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Concrete Case (concrete + case)

Distribution by Scientific Domains

Mathematics and Statistics	50%

Selected Abstracts

Statistical methods for the evaluation of health effects of prenatal mercury exposure

ENVIRONMETRICS, Issue 2 2003
Esben Budtz-Jørgensen
Abstract Environmental risk assessment based on epidemiological data puts stringent demands on the statistical procedures. First, convincing evidence has to be established that there is a risk at all. In practice this endeavor requires prudent use of the observational epidemiological information with delicate balancing between utilizing the information optimally but not over-interpreting it. If a case for an environmental risk has been made, the second challenge is to provide useful input that regulatory authorities can use to set standards. This article surveys some of these issues in the concrete case of neurobehavioral effects in Faroese children prenatally exposed to methylmercury. A selection of modern, appropriate methods has been applied in the analysis of this material that may be considered typical of environmental epidemiology today. In particular we emphasize the potential of structural equation models for improving standard multiple regression analysis of complex environmental epidemiology data. Copyright © 2003 John Wiley & Sons, Ltd. [source]

The Krein,von Neumann extension and its connection to an abstract buckling problem

MATHEMATISCHE NACHRICHTEN, Issue 2 2010
Mark S. Ashbaugh
Abstract We prove the unitary equivalence of the inverse of the Krein,von Neumann extension (on the orthogonal complement of its kernel) of a densely defined, closed, strictly positive operator, S , ,IH for some , > 0 in a Hilbert space H to an abstract buckling problem operator. In the concrete case where in L2(,; dnx) for , , ,n an open, bounded (and sufficiently regular) domain, this recovers, as a particular case of a general result due to G. Grubb, that the eigenvalue problem for the Krein Laplacian SK (i.e., the Krein,von Neumann extension of S), SKv = ,v, , , 0, is in one-to-one correspondence with the problem of the buckling of a clamped plate, (-,)2u = , (-,)u in ,, , , 0, u , H02(,), where u and v are related via the pair of formulas u = SF -1 (-,)v, v = , -1(-,)u, with SF the Friedrichs extension of S. This establishes the Krein extension as a natural object in elasticity theory (in analogy to the Friedrichs extension, which found natural applications in quantum mechanics, elasticity, etc.) (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

THIS ARTICLE HAS BEEN RETRACTED CD34-reactive tumors of the skin.

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 12 2008
An updated review of an ever-growing list of lesions
Over the past few years, a growing number of cutaneous tumors expressing CD34 is being reported. The list contains benign and malignant neoplasms as well as reactive and hamartomatous lesions of diverse lineages of differentiation, including fibroblastic, myofibroblastic, fibrohistiocytic, vascular, neural, adipocytic, smooth muscle, hematopoietic, melanocytic and epithelial. The more frequent diagnostic difficulties are found in spindle cell proliferations, mainly in those of the fibrocytic lineage. In part, this is because of the fact that in this area are, aside to well-defined entities, histologically and clinically diverse, recently reported cutaneous CD34-reactive lesions, whose definitions, limits and relationships are not completely established. The CD34 expression plays a key role in the differential diagnosis of some tumors, such as dermatofibrosarcoma protuberans, epithelioid sarcoma (ES) or pleomorphic hyalinizing angiectatic tumor of soft parts, with important therapeutic consequences. In others, as in desmoplastic trichilemmoma, it can help to resolve diagnostic problems in concrete cases. Finally, in many of the CD34-positive lesions, the diagnosis with the hematoxylin and eosin stain is straightforward. However, in all of them, the knowledge of the immunohistochemical profile contributes to our understanding of the cutaneous pathology. [source]

On Law and Disagreement.

RATIO JURIS, Issue 2 2003
Some Comments on "Interpretative Pluralism"
According to both Michelman and Waldron, the epistemic indeterminacy of interpretation,that is, the fact that principles do not possess stable meanings beyond, and independent of, their application to concrete cases,puts its finger on a point of the contractualist and prevailing political theory. But, if neither the legitimacy of any democratic order nor the standard of internal criticism can be founded on a broad background consensus on constitutional essentials, "what else makes a deliberative process of legislation and adjudication a generator of legitimacy so that citizens are induced to accept controversial results as ,worthy of respect'?" The route pursued goes beyond all views that require legitimacy to be based on sharing a set of "thick" ethical beliefs. In this perspective, the author argues that the performative meaning of constitution-making "provides a thin yet sufficiently strong base," which corresponds to the minimal requirements inherent in the very practice of framing a constitution. [source]