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81.
F. J. Exposito J. P. Diaz M. Arbelo F. Herrera J. C. Guerra 《International journal of remote sensing》2013,34(10):2247-2252
The aerosol optical depth data obtained by two methods are compared. The first method uses solar radiance measurements with the spectroradiometer Optronic OL752 installed inside the Santa Cruz de Tenerife Harbour (28.48 N, 16.24 W). The second one takes the solar radiation scattered by the atmosphere using the Advanced Very High Resolution Radiometer (AVHRR) radiometer channels on board the NOAA meteorological satellites. A 91 per cent correlation between the two procedures was obtained for channel 1 (630nm). 相似文献
82.
DL Williams L Spring L Collins LP Miller LB Heifets PR Gangadharam TP Gillis 《Canadian Metallurgical Quarterly》1998,42(7):1853-1857
The contributions of 23 insertion, deletion, or missense mutations within an 81-bp fragment of rpoB, the gene encoding the beta-subunit of the DNA-dependent RNA polymerase of Mycobacterium tuberculosis, to the development of resistance to rifamycins (rifampin, rifabutin, rifapentine, and KRM-1648) in 29 rifampin-resistant clinical isolates were defined. Specific mutant rpoB alleles led to the development of cross-resistance to all rifamycins tested, while a subset of mutations were associated with resistance to rifampin and rifapentine but not to KRM-1648 or rifabutin. To further study the impact of specific rpoB mutant alleles on the development of rifamycin resistance, mutations were incorporated into the rpoB gene of M. tuberculosis H37Rv, contained on a mycobacterial shuttle plasmid, by in vitro mutagenesis. Recombinant M. tuberculosis clones containing plasmids with specific mutations in either codon 531 or 526 of rpoB exhibited high-level resistance to all rifamycins tested, whereas clones containing a plasmid with a mutation in codon 516 exhibited high-level resistance to rifampin and rifapentine but were susceptible to both rifabutin and KRM-1648. These results provided additional proof of the association of specific rpoB mutations with the development of rifamycin resistance and corroborate previous reports of the usefulness of rpoB genotyping for predicting rifamycin-resistant phenotypes. 相似文献
83.
GR Login M Aoki M Yamakawa LO Lunardi EC Digenis N Tanda LB Schwartz AM Dvorak 《Canadian Metallurgical Quarterly》1997,45(10):1379-1391
The subcellular events responsible for release of mediators by mast cells may help to clarify roles for mast cells in health and disease. In this study we show that the granule-associated protease chymase is also within cytoplasmic vesicles in appropriately stimulated rat peritoneal mast cells. Rat peritoneal mast cells were recovered before or 1-10 sec after exposure to the secretogogue compound 48/80 (10 micrograms/ml) and then were examined by radioimmunoassay to quantify histamine release or were processed, using routine methods for postembedding immunoelectron microscopy, to identify the subcellular localization of chymase. In comparison to unstimulated cells, compound 48/80 stimulated cells in two independent experiments showed an increase (15%, 28%) in the surface area of the cell and a decrease (12%, 6%) in the surface area of the total granule compartment before degranulation channel formation. These global cellular changes occurred in a background of transient but significant (p < 0.01) increases in the area and number of chymase-immunoreactive vesicles per microns2 cytoplasm. These changes were detectable at 5 or 7 sec after stimulation with compound 48/80 but returned to near prestimulation levels by 9 or 10 sec after addition of compound 48/80 (total cumulative histamine release was 28% by 8 sec and 47% by 14 sec). These observations suggest that vesicles participate in the early stages of regulated secretion of chymase from rat peritoneal mast cells. 相似文献
84.
85.
LB Lane 《Canadian Metallurgical Quarterly》1993,18(2):366-368
The scaphoid test described by Watson has generally been accepted as the definitive test for scaphoid instability and uses pressure against the scaphoid tubercle as the wrist moves from ulnar to radial deviation for the evaluation. This article describes a stress test done with the wrist in neutral position, which actively provokes scaphoid instability. Variations in stability can be used to grade scaphoid laxity. 相似文献
86.
