George Becker

Learn More
BACKGROUND In response to the novel influenza A H1N1 outbreak in the NY City area, 6090 patient samples were submitted over a 5-week period for a total of 14,114 viral diagnostic tests, including rapid antigen, direct immunofluorescence (DFA), viral culture and PCR. Little was known about the performance of the assays for the detection of novel H1N1 in the(More)
Four experiments explored how readers use temporal information to construct and update situation models and retrieve them from memory. In Experiment 1, readers spontaneously constructed temporal and spatial situation models of single sentences. In Experiment 2, temporal inconsistencies caused problems in updating situation models similar to those observed(More)
Several methods to compute the prime implicants and the prime implicates of a negation normal form (NNF) formula are developed and implemented. An algorithm PI is introduced that is an extension to negation normal form of an algorithm given by Jackson and Pais. A correctness proof of the PI algorithm is given. The PI algorithm alone is sufficient in a(More)
BACKGROUND B-vitamins (folate, B(12)) are important micronutrients for brain function and essential cofactors for homocysteine (HCY) metabolism. Increased HCY has been related to neurological and psychiatric disorders. We studied the role of the B-vitamins in HCY metabolism in the brain. METHODS We studied blood and cerebrospinal fluid (CSF) samples from(More)
BACKGROUND Increased plasma total homocysteine (tHcy) is a risk factor for neurological diseases, but the underlying pathophysiology has not been adequately explained. METHODS We evaluated concentrations of tHcy, S-adenosyl homocysteine (SAH), S-adenosyl methionine (SAM), folate, and vitamin B(12) in cerebrospinal fluid (CSF) and plasma or serum from 182(More)
In this paper we show how the joint use of metamodeling and ontologies allows to describe domain knowledge for a complex domain. Ontologies are used as stabilized descriptions of a business domain while metamodels allow a fine description of the domain (to be constructed in the initial phases of modeling). We propose to use an ontology for early(More)
Background: Increased plasma total homocysteine (tHcy) is a risk factor for neurological diseases, but the underlying pathophysiology has not been adequately explained. Methods: We evaluated concentrations of tHcy, S-adenosyl homocysteine (SAH), S-adenosyl methionine (SAM), folate, and vitamin B12 in cerebrospinal fluid (CSF) and plasma or serum from 182(More)
Based on a survey of modelers’ practice, we propose a UML-based metamodeling architecture in which the two uppermost layers (meta-metamodeling and metamodeling) are organized into a mirroring structure. Using this architecture we can formally define a semantical integration of metamodels. We propose two applications of such metamodel integration: a(More)
Models have been playing a major role in information system engineering and interoperability: in this paper, we put an emphasis on the complementary role of metamodels. Metamodels are used as a core of two innovative platforms for information system interoperability. The first platform allows to combine formal and informal approaches for both modeling and(More)