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Karyotypes Of Eight Species Of Leptodactylus (Anura, Leptodactylidae) With A Description Of A New Karyotype For The Genus, Renata Cecília Amaro-Ghilardi, Gabriel Skuk, Rafael O. De Sá, Miguel Trefaut Rodrigues, Yatiyo Yonenaga-Yassuda Dec 2006

Karyotypes Of Eight Species Of Leptodactylus (Anura, Leptodactylidae) With A Description Of A New Karyotype For The Genus, Renata Cecília Amaro-Ghilardi, Gabriel Skuk, Rafael O. De Sá, Miguel Trefaut Rodrigues, Yatiyo Yonenaga-Yassuda

Biology Faculty Publications

Karyotypes of eight species of Leptodactylus (Anura, Leptodactylidae) with a description of a new karyotype for the genus. Eight species of the Neotropical genus Leptodactylus were karyologically studied: seven of them (L. gracilis, L. mystacinus, L. petersii, L. pustulatus, L. macrosternum, L. ocellatus, L. labyrinthicus) presented 2n=22 and L. silvanimbus showed a distinctive karyotype with 2n=24. Nucleolar organizer regions (Ag-NORs) were detected in two different pairs of chromosomes: pair 4 at the proximal region of the long arm of one individual of L. mystacinus from São Paulo state and of L. petersii; and …


Genetic Resolution Of The Enigmatic Lesser Antillean Distribution Of The Frog Leptodactylus Validus (Anura, Leptodactylidae), Keneth Yanek, W. R. Heyer, Rafael O. De Sá Dec 2006

Genetic Resolution Of The Enigmatic Lesser Antillean Distribution Of The Frog Leptodactylus Validus (Anura, Leptodactylidae), Keneth Yanek, W. R. Heyer, Rafael O. De Sá

Biology Faculty Publications

Leptodactylus validus has an unusual distribution, inhabiting Trinidad, Tobago, and the Lesser Antilles, but not the mainland of South America. This distribution is inconsistent with other distribution patterns observed for these islands. Although slight variation in adult morphology has been observed among the different island populations of L. validus, call data suggest the presence of a single species. Calls of L. pallidirostris from Venezuela and Brazil suggested that this taxon might be conspecific with L. validus. Sequence data from the 12S and 16S mt rDNA genes indicate that L. validus represents a single species throughout its distribution and is conspecific …


Rana Ocellata Linnaeus, 1758 (Currently Leptodactylus Ocellatus; Amphibia, Anura): Proposed Conservation Of Usage Of The Specific Name By The Designation Of A Neotype, W. Ronald Heyer, Ulisses Caramaschi, Rafael O. De Sá Sep 2006

Rana Ocellata Linnaeus, 1758 (Currently Leptodactylus Ocellatus; Amphibia, Anura): Proposed Conservation Of Usage Of The Specific Name By The Designation Of A Neotype, W. Ronald Heyer, Ulisses Caramaschi, Rafael O. De Sá

Biology Faculty Publications

The purpose of this application, under Article 75.6 of the Code, is to conserve the usage of the specific name of Rana ocellata Linnaeus, 1758 for a species of leptodactylid frog from South America by the designation of a neotype. Prevailing usage of the name is threatened by the identity of the type specimen which is a different species than that which is currently known as Leptodactylus ocellatus. It is proposed that all name-bearing types be set aside and a neotype designated in accord with prevailing usage.


Frozen Beetle Treats Are Environmentally Friendly, W. John Hayden Aug 2006

Frozen Beetle Treats Are Environmentally Friendly, W. John Hayden

Biology Faculty Publications

At my rural household, the most vexatious insect pest has got to be the ubiquitous Japanese beetle. Native to Japan, these pests have infested most of eastern North America, with isolated infestations appearing in some western states. One reason that Japanese beetles are so bad is that they deliver a double-whammy: the larvae (grubs) consume roots and are particularly destructive of turf and pasture grasses while the adults consume leaves and flowers of a wide variety of plants, leaving behind skeletonized versions of the plant parts consumed.


