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1.
Evidence increasingly links a high-fat, low-fiber diet to coronary heart disease and certain site cancers, indicating a need for large-scale dietary change. Studies showing the effectiveness of particular procedures in specific settings are important at this point. The present study, using an A-B-A-B design and sales data from computerized cash registers, replicated and extended previous work by showing that inexpensive prompts (i.e., signs and fliers) in a national fast-food restaurant could increase the sales of salads, a low-fat, high-fiber menu selection. Suggestions also are made pertinent to more widespread use of the procedures.  相似文献   
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Visual symmetry recognition by pigeons   总被引:6,自引:0,他引:6  
Summary Pigeons learned to discriminate a large number of bilateral symmetric and asymmetric visual patterns successively projected on the pecking-key of an operant conditioning chamber. Responses to the positive stimuli were reinforced according to a variable interval schedule. Once acquisition was complete generalization trials, involving sets of new stimuli, were instituted under extinction. The birds classified these novel test stimuli with high accuracy throughout, according to their symmetry or asymmetry. Their performance was not disturbed by sets of test stimuli whose geometrical style differed considerably from the training stimuli. Pigeons were even able to discriminate when only allowed the use of one eye. The generalization series were partly designed to test some classical symmetry recognition theories. None was found to be adequate. Subsidiary experiments suggested that most pigeons have a slight spontaneous preference for asymmetric patterns and that symmetry/asymmetry differences can aid pattern discrimination learning at an early stage. It is concluded that pigeons, much like humans, can discriminate bilaterally symmetric from non-symmetric visual forms in a concept-like, generalizing way. The ontogenetic and phylogenetic development of this competence is considered. A novel symmetry recognition hypothesis based on spatial frequency analysis and neuronal feature-detector considerations is proposed.  相似文献   
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The field of genetic counseling faces a broad challenge: many potential clients may not be aware of the value and benefit of genetic counseling services, and therefore may not utilize those services. Navigenics is a personal genomic testing company that provides telephonic genetic counseling services for multifactorial diseases and pharmacogenetics. When first offered in 2008, utilization of the Navigenics genetic counseling service was less than expected. To explore the basis for under-utilization and potential mechanisms for increasing uptake, Navigenics initiated a quality improvement study, in which three different methods of engaging clients in the uptake of genetic counseling services were assessed over the course of 1 year. Outcomes showed significant differences in uptake rates between methodologies (7.5%, 24.6%, and 60.1%), yielding an 8-fold increase in service utilization when post-test telephonic outreach to all clients was performed. Further, utilization spanned all risk levels based on client results, evidence that not only clients with high-risk results were motivated to engage in the genetic counseling service. This research indicates that implementing strategies to educate clients about genetic counseling can positively impact client engagement and utilization of available services.  相似文献   
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Marek Nowak 《Studia Logica》2014,102(1):93-116
There are well-known isomorphisms between the complete lattice of all partitions of a given set A and the lattice of all equivalence relations on A. In the paper the notion of partition is generalized in order to work correctly for wider classes of binary relations than equivalence ones such as quasiorders or tolerance relations. Some others classes of binary relations and corresponding counterparts of partitions are considered.  相似文献   
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When multistable displays (stimuli consistent with two or more equally plausible perceptual interpretations) are presented intermittently, their perceptions are stabilized by sensory memory. Independent memory traces are generated not only for different types of multistable displays (Maier, Wilke, Logothetis, & Leopold, Current Biology 13:1076–1085, 2003), but also for different ambiguous features of binocular rivalry (Pearson & Clifford, Journal of Vision 4:196–202, 2004). In the present study, we examined whether a similar independence of sensory memories is observed in structure-from-motion (SFM), a multistable display with two ambiguous properties. In SFM, a 2-D planar motion creates a vivid impression of a rotating 3-D volume. Both the illusory rotation and illusory depth (i.e., how close parts of an object appear to the observer) of an SFM object are ambiguous. We dissociated the sensory memories of these two ambiguous properties by using an intermittent presentation in combination with a forced-ambiguous-switch paradigm (Pastukhov, Vonau, & Braun, PLoS ONE 7:e37734, 2012). We demonstrated that the illusory depth of SFM generates a sensory memory trace that is independent from that of illusory rotation. Despite this independence, the specificities levels of the sensory memories were identical for illusory depth and illusory rotation. The history effect was weakened by a change in the volumetric property of a shape (whether it was a hollow band or a filled drum volume), but not by changes in color or size. We discuss how these new results constrain models of sensory memory and SFM processing.  相似文献   
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Many reports independently confirm that even more than a quarter of a century after the collapse of the Soviet Union, the results of research and development in those countries that were under its influence are insufficient in comparison to the rest of the world. Given that human intelligence is not distributed unevenly and that science is a powerful driving force for the future of an economy, there is a hidden problem, which, if it can be resolved, may release great economic potential. The first generation of researchers from Armenia, Czech Republic, Georgia, Slovakia and Ukraine, who successfully completed their education after the political revolution, were surveyed. The survey revealed many similarities with regards to ethics, but that there is mounting evidence that the main cause of the current situation is the state of the local legal systems. The conclusion was drawn that a conceptual change in staffing within the relevant legal systems is required to release potential and stimulate wealth creation.  相似文献   
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Effective communication between patients and health professionals is a key component of patient-centred care. Although there is a large body of literature focusing on doctor-patient communication, there has been limited research related to dentist-patient communication, especially presented from the dentists’ perspective. The aim of our study was to explore UK dentists’ perceptions of communication in their consultations, and the factors they perceive may influence this. We conducted semi-structured interviews with eight dentists in UK dental NHS practices. Thematic analysis revealed three themes (‘Treating the whole person’, ‘Barriers to patient-centred communication’ and ‘Mutuality of communication’), which reflected the dentists’ perceptions of their own communication during consultations, the patients’ interaction skills, attitudes (and characteristics that may affect them), and external factors, such as time constraints, that can influence dentist-patients’ encounters. These in-depth accounts are valuable, in that we see what dentists perceive is important, obstructive and facilitative. They report using a patient-centred approach in their everyday dental practice; however this is often difficult due to factors such as time constraints. Although they emphasized that the patient has an active role to play in the communication process, it may be the case that they also need to play their part in facilitating this.  相似文献   
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