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991.
Pablo Espinet 《Gold bulletin》1999,32(4):127-134
The simple linear coordination of gold(I) helps in the understanding of structure-property relationships in liquid crystals based on metal-containing molecules. This simple geometry also allows the preparation of materials showing a range of mesophases, based on both rod-like and disc-like molecules. 相似文献
992.
Germán D. Schrott P. Sebastian Bonanni Luciana Robuschi Abraham Esteve-Nuñez Juan Pablo Busalmen 《Electrochimica acta》2011,(28):10791
Electroactive bacterial biofilms can be produced on a polarized electrode by forcing its use as the final electron acceptor for bacterial respiration. This strategy offers the researcher the unique possibility to control the respiration process with extreme precision. The production of current, the accumulation of charge and the conducting properties of electroactive biofilms has been interrogated in this work through very basic electrochemical techniques including chronopotentiometry, chronoamperometry and cyclic voltammetry. Presented results indicate that charge can be accumulated in the biofilm conductive network, that network conductivity does not represent a limit for current production and that both the steady state current and the amount of accumulated charge depend on the redox state of cytochromes wiring the cells to the electrode. A model of biofilm conduction is presented as well. 相似文献
993.
David D. Allen Raúl Caviedes Ana María Cárdenas Takeshi Shimahara Juan Segura-Aguilar Pablo A. Caviedes 《Drug development and industrial pharmacy》2013,39(8):757-768
ABSTRACTCell culture is highly desirable, as it provides systems for ready, direct access and evaluation of tissues. The use of tissue culture is a valuable tool to study problems of clinical relevance, especially those related to diseases, screening, and studies of cell toxicity mechanisms. Ready access to the cells provides the possibility for easy studies of cellular mechanisms that may suggest new potential drug targets and, in the case of pathological-derived tissue, it has an interesting application in the evaluation of therapeutic agents that potentially may treat the dysfunction. However, special considerations must be addressed to establish stable in vitro function. In primary culture, these factors are primarily linked to greater demands of tissue to adequately survive and develop differentiated conditions in vitro. Additional requirements include the use of special substrates (collagen, laminin, extracellular matrix preparations, etc.), growth factors and soluble media supplements, some of which can be quite complex in their composition. These demands, along with difficulties in obtaining adequate tissue amounts, have prompted interest in developing immortalized cell lines which can provide unlimited tissue amounts. However, cell lines tend to exhibit problems in stability and/or viability, though they serve as a feasible alternative, especially regarding new potential applications in cell transplant therapy. In this regard, stem cells may also be a source for the generation of various cell types in vitro. This review will address aspects of cell culture system application, with focus on immortalized cell lines, in studying cell function and dysfunction with the primary aim being to identify cell targets for drug screening. 相似文献
994.
995.
Pablo Basanta‐Val Marisol García‐Valls Iria Estvez‐Ayres Jorge Fernndez‐Gonzlez 《Concurrency and Computation》2011,23(11):1236-1260
The proliferation of a new generation of distributed real‐time embedded systems (DRE) characterized by special restrictions on its storage capacities, its available computation time, and the messages they can send through the network suggests a comprehensive redesign of the current distribution infrastructure in order to tune its performance. In this changing panorama, the paper concerns one of the protocols, Java's Remote Method Protocol (JRMP), used nowadays to interconnect different nodes of a distributed Java system, and explores the cost of integrating an improved protocol‐level multiplexing strategy in the context of an end‐to‐end remote invocation. The new multiplexing strategy helps middleware manage more efficiently unscheduled invocations that appear at runtime generated from a certain client node, especially in cases where preallocation of resources or dimensioning for the worst‐case are techniques not plausible. To this end, the paper examines an alternative based on the definition of a new subprotocol, called ConnectionLess, which offers built‐in multiplexing facilities for distributed Java applications. The performance of the new subprotocol is compared against the three already defined by JRMP (namely SingleOp, Stream, and Multiplex), taking into consideration parameters such as memory consumed in the Java's virtual machine and end‐to‐end response times. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
996.
In this paper, we present a real life assembly line balancing problem for a motorcycle manufacturing company. Results from the initial situation in the company are compared to those provided by a heuristic method and by a novel neighbourhood search method. An ARENA simulation model is developed to test the different proposals. The model was validated by comparing the simulation results from the initial company scenario with the real operation results. Consequently, the extension to the developed proposals allows us to select an adequate assembly line for the company, resulting in a greater productivity level and a more balanced line with respect to the operation times in the stations and the activity of the workers. The company has subsequently implemented our proposed schedule, obtaining remarkable improvements in its productivity. 相似文献
997.
