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991.
992.
Development of a Tissue Engineered Heart Valve for Pediatrics: A Case Study in Bioengineering Ethics
Merryman WD 《Science and engineering ethics》2008,14(1):93-101
The following hypothetical case study was developed for bioengineering students and is concerned with choosing between two
devices used for development of a pediatric tissue engineered heart valve (TEHV). This case is intended to elicit assessment
of the devices, possible future outcomes, and ramifications of the decision making. It is framed in light of two predominant
ethical theories: utilitarianism and rights of persons. After the case was presented to bioengineering graduate students,
they voted on which device should be released. The results revealed that these bioengineering students preferred the more
reliable (and substantially more expensive) design, though this choice precludes the majority of the world from having access
to this technology. This case is intended to examine and explore where the balance lies between design, cost, and adequate
distribution of biomedical devices. 相似文献
993.
994.
Jiří Hanika 《Journal of Philosophical Logic》2008,37(2):121-140
We investigate the interactions of formula complexity in weak set theories with the axioms available there. In particular,
we show that swapping bounded and unbounded quantification preserves formula complexity in presence of the axiom of foundation
weakened to an arbitrary set base, while it does not if the axiom of foundation is further weakened to a proper class base.
More attention is being paid to the necessary axioms employed in the positive results, than to the combinatorial strength
of the positive results themselves. 相似文献
995.
Faceted Thesauri 总被引:1,自引:0,他引:1
The basic elements of faceted thesauri are described, together with a review of their origins and some prominent examples.
Their use in browsing and searching applications is discussed. Faceted thesauri are distinguished from faceted classification
schemes, while acknowledging the close similarities. The paper concludes by comparing faceted thesauri and related knowledge
organization systems to ontologies and discussing appropriate areas of use. 相似文献
996.
Ferran Casas Germà Coenders Robert A. Cummins Mònica González Cristina Figuer Sara Malo 《Journal of Happiness Studies》2008,9(2):197-205
The relationship between the subjective well-being of parents and their own 12–16-year-old children was explored in a Spanish
sample of N = 266 families. A positive relationship was expected due to both a shared environment and the possibility of the genetic
transmission of subjective well-being ‘set-points’. A positive significant relationship was found for the summated scale of
satisfaction domains forming the Personal Well-being Index, and for the specific domains of health and security for the future.
However, no relationship was found for the other five domains that make up this Index or for satisfaction with life as a whole.
We conclude while these results provide some evidence for the expected influence of a shared environment, they have failed
to provide evidence for high heritability of set-points for subjective well-being. 相似文献
997.
Pierre Le Morvan 《Synthese》2008,162(2):251-264
How is epistemic justification related to knowledge? Is it, as widely thought, constitutive of knowledge? Is it merely a means to knowledge, or merely a means to something else, such as truth? In a recent article in this journal, Hofmann (2005, Synthese, 146(3), 357–369) addresses these questions in attempting to defend an important argument articulated by Sartwell (1992, The Journal of Philosophy, 89(4), 167–180) and reconstructed and criticized by Le Morvan (2002, Erkenntnis: An International Journal of Analytic Philosophy, 56(2), 151–168). This Sartwellian argument purported to show that, since epistemic justification is of merely instrumental value, it is not constitutive of knowledge. In this paper, I argue that Hofmann’s defense of Sartwell fails, but that its failure brings to light some important lessons concerning the nature of justification and its relationship to truth and knowledge. 相似文献
998.
999.
Rämä P 《Cognitive processing》2008,9(1):29-34
Visual system has been proposed to be divided into two, the ventral and dorsal, processing streams. The ventral pathway is
thought to be involved in object identification whereas the dorsal pathway processes information regarding the spatial locations
of objects and the spatial relationships among objects. Several studies on working memory (WM) processing have further suggested
that there is a dissociable domain-dependent functional organization within the prefrontal cortex for processing of spatial
and nonspatial visual information. Also the auditory system is proposed to be organized into two domain-specific processing
streams, similar to that seen in the visual system. Recent studies on auditory WM have further suggested that maintenance
of nonspatial and spatial auditory information activates a distributed neural network including temporal, parietal, and frontal
regions but the magnitude of activation within these activated areas shows a different functional topography depending on
the type of information being maintained. The dorsal prefrontal cortex, specifically an area of the superior frontal sulcus
(SFS), has been shown to exhibit greater activity for spatial than for nonspatial auditory tasks. Conversely, ventral frontal
regions have been shown to be more recruited by nonspatial than by spatial auditory tasks. It has also been shown that the
magnitude of this dissociation is dependent on the cognitive operations required during WM processing. Moreover, there is
evidence that within the nonspatial domain in the ventral prefrontal cortex, there is an across-modality dissociation during
maintenance of visual and auditory information. Taken together, human neuroimaging results on both visual and auditory sensory
systems support the idea that the prefrontal cortex is organized according to the type of information being maintained in
WM. 相似文献
1000.
As bibliographical classification of published journal items affects the denominator in this equation, we investigated how
the numerator and denominator of the impact factor (IF) equation were generated for representative journals in two categories
of the Journal Citation Reports (JCR). We performed a full text search of the 1st-ranked journal in 2004 JCR category “Medicine, General and Internal” (New England Journal of Medicine, NEJM, IF = 38.570) and 61st-ranked journal (Croatian Medical Journal, CMJ, IF = 0.690), 1st-ranked journal in category “Multidisciplinary Sciences” (Nature, IF = 32.182) and journal with a relative rank of CMJ (Anais da Academia Brasileira de Ciencias, AABC, IF = 0.435). Large journals published more items categorized by Web of Science (WoS) as non-research items (editorial material,
letters, news, book reviews, bibliographical items, or corrections): 63% out of total 5,193 items in Nature and 81% out of 3,540 items in NEJM, compared with 31% out of 283 items in CMJ and only 2 (2%) out of 126 items in AABC. Some items classified by WoS as non-original contained original research data (9.5% in Nature, 7.2% in NEJM, 13.7% in CMJ and none in AABC). These items received a significant number of citations: 6.9% of total citations in Nature, 14.7% in NEJM and 18.5% in CMJ. IF decreased for all journals when only items presenting original research and citations to them were used for IF calculation.
Regardless of the journal’s size or discipline, publication of non-original research and its classification by the bibliographical
database have an effect on both numerator and denominator of the IF equation.
Preliminary results of the study were presented at the 2006 ORI Research Conference on Research Integrity, Tampa, FL, December
1–3, 2006. 相似文献