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1.
OL Lopez RP Brenner JT Becker RF Ulrich F Boller ST DeKosky 《Canadian Metallurgical Quarterly》1997,48(6):1521-1525
We examined whether either psychotic features (e.g., delusions and hallucinations) or EEG abnormalities are associated with more rapid progression of Alzheimer's disease (AD). AD patients with psychosis have exhibited more EEG abnormalities than those without psychosis, and both abnormal EEG and psychosis have been noted to be predictors of functional and cognitive decline in AD. Ninety-five probable AD patients participating in a longitudinal study of dementia had an EEG and a semistructured psychiatric interview at baseline. Using EEG spectral analysis, we classified records as normal/abnormal based on the parasagittal mean frequency. Patients with abnormal EEGs were more functionally (e.g., Blessed Rating Scale for activities of daily living) and cognitively (e.g., Mini-Mental State) impaired than patients with normal EEG. AD patients with psychosis were only more functionally impaired than patients without psychosis. A two-factor analysis showed no interaction between abnormal EEG and psychosis. In addition, using a Cox proportional hazard model adjusted for age and education, the presence of an abnormal EEG or psychotic symptom at study entry was associated with higher risk of reaching severe cognitive and functional impairment during follow-up. Neither abnormal EEG nor the presence of psychosis predicted death. These results indicate that both abnormal EEG and psychosis are independent predictors of disease progression but not of physical survival. 相似文献
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Dr. Jana Buchwalter Prof. Dr. Walter Brenner Dr. Rüdiger Zarnekow 《WIRTSCHAFTSINFORMATIK》2002,44(4):345-353
Many companies and purchasing departments only possess a limited knowledge about the modelling of inter-company business processes for electronic procurement. In the past the discussion about electronic procurement was mostly focused on technical aspects. This article introduces a reference process model for procurement auctions. The process model is made up of a basic process, which describes a minimal process for procurement auctions, and a number of process alternatives, which allow for the adoption of the basic process to changing parameters and individual company requirements. 相似文献
5.
A novel generic design for waveguide grating routers is demonstrated in the InP-InGaAsP material system that reduces the chip size by 50%, while still maintaining relaxed processing tolerances. Experimental results confirm no degradation in device performance for the compact design when compared to conventional devices 相似文献
6.
Polarisation insensitive semiconductor optical amplifier withintegrated electroabsorption modulators
Koren U. Miller B.I. Young M.G. Chien M. Raybon G. Brenner T. Ben-Michael R. Dreyer K. Capik R.J. 《Electronics letters》1996,32(2):111-112
The authors demonstrate a 1.55 μm wavelength multiquantum well semiconductor optical amplifier, integrated with bulk layer electroabsorption modulators and passive waveguide beam expanders at the input and output ports. The device has a fibre to fibre gain of 9 dB, an extinction ratio of 15 dB per modulator, a spectral range >35 nm, and polarisation sensitivity <1 dB 相似文献
7.
M. K. Miller S. S. Brenner M. G. Burke 《Metallurgical and Materials Transactions A》1987,18(5):519-523
The addition of palladium to a 4130 steel reduces its sensitivity to stress corrosion cracking and to hydrogen-induced cracking.
The atom probe field-ion microscope has been used to study the microstructure and microchemistry of these palladium-modified
4130 steels with particular emphasis on the distribution of palladium between the various phases and internal interfaces.
The palladium was found to segregate to the ferrite-ferrite lath boundaries to form a mono-atomically thick adsorbate layer.
Palladium-manganese precipitates both at the lath boundaries and in the ferrite matrix were also detected. Most of the palladium
was found to remain in solution in the ferrite. 相似文献
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Perception and action are based on the same visual information: distinction between position and velocity. 总被引:2,自引:0,他引:2
Ss were presented with spiders running from left to right at various velocities over a structured background. Motion of the background influenced the perceived velocity of the spider: Motion of the background in the opposite direction than the spider increased the perceived velocity. The perceived position of the spider was not influenced by background motion. Ss were asked to hit the spiders as quickly as possible. Fast spiders were hit with a higher velocity than slow spiders. The same effect was found if the spiders only differed in apparent velocity, induced by motion of the background. The trajectory of the hit was not influenced by motion of the background. The authors concluded that although velocity is nothing but the change of position in time, velocity and position are processed independently. Furthermore, these two separately processed sources of information are used in both perception and action. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Diplodom patagonicus is a freshwater bivalve mollusk living in lakes of the patagonian Andes mountains in Argentina. Lipid composition and seasonal
changes in the mollusk were studied in the natural habitat. In addition to common nonpolar and polar lipids, small amounts
of alk-1-enyldiacylglycerol ethers and significant quantities of ceramide aminoethyl phosphonate were present. Total lipid
content changed during the year, primarily because of decreased triacylglycerols in winter. The fatty acid composition of
the lipids, remarkably different from that of marine bivalves, and even from other fresh water animals, was especially rich
in the ω6 fatty acids, linoleic and arachidonic (ca. 25%), and poor in the ω3 acids, 20∶5 and 22∶6. The ω6/ω3 acid ratio was
ca. 2, which is very high compared to marine bivalves. The fatty acid composition and the ω6/ω3 acid ratio were constant during
the whole year, suggesting a very stable diet, rich in vegetal detritus and poor in diatoms. The influence of environmental
temperature fluctuation with season on fatty acid composition also was negible. Modest proportions of 22∶2 nonmethylene-interrupted
(NMI) acids were detected and confirmed by mass spectrometry. It was shown that 20∶2 NMI acids were absent. 相似文献