined in order to deduce control structure step-bystep from these graphical descriptions. These two modeling tools can be used together to develop a two-layer control of system with complex parts. A double-drive paper system is taken as an example. The deduced control yields good performances of tension regulation and velocity tracking

Inversion-based control of electromechanical systems using causal graphical descriptions

Causal Ordering Graph and Energetic Macroscopic Representation are graphical descriptions to model electromechanical systems using integral causality. Inversion rules have been defined in order to deduce control structure step-bystep from these graphical descriptions. These two modeling tools can be used together to develop a two-layer control of system with complex parts. A double-drive paper system is taken as an example. The deduced control yields good performances of tension regulation and velocity tracking

Inversion-based control of electromechanical systems using causal graphical descriptions

Causal Ordering Graph and Energetic Macroscopic Representation are graphical descriptions to model electromechanical systems using integral causality. Inversion rules have been defined in order to deduce control structure step-bystep from these graphical descriptions. These two modeling tools can be used together to develop a two-layer control of system with complex parts. A double-drive paper system is taken as an example. The deduced control yields good performances of tension regulation and velocity tracking

The Flavobacterium psychrophilum OmpA, an outer membrane glycoprotein, induces a humoral response in rainbow trout

International audienceAims: The purpose of this study was to characterize OmpA, a major glycoprotein isolated from the membrane fraction of Flavobacterium psychrophilum, and to evaluate its potential as antigenic unit in a possible vaccine. Methods and Results: The expression product of ompA is a 465-amino-acid protein precursor that contains a 21-amino acid signal peptide and has overall homology (up to 60% identity) with similarly sized proteins of some bacteria belonging to the Flavobacteriaceae family. The carboxy-terminal region contains the ‘OmpA ⁄ MotB’ domain ⁄ signature and five putative ‘Thrombospondin type 3 repeats’ domains have been identified in the central region. OmpA was clearly detected in the outer membrane fraction and its surface exposure was demonstrated. OmpA is one of the immunodominant antigens and binding of specific anti-OmpA antibodies lead to cell lysis in the presence of complement. Fish immunized with OmpA emulsified with Freund’s adjuvant developed a high antibody titter. Conclusions: Collectively, the data obtained here indicate that OmpA may be involved in Fl. psychrophilum ⁄ host cell interactions and appears to be a potential immunogen for a vaccine. Significance and Impact of the Study: This study is one step in the direction of understanding pathogenesis of Fl. psychrophilum and development of future vaccine

Protein Phase Behavior in Aqueous Solutions: Crystallization, Liquid-Liquid Phase Separation, Gels, and Aggregates

The aggregates and gels commonly observed during protein crystallization have generally been considered disordered phases without further characterization. Here their physical nature is addressed by investigating protein salting-out in ammonium sulfate and sodium chloride for six proteins (ovalbumin, ribonuclease A, soybean trypsin inhibitor, lysozyme, and β-lactoglobulin A and B) at 4°C, 23°C, and 37°C. When interpreted within the framework of a theoretical phase diagram obtained for colloidal particles displaying short-range attractive interactions, the results show that the formation of aggregates can be interpreted theoretically in terms of a gas-liquid phase separation for aggregates that are amorphous or gel-like. A notable additional feature is the existence of a second aggregation line observed for both ovalbumin and ribonuclease A in ammonium sulfate, interpreted theoretically as the spinodal. Further investigation of ovalbumin and lysozyme reveals that the formation of aggregates can be interpreted, in light of theoretical results from mode-coupling theory, as a kinetically trapped state or a gel phase that occurs through the intermediate of a gas-liquid phase separation. Despite the limitations of simple theoretical models of short-range attractive interactions, such as their inability to reproduce the effect of temperature, they provide a framework useful to describe the main features of protein phase behavior

Inversion-based control of electromechanical systems using causal graphical descriptions

Causal Ordering Graph and Energetic Macroscopic Representation are graphical descriptions to model electromechanical systems using integral causality. Inversion ruleshave been defined in order to deduce control structure step-bystep from these graphical descriptions. These two modeling tools can be used together to develop a two-layer control of system with complex parts. A double-drive paper system is taken as an example. The deduced control yields good performances of tension regulation and velocity tracking

A Protective Immune Response Is Generated in Rainbow Trout by an OmpH-Like Surface Antigen (P18) of Flavobacterium psychrophilum

Investigations of the surface characteristics of Flavobacterium psychrophilum, an important pathogen of fish, assisted us in identifying a surface protein termed P18. In the current study, we developed a simple and efficient procedure for the purification of this protein by a two-step method. First, P18 was selectively released from flavobacteria by a heat-HEPES treatment of the cells and then subjected to anion-exchange high-performance liquid chromatography. De novo sequencing was used to generate a fragmented peptide spectrum from purified P18. Comparison of two obtained peptide sequences with a partial genome sequence of F. psychrophilum (INRA, Jouy-en-Josas, France) identified one gene encoding a 166-amino-acid OmpH-like protein that mostly likely undergoes N-terminal cleavage of the 23-residue signal peptide. The susceptibility of the OmpH-like protein to proteinase K treatment and the bacteriostatic/bactericidal activities of anti-OmpH-like protein antibodies indicated that this protein is actually exposed on the surface of F. psychrophilum. Vaccination trials showed that the OmpH-like protein can induce a high titer of anti-OmpH-like protein antibodies which are protective. Taken together, these results suggest that this surface protein produced by F. psychrophilum could be used in future vaccine development as a promising candidate antigen

In vivo characterization of two additional Leishmania donovani strains using the murine and hamster model

Leishmania donovani is a protozoan parasite causing the neglected tropical disease visceral leishmaniasis. One difficulty to study the immunopathology upon L. donovani infection is the limited adaptability of the strains to experimental mammalian hosts. Our knowledge about L. donovani infections relies on a restricted number of East African strains (LV9, 1S). Isolated from patients in the 1960s, these strains were described extensively in mice and Syrian hamsters and have consequently become 'reference' laboratory strains. L. donovani strains from the Indian continent display distinct clinical features compared to East African strains. Some reports describing the in vivo immunopathology of strains from the Indian continent exist. This study comprises a comprehensive immunopathological characterization upon infection with two additional strains, the Ethiopian L. donovani L82 strain and the Nepalese L. donovani BPK282 strain in both Syrian hamsters and C57BL/6 mice. Parameters that include parasitaemia levels, weight loss, hepatosplenomegaly and alterations in cellular composition of the spleen and liver, showed that the L82 strain generated an overall more virulent infection compared to the BPK282 strain. Altogether, both L. donovani strains are suitable and interesting for subsequent invivo investigation of visceral leishmaniasis in the Syrian hamster and the C57BL/6 mouse model