Data mining in a behavioral test detects early symptoms in a model of amyotrophic lateral sclerosis.

"What's wrong with my genetically engineered animal?" is a common yet often difficult to answer question in behavioral phenotyping. We present here a method termed Pattern Array for mining movement patterns and isolating those that best capture an effect of a genetic manipulation. We demonstrate the method by searching for early motor symptoms in the open-field behavior of SOD1 mutant rats, an animal model of amyotrophic lateral sclerosis. Pattern Array was able to identify a unique motor pattern that differentiated the SOD1 mutants from the wild-type controls 2 months before disease onset. This pattern included heavy braking while moving near the arena wall but turning away from it. SOD1 mutants performed this pattern significantly less than wild-type controls in 2 independent data sets. At such early age the SOD1 mutants could not be differentiated from the controls by standard behavioral measures or by subjective observation. The early discovered symptom may enable investigators to test therapies aimed for intervention rather than remediation. Our results demonstrate the feasibility and potential of detecting subtle behavioral effects using data mining strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phosphate and Silica Adsorption and Desorption from Soils

Phosphate adsorption and desorption in conjunction with silica desorption, were studied on soils of two field experiments. The soil samples were taken from control plots and plots that had received a total of 14 ton/ha superphosphate over a three-year period. Initially, silica desorption was increased by P added in the past as fertilizer and that added in equilibration solutions. Subsequently, after repeated washings, the rate of silica desorption was independent of the previous phosphate treatment. The adsorbed P was completely leached from the high P fertilized samples but not from those of the control. The slow reaction of phosphate with the soil was accompanied by a release of silica to the equilibrium solution. Most of the slow reaction product was not isotopically exchangeable in 48 hr.     

Hydrogen Consumption and Silica Release During Initial Stages of Phosphate Adsorption on Kaolinite at a Constant pH

The release of silica from kaolinite is enhanced immediately after application of phosphate. The rate of the silica release was inferred from the rate of hydrogen additions needed to keep the system at a constant pH. Potassium increases silica hydrolysis from kaolinite surfaces in 1N solution more than calcium or sodium.     

SEE locomotor behavior test discriminates C57BL/6J and DBA/2J mouse inbred strains across laboratories and protocol conditions.

Conventional tests of behavioral phenotyping frequently have difficulties differentiating certain genotypes and replicating these differences across laboratories and protocol conditions. This study explores the hypothesis that automated tests can be designed to quantify ethologically relevant behavior patterns that more readily characterize heritable and replicable phenotypes. It used SEE (Strategy for the Exploration of Exploration) to phenotype the locomotor behavior of the C57BL/6 and DBA/2 mouse inbred strains across 3 laboratories. The 2 genotypes differed in 15 different measures of behavior, none of which had a significant genotype-laboratory interaction. Within the same laboratory, most of these differences were replicated in additional experiments despite the test photoperiod phase being changed and saline being injected. Results suggest that well-designed tests may considerably enhance replicability across laboratories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)