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991.
K Sermon W Lissens L Messiaen M Bonduelle M Vandervorst A Van Steirteghem I Liebaers 《Canadian Metallurgical Quarterly》1999,71(1):163-166
OBJECTIVE: To develop and apply clinical preimplantation genetic diagnosis (PGD) for Marfan syndrome. DESIGN: Case report. SETTING: Centers for medical genetics and reproductive medicine in university hospitals. PATIENT(S): One couple in which the husband was affected with Marfan syndrome. INTERVENTION(S): The couple underwent three intracytoplasmic sperm injection cycles. MAIN OUTCOME MEASURE(S): The correct diagnosis was obtained for embryos in three PGD cycles. RESULT(S): Although all the PGD cycles were followed by ET, no pregnancy ensued. CONCLUSION(S): This assay can provide a reliable and accurate preimplantation diagnosis of Marfan syndrome. 相似文献
992.
Simon Dan; Pham Lien B.; Le Quang A.; Holyoak Keith J. 《Canadian Metallurgical Quarterly》2001,27(5):1250
Previous research has indicated that decision making is accompanied by an increase in the coherence of assessments of the factors related to the decision alternatives. In the present study, the authors investigated whether this coherence shift is obtained before people commit to a decision, and whether it is obtained in the course of a number of other processing tasks. College students were presented with a complex legal case involving multiple conflicting arguments. Participants rated agreement with the individual arguments in isolation before seeing the case and after processing it under various initial sets, including playing the role of a judge assigned to decide the case. Coherence shifts were observed when participants were instructed to delay making the decision (Experiment 1), to memorize the case (Experiment 2), and to comprehend the case (Experiment 3). The findings support the hypothesis that a coherence-generating mechanism operates in a variety of processing tasks, including decision making. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Three UASB reactors were operated at different salinity levels in order to assess the effects on the granular sludge properties. High levels of activity inhibition were observed at sodium concentrations over 7 g Na(+)/L, which resulted in low applicable organic loading rates and VFA accumulation in reactor effluents. However, either sludge adaptation or selection for saline resistant microorganisms occurred, which could be concluded from the observed increase in the 50% activity inhibitory concentrations of sodium during continuous flow experiments. Changes in Na(+) susceptibility in time are likely to be expected when treating saline wastewaters. The latter was evidenced by the high sodium tolerance of granular methanogenic sludge coming from a full-scale industrial reactor treating such wastewater. High salinity conditions resulted in a reduced granule strength, predicting process instabilities during long term reactor operation. Batch tests showed that high sodium concentrations seemed to displace the calcium from the granular sludge, a factor known to affect anaerobic granules formation. 相似文献
994.
Min Li David Novo Bruno Bougard Claude Desset Antoine Dejonghe Liesbet Van Der Perre Francky Catthoor 《Journal of Signal Processing Systems》2011,63(1):13-25
The fast pacing diversity and evolution of wireless communications require a wide variety of baseband implementations within
a short time-to-market. Besides, the exponentially increased design complexity and design cost of deep sub-micron silicon
highly desire the designs to be reused as much as possible. This yields an increasing demand for reconfigurable/ programmable
baseband solutions. Implementing all baseband functionalities on programmable architectures, as foreseen in the tier-2 SDR,
will become necessary in the future. However, the energy efficiency of SDR baseband platforms is a major concern. This brings
a challenging gap that is continuously broadened by the exploding baseband complexity. We advocate a system level approach
to bridge the gap. Specifically, we fully leverage the advantages (programmability) of SDR platforms to compensate its disadvantages
(energy efficiency). Highly flexible and dynamic baseband signal processing algorithms are designed and implemented to exploit
the abundant dynamics in the environment and the user requirement. Instead of always performing the best effort, the baseband
can dynamically and autonomously adjust its work load to optimize the average energy consumption. In this paper, we will introduce
such baseband signal processing techniques optimized for SDR implementations. The methodology and design steps will be presented
together with 3 representative case studies in HSDPA, WiMAX and 3GPP LTE. 相似文献
995.
996.
Neil D. Hurley William H. Van Geertruyden Wojciech Z. Misiolek 《Journal of Materials Processing Technology》2009,209(18-19):5990-5995
During hot deformation of Al–Mg–Si alloys, a non-uniform microstructure is developed due to differences in localized strain. Physical simulations were performed to examine the effects of processing parameters such as deformation temperature, total reduction, rolling schedule and alloying additions on the grain structure evolution. Overall, the kinetics of recrystallization followed the traditional trends predicted by JMAK kinetics. Electron backscatter diffraction (EBSD) was used to quantify the difference in recrystallization kinetics at the sample surface and mid-thickness. The results showed that the surface showed elevated kinetics when compared to the sample mid-thickness. 相似文献
997.
