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Roberto Arrighi Fortunato Tito Arecchi Alessandro Farini Carolina Gheri 《Cognitive processing》2009,10(Z1):95-99
The term perceptual bistability refers to all those conditions in which an observer looks at an ambiguous stimulus that can
have two or more distinct but equally reliable interpretations. In this work, we investigate perception of Necker Cube in
which bistability consists of the possibility to interpret the cube depth in two different ways. We manipulated the cube ambiguity
by darkening one of the cube faces (cue) to provide a clear cube interpretation due to the occlusion depth index. When the
position of the cue is stationary the cube perceived perspective is steady and driven by the cue position. However, when we
alternated in time the cue position (i.e. we changed the position of the darkened cube face) two different perceptual phenomena
occurred: for low frequencies the cube perspective alternated in line with the position of the cue; however for high frequencies
the cue was no longer able to bias the perception but it appears as a floating feature traveling across the solid with the
cube whole perspective that returns to be bistable as in the conventional, bias-free, case. 相似文献
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Flannelly KJ Galek K Tannenbaum HP Handzo GF 《The journal of pastoral care & counseling : JPCC》2007,61(1-2):19-29
The authors conducted an electronic search of the Medline database for articles measuring family satisfaction. Content analysis was then performed on the relevant studies to determine the types of themes included in scales measuring family satisfaction in healthcare settings. The authors used these themes to develop a scale for measuring the effectiveness of pastoral care with family members. A convenience sample of chaplains that was asked to judge the usefulness of each of the scale items, rated them all, on average, to be "somewhat useful" to "very useful" for evaluating chaplains' effectiveness. The value of the scale is discussed in terms of its being a more outcome-oriented measure of effectiveness compared to typical family satisfaction instruments. 相似文献
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Joseph L Verheijde Mohamed Y Rady Joan L McGregor 《Philosophy, ethics, and humanities in medicine : PEHM》2007,2(1):19
Advance health care directives and informed consent remain the cornerstones of patients' right to self-determination regarding
medical care and preferences at the end-of-life. However, the effectiveness and clinical applicability of advance health care
directives to decision-making on the use of life support systems at the end-of-life is questionable. The Uniform Anatomical
Gift Act (UAGA) has been revised in 2006 to permit the use of life support systems at or near death for the purpose of maximizing
procurement opportunities of organs medically suitable for transplantation. Some states have enacted the Revised UAGA (2006)
and a few of those have included amendments while attempting to preserve the uniformity of the revised Act. Other states have
introduced the Revised UAGA (2006) for legislation and remaining states are likely to follow soon. 相似文献