Friday, February 26th, 2016

K.B. Boomer – Seidl-Adams, I.; Richter, A.; Boomer, K B.; Yoshinaga, N.; and Tumlinson, J. H. “Emission of Herbivore Elicitor-Induced Sesquiterpenes is Regulated by Stomatal Aperture in Maize (Zea mays) Seedlings.” Plant, Cell & Environment 38, no. 1 (2015) : 23-34.

K.B. Boomer, Associate Professor of Mathematics

Maize seedlings emit sesquiterpenes during the day in response to insect herbivory. Parasitoids and predators use induced volatile blends to find their hosts or prey. To investigate the diurnal regulation of biosynthesis and emission of induced sesquiterpenes, we applied linolenoyl-L-glutamine (LG) to maize seedlings in the morning or evening using a cut-stem assay and tracked farnesene emission, in planta accumulation, as well as transcript levels of farnesyl pyrophosphate synthase 3 (ZmFPPS3) and terpene synthase10 (ZmTPS10) throughout the following day. Independent of time of day of LG treatment, maximum transcript levels ofZmFPPS3 and ZmTPS10 occurred within 3–4 h after elicitor application. The similarity between the patterns of farnesene emission andin planta accumulation in light-exposed seedlings in both time courses suggested unobstructed emission in the light. After evening induction, farnesene biosynthesis increased dramatically during early morning hours. Contrary to light-exposed seedlings dark-kept seedlings retained the majority of the synthesized farnesene. Two treatments to reduce stomatal aperture, dark exposure at midday, and abscisic acid treatment before daybreak, resulted in significantly reduced amounts of emitted and significantly increased amounts of in planta accumulating farnesene. Our results suggest that stomata not only play an important role in gas exchange for primary metabolism but also for indirect plant defenses.

Seidl-Adams, I.; Richter, A.; Boomer, K B.; Yoshinaga, N.; and Tumlinson, J. H. “Emission of Herbivore Elicitor-Induced Sesquiterpenes is Regulated by Stomatal Aperture in Maize (Zea mays) Seedlings.” Plant, Cell & Environment 38, no. 1 (2015) : 23-34.

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Friday, February 26th, 2016

K.B. Boomer – Evans, David W.; Lazar, Steven M.; Boomer, K B.; Mitchel, Aaron; Michael, Andrew M.; and Moore, Gregory J. “Social Cognition and Brain Morphology: Implications for Developmental Brain Dysfunction.” Brain Imaging and Behavior 9, no. 2 (2015) : 264-274.

K.B. Boomer, Associate Professor of Mathematics

The social-cognitive deficits associated with several neurodevelopmental and neuropsychiatric disorders have been linked to structural and functional brain anomalies. Given the recent appreciation for quantitative approaches to behavior, in this study we examined the brain-behavior links in social cognition in healthy young adults from a quantitative approach. Twenty-two participants were administered quantitative measures of social cognition, including the social responsiveness scale (SRS), the empathizing questionnaire (EQ) and the systemizing questionnaire (SQ). Participants underwent a structural, 3-T magnetic resonance imaging (MRI) procedure that yielded both volumetric (voxel count) and asymmetry indices. Model fitting with backward elimination revealed that a combination of cortical, limbic and striatal regions accounted for significant variance in social behavior and cognitive styles that are typically associated with neurodevelopmental and neuropsychiatric disorders. Specifically, as caudate and amygdala volumes deviate from the typical R > L asymmetry, and cortical gray matter becomes more R > L asymmetrical, overall SRS and Emotion Recognition scores increase. Social Avoidance was explained by a combination of cortical gray matter, pallidum (rightward asymmetry) and caudate (deviation from rightward asymmetry). Rightward asymmetry of the pallidum was the sole predictor of Interpersonal Relationships and Repetitive Mannerisms. Increased D-scores on the EQ-SQ, an indication of greater systemizing relative to empathizing, was also explained by deviation from the typical R > L asymmetry of the caudate.

Evans, David W.; Lazar, Steven M.; Boomer, K B.; Mitchel, Aaron; Michael, Andrew M.; and Moore, Gregory J. “Social Cognition and Brain Morphology: Implications for Developmental Brain Dysfunction.” Brain Imaging and Behavior 9, no. 2 (2015) : 264-274.

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Friday, February 26th, 2016

Peter A. Brooksbank – Brooksbank, Peter A. “Polytopes of Large Rank for PSL(4,q).” Journal of Algebra 452, (2016) : 390-400.

Peter A. Brooksbank, Professor of Mathematics

This paper examines abstract regular polytopes whose automorphism group is the projective special linear group PSL(4,q). For q odd we show that polytopes of rank 4 exist by explicitly constructing PSL(4,q) as a string C-group of that rank. On the other hand, we show that no abstract regular polytope exists whose group of automorphisms is PSL(4,2k).

Brooksbank, Peter A. “Polytopes of Large Rank for PSL(4,q).” Journal of Algebra 452, (2016) : 390-400.

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