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991.
Solution structure of human corticotropin releasing factor by 1H NMR and distance geometry with restrained molecular dynamics 总被引:1,自引:0,他引:1
Romier Christophe; Bernassau Jean-Marie; Cambillau Christian; Darbon Herve 《Protein engineering, design & selection : PEDS》1993,6(2):149-156
The structure of human corticotropin releasing factor (hCRF)has been determined by proton nuclear magnetic resonance (1HNMR) in a mixed-solvent system of 66% trifluoroethanol/34% H2Oat pH 3.8 and 37°C. Nearly complete resonance assignmentwas achieved by using standard two-dimensional methods. Distancerestraints for structure calculations were obtained by qualitativeanalysis of intra- and interresidue nuclear Overhauser effects.Structures were obtained from the distance restraints by distancegeometry, followed by refinement using molecular dynamics andwere completed with amide hydrogen exchange data. The structureof hCRF in this solvent comprises an extended N-terminal tetrapeptideconnected to a well-defined -helix between residues 6 and 36.The first half of the -helix (residues 620) is clearlyamphipathic. The five carboxy-terminal residues are predominantlydisordered. 相似文献
992.
The Effects of Electronic Impurities and Electron–Hole Recombination Dynamics on Large‐Grain Organic–Inorganic Perovskite Photovoltaic Efficiencies
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Jean‐Christophe Blancon Wanyi Nie Amanda J. Neukirch Gautam Gupta Sergei Tretiak Laurent Cognet Aditya D. Mohite Jared J. Crochet 《Advanced functional materials》2016,26(24):4283-4292
Hybrid organic‐inorganic perovskites have attracted considerable attention after promising developments in energy harvesting and other optoelectronic applications. However, further optimization will require a deeper understanding of the intrinsic photophysics of materials with relevant structural characteristics. Here, the dynamics of photoexcited charge carriers in large‐area grain organic‐inorganic perovskite thin films is investigated via confocal time‐resolved photoluminescence spectroscopy. It is found that the bimolecular recombination of free charges is the dominant decay mechanism at excitation densities relevant for photovoltaic applications. Bimolecular coefficients are found to be on the order of 10?9 cm3 s?1, comparable to typical direct‐gap semiconductors, yet significantly smaller than theoretically expected. It is also demonstrated that there is no degradation in carrier transport in these thin films due to electronic impurities. Suppressed electron–hole recombination and transport that is not limited by deep level defects provide a microscopic model for the superior performance of large‐area grain hybrid perovskites for photovoltaic applications. 相似文献
993.
Antonio Carlos Padoan Jr. ;Christophe Nicolet ;Basile Kawkabani ;Jean-Jacques Simond ;Alexander Schwery ;Francois Avellan 《能源与动力工程:英文版》2014,(8):1449-1459
This paper presents the modelling, simulation and analysis of the dynamic behaviour of a mixed power network of 2.78 GW including hydro, thermal and wind power plants. The modelling of each power plant is described. The set of parameters of the turbine speed governor of the hydroelectric power plant is determined with a specific identification procedure to achieve stable operation for different cases such as interconnected, isolated or islanded operation. The analysis of the stability of the entire mixed islanded power plant is investigated through time domain simulations for different sets of controllers parameters and for different disturbances (load rejection and turbulent wind speed profile). 相似文献
994.
Alessandro Spagnolo Philippe Larignon Maryline Magnin-Robert Agnès Hovasse Clara Cilindre Alain Van Dorsselaer Christophe Clément Christine Schaeffer-Reiss Florence Fontaine 《International journal of molecular sciences》2014,15(6):9644-9669
Botryosphaeria dieback is a fungal grapevine trunk disease that currently represents a threat for viticulture worldwide because of the important economical losses due to reduced yield of affected plants and their premature death. Neofusicoccum parvum and Diplodia seriata are among the causal agents. Vine green stems were artificially infected with N. parvum or D. seriata at the onset of three different phenological stages (G stage (separated clusters), flowering and veraison). Highest mean lesion lengths were recorded at flowering. Major proteome changes associated to artificial infections during the three different phenological stages were also reported using two dimensional gel electrophoresis (2D)-based analysis. Twenty (G stage), 15 (flowering) and 13 (veraison) differentially expressed protein spots were subjected to nanoLC-MS/MS and a total of 247, 54 and 25 proteins were respectively identified. At flowering, a weaker response to the infection was likely activated as compared to the other stages, and some defense-related proteins were even down regulated (e.g., superoxide dismutase, major latex-like protein, and pathogenesis related protein 10). Globally, the flowering period seemed to represent the period of highest sensitivity of grapevine to Botryosphaeria dieback agent infection, possibly being related to the high metabolic activity in the inflorescences. 相似文献
995.
