Identification of an Efficient Gene Expression Panel for Glioblastoma Classification.

We present here a novel genetic algorithm-based random forest (GARF) modeling technique that enables a reduction in the complexity of large gene disease signatures to highly accurate, greatly simplified gene panels. When applied to 803 glioblastoma multiforme samples, this method allowed the 840-gene Verhaak et al. gene panel (the standard in the field) to be reduced to a 48-gene classifier, while retaining 90.91% classification accuracy, and outperforming the best available alternative methods. Additionally, using this approach we produced a 32-gene panel which allows for better consistency between RNA-seq and microarray-based classifications, improving cross-platform classification retention from 69.67% to 86.07%. A webpage producing these classifications is available at http://simplegbm.semel.ucla.edu

Quantitative Impacts of Lake-Level Stabilization on Material Transfer between Water and Sediment in Newnans Lake, Florida

Spillways at lake outlets reduce water-level fluctuations but may accelerate sedimentation in the lake. In eutrophic Newnans Lake, Florida, a transect of sedimentary profiles, dated with 210Pb and 137Cs by γ-ray spectroscopy, showed threefold increases in accumulation rates of organic matter, total Kjeldahl nitrogen (TKN), and total phosphorus (TP) 1200 m lakeward of a spillway since its construction in 1967. Concentrations of TKN and TP increased 3.5 and 2.4 times, respectively, in sediments deposited since 1967. These increases were progressively less at stations farther from the spillway. Postspillway accumulation of TP was focused toward the dam whereas recent TKN deposition was similar lakewide. Flocculent sediment ( \u3e 90% water) accumulated at 1.4 cm/yr. Dams designed to reduce water-level fluctuations may provide short-term benefits for lake access and navigation but in the long-term may accelerate deposition of nutrient-rich detritus, reduce lake volume, cloud the water, alter plant communities, and change lake productivity

A Comparison of Fish Populations from Natural and Constructed Freshwater Marshes in Central Florida

In Florida, freshwater marshes are constructed as mitigation for wetland loss associated with phosphate strip mining, but little is known regarding the similarity of fish communities in natural and constructed marshes. Fish from five constructed and eight natural marshes were sampled quarterly via throw-traps for one year. Gambusia holbrooki, Heterandria formosa, Poecilia latiuinna, Elassoma everqladei, Fundulus chrysotus, Jordanella floridae, Fundulus rubifrons, and unidentified juvenile centrarchids were found in both constructed and natural marshes, while Lucania goodei was found only in constructed marshes. A comparison between constructed and natural marsh populations showed that differences in mean abundance and biomass at p \u3c 0.05 (Wilcoxon rank-sum teat) were present for G. holbrooki and E. everqladei. Differences in populations may be attributed to differences in conditions found in constructed and natural marshes