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51.
BCI Meeting 2005--workshop on signals and recording methods.   总被引:4,自引:0,他引:4  
This paper describes the highlights of presentations and discussions during the Third International BCI Meeting in a workshop that evaluated potential brain-computer interface (BCI) signals and currently available recording methods. It defined the main potential user populations and their needs, addressed the relative advantages and disadvantages of noninvasive and implanted (i.e., invasive) methodologies, considered ethical issues, and focused on the challenges involved in translating BCI systems from the laboratory to widespread clinical use. The workshop stressed the critical importance of developing useful applications that establish the practical value of BCI technology.  相似文献   
52.
A mathematical model was developed to estimate the efficacy of coagulation–flocculation treatment for removing neutral hydrophobic organic chemicals from raw drinking water. The model assumed that the only significant removal mechanism was the destabilization and settling of organic matter containing sorbed anthropogenic organic compounds. The model was validated with standard jar tests using compounds with a range of hydrophobicities (log?Kow = 1.89?to?5.48), including contaminant candidate list chemicals, pesticides, pharmaceuticals, and endocrine disrupting chemicals. Final concentrations of test compounds after coagulation and flocculation were in good agreement with model estimations for synthetic waters composed of Aldrich (Milwaukee, WI) humic acid solutions. The final compound concentrations in coagulated natural waters from two drinking water reservoirs were about 80% lower than those estimated with the model. Overestimations of treated water concentrations by the model were attributed to an increase in sorption by natural organic matter when coiled in aluminum hydroxide flocs, compared to sorption to dispersed natural organic matter in untreated water.  相似文献   
53.
Early Head Start, a federal program begun in 1995 for low-income pregnant women and families with infants and toddlers, was evaluated through a randomized trial of 3,001 families in 17 programs. Interviews with primary caregivers, child assessments, and observations of parent-child interactions were completed when children were 3 years old. Caregivers were diverse in race-ethnicity, language, and other characteristics. Regression-adjusted impact analyses showed that 3-year-old program children performed better than did control children in cognitive and language development, displayed higher emotional engagement of the parent and sustained attention with play objects, and were lower in aggressive behavior. Compared with controls, Early Head Start parents were more emotionally supportive, provided more language and learning stimulation, read to their children more, and spanked less. The strongest and most numerous impacts were for programs that offered a mix of home-visiting and center-based services and that fully implemented the performance standards early. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
Although it is widely accepted that control mechanisms are necessary for human behavior to be adapted, very little is known about how such mechanisms are recruited. A suggestion to fill the gap was put forward by M. M. Botvinick, T. S. Braver, C. S. Carter, D. M. Barch, and J. D. Cohen (2001), who proposed the conflict-loop theory. This theory has been successful in accounting for the reduction of compatibility effects after an incompatible trial: The level of conflict being, on average, higher during an incompatible trial, more control occurs after such a trial. The authors have tested this prediction by sorting the trials on the basis of amount of conflict (quantified by the electromyographic activity) they presented. A reduction of the compatibility effect was observed after incompatible trials, but it was independent of the level of conflict on previous trials, suggesting that the conflict does not trigger changes in executive control. Consequences for the conflict monitoring model are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
55.
We present scanning tunnelling microscope (STM) images of untreated tobacco mosaic virus (TMV) deposited on thermally evaporated and on sputter-coated palladium/gold 40:60 (Pd/Au) substrates, and imaged under ordinary atmospheric conditions. The TMV imaged on both evaporated and sputter-coated substrates was consistently several times wider than the known diameter of the virus. TMV on evaporated Pd/Au became overcoated with Pd/Au material during sample preparation and appeared elevated in STM images, whereas TMV on sputter-coated Pd/Au appeared as depressions. When naked TMV were intentionally overcoated with Pd/Au, the STM images were found to be similar to those for TMV on evaporated Pd/Au.  相似文献   
56.
In this paper, high resolution, remotely-sensed data are investigated as a source of management information for moorland vegetation communities on a hypothetical farm in a marginal farming area of Scotland. A hybrid technique for vegetation mapping is adopted. This involves unsupervised machine classification of spectral variation in digitally enhanced air photographs and satellite imagery, together with visual interpretation of the imagery in both the laboratory and the field. This technique enables relative estimates of annual gross biomass production, for a range of vegetation types, to be obtained. The data are integrated into a simple heather moorland management model (HMMM), to produce potential sheep-stocking capacities under a range of management scenarios, the possible financial implications of these scenarios are also assessed.  相似文献   
57.

Vibration analysis of square and circular piezoelectric micro ultrasonic transducers (pMUTs) in the 100 kHz range as a function of experimental tools are reported. Analytical and 3D finite element method analysis using Comsol software has been performed to model static, modal and vibration behavior of these membranes. Comparison with standard impedancemeter measurement is shown to assess the performance of Laser Doppler Vibrometry system. Mechanical and electrical characterization and comparison with a model results are presented and discussed. The measured resonances frequencies of membrane can be weak and superimposed on important parasitic signal, which may mask the desired mechanical resonance signal. Our results revealed the real roles of the simulations and the combination of the experimental tools to get measurement accuracy. Subsequently, this piezoelectric micro-transducer was successfully tested as a sounder in air. These investigations offer guidance for the pMUTs design and associated electronic circuit but might at the same time be instructive and beneficial to further sensor applications.

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Single use technology (SUT) is in widespread use throughout the biopharmaceutical industry where it is replacing traditional stainless steel plant particularly for the manufacture of small volume, high value products. The key drivers for SUT uptake include reduction of regulatory risk, lower capital and energy costs and increased facility flexibility. Disposable technology is now well established for cell culture, liquid handling and storage but its application to some downstream operations is proving more intractable. Single‐use chromatography resins are generally uneconomic at process scale and there are limitations on large‐scale tangential flow filtration capacities. The development of disposable sensor technology is lagging behind that of bioreactors and capacities for microbial culture are presently limited to 2000 litres. Concerns regarding compatibility of equipment from different suppliers and extractable and leachable testing are being addressed but continue to influence uptake of SUT by traditional manufacturers. Complete ‘plug and play’ disposable process trains, however, are becoming increasingly available and are being embraced by Contract Manufacturing Organisations (CMOs) with multiproduct facilities. © 2013 Society of Chemical Industry  相似文献   
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