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121.
Curie’s Principle says that any symmetry property of a cause must be found in its effect. In this article, I consider Curie’s Principle from the point of view of graphical causal models, and demonstrate that, under one definition of a symmetry transformation, the causal modeling framework does not require anything like Curie’s Principle to be true. On another definition of a symmetry transformation, the graphical causal modeling formalism does imply a version of Curie’s Principle. These results yield a better understanding of the logical landscape with respect to the relationship between Curie’s Principle and graphical causal modeling. 相似文献
122.
This paper develops quantum state individualism, a fundamental ontology for what is usually known as ‘orthodox quantum mechanics.’ The central import of this ontology is that allows for a systematic evaluation of some of the main conclusions of the recent literature on quantum metaphysical indeterminacy. In particular, quantum state individualism supports the ‘gappy’ version of Jessica Wilson's determinable-based account of metaphysical indeterminacy; it implies that fundamental reality is perfectly precise; and third, it provides a non-disjunctive definition of determinables and thereby shields Wilson's account against the charge that it requires either a departure from classical logic or a revision of the quantum formalism. 相似文献
123.
We have each spent more than 50 years doing research that has had little impact. Even more lamentable is that our field, judgment and decision making (JDM), has on the whole had little impact during that span. We attribute that failure to the use of methodologies that emphasize testing models rather than looking for differences in behavior. The “cognitive revolution” led the field astray, toward the goal of studying model fit rather than comparing observable results. With modeling as the goal, experimentation was stultified. Simple tasks became dominant. Although a poor metaphor for real decision making, the gambling paradigm has lasted forever because the inputs to the decision are known to the researcher and thus easily modeled. 相似文献
124.
P M Williams 《Nature》1968,219(5150):152-153
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Mutation of TDP1, encoding a topoisomerase I-dependent DNA damage repair enzyme,in spinocerebellar ataxia with axonal neuropathy 总被引:14,自引:0,他引:14
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A reinvestigation of the type specimen of Araucarioxylon? obscurum Knowlton (1900) from the Upper Jurassic Morrison Formation in the Freezeout Hills of Wyoming has determined that this fossil should be transferred to Mesembrioxylon Seward (1919) as M. obscurum comb. nov. (Knowlton) Medlyn and Tidwell. Knowlton (1900), who was uncertain of its appropriate generic disposition, tentatively referred the wood to Araucarioxylon because it had obscure growth rings and relatively low ray height. Reexamination of Knowltons slides demonstrates that the wood has uniseriate, rarely biseriate rays, podocarpoid pitting, and diffuse axial parenchyma, none of which Knowlton mentioned. Tracheary pitting is mostly separate, round, uniseriate, occasionally biseriate and, when biseriate, opposite to subopposite. The smooth-walled crossfields exhibit 1-3 thin-bordered podocarpaceous pits per field. All of these features are present in Mesembrioxylon Seward. 相似文献
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Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Four near-surface locations in Pyramid Lake, Nevada, were sampled for larval tui chubs ( Gila bicolor ) during summer and early fall 1979. Numbers of larvae collected were highest in mid-July. Zooplankton was the only food eaten throughout the survey; the cladoceran Moina hutchinsoni was the major species eaten at all locations. Another cladoceran, Diaphanosoma leuchtenbergianum, was also important to the diet of pelagic larvae, and the copepod Cyclops vernalis was eaten in significant quantities by nearshore fish. Changes in diet composition of larval tui chubs during summer corresponded to seasonal succession of zooplankton species in Pyramid Lake. 相似文献
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