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Arias J. Kiss P. Prodanov V. Boccuzzi V. Banu M. Bisbal D. Pablo J.S. Quintanilla L. Barbolla J. 《Solid-State Circuits, IEEE Journal of》2006,41(2):339-351
We present an experimental continuous-time complex delta-sigma multi-bit modulator, implemented in standard 0.25-/spl mu/m CMOS technology and meeting all major requirements for application in IEEE 802.11a/b/g wireless LAN receivers. The clock frequency is 320 MHz, producing an oversampling ratio of 16 for 20 MHz channel bandwidths. The modulator supports two operation modes for zero-IF and low-IF receiver architectures respectively, requires a single 2.5-V power supply, and dissipates only 32 mW of power. The measured peak signal-to-noise ratio is 55 dB. Further experimental results using sine-wave and OFDM test signals are also presented. 相似文献
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Low-power pipeline ADC for wireless LANs 总被引:2,自引:0,他引:2
Arias J. Boccuzzi V. Quintanilla L. Enriquez L. Bisbal D. Banu M. Barbolla J. 《Solid-State Circuits, IEEE Journal of》2004,39(8):1338-1340
In this paper, a 10-bit 40-MS/s analog-to-digital converter (ADC) is presented. A power consumption of 12 mW was achieved by using a time-interleaved and pipelined architecture with shared operational amplifiers. This circuit was fabricated in a 2.5-V 0.25-/spl mu/m technology with metal-oxide-metal capacitors. Experimental results are within design ranges and are in good agreement with simulation data. It turns out that the proposed Nyquist-rate ADC provides a potential solution for low-power high-speed applications, e.g., wireless LANs. 相似文献
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A Benoit De Coignac C Bisbal B Lebleu T Salehzada 《Canadian Metallurgical Quarterly》1998,209(1-2):149-156
This study was designed to test the hypothesis that the immune changes seen during in vivo whole body hyperthermia are mediated by elevations in the plasma concentrations of either catecholamines, growth hormone or beta-endorphins. Eight healthy volunteers were immersed in a hot water bath (WI; water temperature 39.5 degrees C) for 2 h during which their rectal temperature rose to 39.5 degrees C. In a single blind, randomized, cross-over study the stress hormone effects were blocked one at a time by administration of propranolol, somatostatin or naloxone; the results were compared to those obtained during saline infusion (control). Blood samples were collected before, at the end of 2 h of WI (body temperature 39.5 degrees C), and 2 h later. Hormone blockade did not abolish the hyperthermia-induced recruitment of natural killer (NK) cells to the blood, and no influence was observed on the percentages or concentrations of any other subpopulations of blood mononuclear cells, except that the number of cluster designation (CD)3+ cells slightly increased after hyperthermia only in the propranolol experiment. Furthermore, the NK cell activity, both unstimulated and interferon-alpha or interleukin-2 stimulated, did not differ from the control situation. It is of interest, however, that somatostatin partly abolished the hyperthermia induced increase in the neutrophil number. Based on these data and previous results showing that growth hormone infusion increases the concentration of neutrophils in the blood, it is suggested that growth hormone is at least partly responsible for hyperthermia induced neutrocytosis. 相似文献
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Roth S Bugnicourt G Bisbal M Gory-Fauré S Brocard J Villard C 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(5):671-675
An approach is developped to gain control over the polarity of neuronal networks at the cellular level by physically constraining cell development by the use of micropatterns. It is demonstrated that the position and path of individual axons, the cell extension that propagates the neuron output signal, can be chosen with a success rate higher than 85%. This allows the design of small living computational blocks above silicon nanowires. 相似文献
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C Martinand C Montavon T Salehzada M Silhol B Lebleu C Bisbal 《Canadian Metallurgical Quarterly》1999,73(1):290-296
The interferon-regulated 2-5A/RNase L pathway plays a major role in the antiviral and antiproliferative activities of these cytokines. Several viruses, however, have evolved strategies to escape the antiviral activity of the 2-5A/RNase L pathway. In this context, we have cloned a cDNA coding for the RNase L inhibitor (RLI), a protein that specifically inhibits RNase L and whose regulated expression in picornavirus-infected cells down regulates the activity of the 2-5A/RNase L pathway. We show here that RLI increases during the course of human immunodeficiency virus type 1 (HIV-1) infection, which may be related to the downregulation of RNase L activity that has been described to occur in HIV-infected cells. In order to establish a possible causal relationship between these observations, we have stably transfected H9 cells with RLI sense or antisense cDNA-expressing vectors. The overexpression of RLI causes a decrease in RNase L activity and a twofold enhancement of HIV production. This increase in HIV replication correlates with an increase in HIV RNA and proteins. In contrast, reduction of RLI levels in RLI antisense cDNA-expressing clones reverses the inhibition of RNase L activity associated with HIV multiplication and leads to a threefold decrease in the viral load. This anti-HIV activity correlated with a decrease in HIV RNA and proteins. These findings demonstrate that the level of RLI, via its modulation of RNase L activity, can severely impair HIV replication and suggest the involvement of RLI in the inhibition of the 2-5A/RNase L system observed during HIV infection. 相似文献
