587 research outputs found
IdeaValuation : Favoriser les échanges lors d'un atelier de créativité par le vote qualitatif des idées à l'aide d'un outil numérique
International audienceIn the context of the emergence of collaborative innovation projects, the animation of creative sessions permits to identify new opportunities. The number of ideas generated is a lot more important than the number of collaborative projects implemented. To improve this ratio, we assume that group discussions could be facilitated by the cleavage of opinions about the quality of the ideas discussed during the meeting. We support our approach with a digital tool to promote information feedback throughout the session.Dans le cadre de l'émergence de projets collaboratifs d'innovation, l'animation de séance de créativité permet d'identifier de nouvelles opportunités. Généralement, le nombre d'idées générées est bien plus important que le nombre de suites données (e.g. étude, lancement et montage de projets associés). Afin d'améliorer ce ratio, nous faisons les hypothèses que d'une part les évaluations et discussions en groupe sur les idées proposées pourraient être facilitées, et d'autre part que la singularité d'opinions concernant la qualité des idées évoquées en séance peut être facilitateur d'échanges. Pour cela, nous appuyons notre démarche par un outil numérique pour réaliser le partage d'informations des évaluations tout au long de la séance de créativité
Improved mass spectrometry compatibility is afforded by ammoniacal silver staining
Sequence coverage in MS analysis of protein digestion-derived peptides is a
key issue for detailed characterization of proteins or identification at low
quantities. In gel-based proteomics studies, the sequence coverage greatly
depends on the protein detection method. It is shown here that ammoniacal
silver detection methods offer improved sequence coverage over standard silver
nitrate methods, while keeping the high sensitivity of silver staining. With
the development of 2D-PAGE-based proteomics, another burden is placed on the
detection methods used for protein detection on 2-D-gels. Besides the classical
requirements of linearity, sensitivity, and homogeneity from one protein to
another, detection methods must now take into account another aspect, namely
their compatibility with MS. This compatibility is evidenced by two different
and complementary aspects, which are (i) the absence of adducts and artefactual
modifications on the peptides obtained after protease digestion of a protein
detected and digested in - gel, and (ii) the quantitative yield of peptides
recovered after digestion and analyzed by the mass spectrometer. While this
quantitative yield is not very important per se, it is however a crucial
parameter as it strongly influences the S/N of the mass spectrum and thus the
number of peptides that can be detected from a given protein input, especially
at low protein amounts. This influences in turn the sequence coverage and thus
the detail of the analysis provided by the mass spectrometer.Comment: website publisher http://www.interscience.wiley.co
Mitochondrial proteomics: analysis of a whole mitochondrial extract with two-dimensional electrophoresis
Mitochondria are complex organelles, and their proteomics analysis requires a
combination of techniques. The emphasis in this chapter is made first on
mitochondria preparation from cultured mammalian cells, then on the separation
of the mitochondrial proteins with two-dimensional electrophoresis (2DE),
showing some adjustment over the classical techniques to improve resolution of
the mitochondrial proteins. This covers both the protein solubilization, the
electrophoretic part per se, and the protein detection on the gels, which makes
the interface with the protein identification part relying on mass
spectrometry
Alterations of the mitochondrial proteome caused by the absence of mitochondrial DNA: A proteomic view
The proper functioning of mitochondria requires that both the mitochondrial
and the nuclear genome are functional. To investigate the importance of the
mitochondrial genome, which encodes only 13 subunits of the respiratory
complexes, the mitochondrial rRNAs and a few tRNAs, we performed a comparative
study on the 143B cell line and on its Rho-0 counterpart, i.e., devoid of
mitochondrial DNA. Quantitative differences were found, of course in the
respiratory complexes subunits, but also in the mitochondrial translation
apparatus, mainly mitochondrial ribosomal proteins, and in the ion and protein
import system, i.e., including membrane proteins. Various mitochondrial
metabolic processes were also altered, especially electron transfer proteins
and some dehydrogenases, but quite often on a few proteins for each pathway.
This study also showed variations in some hypothetical or poorly characterized
proteins, suggesting a mitochondrial localization for these proteins. Examples
include a stomatin-like protein and a protein sharing homologies with bacterial
proteins implicated in tyrosine catabolism. Proteins involved in apoptosis
control are also found modulated in Rho-0 mitochondria.Comment: website publisher: http://www3.interscience.wiley.com
Sweet silver: A formaldehyde-free silver staining using aldoses as developing agents, with enhanced compatibility with mass spectrometry
Protein detection methods after electrophoresis have to be sensitive,
homogeneous, and not to impair downstream analysis of proteins by MS. Speed,
low cost, and user friendliness are also favored features. Silver staining
combines many of these features, but its compatibility with MS is limited. We
describe here, a new variant of silver staining that is completely
formaldehyde-free. Reducing sugars in alkaline borate buffer are used as
developers. While keeping the benefits of silver staining, this method is shown
to afford a much better performance in terms of compatibility with MS, both in
PMF by MALDI and in LC/ESI/MS/MS
About thiol derivatization and resolution of basic proteins in two-dimensional electrophoresis.
web publisher www.interscience.wiley.comInternational audienceThe influence of thiol blocking on the resolution of basic proteins by two-dimensional electrophoresis was investigated. Cysteine blocking greatly increased resolution and decreased streaking, especially in the basic region of the gels. Two strategies for cysteine blocking were found to be efficient: classical alkylation with maleimide derivatives and mixed disulfide exchange with an excess of a low molecular weight disulfide. The effect on resolution was significant enough to allow correct resolution of basic proteins with in-gel rehydration on wide gradients (e.g. 3-10 and 4-12), but anodic cup-loading was still required for basic gradients (e.g. 6-12 or 8-12). These results demonstrate that thiol-related problems are not solely responsible for streaking of basic proteins on two-dimensional gels
Rapid onset of collectivity in the vicinity of 78Ni
gamma-rays following the B and B-n decay of the very neutron rich 84Ga
produced by photo-fission of 238U have been studied at the newly built ISOL
facility of IPN Orsay: ALTO. Two activities were observed and assigned to two
B-decaying states: 84gGa, I = (0\^-) and 84mGa, I = (3\^-, 4\^-). Excitation
energies of the 2+1 and 4+1 excited states of 84Ge were measured at E(2+1) =
624.3 keV and E(4+1) = 1670.1 keV. Comparison with HFB+GCM calculations allows
to establish the collective character of this nucleus indicating a substantial
N=50 core polarization. The excitation energy of the 1/2+1 state in 83Ga known
to carry a large part of the neutron 3s1/2 strength was measured at 247.8keV.
Altogether these data allow to confirm the new single particle state ordering
which appears immediately after the double Z=28 and N=50 shell closure and to
designate 78Ni as a fragile and easily polarized doubly-magic core.Comment: 4 pages, ReVTe
Multi-parameter monitoring of a solution mining cavity collapse : first insight of precursors
International audienceIn order to improve our understanding of the large-scale ground failure phenomena caused by old underground mining works, a solution mine was instrumented in 2004 prior to its collapse as part of the mining scheme. A permanent monitoring system was set up, including a high-resolution microseismic network linked to a surface field-displacement measurement system. The large amount of data transmitted for on-line processing provided daily insight into the evolution of the geological system. First, microseismic activity showed upward progressive failure migration throughout 2008 without any significant surface movement. Second, after two days of intensive brine extraction, a high microseismicity and energy release rate marked the failure of a thin and very rigid bed at a depth of 120 m. This failure occurred 24 hours before the final collapse; it was followed by transient brine pressure signals, and by acceleration of the surface subsidence rate, reaching 1 milt in the final phas
- …
