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41.
Spriet C Trinel D Waharte F Deslee D Vandenbunder B Barbillat J Héliot L 《Microscopy research and technique》2007,70(2):85-94
Studies of proteins' interaction in cells by FRET can take benefit from two important photo-physical properties describing fluorescent proteins: fluorescence emission spectrum and fluorescence lifetime. These properties provide specific and complementary information about the tagged proteins and their environment. However, none of them taken individually can completely quantify the involved fluorophore characteristics due to their multiparametric dependency with molecular environment, experimental conditions, and interpretation complexity. A solution to get a better understanding of the biological process implied at the cellular level is to combine the spectral and temporal fluorescence data acquired simultaneously at every cell region under investigation. We present the SLiM-SPRC160, an original temporal/spectral acquisition system for simultaneous lifetime measurements in 16 spectral channels directly attached to the descanned port of a confocal microscope with two-photon excitation. It features improved light throughput, enabling low-level excitation and minimum invasivity in living cells studies. To guarantee a fairly good level of accuracy and reproducibility in the measurements of fluorescence lifetime and spectra on living cells, we propose a rigorous protocol for running experiments with this new equipment that preserves cell viability. The usefulness of SLiM approach for the precise determination of overlapping fluorophores is illustrated with the study of known solutions of rhodamine. Then, we describe reliable FRET experiments in imaging mode realized in living cells using this protocol. We also demonstrate the benefit of localized fluorescence spectrum-lifetime acquisitions for the dynamic study of fluorescent proteins. proteins. 相似文献
42.
Maarten Houbraken Sofie Demeyer Dimitri Staessens Pieter Audenaert Didier Colle Mario Pickavet 《Natural computing》2013,12(2):277-289
Physarum polycephalum, a true slime mould, is a primitive, unicellular organism that creates networks to transport nutrients while foraging. The design of these natural networks proved to be advanced, e.g. the slime mould was able to find the shortest path through a maze. The underlying principles of this design have been mathematically modelled in literature. As in real life the slime mould can design fault tolerant networks, its principles can be applied to the design of man-made networks. In this paper, an existing model and algorithm are adapted and extended with stimulation and migration mechanisms which encourage formation of alternative paths, optimize edge positioning and allow for automated design. The extended model can then be used to better design fault tolerant networks. The extended algorithm is applied to several national and international network configurations. Results show that the extensions allow the model to capture the fault tolerance requirements more accurately. The resulting extended algorithm overcomes weaknesses in geometric graph design and can be used to design fault tolerant networks such as telecommunication networks with varying fault tolerance requirements. 相似文献
43.
Sofiane Aloui Nicolas Delaunay Eric Kerherve Nathalie Deltimple Robert Plana Didier Belot 《Analog Integrated Circuits and Signal Processing》2012,70(2):203-211
A millimeter-wave Power Amplifier (PA) based on a 65nm CMOS technology from STMicroelectronics has been designed. The targeted
feature is the unlicensed band around 60 GHz suitable for wireless personal area network application (WPAN). To optimize the
linearity, the PA is designed under class A biasing to have an output compression point (OCP1) close to its saturated Power (P
sat). S-parameters and large signal measurement results are demonstrated and compared with electromagnetic simulations. The PA
offers a P
sat of 8.3 dBm, an OCP1 of 6 dBm and a gain of 6.7 dB. The die area is 0.29 mm2 with pads. Considering those results, one-tone simulations are not sufficient to characterize the linearity performances
of the PA in its real conditions of use. Consequently, two-tone simulations are firstly performed. After, linearity figures
of merit (FoM) are discussed applying an orthogonal frequency-division multiplexing (OFDM) modulated signal. The PA offers
an adjacent channel power ratio (ACPR) of 15 dB and an error vector magnitude (EVM) of 20% at PA compression operating mode. 相似文献
44.
45.
Deborah Houssin-Agbomson Didier Jamois Christophe Proust Jérôme Daubech Sidonie Ruban Simon Jallais 《International Journal of Hydrogen Energy》2012
In order to improve risk analyses and influence the design of the future H2 systems, an experimental study on “real” leaks qualification and quantification was performed. In H2 energy applications, fittings appeared as a significant leakage potential and subsequently explosion and flame hazards. Thus, as a part of the “Horizon Hydrogène Energie” French program, four kinds of commercial fittings usually employed on H2 systems were tested thanks to a new high pressure test bench – designed, setup and operated by INERIS – allowing experiments to be led for H2 pressures until 700 bar. The fittings underwent defined stresses representative of H2 systems lifetime and beyond. The associated leaks – when existing – are characterized in terms of flow rate. 相似文献
46.
