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Vinylic phenylsulfones containing a β-hydroxyl stereocenter undergo a diastereoselective isomerization to the corresponding allylic isomer upon treatment with 1,8-diazabicyclo(5.4.0)undec-7-ene (DBU). 

We present measurements of nonlinear Thomson scattering in both emission hemispheres. The asymmetries in these measurements unambiguously confirm for the first time the figure-8 motion of electrons in the average rest frame. 

Effective communication in science is recognized as an important component of training for STEM professionals. This project focuses specifically on improving scientific communication to achieve this goal. Two learning communities that pair STEM research and inquiry activities in biology and chemistry with a public speaking course are being implemented with intentional and sustained instruction and mastery experiences to develop students’ science communication skills. The hypothesis is that instruction on how to communicate science effectively can result in an increase in students' understanding, confidence, and identity as a scientist. This can result in greater student engagement in the major and improved retention in STEM disciplines. Our aim is to test this curriculum intervention to determine its effectiveness in improving student communication ability and achievement. 

A model for antibiotic accumulation in bacterial biofilm microcolonies utilizing heterogenous porosity and attachment site profiles replicated the periphery sequestration reported in prior experimental studies onPseudomonas aeruginosa PAO1biofilm cell clusters. TheseP. aeruginosacell clusters are in vitro models of the chronicP. aeruginosainfections in cystic fibrosis patients which display recalcitrance to antibiotic treatments, leading to exacerbated morbidity and mortality. This resistance has been partially attributed to periphery sequestration, where antibiotics fail to penetrate biofilm cell clusters. The physical phenomena driving this periphery sequestration have not been definitively established. This paper introduces mathematical models to account for two proposed physical phenomena driving periphery sequestration: biofilm matrix attachment and volume-exclusion due to variable biofilm porosity. An antibiotic accumulation model which incorporated these phenomena better fit observed periphery sequestration data compared to previous models. 

Tremendous plant metabolic diversity arises from phylogenetically restricted specialized metabolic pathways. Specialized metabolites are synthesized in dedicated cells or tissues, with pathway genes sometimes colocalizing in biosynthetic gene clusters (BGCs). However, the mechanisms by which spatial expression patterns arise and the role of BGCs in pathway evolution remain underappreciated. In this study, we investigated the mechanisms driving acylsugar evolution in the Solanaceae. Previously thought to be restricted to glandular trichomes, acylsugars were recently found in cultivated tomato roots. We demonstrated that acylsugars in cultivated tomato roots and trichomes have different sugar cores, identified root-enriched paralogs of trichome acylsugar pathway genes, and characterized a key paralog required for root acylsugar biosynthesis,SlASAT1-LIKE(SlASAT1-L), which is nested within a previously reported trichome acylsugar BGC. Last, we provided evidence thatASAT1-Larose through duplication of its paralog,ASAT1, and was trichome-expressed before acquiring root-specific expression in theSolanumgenus. Our results illuminate the genomic context and molecular mechanisms underpinning metabolic diversity in plants. 

We present measurements of nonlinear Thomson scattering out the side of an intense laser focus, showing how subtle defects in laser field including spatial chirp imprint on the angular distribution of the scattered light.