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排序方式: 共有602条查询结果,搜索用时 31 毫秒
21.
M. Berkan Sesen Michael D. Peake Rene Banares-Alcantara Donald Tse Timor Kadir Roz Stanley Fergus Gleeson Michael Brady 《Journal of the Royal Society Interface》2014,11(98)
Multidisciplinary team (MDT) meetings are becoming the model of care for cancer patients worldwide. While MDTs have improved the quality of cancer care, the meetings impose substantial time pressure on the members, who generally attend several such MDTs. We describe Lung Cancer Assistant (LCA), a clinical decision support (CDS) prototype designed to assist the experts in the treatment selection decisions in the lung cancer MDTs. A novel feature of LCA is its ability to provide rule-based and probabilistic decision support within a single platform. The guideline-based CDS is based on clinical guideline rules, while the probabilistic CDS is based on a Bayesian network trained on the English Lung Cancer Audit Database (LUCADA). We assess rule-based and probabilistic recommendations based on their concordances with the treatments recorded in LUCADA. Our results reveal that the guideline rule-based recommendations perform well in simulating the recorded treatments with exact and partial concordance rates of 0.57 and 0.79, respectively. On the other hand, the exact and partial concordance rates achieved with probabilistic results are relatively poorer with 0.27 and 0.76. However, probabilistic decision support fulfils a complementary role in providing accurate survival estimations. Compared to recorded treatments, both CDS approaches promote higher resection rates and multimodality treatments. 相似文献
22.
Kathryn Rounding Kimberly Tee Xiaomin Wu Cheng Guo Edward Tse 《Personal and Ubiquitous Computing》2013,17(8):1663-1666
Children are very different from adults—they have developing motor skills, limited reach, short attention spans, limited exposure to traditional user interfaces and social protocols. How do we evaluate user interfaces for children? In this paper, we present four evaluative techniques that we have successfully used with children. 相似文献
23.
Yung‐Tse Hung 《The International journal of environmental studies》2013,70(3-4):261-270
The batch shaking adsorption study was conducted to determine the potential of fly and volcanic ashes in removing organic pollutants from oxidation pond effluents. Factors affecting organic pollutant removals, such as concentrations and sizes of fly and volcanic ashes, initial pond effluent organic concentrations, washed and unwashed conditions of fly and volcanic ashes, were investigated. The TOC (total organic carbon) removal efficiency varied from 30 to 58 percent. The organic removal efficiency increased with increasing ash concentrations, with decreasing initial pond effluent organic concentrations and with decreasing sizes of ashes. 相似文献
24.
This paper has the objective of improving on the issue of forecasting new housing construction, and highlights differences between space demand and investment demand in housing markets. Further, it indicates how these differences will affect construction decisions. The first step is to identify the factors associated with estimating residential property prices in Hong Kong, based on a demand-supply adjustment process. Specifically, this study examines the role of population growth, transaction volume, inflation and interest rate in determining house prices. Second, based on these estimations, a methodology is developed to estimate the investment demand schedule and new construction of residential property. 相似文献
25.
Fei Xu Wei‐Jing Yu Da‐Wen Sun Xue‐Qin Xu Tse‐Chao Hua 《Journal of the science of food and agriculture》2008,88(14):2538-2542
BACKGROUND: In enzyme inhibition‐based biosensors for the detection of organophosphate and carbamate pesticides, the biological element is the immobilised esterase which is inhibited selectively by the pesticides. The free chicken liver esterase, which possesses comparable inhibition response to the pesticides as AChE, has been reported. However, the responses to the pesticides are different between the free and immobilised enzyme due to the diffusion limitation. Therefore, in this study four typical pesticides were selected to compare the ability of free and (ion exchange) immobilised chicken enzyme for pesticide detection and reasons for the difference were investigated. RESULTS: For dichlorvos and malathion at a concentration of 0.1 mg L?1, the inhibition of the immobilised enzyme was 26.98% and 48.72%, respectively, higher than that for the free enzyme, while the percentage inhibition of free and immobilised enzyme differed very little for trichlorfon at 0.1 mg L?1. In the meantime, carbaryl at a concentration of 2.5 mg L?1 showed a 17.72% inhibition for immobilised enzyme which was 13.64% higher than that for the free enzyme. The Michaelis constant of immobilised enzyme was lower than that of the free one and suitable pH values for the free and immobilised enzyme were 7.5 and 8.0, respectively. CONCLUSIONS: The sensitivity of chicken liver esterase to the pesticide inhibition could be improved by immobilisation. Smaller Km and a lower pH for the micro‐environment of immobilised enzyme should result in higher percentage inhibition compared with that of the free enzyme. Copyright © 2008 Society of Chemical Industry 相似文献
26.