Chenchen Bao Nicolas Beziere Pablo del Pino Beatriz Pelaz Giovani Estrada Furong Tian Vasilis Ntziachristos Jesus M. de la Fuente Daxiang Cui 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(1):68-74
Early detection of cancer greatly increases the chances of a simpler and more effective treatment. Traditional imaging techniques are often limited by shallow penetration, low sensitivity, low specificity, poor spatial resolution or the use of ionizing radiation. Hybrid modalities, like optoacoustic imaging, an emerging molecular imaging modality, contribute to improving most of these limitations. However, this imaging method is hindered by relatively low signal contrast. Here, gold nanoprisms (AuNPrs) are used as signal amplifiers in multispectral optoacoustic tomography (MSOT) to visualize gastrointestinal cancer. PEGylated AuNPrs are successfully internalized by HT‐29 gastrointestinal cancer cells in vitro. Moreover, the particles show good biocompatibility and exhibit a surface plasmon band centered at 830 nm, a suitable wavelength for optoacoustic imaging purposes. These findings extend well to an in vivo setting, in which mice are injected with PEGylated AuNPrs in order to visualize tumor angiogenesis in gastrointestinal cancer cells. Overall, both our in vitro and in vivo results show that PEGylated AuNPrs have the capacity to penetrate tumors and provide a high‐resolution signal amplifier for optoacoustic imaging. The combination of PEGylated AuNPrs and MSOT represents a significant advance for the in vivo imaging of cancers. 相似文献
998.
Policy schemes,operational strategies and system integration of residential co-generation fuel cells
Lise-Lotte Pade Sascha Thorsten Schröder Marie Münster Christoph Birkl Stephanie Ropenus Poul Erik Morthorst Elisabeth Obé Editha Kötter Andreas Huber Ana Costa Pablo Kroff 《International Journal of Hydrogen Energy》2013
This study presents a holistic approach for the commercialisation of fuel cells for stationary applications. We focus our analyses on microCHP based on SOFC units fired with natural gas. We analyse the interaction of operational strategies under different ownership arrangements, required support levels and system integration aspects. The operational strategies, support mechanisms and ownership arrangements have been identified through actor analysis involving experts from Denmark, France and Portugal. With regard to operational strategies, the actor analyses led us to distinguishing between a heat-driven strategy, with and without time-differentiated tariffs, and an electricity price driven strategy for the operation as a virtual power plant. The corresponding support schemes identified cover feed-in tariffs, net metering and feed-in premiums. Additionally, the interplay of the microCHP units with the national energy systems has been analysed. Our main findings are that net metering would be an appropriate tool to support FC based microCHP in Denmark, whereas a price premium would be the preferable tool in France and Portugal. 相似文献
999.
Pablo García Juan P. Torreglosa Luis M. Fernández Francisco Jurado 《International Journal of Hydrogen Energy》2013
This paper presents a novel hourly energy management system (EMS) for a stand-alone hybrid renewable energy system (HRES). The HRES is composed of a wind turbine (WT) and photovoltaic (PV) solar panels as primary energy sources, and two energy storage systems (ESS), which are a hydrogen subsystem and a battery. The WT and PV panels are made to work at maximum power point, whereas the battery and the hydrogen subsystem, which is composed of fuel cell (FC), electrolyzer and hydrogen storage tank, act as support and storage system. The EMS uses a fuzzy logic control to satisfy the energy demanded by the load and maintain the state-of-charge (SOC) of the battery and the hydrogen tank level between certain target margins, while trying to optimize the utilization cost and lifetime of the ESS. Commercial available components and an expected life of the HRES of 25 years were considered in this study. Simulation results show that the proposed control meets the objectives established for the EMS of the HRES, and achieves a total cost saving of 13% over other simpler EMS based on control states presented in this paper. 相似文献
1000.
Elvira Oñorbe Ph. D. Gerardo Garcés Ferdinand Dobes Pablo Pérez Paloma Adeva 《Metallurgical and Materials Transactions A》2013,44(6):2869-2883
The high-temperature mechanical behavior of extruded Mg97?3x Y2x Zn x (at. pct) alloys is evaluated from 473 K to 673 K (200 °C to 400 °C). The microstructure of the extruded alloys is characterized by Long Period Stacking Ordered structure (LPSO) elongated particles within the magnesium matrix. At low temperature and high strain rates, their creep behavior shows a high stress exponent (n = 11) and high activation energy. Alloys behave as a metal matrix composite where the magnesium matrix transfers part of its load to the LPSO phase. At high-temperature and/or low stresses, creep is controlled by nonbasal dislocation slip. At intermediate and high strain rates at 673 K (400 °C) and at intermediate strain rates between 623 K and 673 K (350 °C and 400 °C), the extruded alloys show superplastic deformation with elongations to failure higher than 200 pct. Cracking of coarse LPSO second-phase particles and their subsequent distribution in the magnesium matrix take place during superplastic deformation, preventing magnesium grain growth. 相似文献