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11.
Blascovich Jim; Brennan Kelly; Tomaka Joe; Kelsey Robert M.; Hughes Pamela; Coad Mary Lou; Adlin Richard 《Canadian Metallurgical Quarterly》1992,63(1):164
Investigated in 3 experiments the relationships between affect intensity and basal, evoked, and perceived cardiac arousal. Affect intensity was assessed using R. J. Larsen and E. Diener's (1987) Affect Intensity Measure (AIM). Cardiac arousal was evoked with exercise in the 1st study and with mental arithmetic in the 2nd and 3rd. Perceived cardiac arousal was measured under optimal conditions using a standard heartbeat discrimination procedure. Women as a group scored higher on the AIM. Affect intensity was unrelated to basal or evoked cardiac arousal and was negatively related to perceived cardiac arousal in all 3 studies. Data suggest that affect intensity, although unrelated to actual physiological arousal, is negatively related to the accuracy with which individuals perceive their own arousal. Results are discussed within the context of an expanded arousal-regulation model (J. Blascovich, 1990). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
The paper describes a reduced forward operator for solving electromagnetic scattering problems using a volume integral equation in conjunction with a conjugate gradient fast Fourier transform scheme. The reduction is obtained by decoupling of the interaction between the locations in the spatial computational domain at which there is non-zero contrast and those positions at which there is zero contrast. The decoupling is achieved by multiplication of the kernel by a diagonal matrix whose entries reflect the presence or absence of contrast at the associated point. Analysis supported by numerical experiments shows that the conjugate gradient algorithm applied to the reduced system converges more rapidly than when it is applied to the original system 相似文献
13.
The storing of recorded bits in a perpendicular orientation holds great promise for high linear density recording systems. However, the most common embodiment of perpendicular recording (the probe head/double layer media) has several unresolved issues complicating its integration into commercial disk drives. The major issues include media relaxation, head induced media erasure, resolution limitations due to head-to-underlayer spacing constraints, and extreme sensitivity to stray magnetics fields, which are complex and highly interrelated. It is concluded that the realization of perpendicular recording in commercial disk drives will require new transducer and media designs that solve these problems 相似文献
14.
GY Lauwers RA Erlandson ES Casper MF Brennan JM Woodruff 《Canadian Metallurgical Quarterly》1993,17(9):887-897
The gastrointestinal autonomic nerve tumor (GAN tumor) is an uncommon stromal tumor of the intestinal tract and retroperitoneum first described by Herrera and associates in 1984. Distinction of GAN tumors from other gastrointestinal stromal tumors is based on electron microscopic findings. Thus far there have been 12 reported cases. We present an additional 12 GAN tumors, identified by us during 4 years. There were seven male and five female patients and they ranged in age from 10 to 85 years (mean: 58 years). Sites of the tumors were stomach (three), jejunum (two), ileum (four), mesentery (one), and retroperitoneum (two). Eight of the tumors measured > 10 cm in greatest dimension. Usually well circumscribed, the neoplasms were tan to light pink, sometimes hemorrhagic, and soft. There was a variety of histologic patterns including fascicles, palisades, and whorls. Mitotic activity varied from 0 to 23 mitosis per 10 high-power fields (HPF). Using a panel of 10 immunohistochemical stains, only vimentin was consistently positive. There was neuron-specific enolase reactivity in six and S-100 protein reactivity in two cases. All muscle markers were negative. Ultrastructural studies showed neuron-like cells with long axonic cytoplasmic processes ending in bulbous synapse-like structures containing dense-core neurosecretory granules and clear vesicles. Basement membrane was absent. These features are reminiscent of ganglia of the intestinal autonomic nervous system. The patients were followed for 5-125 months (mean of 26 months). Tumor recurred or metastasized to the liver in seven patients (58%) and four patients died with tumor. There were correlations between tumor size (> 10 cm), mitotic count (at least five per 10 HPF), and aggressive behavior. 相似文献
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Two techniques for modelling intermodulation-borne spurious components in fractional-N frequency synthesisers are described. The first techniques establishes the potential frequencies of these components, while the second considers a more comprehensive model to predict their distribution in a realistic system as a result of one particular intermodulation mechanism. Good agreement is found and it is apparent that intermodulation is likely to be a major cause of such spurious components. 相似文献
17.
Residential consumers remain reluctant to choose new electricity suppliers. Even the most successful jurisdictions, four US states and other countries, have had to adopt extensive consumer education procedures that serve largely to confirm that choosing electricity suppliers is daunting. Electricity is not unique in this respect; numerous studies find that consumers are generally reluctant to switch brands, even when they are well-informed about product characteristics. If consumers prefer not to choose, opening regulated markets can reduce welfare, even for some consumers who do switch, as the incumbent can exploit this preference by raising price above the formerly regulated level. Policies to open markets might be successful even if limited to industrial and commercial customers, with residential prices based on those in nominally competitive wholesale markets. 相似文献
18.
Fractional-sample delay in discrete-time systems is often provided by special FIR filters which are asymmetric about mid-sequence. Here we preserve the appeal of sine-sequence fractional delayers (simplicity and single-parameter delay tuning) by devising a two-term raised-cosine window which delivers fractional-delay filters comparable to the best obtainable by highly regarded optimisation approaches 相似文献
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20.
Caroline K. Brennan Marya Y. Ornelas Zi W. Yao Prof. Dr. Jennifer A. Prescher 《Chembiochem : a European journal of chemical biology》2021,22(16):2650-2654
Bioluminescent tools have been used for decades to image processes in complex tissues and preclinical models. However, few distinct probes are available to probe multicellular interactions. We and others are addressing this limitation by engineering new luciferases that can selectively process synthetic luciferin analogues. In this work, we explored naphthylamino luciferins as orthogonal bioluminescent probes. Three analogues were prepared using an optimized synthetic route. The luciferins were found to be robust emitters with native luciferase in vitro and in cellulo. We further screened the analogues against libraries of luciferase mutants to identify unique enzyme-substrate pairs. The new probes can be used in conjunction with existing bioluminescent tools for multi-component imaging. 相似文献