Be Creative When Controlling Invasive Plant Species, W. John Hayden Jun 2006

Be Creative When Controlling Invasive Plant Species, W. John Hayden

Biology Faculty Publications

We are often told that every cloud has a silver lining, but when it comes to invasive exotic species, it seems that the proverbial silver lining is vanishingly thin. Invasives like kudzu, Japanese honeysuckle, tree-of-heaven, and oh-so-many others, seem ubiquitous, crowding out native plants and altering all manner of ecological interactions. Like a rock tossed in a placid pond, the negative impact of an exotic species can ripple throughout the entire ecological community. Further, populations of invasive plants can be so large and so extensive across the countryside that complete eradication is simply out of the question. The genie is …


The Distress Calls Of Leptodactylus Chaquensis Cei, 1950 And Leptodactylus Elenae Heyer, 1978 (Anura: Leptodactylidae), José M. Padial, Rafael O. De Sá, Ignacio De La Riva Feb 2006

The Distress Calls Of Leptodactylus Chaquensis Cei, 1950 And Leptodactylus Elenae Heyer, 1978 (Anura: Leptodactylidae), José M. Padial, Rafael O. De Sá, Ignacio De La Riva

Biology Faculty Publications

We describe the distress calls of Leptodactylus chaquensis and Leptodactylus elenae. They each consist of a single, long, tonal sound with complex harmonic structure and complex frequency modulation. The distress calls of both species are different from their respective advertisement calls. Moreover, there are also clear interspecific differences. Harmonic frequencies in L. elenae are higher, there are fewer emphasized harmonics and the call is shorter and repeated at a higher rate (sometimes paired) than the call of L. chaquensis. Call duration, call rate, and position of the dominant harmonic change with the strength of the stimulus that the …


Phylogenetic Analyses Of Mtdna Sequences Reveal Three Cryptic Lineages In The Widespread Neotropical Frog Leptodactylus Fuscus (Schneider, 1799) (Anura, Leptodactylidae), Arley Camargo, Rafael O. De Sá, W. Ronald Heyer Feb 2006

Phylogenetic Analyses Of Mtdna Sequences Reveal Three Cryptic Lineages In The Widespread Neotropical Frog Leptodactylus Fuscus (Schneider, 1799) (Anura, Leptodactylidae), Arley Camargo, Rafael O. De Sá, W. Ronald Heyer

Biology Faculty Publications

Leptodactylus fuscus is a neotropical frog ranging from Panamá to Argentina, to the east of the Andes mountains, and also inhabiting Margarita, Trinidad, and the Tobago islands. We performed phylogenetic analyses of 12S rRNA, 16S rRNA, tRNA-Leu, and ND1 mitochondrial (mt) DNA sequences from specimens collected across the geographic distribution of L. fuscus to examine two alternative hypotheses: (i) L. fuscus is a single, widely distributed species, or (ii) L. fuscus is a species complex. We tested statistically for geographic association and partitioning of genetic variation among mtDNA clades. The mtDNA data supported the hypothesis of several cryptic species within …


Woy '06: Spicebush Provides A Salad Bar To Some Caterpillars, W. John Hayden Feb 2006

Woy '06: Spicebush Provides A Salad Bar To Some Caterpillars, W. John Hayden

Biology Faculty Publications

While many wildflower enthusiasts appreciate spicebush (Lindera benzoin), the 2006 Virginia Wildflower of the Year, for its subtle beauty, plant ecologists have found this humble shrub to be a fruitful subject for scientific inquiry. The notes that follow relay just a few of the interesting nuggets that can be gleaned from a cursory study of the scientific literature about this plant.


