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991.
M Gazarian P Tugwell M Boers C Bombardier P Brooks R Day V Strand G Wells 《Canadian Metallurgical Quarterly》1999,26(1):207-209
There has been increasing recognition in recent years that the measurement of drug related toxicities in rheumatology clinical trials has been sub-optimal. The OMERACT Drug Toxicity Working Party was established to address this issue. The first task of the working party was to identify a minimum set of attributes of drug related toxicity that would be important to patients, clinicians, investigators, and policymakers. The working party then developed consensus on a standard set of properties for instruments to measure these attributes. Existing instruments in the field of rheumatology were ascertained by literature review and by contact with experts in the field. Four instruments were ascertained and evaluated using the guidelines developed by the working party. This report outlines the progress and preliminary results of these activities. 相似文献
992.
RIADH AL‐TAHIRI SHARAF OMAR ABDULLAH REWASHDEH 《International Journal of Dairy Technology》2008,61(4):347-351
The occurrence of bacteria from the genus Listeria in raw sheep milk and traditional local cheese was studied in three regions of the Karak district of Jordan. Conventional plating methods for the detection of Listeria species were followed to determine the average and the percentage of the contaminated samples. The result shows that there were significant differences between the regions in the study concerning the average and the percentage of positive occurrences of Listeria species in raw sheep milk. The results also showed that mainly L. monocytogenes and, to a lesser degree, L. ivanovii and L. innocua were found in the milk samples, while the occurrence of L. monocytogenes in cheese samples was very low. 相似文献
993.
Wells Deborah L.; McDonald Claire L.; Ringland Janice E. 《Canadian Metallurgical Quarterly》2008,122(2):213
Color plays an important biological role in the lives of many animals, with some species exhibiting preferences for certain colors over others. This study explored the color preferences of two species of ape, which, like humans, possess trichromatic color vision. Six western lowland gorillas, and six chimpanzees, housed in Belfast Zoological Gardens, were exposed to three stimuli (cloths, boxes, sheets of acetate) in red, blue, and green. Six stimuli of the same nature, in each of the three colors, were provided to both species for 5 days per stimulus. The amount of interest that the animals showed toward each stimulus of each color was recorded for 1 hr. Results showed that the apes, both when analyzed as two separate groups, and when assessed collectively, showed significant color preferences, paying significantly less attention to the red-, than to the blue- or green-colored stimuli. The animals' interest in the blue- and green-colored stimuli did not differ significantly. Overall, the findings suggest that gorillas and chimpanzees, our closest living relatives, may harbor color preferences comparable to those of humans and other species. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Mauricio S. Featherman Joseph S. Valacich & John D. Wells 《Information Systems Journal》2006,16(2):107-134
Abstract. As companies race to digitize physical-based service processes repackaging them as online e-services, it becomes increasingly important to understand how consumers perceive the digitized e-service alternative. We theorize that consumers often perceive e-services as being artificial and non-authentic, and that consumers must perform this assessment when deciding whether new e-services are viable alternatives to traditional service methods. This research investigates whether consumer perceptions of artificiality increase perceptions of e-service risk, which has been shown to hamper consumer acceptance in a variety of online settings. An empirical study operationalized perceived artificiality (PA) within a controlled laboratory experiment that manipulated the risk of a specific e-service class (e-payments). For a specific e-service brand, PA is reduced when the web interface is viewed as easy to use; alternatively, PA is increased when consumers have relatively high risk perceptions about the overall e-service class. Furthermore, consumers who were rated as information technology innovators had lower overall artificiality perceptions, however, exposure to negatively framed e-service efficacy information removed this artificiality reducing effect. The theoretical linkages between PA and perceived risk, and the two antecedents – ease of use and e-service class risk – were confirmed by survey results. The implications of these results for future research as well as the design and marketing of e-services are examined. 相似文献
995.
