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31.
OBJECTIVE: Studies of sex differences in neuropsychological performance in schizophrenia report inconsistent results, due in part to methodological artifacts. The study presented here was specifically designed to examine sex differences in neuropsychological performance. It was hypothesized that schizophrenic women would exhibit fewer neuropsychological deficits than schizophrenic men and that their performance would be more similar to that of normal women than schizophrenic men's performance would be to that of normal men. METHOD: Thirty-one outpatients with DSM-III-R-defined schizophrenia were systematically sampled from an extensive service network serving a large urban catchment area for seriously mentally ill persons. Twenty-seven normal comparison subjects were matched within sex on the basis of age, parental socioeconomic status, ethnicity, and handedness. An extensive neuropsychological test battery was administered, and multivariate analysis of variance was used to test for the effects of sex and group and sex-by-group interactions. RESULTS: Male patients were significantly impaired across all functions in comparison with normal male subjects and on tests of attention, verbal memory, and executive functions in comparison with female patients. Female patients performed significantly worse than female normal comparison subjects only on tests of attention, executive functions, visual memory, and motor functions. CONCLUSIONS: The findings suggest that women with schizophrenia may be less vulnerable to particular cognitive deficits, especially those involving verbal processing, than schizophrenic men.  相似文献   
32.
Magnetic optical sensor particles with multifunctional cores and shells are synthesized via a facile nanoprecipitation method and the subsequent modification of the particle shell. The hydrophobic particle core includes optical oxygen indicators, a light harvesting system, photosensitizers, and magnetic nanoparticles. Further functionalities are introduced by modifying the shell with enzymes, antibodies, multiple layers of polyelectrolytes, stimuli‐responsive polymers, and luminescent indicator dyes. The hydrodynamic diameter is tunable by varying different precipitation parameters.  相似文献   
33.
My method is better!   总被引:1,自引:1,他引:0  
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34.
35.
In the above-named work (see ibid., vol.38, p.51-7, April 1989), S. Lafiti and A. El-Amawy apply, in a straightforward manner, the method developed by A.D. Singh (1985) to calculate lower bounds for the yield of nonplanar interstitial redundancy topologies of processor arrays with spare processors. In their introduction, they claim that the models suggested by I. Koren and D.K. Pradhan (1987) are highly theoretical since the number of states in the Markov model might be very large and the determination of the transition rates might be intractable. They add that applying some empirical rules, as suggested by Koren and Pradhan (1987), can lead to unrealistic results and may require a large number of computations. They also claim that the model of Koren and Pradhan does not suggest an algorithm to replace faulty elements. They conclude that a simpler model, like the one proposed by Singh, is needed for calculating the yield of fault-tolerant processor arrays. In the present comment, Koren and Pradhan respond to the above comments and attempt to clarify the differences between their yield analysis and that of Singh  相似文献   
36.
The local voltage fluctuations in the supply and ground grids triggered by on-die logic cell switching in VLSI devices have been experimentally studied. The results show that these fluctuations have a resonant-like form i.e., the on-die power grid should be described as an RLC circuit. The studies reveal that the active element (i.e., CMOS logic cell) affects the frequency properties of power supply and ground grids during its switching (as opposed to before or after switching). It is demonstrated that the frequency properties of the both grids are inter-related via the interconnecting active elements.  相似文献   
37.
Conclusions An analysis showed that the water intakes for selective withdrawal of water from a reservoir for water-supply purposes known from the scientific and technical literature cannot be used effectively for withdrawing a large quantity of water for hydrostation turbines, and the known intakes for selective withdrawal of a large quantity of water have substantial shortcomings and are in need of further design improvement. Simultaneously with this, the conclusions of the 1993 Divnogorsk conference that at present “it is impossible to freeze the Yenisei River within the Krasnoyarsk city limits” for a number of reasons is confirmed. However, under more favorable conditions than the Krasnoyarsk hydrostation, the selective withdrawal of water from a deepwater intake for hydrostation turbines, despite the high additional expenditures, can be justified and necessary. The proposed design of a floating intake of an electric power station has a number of advantages compared with the known floating intakes. In this case it recommended to direct the water that is withdrawn from the surface layer of the reservoir and passed only through one or two turbines to save expenditures to the bank part of the river, which promotes in the lower pool the formation of ice near the river banks and in its branches in the winter and their “warming” in the summer. Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 9, pp. 46–49, September, 1997.  相似文献   
38.

Background  

Short-chain fructo-oligosaccharides (scFOS) are increasingly used in human diet for their prebiotic properties. We aimed at investigating the effects of scFOS ingestion on the colonic microflora and oro-fecal transit time in elderly healthy humans.  相似文献   
39.
The balanced operation of a multiple-quantum-well balanced heterodyne receiver photonic integrated circuit (PIC) is described. Using only SMA-connected 50 Ω commercial electronics, a free-space beam sensitivity of -42.3 dBm at 108 Mb/s and -39.7 dBm at 200 Mb/s for NRZ FSK (frequency-shift keying) reception has been achieved. This represents a 14 dB improvement over any previous heterodyne receiver PIC sensitivity. In addition to providing the multichannel benefits of heterodyne reception, this is also the highest sensitivity yet reported for any OEIC (optoelectronic integrated circuit) receiver  相似文献   
40.
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