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91.
Valerie L. Shalin 《Cognition, Technology & Work》2005,7(3):198-211
The requirements and issues associated with computational representations for planning extend beyond those apparent in real-time control, where a substantial, existing research literature informs designers. To assist in the identification of requirements for planning representations, this paper provides two resources: (1) a theoretical foundation drawn from computer science and (2) illustrations of representations and corresponding work practice for real-time control and planning for the US Shuttle program. Together, these resources illustrate the human role in the planning process, and the need for work practices and information that combine to assist human operators in interpreting a representation that is loosely coupled to the physical world while shared among and modified by multiple participants in the planning process.
相似文献
Valerie L. ShalinEmail: |
92.
93.
Miller Michael L.; Chiles John A.; Barnes Valerie E. 《Canadian Metallurgical Quarterly》1982,50(4):491
Contrasted 30 13–15 yr old delinquents who had attempted suicide with 120 delinquent controls. Multiple regression analyses showed that suicidal ideation, depression, gender, a tendency to act out, conflict with parents, childhood hyperactivity, and the interactions of gender with depression and with acting out accounted for 49% of the variance in suicide attempts. Females were found to attempt suicide 2? times as often as males. Females were also more likely to attempt suicide when depressed than were similarly depressed males. Male and female delinquents who engaged in a high level of acting out were equally likely to attempt suicide, but females who did not act out were more likely to attempt suicide than males who did not act out. Similarities between these adolescent attempters and adult suicide attempters described in the literature are discussed. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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95.
Kersten S. Rabe Dipl.‐Biochem. Mark Spengler Dr. Michael Erkelenz Dipl.‐Biotechnol. Joachim Müller Dipl.‐Chem. Valerie J. Gandubert Dr. Heiko Hayen Dr. Christof M. Niemeyer Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(4):751-757
The big screen : We have devised a high‐throughput screening method for organic peroxide‐dependent P450 reactivity by taking advantage of a previously undescribed activity of catalase, which was used as reporter enzyme. This two‐step assay, followed by liquid chromatography/mass spectrometry analyses, allowed the facile identification of several new substrates for bacterial P450 enzymes.
96.
Kanchan Taori Yanxia Liu Dr. Valerie J. Paul Dr. Hendrik Luesch Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(10):1634-1639
Combinatorial biosynthesis meets combinatorial pharmacology, cyanobacterial style : A new antimitotic natural product with features of both dolastatins 10 and 15 was isolated from the same Floridian Symploca sp. sample that produced the histone deacetylase inhibitor largazole. Both agents in combination are more effective in inhibiting cancer cell proliferation than either agent alone.
97.
Congli Wang George Bruening Valerie M. Williamson 《Journal of chemical ecology》2009,35(10):1242-1251
Root-knot nematodes (Meloidogyne spp.) are obligate endoparasites of a wide range of plant species. The infective stage is attracted strongly to and enters host roots at the zone of elongation, but the compounds responsible for this attraction have not been identified. We developed a simple assay to investigate nematode response to chemical gradients that uses Pluronic F-127, a synthetic block copolymer that, as a 23% aqueous solution, forms a liquid at low temperature and a gel at room temperature. Test chemicals are put into a modified pipette tip, or ‘chemical dispenser,’ and dispensers are inserted into the gel in which nematodes have been dispersed. Meloidogyne hapla is attracted to pH gradients formed by acetic acid and several other Brønsted acids and aggregates between pH 4.5 and 5.4. While this pH range was attractive to all tested root-knot nematode strains and species, the level of aggregation depended on the species/strain assessed. For actively growing roots, the pH at the root surface is most acidic at the zone of elongation. This observation is consistent with the idea that low pH is an attractant for nematodes. Root-knot nematodes have been reported to be attracted to carbon dioxide, but our experiments suggest that the observed attraction may be due to acidification of solutions by dissolved CO2 rather than to CO2 itself. These results suggest that Pluronic F-127 gel will be broadly applicable for examining responses of a range of organisms to chemical gradients or to each other. 相似文献
98.
Studholme C Drapaca C Iordanova B Cardenas V 《IEEE transactions on medical imaging》2006,25(5):626-639
This paper is motivated by the analysis of serial structural magnetic resonance imaging (MRI) data of the brain to map patterns of local tissue volume loss or gain over time, using registration-based deformation tensor morphometry. Specifically, we address the important confound of local tissue contrast changes which can be induced by neurodegenerative or neurodevelopmental processes. These not only modify apparent tissue volume, but also modify tissue integrity and its resulting MRI contrast parameters. In order to address this confound we derive an approach to the voxel-wise optimization of regional mutual information (RMI) and use this to drive a viscous fluid deformation model between images in a symmetric registration process. A quantitative evaluation of the method when compared to earlier approaches is included using both synthetic data and clinical imaging data. Results show a significant reduction in errors when tissue contrast changes locally between acquisitions. Finally, examples of applying the technique to map different patterns of atrophy rate in different neurodegenerative conditions is included. 相似文献
99.
Auffan M Decome L Rose J Orsiere T De Meo M Briois V Chaneac C Olivi L Berge-Lefranc JL Botta A Wiesner MR Bottero JY 《Environmental science & technology》2006,40(14):4367-4373
Although the current production of oxide nanoparticles may be modest, the wide range of proposed applications and forecasted growth in production has raised questions about the potential impact of these nanoparticles on the environment and human health. Iron oxide nanoparticles have been proposed for an increasing number of biomedical applications although in vitro toxicity depending on the particles coating has been evidenced. The aim of this study was to examine the potential in vitro cyto- and genotoxicity on human dermal fibroblasts of DMSA-coated maghemite nanoparticles (NmDMSA) as a function of well-defined physicochemical states. Well-stabilized NmDMSA produced weak cytotoxic and no genotoxic effects. This is attributed in part to the DMSA coating, which serves as a barrier for a direct contact between nano-oxide and fibroblasts, inhibiting a potential toxic effect. 相似文献
100.
Valerie M. K. Werner Roman Krumpholz Christoph Rehekampff Tim Scherzer Markus Eblenkamp 《Polymer Engineering and Science》2019,59(7):1315-1331
For bioprotective encapsulated Internet of Things (IoT) electronics for the medical market, especially for cost‐effective, single or multiple use, injection molding will be of major importance. The stresses from the production process pose special challenges for electronics. The aim of the study was the simulative and experimental characterization of the load spectrum from the injection molding process and its effects on electronics. General recommendations for the encapsulation of IoT electronics in polymer matrices were derived. A microcontroller‐controlled temperature sensor board and a suitable injection mold were developed. Eight circumferential NTC‐sensors measured the prevailing thermal load directly on the component during overmolding. A simulation model allowed statements on the loads to be made about individual components, validated in experimental tests. In addition to PP and PMMA, PSU with a melt temperature of 360°C was tested. The temperature influence of the melt could be described as a function of the component position. The loss of adhesion, shrinkage, distortion, cavities, and delamination were analyzed using micrograph analysis. Complete functionality of the electronics was ensured after encapsulation. Optimization strategies were developed for the design of both IoT electronics and the injection mold. Novel concepts such as interlayer or backfill vias could be derived for future research approaches. POLYM. ENG. SCI., 59:1315–1331 2019. © 2019 Society of Plastics Engineers 相似文献