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61.
Yanli ChenAuthor VitaeMarcel BouvetAuthor Vitae Thibaut SizunAuthor VitaeGuillaume BarochiAuthor Vitae Jérôme RossignolAuthor VitaeEric LesniewskaAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):165-173
A series of new molecular semiconductor-doped insulator (MSDI) heterojunctions as conductimetric transducers to NH3 sensing were fabricated based on a novel semiconducting molecular material, an amphiphilic tris(phthalocyaninato) rare earth triple-decker complex, Eu2[Pc(15C5)4]2[Pc(OC10H21)8], quasi-Langmuir-Shäfer (QLS) film, as a top-layer, and vacuum-deposited and cast film of CuPc as well as copper tetra-tert-butyl phthalocyanine (CuTTBPc) QLS film as a sub-layer, named as MSDIs 1, 2 and 3, respectively. MSDIs 1-3 and respective sub-layers prepared from three different methods were characterized by X-ray diffraction, electronic absorption spectra and current-voltage (I-V) measurements. Depending on the sub-layer film-forming method used, α-phase CuPc film structure, β-phase CuPc crystallites and H-type aggregates of CuTTBPc have been obtained, respectively. An increasing sensitivity to NH3 at varied concentrations in the range of 15-800 ppm, follows the order MSDI 2 < MSDI 3 < MSDI 1, revealing the effect of sub-layer film structures on sensing performance of the MSDIs. In particular, the time-dependent current plot of the MSDI 1, with α-phase CuPc film as a sub-layer, clearly shows an excellent separation of the different ammonia concentration levels and nearly complete reversibility and reproducibility even at room temperature, which is unique among the phthalocyanine-based ammonia sensors thus far reported in the literature. This provides a general method to improve sensor response of organic heterojunctions by controlling and tuning the film structure of sub-layer with appropriate fabrication techniques. On the other hand, the enhanced sensitivity, stability and reproducible response of the MSDI 1 heterostructure in comparison with the respective single-layer films have also been obtained. A judicious combination of materials and molecular architectures has led to enhanced sensing properties of the MSDI 1, in which control at the molecular level can be achieved. 相似文献
62.
D Fesquet JC Labbé J Derancourt JP Capony S Galas F Girard T Lorca J Shuttleworth M Dorée JC Cavadore 《Canadian Metallurgical Quarterly》1993,12(8):3111-3121
Phosphorylation of Thr161, a residue conserved in all members of the cdc2 family, has been reported to be absolutely required for the catalytic activity of cdc2, the major regulator of eukaryotic cell cycle. In the present work, we have purified from starfish oocytes a kinase that specifically activates cdc2 in a cyclin-dependent manner through phosphorylation of its Thr161 residue. Our most highly purified preparation contained only two major proteins of apparent M(r) 37 and 40 kDa (p37 and p40), which could not be separated from each other without loss of activity. The purified kinase was found to phosphorylate not only cdc2, but also cdk2 and a divergent cdc2-like protein from Caenorhabditis, in chimeric complexes including both mitotic and G1/S cyclins. Extensive microsequencing of p40 did not reveal any convincing homology with any known protein. In contrast, p37 is the starfish homologue of the M015 gene product, a kinase previously cloned by homology probing from a Xenopus cDNA library. As expected, immunodepletion of the MO15 protein depleted Xenopus egg extracts of CAK (cdk-activating kinase) activity, which was recovered in immunoprecipitates. Taken together, the above results demonstrate that MO15 is a gene conserved throughout evolution (at least from echinoderms to vertebrates) that encodes the catalytic subunit of a protein kinase that activates cdc2-cdks complexes through phosphorylation of Thr161 (or its homologues). 相似文献
63.