Duchek Janet M.; Balota David A.; Tse Chi-Shing; Holtzman David M.; Fagan Anne M.; Goate Alison M. 《Canadian Metallurgical Quarterly》2009,23(6):746
This study explored differences in intraindividual variability in 3 attention tasks across a large sample of healthy older adults and individuals with very mild dementia of the Alzheimer’s type (DAT). Three groups of participants (healthy young adults, healthy older adults, very mild DAT) were administered 3 experimental measures of attentional selection and switching (Stroop, Simon, task switching). The results indicated that a measure of intraindividual variability, coefficient of variation (CoV; SD/M), increased across age and early stage DAT. The CoV in Stroop discriminated the performance of ε4 carriers from noncarriers in healthy older controls and the CoV in task switching was correlated with cerebrospinal fluid (CSF) biomarkers predictive of DAT. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
Recently the electronic structure and magnetism of the “111” type LiFeAs superconductor has been investigated by first principles
calculations based on the density functional theory. It is concluded that the system has a metallic striped anti-ferromagnetic
ground state with a very small magnetic moment. Moreover, the effect of electronic correlation effect is also found to be
weak. This finding is consistent with recent experiments and calculations on similar compounds. A strong covalent interaction
has been suggested as a reason for the weak electron correlation. In this paper, the Fe–As and Fe–Fe interactions are examined
from the analysis of the electronic localization function (ELF). Surprisingly, no strong evidence supporting Fe–As and Fe–Fe
covalent bonding is found. A more delocalized electron distribution is observed in the Fe layers. Therefore, the Fe 3d electrons
are not as localized in the oxides and therefore the electron correlation effect is small. This is a plausible explanation
for the apparent success of the local density approximation (LSDA) describing the weak magnetism in LiFeAs. 相似文献
28.
C. K. Tse Y. S. Lee W. C. So 《International Journal of Circuit Theory and Applications》1993,21(4):371-384
An approach to modelling DC-DC converter circuits based on graph theoretic concepts is discussed in this paper. the DC-DC converter circuits are treated as networks containing switches, with the magnitudes of their associated eigenvalues much smaller than the switching frequency. the procedure for modelling this class of networks essentially involves separating the original network into two N-port networks, one containing those branches responsible for all phenomena peculiar to the switching action and the other containing the remaining branches of the network. the two N-port networks thus formed lead to a systematic and convenient way of developing low-frequency circuit models for DC-DC converter circuits. 相似文献
29.
B Tse JM Balkovec CM Blazey MJ Hsu J Nielsen D Schmatz 《Canadian Metallurgical Quarterly》1998,8(16):2269-2272
Sordarin (1) was converted to 5 and 6, which showed potent antifungal activity against yeast. A series of C1-C9 alkyl side-chain derivatives was prepared, from which it was found that the optimal activity occurred with C5. A comparison of side chains with different unsaturation showed that the cis-alkene was the most active. This result suggested that the folding of the side chains might be crucial for the optimal activity. 相似文献
30.
The deterministic prediction of both transient and CW field coupling to large complex electrical systems poses such a formidable problem that other approaches to predicting the coupling may be useful The continuous wave coupling to a complicated electrical system is analyzed in terms of random small dipole interactions in the low-frequency limit (wavelengthsgg system components' sizes). Both random coupling to the incident wave and random interactions among the dipoles are considered. The variables being randomized are the incident direction and polarization, the sizes and orientations of the dipoles, the mutual coupling strengths, and the lumped load impedances. The resulting normalized current distributions are shown to be insensitive to the details of the model except at the extremely low and high percentiles. The magnetic dipole case is investigated in detail. Its resulting induced current distribution roughly resembles, but is not, a log-normal distribution with a standard deviation in the vicinity ofsim6 dB. This result provides insight into some recent measurements obtained for EMP transient field coupling to large systems. An important implication of the results is that for a variety of complicated systems, essentially consisting of many small elements that the coupling is dominated by low-frequency magnetic fields, the central parts of the induced current probability distributions are similar and nearly log-normal. However, conclusions based on the extrapolation of log-normality from measured values near the median to the extreme percentiles may be susceptible to sizeable errors. The electric dipole ease is presented very briefly here, only to the extent of its basic formulations. We refer interested readers to our original report for some basic results for this case and also for the effects caused by an elliptically polarized incident wave versus a linearly polarized one. 相似文献