The Southern Family Farm As Endangered Species: Possibilities For Survival In Barbara Kingsolver's Prodigal Summer, Suzanne W. Jones Jan 2006

The Southern Family Farm As Endangered Species: Possibilities For Survival In Barbara Kingsolver's Prodigal Summer, Suzanne W. Jones

English Faculty Publications

At the same time some southern studies scholars are positioning the U.S. South in a larger cultural, historic, and economic region that encompasses the Caribbean and Latin America, some southern environmentalist writers, such as long-time essayist and novelist Wendell Berry and activist-turned-memoirist Janisse Ray, are finding a pressing need to focus on smaller bioregions and the locatedness of the human subject. These writers believe that agribusiness and consumer ignorance are driving small farmers out of business and that clear-cutting timber and farming practices dependent on chemicals are threatening local ecosystems. Best-selling novelist Barbara Kingsolver has joined their ranks. With her …


Non-Competition Agreements And Research Productivity In The Biotechnology Industry, Porcher L. Taylor Iii, Joseph E. Coombs Jan 2006

Non-Competition Agreements And Research Productivity In The Biotechnology Industry, Porcher L. Taylor Iii, Joseph E. Coombs

School of Professional and Continuing Studies Faculty Publications

This paper examines the impact of the state-level legal structure, namely the legal support for non-competition agreements, on research productivity. Specifically, we study how California’s unique lack of non-competition agreement laws influences product develop when controlling for local munificence and firm-level technological capability. Our results indicate that California’s unique legal structure is negatively associated with research productivity as measured by the number of products in development at the time a biotechnology firm goes public. Further, firm size moderates this relationship such that the effect is stronger for smaller biotechnology firms.


Leptodactylus Fragilis (Brocchi): White-Lipped Thin-Toed Frog, Miriam M. Heyer, W. Ronald Heyer, Rafael O. De Sá Jan 2006

Leptodactylus Fragilis (Brocchi): White-Lipped Thin-Toed Frog, Miriam M. Heyer, W. Ronald Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus fragilis are small. The head is longer than wide, and the hind limbs are moderately long (Table 1; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are laterally expanded and range from lightly gray speckled to darkly pigmented. Male snout is spatulate; female snout is rounded. Male forearms are not hypertrophied and males lack asperities on the thumbs and chest. The dorsum is spotted or blotched with dark markings, which are often chevron-shaped and sometimes confluent. The supratympanic fold is dark brown. A pair of dorsolateral folds …


2006 Wildflower Of The Year: Spicebush, Lindera Benzoin, W. John Hayden Jan 2006

2006 Wildflower Of The Year: Spicebush, Lindera Benzoin, W. John Hayden

Biology Faculty Publications

Spicebush is a multistemmed deciduous shrub that grows to a height of one to three meters. Young stems are delicate and may be smooth or finely hairy. Leaves are alternate and simple, with an elliptic to obovate blade that tapers at both the base and apex and is bounded by a smooth margin. Examined closely, the margin will reveal a series of fine hairs that project directly out from the leaf edge. In size, leaves are neither remarkably large nor small; they range from one to six inches in length and up to about two and a half inches wide, …


Leptodactylus Fragilis, Mirriiam Muedeking Heyer, W. Ronald Heyer, Rafael O. De Sá Jan 2006

Leptodactylus Fragilis, Mirriiam Muedeking Heyer, W. Ronald Heyer, Rafael O. De Sá

Biology Faculty Publications

Leptodactylus fragilis (Brocchi) White-lipped thin-toed frogs are characteristically defined according to their habitation and age. There is a diagnosis of different species group within Leptodactylus. It is furthermore described from different perspectives and discoveries such as its eggs and karyotype. The distribution of the frog is considered to be prominent occurring form Southernmost Teaxs throughout Mexico and Middle America expanding to Venezuela. The fossil fuel records and literature on Leptodactylus are slighly viewed before studying its nomenclatural history and rarity.