Holly C. Miller Sébastien Kubicki Delphine Caffier Christophe Kolski 《International journal of human-computer interaction》2016,32(5):363-372
An interactive tabletop equipped with RFID technology implemented the Stroop and reverse-Stroop tasks. Participants moved a tangible object into one of four displayed virtual zones, which were identified either by a color border or the name of a color written in black. The correct target zone corresponded either to the color (Stroop) or meaning (reverse Stroop) of a word displayed in congruent or incongruent colored LED lights (e.g., “YELLOW” displayed in yellow or red, respectively). Participants took more time to place the object in a zone, made more errors, and found the task more difficult when the word was lit with an incongruent than congruent color. This interference was influenced by both the types of task and response zone in a way that fits with a dual step processing account. Results also showed that the outcomes of the conflicting information streams might be judged as fun. 相似文献
996.
997.
Liviu S. Enache Elena L. Enache Christophe Ramière Olivier Diaz Ligia Bancu Anca Sin Patrice André 《International journal of molecular sciences》2014,15(10):17644-17666
Liver disease is a major cause of morbidity and mortality worldwide. As in other fields of medicine, there is a stringent need for non-invasive markers to improve patient diagnostics, monitoring and prognostic ability in liver pathology. Cell-free circulating RNA molecules have been recently acknowledged as an important source of potential medical biomarkers. However, many aspects related to the biology of these molecules remain to be elucidated. In this review, we summarize current concepts related to the origin, transportation and possible functions of cell-free RNA. We outline current development of extracellular RNA-based biomarkers in the main forms of non-inherited liver disease: chronic viral hepatitis, hepatocellular carcinoma, non-alcoholic fatty liver, hepato-toxicity, and liver transplantation. Despite recent technological advances, the lack of standardization in the assessment of these markers makes their adoption into clinical practice difficult. We thus finally review the main factors influencing quantification of circulating RNA. These factors should be considered in the reporting and interpretation of current findings, as well as in the proper planning of future studies, to improve reliability and reproducibility of results. 相似文献
998.
Bimodal X‐ray and Infrared Imaging of an Organometallic Derivative of Praziquantel in Schistosoma mansoni
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Dr. Sylvain Clède Noemi Cowan Dr. François Lambert Dr. Hélène C. Bertrand Dr. Riccardo Rubbiani Dr. Malay Patra Jeannine Hess Dr. Christophe Sandt Dr. Nicolas Trcera Prof. Dr. Gilles Gasser Prof. Dr. Jennifer Keiser Prof. Dr. Clotilde Policar 《Chembiochem : a European journal of chemical biology》2016,17(11):1004-1007
An organometallic derivative of praziquantel was studied directly in worms by using inductively coupled plasma‐mass spectrometry (ICP‐MS) for quantification and synchrotron‐based imaging. X‐ray fluorescence (XRF) and IR absorption spectromicroscopy were used for the first time in combination to directly locate this organometallic drug candidate in schistosomes. The detection of both CO (IR) and Cr (XRF) signatures proved that the Cr(CO)3 core remained intact in the worms. Images showed a preferential accumulation at the worm's tegument, consistent with a possible targeting of the calcium channel but not excluding other biological targets inside the worm. 相似文献
999.
Benthic microbial fuel cells (BMFCs) are continuous electricity generators using electroactive microorganisms and organic matter from aquatic environment, respectively, as catalysts and substrate. In this paper, first a low‐cost PVC‐made structure is constructed to harvest electricity from mangrove environment located in French Guiana. An in situ BMFC has given power density of 30 mW/m2 of the anodic surface area. This performance has been confirmed by experience in laboratory where inter‐electrode distance and electrode surface area appeared to be power increasing factors. However, the output power of one BMFC is not used to supply real devices such as autonomous sensors. Second, to meet this expectation, in parallel and in series associations were considered. These associations were made in order to increase the output voltage and consequently the power, to reach levels that can supply small sensors (about 3 V). Finally, to improve the performance of the series association and to avoid the voltage reversal phenomenon, a voltage balancing circuit was simulated and added to the series connections. With balancing method, the cell voltage of BMFCs can be equalized, and the performances can be improved. This allows an optimal energy harvesting and a better global efficiency of the set. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
1000.