T Schaeverbeke L Lequen B de Barbeyrac L Labbé CM Bébéar Y Morrier B Bannwarth C Bébéar J Dehais 《Canadian Metallurgical Quarterly》1998,41(10):1889-1893
This report describes the case of a patient with a 14-month course of severe oligoarthritis associated with acne. Pure cultures of Propionibacterium acnes were isolated from synovial tissue and synovial fluid specimens collected from the same joint after a 4-month interval. After 2 months of treatment with roxithromycin 300 mg/day, rifampicin 1,200 mg/day, and a nonsteroidal antiinflammatory drug (NSAID), followed by 4 months of treatment with azithromycin 1 gm/week and an NSAID, the synovitis persisted. Cultures of skin lesions and synovial fluid at this time were negative. Although P acnes has previously been isolated from bone specimens obtained from patients with osteitis associated with acne, this is the first report of the isolation of this microorganism from the synovial tissue of a patient with arthritis associated with acne. Our findings raise the question of the role of P acnes in the pathogenesis of arthritis associated with acne. 相似文献
64.
Sporulating and vegetative cell extracts of enterotoxin-positive and enterotoxin-negative strains of Clostridium perfringens were examined by Western blotting using enterotoxin antiserum. A 48-kDa enterotoxin-related protein was found in vegetative and sporulating cell extracts of both toxin types. The results question previous reports about the ability of vegetative cells and presumptive enterotoxin-negative strains of this organism to produce enterotoxin, a protein with a molecular weight of 34 kDa. 相似文献
65.
This work is devoted to a presentation of the ECOCLIMAP-II database for Western Africa, which is an upgrade for this region of the former initiative, ECOCLIMAP-I, implemented at global scale. ECOCLIMAP-II is a dual database at 1-km resolution that comprises an ecosystem classification and a coherent set of land surface parameters. This new physiographic information (e.g. leaf area index, fractional vegetation cover, albedo and land cover classification), was especially developed in the framework of the African Monsoon Multidisciplinary Analysis (AMMA) programme in order to support the modelling of land-atmosphere interactions, which stresses the importance of the present study. Criteria for coherence between prevalent land cover classifications and the analysis of time series of the satellite leaf area index (LAI) between 2000 and 2007 constitute the analysis tools for setting up ECOCLIMAP-II. The LAI and inferred fraction of vegetation cover are spatially distributed per land cover unit. The fraction of vegetation cover is handled to split the land surface albedo into vegetation and bare soil albedo components, as is required for a large number of applications. The new ECOCLIMAP-II land cover product is improved with regard to the spatial coherence compared to former version. The reliability of the physiographic details is also confirmed through verification with land cover products at higher resolution. 相似文献
66.
Armel Thibaut Kaptué Tchuenté Steven M. De Jong Charly Favier 《Remote sensing of environment》2011,115(2):452-464
The goal of this study is to propose a new classification of African ecosystems based on an 8-year analysis of Normalized Difference Vegetation Index (NDVI) data sets from SPOT/VEGETATION. We develop two methods of classification. The first method is obtained from a k-nearest neighbour (k-NN) classifier, which represents a simple machine learning algorithm in pattern recognition. The second method is hybrid in that it combines k-NN clustering, hierarchical principles and the Fast Fourier Transform (FFT). The nomenclature of the two classifications relies on three levels of vegetation structural categories based on the Land Cover Classification System (LCCS). The two main outcomes are: (i) The delineation of the spatial distribution of ecosystems into five bioclimatic ecoregions at the African continental scale; (ii) Two ecosystem maps were made sequentially: an initial map with 92 ecosystems from the k-NN, plus a deduced hybrid classification with 73 classes, which better reflects the bio-geographical patterns. The inclusion of bioclimatic information and successive k-NN clustering elements helps to enhance the discrimination of ecosystems. Adopting this hybrid approach makes the ecosystem identification and labelling more flexible and more accurate in comparison to straightforward methods of classification. The validation of the hybrid classification, conducted by crossing-comparisons with validated continental maps, displayed a mapping accuracy of 54% to 61%. 相似文献
67.