Police crash reports were obtained for pedestrian-motor vehicle crashes in Washington, DC (N = 852) and Baltimore (N = 1234) for the year 1998. Reports were coded using procedures developed and applied in these two cities during the 1970s, including the determination of pedestrian crash type, primary precipitating factor, and culpability. Results indicated substantial differences between crash patterns observed during the 1970s and those observed during 1998. Midblock dart-dash crashes, which typically involve a precipitating factor or critical error by a child pedestrian, decreased (from 37% to 15% in Washington). Across all crashes in both cities, the number of drivers who made a critical error leading to the crash was nearly equivalent to the number of pedestrians who made a critical error. Overall, pedestrians were slightly more likely to be judged culpable (50% vs. 39%). Turning vehicle crashes, which typically involve a driver's failure to grant a pedestrian the right of way at a signalized intersection, increased (from 9% to 25% in Washington). Countermeasures to reduce the number of pedestrians hit by turning vehicles are discussed. 相似文献
996.
A cylindrical geometry ion trap is used to record mass spectra in the mass-selective instability mode. The geometry of the cylindrical ion trap has been optimized to maximize the quadrupole field component relative to the higher-order field content through field calculations using the Poisson/Superfish code and through experimental variation of the electrode structure. The results correspond well with predictions of the calculations. The trap has been used to record mass spectra with better than unit mass resolution, high sensitivity, and a mass/charge range of ~600 Th. Multistage (MS(3)) experiments have been performed, and the Mathieu stability region has been experimentally mapped. The performance of this device compares satisfactorily with that of the hyperbolic ion trap. 相似文献
997.
The signs and symptoms of vasculitis are not specific, and tests for confirming the diagnosis can be misleading. Thus, when considering a diagnosis of vasculitis, physicians need to keep an open mind. With a case vignette, the author illustrates some of the difficulties in diagnosing "vasculitis." 相似文献
998.
AL Barck 《Canadian Metallurgical Quarterly》1998,117(8):461-463
In a previous study the "performance variability" of 15 different assessment systems after knee replacement was analysed. The notion that different knee evaluation systems measure different underlying factors was suggested. Three systems that seemed to have different underlying factors were selected, and a factor analysis was carried out to reduce the number of items in each group. The number of items could be reduced by 70%-82% with a minor loss of discriminating capacity. All instruments could be separated into items of pain, strength, mobility or stability. Pain measured on a visual analogue scale and self-selected walking speed were recommended for longitudinal monitoring of the treatment effect after knee replacement. 相似文献
999.
Venkat Subramanian Sven Achenbach David Klymyshyn Garth Wells Wade Dolton Vinay Nagarkal Brian Yates Curtis Mullin Martin Augustin 《Microsystem Technologies》2010,16(8-9):1547-1551
SyLMAND, the Synchrotron Laboratory for Micro and Nano Devices at the Canadian Light Source, consists of a dedicated X-ray lithography beamline on a bend magnet port, and process support laboratories in a cleanroom environment. The beamline comprises a double mirror system with flat, chromium-coated silicon mirrors operated at varying grazing angles of incidence for spectral adjustment by high energy cut-off. We present in this paper, the in situ diagnostic components inside the vacuum vessel upstream and downstream of the mirrors that allow for monitoring the incident beam and the reflected beam after first, second, and both mirrors. Four fly wire systems are used for beam position monitoring and intensity measurements. Additionally, four detector plates mounted on and moving with the mirror bodies are used to determine the position of the mirror surfaces with respect to the beam. First experimental results verify the capabilities of the system by showing good agreement between measured and calculated data. 相似文献
1000.
Object Detection and Localization by Dynamic Template Warping 总被引:1,自引:0,他引:1
Ratan Aparna Lakshmi Grimson W. Eric L. Wells William M. 《International Journal of Computer Vision》2000,36(2):131-147
A simple method is presented for detecting, localizing and recognizing instances of classes of objects, while accommodating a wide variation in an object's pose. The method utilizes a small two-dimensional template that is warped into an image, and converts localization to a one-dimensional sub-problem, with the search for a match between image and template executed by dynamic programming. For roughly cylindrical objects (like heads), the method recovers three of the six degrees of freedom of motion (2 translation, 1 rotation), and accommodates two more degrees of freedom in the search process (1 rotation, 1 translation). Experiments demonstrate that the method provides an efficient search strategy that outperforms normalized correlation. This is demonstrated in the example domain of face detection and localization, and can extended to more general detection tasks. An additional technique recovers rough object pose from the match results, and is used in a two stage recognition experiment in conjunction with maximization of mutual information. 相似文献