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Full-Text Articles in Life Sciences

Runx2 Is Essential For Larval Hyobranchial Cartilage Formation In Xenopus Laevis, Ryan Kerney, Joshua Gross, James Hanken Dec 2006

Runx2 Is Essential For Larval Hyobranchial Cartilage Formation In Xenopus Laevis, Ryan Kerney, Joshua Gross, James Hanken

Ryan Kerney

The vertebrate transcription factor protein Runx2 is regarded as a “master regulator” of bone formation due to the dramatic loss of the osseous skeleton in the mouse homozygous knockout. However, Runx2 mRNA also is expressed in the pre-hypertrophic cartilaginous skeleton of the mouse and chicken, where its developmental function is largely unknown. Several tiers of Runx2 regulation exist in the mouse, any of which may account for its seeming biological inactivity during early stages of skeletogenesis. Unlike mouse and chicken, zebrafish require Runx2 function in early cartilage differentiation. The present study reveals that the earlier functional role of Runx2 in …


Cranial Ontogeny In Philautus Silus (Anura: Ranidae: Rhacophorinae) Reveals Few Similarities With Other Direct-Developing Anurans, Ryan Kerney, Madhava Meegaskumbura, Kelum Manamendra-Arachchi, James Hanken Dec 2006

Cranial Ontogeny In Philautus Silus (Anura: Ranidae: Rhacophorinae) Reveals Few Similarities With Other Direct-Developing Anurans, Ryan Kerney, Madhava Meegaskumbura, Kelum Manamendra-Arachchi, James Hanken

Ryan Kerney

Direct development has evolved in rhaco- phorine frogs independently from other anuran lineages, thereby offering an opportunity to assess features associ- ated with this derived life history. Using a developmen- tal series of the direct-developing Philautus silus (Ranidae: Rhacophorinae) from Sri Lanka, we examine features of cranial morphology that are part of a suite of adaptations that facilitate feeding in free-living tadpoles, but have been changed or lost in other direct-developing lineages. Larval-specific upper jaw cartilages, which are absent from many non-rhacophorine direct-developing species (such as Eleutherodactylus coqui), develop in embryos of P. silus. Similarly, lower jaw cartilages ini- tially …


Sustainable Brackish Water Shrimp Farming – A Serious Thought In India., Ahmed Mustafa, Maryam Moshref, Susmita Patnaik Dec 2006

Sustainable Brackish Water Shrimp Farming – A Serious Thought In India., Ahmed Mustafa, Maryam Moshref, Susmita Patnaik

Ahmed Mustafa Dr.

No abstract provided.


La Cueva De Los Pocitos (El Hierro): Descricpion Y Biocenosis, S. De La Cruz, Ana Reboleira, Eduardo Muñoz, Nieves Zurita, Pedro Oromí Dec 2006

La Cueva De Los Pocitos (El Hierro): Descricpion Y Biocenosis, S. De La Cruz, Ana Reboleira, Eduardo Muñoz, Nieves Zurita, Pedro Oromí

Ana Sofia P.S. Reboleira

The survey and a geomorphological description of Cueva de los Pocitos lava tube is presented. The results of measuring the environmental parameters are provided, as well as those of a faunistic study carried out in the spring and fall of 2000. A total of 552 of arthropods were collected, belonging to at least 30 different species, 8 of them being troglobites. A comparison with the faunistic richness of the other caves of El Hierro is also made.


Tackling Biocomplexity With Meta-Models For Species Risk Assessment, Philip J. Nyhus, Robert C. Lacy, Francis R. Westley, Philip S. Miller, Harrie Harrie Vredenburg, Paul C. Paquet, John Pollak Dec 2006

Tackling Biocomplexity With Meta-Models For Species Risk Assessment, Philip J. Nyhus, Robert C. Lacy, Francis R. Westley, Philip S. Miller, Harrie Harrie Vredenburg, Paul C. Paquet, John Pollak

Philip J. Nyhus

We describe results of a multi-year effort to strengthen consideration of the human dimension into endangered species risk assessments and to strengthen research capacity to understand biodiversity risk assessment in the context of coupled human-natural systems. A core group of social and biological scientists have worked with a network of more than 50 individuals from four countries to develop a conceptual framework illustrating how human-mediated processes influence biological systems and to develop tools to gather, translate, and incorporate these data into existing simulation models. A central theme of our research focused on (1) the difficulties often encountered in identifying and …