Marie Hurtgen Antoine Debuigne Didier Gigmes Christine Jérôme Christophe Detrembleur 《Polymer》2012,53(20):4353-4358
The grafting mechanism of poly(vinyl acetate) macroradicals prepared by cobalt-mediated radical polymerization onto C60 is investigated. The experimental conditions directly impact the nature and stability of the PVAc/C60 adducts. In the presence of residual initiating radicals that can compete with PVAc° macroradicals for addition onto C60, mixtures of PVAc/C60 adducts having between one and eight polymer chains per C60 are formed. PVAc/C60 adducts prepared with low [PVAc]:[C60] ratios may contain weak C60–C60 bonds that further dissociate and account for the instability of the products. The formation of such dimers can be lessened by increasing the temperature from 30 °C to 100 °C. The temperature increase also allows a complete dissociation of the PVAc-Co dormant species into PVAc° macroradicals and an almost quantitative grafting of eight PVAc chains onto C60, leading to well-defined C60(PVAc)8 octa-adducts. These results might shed new light on the grafting onto C60 of macroradicals prepared by other CRP techniques. 相似文献
47.
Egon Ostrosi Salima Tié Bi Lianda Haxhiaj Didier Klein 《The International Journal of Advanced Manufacturing Technology》2012,60(1-4):29-54
The effective modelling of configurable products must handle the complex problem of representation of the configurable products, learning new configurable products and analysis of their behaviour. However, currently in advanced CAD systems, there exists no systematic and effective method for designing configurations and integrating behavioural aspects and simulations. This paper proposes and develops a grammar-based design approach to support both the computer-aided design for configuration and computing in CAD systems. Two interrelated questions are taken into account: (1) What are the hypothesis, properties and features for product configuration? (2) How can the product based on configuration features be represented and how can the configuration representation method integrate the numerical computing in design? This approach, under the guide of the proposed formal modelling, is implemented in computers. A design case study illustrates the proposed approach. 相似文献
48.
Florian Vidal Herv Legay George Goussetis Maria Garcia Vigueras Sgolne Tubau Jean‐Didier Gayrard 《International Journal of Satellite Communications and Networking》2021,39(1):29-46
This paper proposes a methodology to benchmark satellite payload architectures and find the optimal trade‐offs between high flexibility and low complexity. High flexibility would enable the satellite to adapt to various distributions of user terminals on the ground and fulfill the data rate demand of these users. Besides, low complexity is required to keep satellite networks competitive in the context of emerging 5G networks. To estimate the flexibility of a payload, an indicator to characterize the non‐uniformity of user distributions is proposed. Each benchmarked payload may be characterized by a graph relating the throughput to this parameter further denoted . The payload provides the same throughput trends for different scenarios of user distributions with the same parameter. As a consequence, the average capacity of the system may be estimated by (a) calculating the probability distribution of over the orbit and (b) integrating the throughput based on this payload response. It thus results in a straightforward way for benchmarking payloads directly on an estimation of the averaged capacity, accounting for the user distribution over the earth. A simulation platform has been developed to characterize the payload throughput including the implementation of a resource allocation algorithm that accounts for constraints of various payloads. Using this definition and the developed tool, we benchmark a bent‐pipe architecture, a beam hopping architecture and a hybrid beam‐steering architecture for a LEO megaconstellation use case. The methodology showcases the interest for investigating different payload architectures depending on realistic traffic scenario analysis. 相似文献
49.
50.
Barbara Walther Aaron M. Lett Alessandra Bordoni Lidia Toms‐Cobos Juan Antonio Nieto Didier Dupont Francesca Danesi Danit R. Shahar Ana Echaniz Roberta Re Aida Sainz Fernandez Amlie Deglaire Doreen Gille Alexandra Schmid Guy Vergres 《Molecular nutrition & food research》2019,63(21)
Nutritional research is currently entering the field of personalized nutrition, to a large extent driven by major technological breakthroughs in analytical sciences and biocomputing. An efficient launching of the personalized approach depends on the ability of researchers to comprehensively monitor and characterize interindividual variability in the activity of the human gastrointestinal tract. This information is currently not available in such a form. This review therefore aims at identifying and discussing published data, providing evidence on interindividual variability in the processing of the major nutrients, i.e., protein, fat, carbohydrates, vitamins, and minerals, along the gastrointestinal tract, including oral processing, intestinal digestion, and absorption. Although interindividual variability is not a primary endpoint of most studies identified, a significant number of publications provides a wealth of information on this topic for each category of nutrients. This knowledge remains fragmented, however, and understanding the clinical relevance of most of the interindividual responses to food ingestion described in this review remains unclear. In that regard, this review has identified a gap and sets the base for future research addressing the issue of the interindividual variability in the response of the human organism to the ingestion of foods. 相似文献