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1.
Nuclear magnetism in the second layer of 3He films on graphite has been studied as a function of density in the zero-field limit at temperatures down to 300 µK. Total surface coverages in this study ranged from 20 atoms/nm2 (the lowest coverage at which the effective exchange parameter turns ferromagnetic) through the two-phase region (ending at about 24 atoms/nm2) and into the single-phase imcommensurate solid region up to 31.2 atoms/nm2. The surface layers were studied using both pulsed and cw NMR measured with our SQUID NMR system in magnetic fields of 500 µT and lower. As the surface density continues to increase in the single-phase region, the exchange constant decreases consistently with a picture of steric hindrance impeding ferromagnetic exchange. Several different observational features scale with this inferred exchange: low-field magnetization, NMR frequency shift, and the temperature of onset of significant magnetization.  相似文献   
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This paper presents a mechanism which infers a user's plans from his/her utterances by directing the inference process towards the more likely interpretations of a speaker's statements among many possible interpretations. Our mechanism uses Bayesian theory of probability to assess the likelihood of an interpretation, and it complements this assessment by taking into consideration two aspects of an interpretation: its coherence and its information content. The coherence of an interpretation is determined by the relationships between the different statements in the discourse. The information content of an interpretation is a measure of how well defined the interpretation is in terms of the actions to be performed on the basis of this interpretation. This measure is used to guide the inference process towards interpretations with higher information content. The information content of an interpretation depends on the specificity and the certainty of the inferences in it, where the certainty of an inference depends on the knowledge on which the inference is based. Our mechanism has been developed for use in task-oriented consultation systems. The particular domain that we have chosen for exploration is that of travel booking.  相似文献   
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Based on a contemporary cognitive-psychoanalytic theory (control-mastery theory; J. Weiss, H. Sampson, & Mount Zion Psychotherapy Research Group, 1986), this study proposed that college students have plans for college that consist of conscious and unconscious goals and obstructions to be overcome in meeting those goals. The construct of unconscious guilt was used to mediate the dual goals of autonomy and attachment. The idiographic plan-formulation method was adapted to derive plans for 12 sophomore women. Acceptable interjudge reliabilities and criterion validity were demonstrated, and several themes in the goals and obstructions were illustrated. Students worried more about mothers than about fathers, particularly when they perceived the mother as weak or needy. The potential of the method for generating inferences about unconscious process for normative development is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Interfacial microstructures in βP-Si3N4( w )-Si-Al-Y-O-N-glass systems were investigated by systematically varying the nitrogen content and the Al:Y ratio of the glass matrix. High-resolution and analytical transmission electron microscopy (HREM and AEM) studies revealed that the interfacial microstructure is a function of the glass composition. No interfacial phases were formed in glasses with low Al:Y ratios and in glasses with high Al:Y ratios and low nitrogen content, whereas epitaxial growth of an interfacial layer (100–200 μm thick) on the βP-Si3N4( w ) occurred in a glass matrix with high Al:Y ratio and high nitrogen content. The interfacial layer was identified to be a β'-SiAION phase. Interfaces containing the SiAION layer exhibited high debonding energy compared to Si3N4( w )–glass interfaces. HREM studies indicated that the lattice-mismatch strain in the SiAION layer was relieved by dislocation formation at the SiAION–Si3N4( w ) interface. The difference in interfacial debonding energy was, hence, attributed to the local atomic structure and bonding between the glass-β-Si3N4 and the glass–β'-SiAION phases. This observation was clear evidence of the strong influence of glass chemistry on the interfacial debonding behavior by altering the interfacial microstructure.  相似文献   
6.
Two cases of fibromatosis of the breast, characterized by a proliferation of spindle cells containing intracytoplasmic, spherical, eosinophilic inclusion bodies, are reported. The light and electron microscopic features, as well as the immunohistochemical features, are indistinguishable from those found in infantile digital fibromatosis. The proliferating spindle cells are characterized as myofibroblasts, whereas the inclusion bodies show an immunohistochemically nonreactive, hollow-like pattern with peripheral reactivity for actin filaments. This lesion, observed for the first time in the breast, expands the number of extradigital inclusion body fibromatoses.  相似文献   
7.
Focused ion beam (FIB) and nano-probing were applied for failure analysis of three-dimensional stacked circuits with copper through-silicon-vias between the stacked chips. The failure analysis was done after high temperature storage and thermal cycling tests. Passive voltage contrast in FIB allowed to pinpoint the open sites. FIB cross-sections showed the presence of opens at the bottom of the copper vias. The failure cause was suspected to be an interlayer particle, which was confirmed by optical profilometry. Nano-probing was used on another sample to pinpoint the failure location through the measurement of the local resistance within the daisy chains. The failure was traced out to be related with surface contamination.  相似文献   
8.
It has previously been shown that the Copenhagen (COP) rat contains several genetic loci that contribute to its mammary tumor-resistant phenotype after 7,12-dimethylbenz(a)anthracene (DMBA) administration. One of these loci, mammary carcinoma susceptibility 1 (Mcs1), is located on the centromeric end of chromosome 2 and appears to act in a semidominant fashion. To confirm the existence and independent action of this locus and also aid in the identification of the physical location of the Mcs1 gene, congenic lines were generated by transferring the Mcs1 COP allele onto a Wistar Furth (WF) genetic background. Male carriers were genotyped using microsatellite markers spanning 20-30 cM of the Mcs1 locus. One of the congenic lines minimally retained the COP allele at D2Mit29 on the centromeric end of chromosome 2 and extended distally to D2Rat201. Heterozygous Mcs1 carrier rats were interbred, and the female offspring were treated with DMBA. The female rats from the Mcs1 congenic line that carried one or two COP alleles of the Mcs1 region had a significantly reduced (65 and 85%, respectively) tumor development (P < 0.001) compared with rats carrying zero COP alleles at this locus. A WF.COP-D2Mit29/D2Rat201 homozygous congenic strain derived at the N10 generation was treated with DMBA, and the COP homozygous rats developed 1.5 +/- 0.3 carcinomas/rat versus 6.3 +/- 0.5 in WF control rats (P < 0.0001). Fine mapping of this congenic interval using several recombinant lines identified three genetic loci within the Mcs1 congenic region that independently supported a tumor resistance phenotype. These genetic loci have been termed Mcs1a, Mcs1b, and Mcs1c. In rats for which each locus was homozygous for the COP allele, tumor development was reduced by approximately 60% compared with littermate controls. The identification of these independent loci within the Mcs1 COP allele provide a model of the genetic complexity of cancer.  相似文献   
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Olsen is right to note what can be done with a good theory and the right machine. His particular theory, however, is not transferable to literary studies. If we need a new model, I would suggest that cognitive science can provide a few interesting ones. I have begun to do some work based on David Marr's VISION, in which he hypothesizes two levels of processing within the visual module. My speculation has been on the parallel existence of distinguishable levels of conceptual or language organization which would correspond to the viewer and object centered perspectives Marr describes for vision. I propose to explore the possibility that we may find here the model for the existence of stylistic individualism within overarching historical stylistic generalizations, and even more, that this may be what feminists are searching for when they try to resist being coopted by the masculine language of objectivity. Ellen Spolsky teaches English literature and literary theory and is the Director of the Lechter Institute for Literary Research at Bar-Ilan University, Israel. Her latest book is Gaps in Nature: Literary Interpretation and the Modular Mind(SUNY Press, 1993).  相似文献   
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