Evidence for heterogeneity of endothelin receptor distribution in human coronary artery

1. The receptors mediating endothelin-evoked contraction of human coronary artery have been investigated in isolated segments of the left anterior descending coronary artery (LAD). 2. Endothelin-1 (ET-1) was 10 times more potent in distal than in proximal segments but the potency ratio between ET-1 and ET-3 (endothelin-3) was similar and close to 100 in any segment of the artery. 3. BQ-123, an ETA receptor antagonist, competitively antagonized the response to ET-1 of distal segments (pA2 equal to 7.47). In the proximal segments, part of the contractile response was BQ123 sensitive, but the antagonism was non-competitive. In both groups of segments, the response to ET-3 could be completely blocked by BQ-123. 4. These observations indicate that ETA receptors mediate the contractile response to ET-1 in distal, pre-resistant coronary arteries, but that other ET receptors are also involved in the contractile response of proximal segments.     

Arousal and attraction: Evidence for automatic and controlled processes.

A meta-analysis, a review, and an experiment investigated the effect of arousal on attraction. The meta-analysis examined experiments that manipulated arousal level. Results indicated that arousal affects attraction even when the arousal source is relatively unambiguous. In contrast, a review of experiments that manipulated arousal source ambiguity suggested that arousal exerts a stronger influence on attraction when arousal sources are greater in ambiguity. The authors proposed a judgment and adjustment model that states that arousal automatically affects judgments of attraction but that individuals can correct (i.e., adjust) for this automatic effect when the arousal source is unambiguous. Consistent with this model, an experiment provided evidence that cognitive busyness interferes with the adjustment process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Anatomic region-based dynamic range compression for chest radiographs using warping transformation of correlated distribution

SCO-spondin is a newly identified protein, strongly expressed in the subcommissural organ (SCO), an ependymal differentiation of the brain. When secreted into the cerebrospinal fluid at the entrance to the Sylvian aqueduct, it condenses and forms Reissner's fiber. Several conserved domains have previously been characterizedin SCO-spondin, e.g., thrombospondin type 1 repeats (TSRs), low-density lipoprotein receptor (LDLr) type A repeats, and epidermal-growth-factor-like domains, which are potent sites of protein-protein interaction. To clarify the role of this protein on neuronal development, we have tested the effect of oligopeptides, the sequences of which include highly conserved amino acids of TSRs, LDLr type A repeats and a potent site of attachment to proteoglycan, on cortical and spinal-cord neurons in primary cell cultures. One of these peptides (WSGWSSCSRSCG), corresponding to a SCO-spondin TSR sequence, markedly increases adhesivity and neuritic outgrowth of cortical neurons and induces an opposite effect on cortical and spinal-cord neuronal aggregation. These effects are specific, as no response is observed with the scrambled sequence of this peptide. Another peptide (WGPCSVSCG) is only slightly active on adhesivity and neuritic outgrowth of cortical neurons and has no effect on spinal-cord neurons. Peptides derived from other conserved domains of SCO-spondin are not effective under our experimental conditions. Thus, SCO-spondin may be responsible for at least a part of the effects previously observed on neuronal cells cultured in the presence of Reissner's fiber. In addition, SCO-spondin seems to interfere with neuronal development and/or axonal guidance during ontogenesis of the central nervous system in modulating side-to-side interactions and neuritic outgrowth.     

Investigation of the possibilities of CCD for controlled distribution of charge

Translated from Metallurg, Vol. 39, No. 10, p. 23, October, 1995.     

Beyond dissociation logic: Evidence for controlled and automatic influences in artificial grammar learning.

Evidence for unconscious learning has typically been based on dissociations between direct and indirect tests of learning. Because of some inherent problems with dissociation logic, we applied the logic of opposition to 2 artificial grammar learning experiments. In Experiment 1, participants were exposed to 2 different sets of letter strings, generated from 2 different grammars, and later rated test strings for grammaticality with either in-concert (rate grammatical strings consistent with either structure) or opposition (rate grammatical only strings from 1 of the structures) instructions. Manipulating response deadline affected controlled, but not automatic influences. In Experiment 2, after similar training, a source-monitoring test was administered from which the in-concert and opposition conditions were derived. The test indicated that varying the retention interval affected controlled, but not automatic, influences. The results are discussed in terms of awareness, knowledge representation, and metacognitive processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The brittle-to-ductile transition in germanium

The brittle-to-ductile transition in precracked germanium crystals has been studied experimentally. Germanium undergoes a “smooth” brittle-ductile transition, where the stress to fracture rises steadily with temperature, associated with dislocation activity around the crack front at temperatures well below the transition temperature. The variation in transition temperature with strain rate yields an activation energy of 1.54 eV, suggesting, as in silicon, that dislocation mobility controls the brittle-ductile transition. Modelling of the experiments, using a computer simulation of the shielding effect of an evolving crack tip dislocation array, fits best with a small distance (∼0.1–0.5 μm) between the dislocation sources at the crack tip. This corresponds to the experimental observation that the dislocations reach the crack during the early stages of the tests and multiply along the crack front to form many crack tip sources.     

Confidence intervals for differences in correlated binary proportions

An experiment to assess the efficacy of a particular treatment or process often produces dichotomous responses, either favourable or unfavourable. When we administer the treatment on two occasions to the same subjects, we often use McNemar's test to investigate the hypothesis of no difference in the proportions on the two occasions, that is, the hypothesis of marginal homogeneity. A disadvantage in using McNemar's statistic is that we estimate the variance of the sample difference under the restriction that the marginal proportions are equal. A competitor to McNemar's statistic is a Wald statistic that uses an unrestricted estimator of the variance. Because the Wald statistic tends to reject too often in small samples, we investigate an adjusted form that is useful for constructing confidence intervals. Quesenberry and Hurst and Goodman discussed methods of construction that we adapt for constructing confidence intervals for the differences in correlated proportions. We empirically compare the coverage probabilities and average interval lengths for the competing methods through simulation and give recommendations based on the simulation results.     

浅孔留矿法平立交替控制爆破技术研究

本文介绍浅孔留矿法平立交替控制爆破新技术，该技术用于采场落矿，既安全，又有利于提高采场落矿指标，对类似矿山有实际参考价值。