The Amphibian Tree Of Life, Darrel R. Frost, Taran Grant, Julián Faivovich, Raoul H. Bain, Alexander Haas, Célio F.B. Haddad, Rafael O. De Sá Jan 2006

The Amphibian Tree Of Life, Darrel R. Frost, Taran Grant, Julián Faivovich, Raoul H. Bain, Alexander Haas, Célio F.B. Haddad, Rafael O. De Sá

Biology Faculty Publications

The evidentiary basis of the currently accepted classification of living amphibians is discussed and shown not to warrant the degree of authority conferred on it by use and tradition. A new taxonomy of living amphibians is proposed to correct the deficiencies of the old one. This new taxonomy is based on the largest phylogenetic analysis of living Amphibia so far accomplished. We combined the comparative anatomical character evidence of Haas (2003) with DNA sequences from the mitochondrial transcription unit H1 (12S and 16S ribosomal RNA and tRNAValine genes, ø 2,400 bp of mitochondrial sequences) and the nuclear genes histone H3, …


Development Of Proliferation Assays To Explore The Role Of Calcium Activated Potassium Channels In Cell Proliferation, Sean Foster Jan 2006

Development Of Proliferation Assays To Explore The Role Of Calcium Activated Potassium Channels In Cell Proliferation, Sean Foster

Honors Theses

Due to the large variety of Kchannel families implicated in cancer cell proliferation, it is desirable to develop techniques capable of quickly and reliably screening a variety of potential channels for a role in proliferation. While there are many established cell counting procedures, the time-consuming nature of such protocols limits their usefulness in broadly identifying particular channels in uncharacterized cell lines. For this reason, a primary goal of the present research was the development of techniques capable of implicating particular ion channels in proliferation with both qualitative and quantitative data. Once this goal was accomplished, the project sought …


The Presence, Prevalence And Antibiotic Resistance Of Microbes In The Pamunkey River Basin, Christina Mcdowell Jan 2006

The Presence, Prevalence And Antibiotic Resistance Of Microbes In The Pamunkey River Basin, Christina Mcdowell

Honors Theses

This project examined the presence, prevalence and antibiotic resistance of Coliforms (mainly Escherichia coli), Staph/occocus aureus, fecal Streptococcus, andEnterobacteriacae found in the water samples taken from three selected sites on the North Anna, South Anna, and Little Rivers of the Pamunkey River Basin. The diversity and concentration of the microbes isolated from these sites was evaluated in late January and late March allowing for a comparison of the occurrence of microbes at different times and between the different sites. Over the course of two months the concentration of colonies increased based on colony counts from Nutrient agar. The rate of …


The Effect Of Tgf-B And Egf On Mmp-2 Activation And Mt1-Mmp Phosphorylation In U87mg And T98g Human Glioma Cells, Jacquelyn B. Knupp Jan 2006

The Effect Of Tgf-B And Egf On Mmp-2 Activation And Mt1-Mmp Phosphorylation In U87mg And T98g Human Glioma Cells, Jacquelyn B. Knupp

Honors Theses

Glioblastoma multiforme (GBM), a high-grade, malignant brain tumor of astrocyte origin, invades normal brain tissue and most often results in death ofthe patient withinayearofdiagnosis. In order to invade the surrounding tissue and thereby metastasize, these tumor cells must migrate through the extracellular matrix. The pmpose ofthis research project is to investigate the family ofmatrix metalloproteinases responsible for extracellular degradation. Specifically, this investigation looks at MMP-2 activation via MT 1-MMP and the possible importance of phosphorylation of the tyrosine residue on the cytoplasmic tail of MTl-MMP. U87wildtypegliomacellsaswellasT98 p53 mutant glioma cells were treated with transforming growth factor beta (TGF-P). Preliminary results …


The Effects Of P53 Status And Egf On Timp-2 And Other Proteins Related To Migration In Human Glioblastoma Cell Cultures, Lisa M. Lint Jan 2006

The Effects Of P53 Status And Egf On Timp-2 And Other Proteins Related To Migration In Human Glioblastoma Cell Cultures, Lisa M. Lint

Honors Theses

The effects of epidermal growth factor (EGF) on proteins that have been implicated in the migration of the Grade IV brain tumor, glioblastoma multiforme, were investigated in this study. Differential expression levels of TIMP-2, MMP-2, and MT1-MMP in response to EGF treatment were compared by immunoprecipitation, and immunoblotting. This study involved two different cultured glioma cell lines, U87, which expresses wild-type p53, and T98, which has a mutation in the p53 gene, in order to determine if the status of the p53 tumor suppression gene is a factor in the regulation of proteins involved in this migration pathway. It was …