Thibaut SizunAuthor VitaeMarcel BouvetAuthor Vitae Yanli ChenAuthor VitaeJean-Moïse SuisseAuthor Vitae Guillaume BarochiAuthor Vitae Jérôme RossignolAuthor Vitae 《Sensors and actuators. B, Chemical》2011,159(1):163-170
The conductivity of CoPc (cobalt phthalocyanine) and Co[(SO3Na)2,3Pc] was measured under a flow of two different gases (NH3 and O3), during exposure/recovery cycles. It appears that the relative responses are linearly related to the concentration, in the 20-200 ppb range for O3 and in the 20-200 ppm range for NH3. Observed during time, the sensing parameters allow a qualitative understanding of the kinetics. The comparative study of those products under both different gases gave interesting results for sensor applications. Whereas CoPc is sensitive to both gases, its sulfonated counterpart is only sensitive to NH3. 相似文献
68.
Vourc'h G De Garine-Wichatitsky M Labbé A Rosolowski D Martin JL Fritz H 《Journal of chemical ecology》2002,28(12):2411-2427
A previous study showed that Sitka black-tailed deer (Odocoileus hemionus sitkensis) consumption was negatively correlated with monoterpene content in western redcedar (Thuja plicata). To test whether these monoterpenes were deterrent to Sitka black-tailed deer, we performed feeding choice experiments with four hydrocarbon (sabinene, myrcene, -pinene, and d + l-limonene) and one oxygenated (,-thujone) monoterpene solution at their highest natural concentration in western redcedar foliage. To test whether deer response was species specific, we ran similar experiments on European roe deer (Capreolus capreolus) and rusa deer (Cervus timorensis russa). In all experiments, monoterpenes were repellent. Solutions with ,-thujone, the major monoterpene in redcedar leaves, were the most repellent of the solutions tested. We then analyzed how black-tailed and roe deer responded to (1) an increase in concentration of the monoterpenes with the weakest repellent effects (hydrocarbon monoterpenes) and (2) a decrease in concentration of the monoterpene with strongest effect (,-thujone). Repellency tended to increase with concentration for hydrocarbon monoterpenes, but remained strong for ,-thujone. As wild deer regularly feed on plants containing monoterpenes, this raises the question as to how the animals deal with these molecules. 相似文献
69.
Lind E. Allan; Walker Laurens; Kurtz Susan; Musante Linda; Thibaut John W. 《Canadian Metallurgical Quarterly》1980,39(4):643
Examined the effects of outcome on reactions to an adjudication procedure and the effects of procedures on reactions to an adjudication outcome. 111 male undergraduates were led to believe they had been charged with wrongdoing of which they knew they were innocent. The charge was tried, and the Ss outcomes were determined using procedures (adversary or nonadversary) high or low in perceived procedural justice. Ss were then told that they had been found innocent or guilty. Perceptions of the trial process were assessed either before or after the verdict was announced. After the verdict, additional questionnaires assessed perceptions of the verdict and overall perceptions of procedural and distributive fairness. Results show that disputants saw the adversary procedure as fairer than the nonadversary and that they saw the verdict as more fair and satisfying, and as more accurate and unbiased, when it followed an adversary trial. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Bruno Boisseau John Jairo Martinez Thibaut Raharijaona Sylvain Durand Nicolas Marchand 《国际强度与非线性控制杂志
》2017,27(15):2492-2509
》2017,27(15):2492-2509
In this paper, a new event‐switched control method is presented for controlling discrete‐time linear systems subject to bounded disturbances. The main advantage of the proposed method is that the nominal performance of the controlled system with periodic control updates is kept in a framework that do not require to periodically update the control law. The feedback control loop can be opened as long a state‐dependent event condition is satisfied. This condition is obtained using set theory approaches. In particular, the concept of robustly positively invariant sets is used to calculate the nominal performance and the event condition. The simulation presented in this paper confirms the efficiency of the present approach. A reduction of the numerical complexity of the approach is also proposed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献