RM Strand AO M?lster LB Engesaeter NR Gjerdet T Orner 《Canadian Metallurgical Quarterly》1998,117(1-2):35-38
Treatments of Chinese hamster V79 cells during one cell cycle with a new type of topoisomerase II inhibitor, ICRF-193, which does not accumulate cleavable topoisomerase-DNA complexes induced both chromosome- and chromatid-type aberrations with high frequencies. Furthermore, ICRF-193 synergistically enhanced the yield of UVB-induced chromatid-type aberrations, chromatid exchanges in particular. Treated with ICRF-193 for the last 3 h before harvest, cells showed frequent incidence of chromatid-type aberrations and synergistic enhancement of UVB-induced chromatid-type aberrations, chromatid exchanges in particular. These results suggest that spontaneous and UVB-induced lesions might be ultimately transformed into chromatid-type aberrations by topoisomerase II-dependent checkpoint process(es) in the G2 phase of the cell cycle. 相似文献
87.
Sanaz Paran Tuyen Vu Fernand Diaz Chris S. Edrington Touria El-Mezyani 《电力部件与系统》2019,47(16-17):1437-1449
AbstractPower scheduling of distributed storage devices and renewable energy resources in microgrids is crucial for their reliable and optimal operation. Conventionally, the power scheduling problem is solved with a centralized energy management control, which has access to all the information from the overall system. This type of control has limitations related to computational burden, communication latencies, and missing information. Therefore, the primary objective of this paper is to propose a distributed energy management strategy, to reduce the operational cost of microgrids, and to enhance the computation time. The strategy is formulated based on the model predictive control method since it allows the control action in the current time-step to be optimized while taking into account the future time-steps. Outputs of the energy management system are the optimal power references generated for all energy resources based on the system’s demand, constraints, and objective functions. To illustrate the effectiveness of the distributed model predictive control, the proposed algorithm is validated through simulation, on a microgrid candidate via MATLAB/Simulink, and controller hardware-in-the-loop experiment on a LabVIEW platform using National Instruments control devices (myRIO). The results will show the computation time in the distributed IEM method is improved compared to centralized IEM. Additionally, the results will show the robustness of the distributed IEM in the plug and play scenario. 相似文献
88.
Xavi Masip-Bruin Marcelo Yannuzzi Rene Serral-Gracia Jordi Domingo-Pascual Jose Enriquez-Gabeiras Maria Angeles Callejo Michel Diaz Florin Racaru Giovanni Stea Enzo Mingozzi Andrzej Beben Wojciech Burakowski Edmundo Monteiro Luís Cordeiro 《Communications Magazine, IEEE》2007,45(2):96-103
EuQoS is the acronym for "end-to-end quality of service support over heterogeneous networks", which is a European research project aimed at building an entire QoS framework, addressing all the relevant network layers, protocols, and technologies. This framework, which includes the most common access networks (xDSL, UMTS, WiFi, and LAN) is being prototyped and tested in a multidomain scenario throughout Europe, composing what we call the EuQoS system. In this article we present the novel QoS routing mechanisms that are being developed and evaluated in the framework of this project. The preliminary performance results validate the design choices of the EuQoS system, and confirm the potential impact this project is likely to have in the near future 相似文献
89.
We address restoration of eutrophic lakes and reservoirs through the formulation of dynamic optimization problems subject to complex PDAE systems representing biogeochemical processes in the water bodies. The model includes phytoplankton, zooplankton, fish, nutrients, DO, particulate and dissolved carbon dynamics. The PDAE has been transformed into an ordinary differential algebraic equation system by spatial discretization into two water layers. An optimal control problem for the implementation of three different restoration techniques and their combinations has been formulated within a control vector parameterization approach. Numerical results for the different problems provide optimal profiles for tributary deviation flowrate through a nearby wetland, aeration rates and fish removal rates, as restoration strategies. 相似文献
90.
Julia E. Tasca Agustín Ponzinibbio Gisela Diaz Rodolfo D. Bravo Araceli Lavat María G. González 《Topics in Catalysis》2010,53(15-18):1087-1090
An efficient protocol for the rapid room temperature deacetylation of carbohydrate derivatives using CuFe2O4 nanoparticles as an inexpensive and reusable catalyst is presented. After separation of the catalyst with an external magnet, the reaction products are easily obtained in good purity and excellent yields. 相似文献