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Fatima Bisbal Jose Vicente Gil Daniel Ramón Pedro Vicente Martínez-Culebras 《European Food Research and Technology》2009,229(5):751-755
In the present study, ochratoxigenic mycobiota in cocoa beans was identified at species level by digestion of the ITS products
using the endonucleases HhaI, NlaIII and RsaI. Of the 132 isolates of Aspergillus section Nigri collected from cocoa beans, 89 were identified as A. tubingensis, 27 as A. niger, 10 as A. tubingensis-like and 6 as A. carbonarius. No variation was observed between RFLP patterns (C, N, T1 and T2) described previously for grape isolates and those of the
cocoa isolates analysed. With respect to OTA-producing fungi, a high percentage of black aspergilli (50.7%) was able to produce
OTA. Additionally, most of the OTA-producing isolates were of moderate toxigenicity, producing amounts of OTA from 10 μg g−1 to 100 μg g−1. Percentages of OTA-producing isolates in the A. niger aggregate were higher than in other substrates, ranging from 30% to 51.7%. Furthermore, the detected levels of OTA production
in the A. niger aggregate, particularly in A. tubingensis species was higher than in A. carbonarius, ranging from 0.7 μg g−1 to 120 μg g−1 (mean 24.55 μg g−1). Due to the high occurrence, percentage of ocratoxigenic isolates and their ability to produce OTA, isolates belonging to
the A. niger aggregate could be considered as the main cause of OTA contamination in cocoa beans used for manufacturing cocoa products. 相似文献
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A legacy information system represents a massive, long-term business investment. Unfortunately, such systems are often brittle, slow and non-extensible. Capturing legacy system data in a way that can support organizations into the future is an important but relatively new research area. The authors offer an overview of existing research and present two promising methodologies for legacy information system migration 相似文献
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Dynamic Routing and Wavelength Assignment in Optical Networks by Means of Genetic Algorithms 总被引:2,自引:0,他引:2
Bisbal David Miguel Ignacio de González Fernando Blas Juan Aguado Juan Carlos Fernández Patricia Durán Javier Durán Ramón Lorenzo Rubén M. Abril Evaristo J. López Miguel 《Photonic Network Communications》2004,7(1):43-58
We propose a novel genetic algorithm for solving the dynamic routing and wavelength assignment (DRWA) problem in wavelength-routed optical networks. The algorithm not only obtains low call blocking probability, but it also employs a very short computation time. Moreover, it is capable of providing fairness among connections, that is, to offer approximately the same quality of service (in terms of blocking probability) for all source-destination node pairs. Since requirements on optical network availability are highly severe, we also propose an extension of the algorithm to provide fault-tolerance capability at the optical layer. It is achieved by means of protection, where each optical connection request is provided with a pair of lightpaths (a primary and a backup lightpath). Again, the genetic algorithm proves to be highly efficient, in this case, at performing routing and wavelength assignment of pairs of lightpaths. 相似文献
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Arias J. Kiss P. Boccuzzi V. Quintanilla L. Enriquez L. Vicente J. Bisbal D. Pablo J.S. Barbolla J. 《IEEE transactions on circuits and systems. I, Regular papers》2005,52(6):1033-1041
This paper presents a digital correction technique for wide-band multibit error-feedback (EF) digital-to-analog converters (DACs). The integral nonlinearity (INL) error of the multibit DAC is estimated (on line or off line) by a calibration analog-to-digital converter (CADC) and stored in a random-access memory table. The INL values are then used to compensate for the multibit DAC's distortion by a simple digital addition. The accuracy requirements for the error estimates are derived. These requirements can be significantly relaxed when the correction is combined with data-weighted averaging (DWA). Simulation and discrete-component measurement results are presented for a fourth-order 5-bit EF DAC. The results show a 14-bit DAC operating at an oversampling ratio of 8, which is suitable for digital subscriber line applications. The correction uses simple digital circuitry and a 3-bit CADC enhanced by DWA. 相似文献
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