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71.
We introduce a new class of substrates (compounds I – III ) for leukocyte esterase (LE) that react with LE yielding anodic current in direct proportion to LE activity. The kinetic constants Km and kcat for the enzymatic reactions were determined by amperometry at a glassy carbon electrode. The binding affinity of I – III for LE was two orders of magnitude better than that of existing optical LE substrates. The specificity constant kcat/Km was equal to 2.7, 3.8, and 5.8×105 m ?1 s?1 for compounds containing the pyridine ( I ), methoxypyridine ( II ), and (methoxycarbonyl)pyridine ( III ), respectively, thus showing an increase in catalytic efficiency in this order. Compound III had the lowest octanol/water partition coefficient (log p=0.33) along with the highest topological surface area (tPSA=222 Å2) and the best aqueous solubility (4.0 mg mL?1). The average enzymatic activity of LE released from a single leukocyte was equal to 4.5 nU when measured with compound III .  相似文献   
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73.
Asynchronous Transfer Mode (ATM) has been under development in laboratories since the early 1980s and although considered as a new technology is basically a technology that is coming of age. The fit between the capability's deliverable by this technology and the needs of data networks today has prompted this coming of age. Unlike some technologies in the past, ATM is truly a response to the data networking needs of today and the future. It is this fit between customer requirements and the capabilities of ATM that assures the future of this technology.  相似文献   
74.
Independent components of magnetoencephalography: localization   总被引:5,自引:0,他引:5  
We applied second-order blind identification (SOBI), an independent component analysis method, to MEG data collected during cognitive tasks. We explored SOBI's ability to help isolate underlying neuronal sources with relatively poor signal-to-noise ratios, allowing their identification and localization. We compare localization of the SOBI-separated components to localization from unprocessed sensor signals, using an equivalent current dipole modeling method. For visual and somatosensory modalities, SOBI preprocessing resulted in components that can be localized to physiologically and anatomically meaningful locations. Furthermore, this preprocessing allowed the detection of neuronal source activations that were otherwise undetectable. This increased probability of neuronal source detection and localization can be particularly beneficial for MEG studies of higher-level cognitive functions, which often have greater signal variability and degraded signal-to-noise ratios than sensory activation tasks.  相似文献   
75.
Operating rooms (OR) are where medical teams work to improve the health of a patient. However, because of the complexity of the procedures, errors and unsafe situations are likely to occur. These complications can lead to harm to the patient or medical professionals. Human factors and ergonomic professionals have been working to improve these unsafe conditions in the OR for over a century. However, with advances in technology, increased surgical complexity, as well as an increase in medical team members in the OR, there are still numerous improvements yet to be accomplished. Minimally invasive surgeries require an even more advanced approach to prevent errors due to technology, fatigue, and miscommunication. Human factors and ergonomic techniques provide the ability to greatly improve conditions for patients and surgeons alike. It is imperative that human factors and ergonomics continue to grow and facilitate technological advancements in healthcare. © 2012 Wiley Periodicals, Inc.  相似文献   
76.
Immersion in virtual environments can cause simulator sickness (SS). Further, head and neck movement in interactive virtual reality (VR) assessment and training stimulates the vestibular and cervical afferent systems that can cause dizziness in subjects with neck pain and vestibular pathology. This cross-sectional, observational, study investigated SS and factors that may influence this between 20 neck pain, 14 vestibular pathology and 20 asymptomatic control subjects. Pre-VR questionnaires included a visual symptom scale and dizziness intensity. SS measures included the simulator sickness visual analogue scale and the simulator sickness questionnaire. Significantly greater incidence of any SS and higher values were found in the vestibular and neck pain groups compared to the control group in selected SS measures. No significant differences were found when comparing SS measures between the vestibular and neck pain groups. Significant mild-to-moderate correlations for the entire population were found between both SS measures to pre-VR visual symptoms and dizziness intensity. SS levels in neck pain and vestibular populations are comparable and higher than asymptomatic individuals. Dizziness and visual disturbances may be associated with an increase in severity of SS in these clinical populations.  相似文献   
77.
Software design is an area where it is most important to elicit an accurate and complete set of requirements. Determining the users requirements and their qualitative satisfaction with a developing product are two major problems which arise, often due to the different backgrounds and perspectives of the different stakeholders, including the software engineer, the domain expert and the end-user. Involving users throughout the design and development process is an essential part of any project. Computer-based interviewing has been found to be a valuable tool in eliciting information, which can also enhance interpersonal communication afterwards. This paper discusses the development of a computer interviewing tool to facilitate the gathering of user requirements and conducting user evaluations.  相似文献   
78.
Is current research on computing by older adults simply looking at a short-term problem? Or will the technology problems that plague the current generation also be problematic for today’s tech-savvy younger generations when they become “old”? This paper considers age-related and experience-related issues that affect ability to use new technology. Without more consideration of the skills of older users, it is likely that applications and devices 20 years from now will have changed such that this “older” generation finds themselves confronting an array of technologies that they little understand and find generally inaccessible. Recent evidence suggests that older adults bring specific strengths to Web browsing. A fuller investigation of these strengths and how to design to optimize for strengths of older users has the potential to address the need for usable technology for this increasingly important demographic.  相似文献   
79.
What unique assessment issues do evaluators face when conducting mental retardation evaluations in capital cases? This article describes 4 assessment issues and reports how 20 evaluators in 1 state have approached them: (a) What methods are appropriate for evaluating adaptive functioning in this context? (b) Should information about criminal behavior be used as evidence of adaptive functioning? (c) Should correctional officers serve as informants regarding adaptive behavior? and (d) How should the Flynn effect influence the interpretation of intelligence test scores? Implications for practice are that practitioners should expect to be asked about the relation between criminal behavior and adaptive functioning, must think carefully about the validity of tests of adaptive functioning for inmates, and must be knowledgeable about the current state of Flynn effect research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
In October 2005, the IBM Human Ability and Accessibility Center and T.J. Watson Research Center hosted a symposium on “cognitive and learning difficulties and how they affect access to IT systems”. The central premise of the symposium was the recognition that cognitive and learning difficulties have a profound impact on a person’s ability to interact with information technology (IT) systems, but that little support is currently being offered by those systems. By bringing together internationally renowned experts from a variety of different, but complementary, research fields, the symposium aimed to provide a complete overview of the issues related to this topic. This paper summarises the discussions and findings of the symposium.  相似文献   
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