Matthew Spencer

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To determine the frequency and distribution of mitochondrial DNA mutations in breast cancer, 18 primary breast tumors were analyzed by direct sequencing. Twelve somatic mutations not present in matched lymphocytes and normal breast tissues were detected in 11 of the tumors screened (61%). Of these mutations, five (42%) were deletions or insertions in a(More)
Magnetic resonance (MR) imaging is useful in the characterization of renal masses. The MR imaging manifestations and pathologic diagnoses of 82 renal masses were reviewed and correlated. The MR imaging appearance of clear cell type renal cell carcinoma varies depending on the presence of cystic components, hemorrhage, and necrosis. Papillary renal cell(More)
This work presents measured results from test chips containing circuits implemented with micro-electro-mechanical (MEM) relays. The relay circuits designed on these test chips illustrate a range of important functions necessary for the implementation of integrated VLSI systems and lend insight into circuit design techniques optimized for the physical(More)
Evolutionary rates vary among sites and across the phylogenetic tree (heterotachy). A recent analysis suggested that parsimony can be better than standard likelihood at recovering the true tree given heterotachy. The authors recommended that results from parsimony, which they consider to be nonparametric, be reported alongside likelihood results. They also(More)
Many kinds of adaptive behavior, including responses to risk of predation, have been documented, but there have been few attempts to translate these behaviors into consequences for populations. We present one of the first models to predict the consequences of adaptive behavior for population size in a specific natural system. Larvae of the mosquito Culiseta(More)
Expression of the mouse whey acidic protein (WAP) gene is specific to the mammary gland, is induced several thousand-fold during pregnancy, and is under the control of steroid and peptide hormones. To study developmental regulation of the mouse WAP gene, a 7.2-kilobase (kb) WAP transgene, including 2.6 kb of 5'- and 1.6 kb of 3'-flanking sequences, was(More)
The covarion hypothesis of molecular evolution proposes that selective pressures on an amino acid or nucleotide site change through time, thus causing changes of evolutionary rate along the edges of a phylogenetic tree. Several kinds of Markov models for the covarion process have been proposed. One model, proposed by Huelsenbeck (2002), has 2 substitution(More)
Genome phylogenies can be inferred from data on the presence and absence of genes across taxa. Logdet distances may be a good method, because they allow expected genome size to vary across the tree. Recently, Lake and Rivera proposed conditioned genome reconstruction (calculation of logdet distances using only those genes present in a conditioning genome)(More)
The present study characterized the structure, organization, and expression of the rat cardiac myosin light chain (MLC) -2 gene. The rat cardiac MLC-2 gene has seven exons which display complete conservation with the exon structure of the rat fast twitch skeletal MLC-2 gene. A 250-base pair (bp) sequence of the 5'-flanking region contains CArG motifs and(More)
BACKGROUND The reconstruction of biological processes and human activities during the last glacial cycle relies mainly on data from biological remains. Highly abundant tissues, such as wood, are candidates for a genetic analysis of past populations. While well-authenticated DNA has now been recovered from various fossil remains, the final 'proof' is still(More)