M P De Jong M J A De Voigt L J Van Ijzendoorn H H Brongersma 《Bulletin of Materials Science》1999,22(3):687-690
Nuclear analytical techniques (PIXE, RBS and ERDA) have been applied to investigate diffusion processes in polymer light-emitting
diodes (PLEDs), employing a 30 MeV AVF cyclotron. The techniques prove to be useful in identifying the origin of the diffusion
process and the nature of molecules transported from the hole injecting ITO electrode into the polymer layer. 相似文献
998.
Van Engelen J.A.E.P. Van De Plassche R.J. Stikvoort E. Venes A.G. 《Solid-State Circuits, IEEE Journal of》1999,34(12):1753-1764
This paper presents a sixth-order continuous-time bandpass sigma-delta modulator (SDM) for analog-to-digital conversion of intermediate-frequency signals. An important aspect in the design of this SDM is the stability analysis using the describing function method. The key to the analysis is the extension of the linear gain model for the sampled quantizer with a phase uncertainty. The single-loop, one-bit SDM is tuned at 10.7 MHz, is sampled at 40 MHz, and achieves 67-dB signal-to-(noise+distortion) ratio in 200 kHz and 80 dB in 9 kHz. The third order intermodulation is at -82 dBc for a -13-dBFS input level. The 0.5-μm CMOS chip occupies 0.9×0.4 mm2 and consumes 60 mW at 3.3 V (digital) and 5.0 V (analog). The sample frequency is variable and can be set from 30 to 80 MHz 相似文献
999.
H Morales P Tilquin JF Rees A Massip F Dessy A Van Langendonckt 《Canadian Metallurgical Quarterly》1999,52(2):149-157
The impact of oxidative stress on the in vitro development of bovine embryos in synthetic oviduct fluid medium (mSOF) was assessed by using H2O2 as a stress inducer. In a preliminary experiment, a chemiluminescent method was used to measure the antioxidative capacity of the mSOF culture medium. Pyruvate was the mSOF component displaying the highest H2O2 degrading ability. Essential and nonessential amino acids also significantly reduced the H2O2 concentration, whereas lactate and glutamine were ineffective. The effect on further development of a short exposure of zygotes, 9-16-cell stage embryos and blastocysts to 0 M; 10(-7) M ; 10(-6) M, and 10(-5) M H2O2 in pyruvate-free mSOF was evaluated. Developmental rates of the H2O2-treated zygotes to the 5-8-cell or blastocyst stages and survival of H2O2-treated blastocysts were reduced in a dose-dependent manner whereas the 9-16-cell embryos were unaffected by those treatments. Blastocysts treated with H2O2 also tended to have lower numbers of bisbenzimide-stained nuclei and showed increased nuclear fragmentation. Including pyruvate in the mSOF culture medium during a 10(-5) M H2O2 pulse highly reduced the H2O2 concentration as measured by chemiluminescence and improved zygote and blastocyst development, but failed to prevent blastocyst nuclei degradation. These experiments suggest that bovine embryos show developmental change in sensitivity to exogenous H2O2, the 9-16-cell embryos being more resistant than zygotes and blastocysts and that H2O2 and its toxic effects can be attenuated by including pyruvate in the medium. 相似文献
1000.
UQBT: adaptable binary translation at low cost 总被引:1,自引:0,他引:1
Developments in the semiconductor industry have made possible smaller and faster processors for general-purpose computing, portable devices, multipurpose appliances, and system-on-chip designs. Binary translation offers a quick, inexpensive way to migrate software from one processor to another. Although binary-translation techniques are still in their infancy compared to their compiler counterparts, engineers have been using them for 15 years. Just as engineers build compilers partly on the basis of specifications, the authors are developing the University of Queensland Binary Translator (UQBT) on the basis of machine specifications and properties of machines and operating systems. This static binary-translation framework supports various processors, including complex-instruction-set computers (CISC), reduced-instruction-set computers (RISC), and stack-based machines. The authors describe the UQBT framework and discuss their observations while using it to instantiate six different translators across Sun Sparc, Intel Pentium, and Java virtual-machine architectures 相似文献