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Summary Plant homeodomain leucine zipper IV (HD‐Zip IV) transcription factors (TFs) contain an evolutionarily conserved steroidogenic acute regulatory protein (StAR)‐related lipid transfer (START) domain. While the START domain is required for TF activity, its presumed role as a lipid sensor is not clear.Here we used tandem affinity purification fromArabidopsiscell cultures to demonstrate that PROTODERMAL FACTOR2 (PDF2), a representative member that controls epidermal differentiation, recruits lysophosphatidylcholines (LysoPCs) in a START‐dependent manner. Microscale thermophoresis assays confirmed that a missense mutation in a predicted ligand contact site reduces lysophospholipid binding.We additionally found that PDF2 acts as a transcriptional regulator of phospholipid‐ and phosphate (Pi) starvation‐related genes and binds to a palindromic octamer with consensus to a Pi response element. Phospholipid homeostasis and elongation growth were altered inpdf2mutants according to Pi availability. Cycloheximide chase experiments revealed a role for START in maintaining protein levels, and Pi starvation resulted in enhanced protein destabilization, suggesting a mechanism by which lipid binding controls TF activity.We propose that the START domain serves as a molecular sensor for membrane phospholipid status in the epidermis. Our data provide insights toward understanding how the lipid metabolome integrates Pi availability with gene expression. 

The cyto- and genotoxic potencies of disinfection by-products (DBPs) have been evaluated in published literature by measuring the response of exposed Chinese hamster ovary cells. In recent publications, DBP concentrations divided by their individual toxicity indices are summed to predict the relative toxicity of a water sample. We hypothesized that the omission or inclusion of certain DBPs over others is equivalent to statistical sampling bias and may result in biased conclusions. To test this hypothesis, we removed or added actual or simulated DBP measurements to that of published studies which evaluated granular activated carbon as a treatment to reduce the relative toxicity of the effluent. In several examples, it was possible to overturn the conclusions ( i.e. , activated carbon is detrimental or beneficial in reducing toxicity) by preferentially including specific DBPs. In one example, removing measured haloacetaldehydes caused the predicted cytotoxicity of a treated sample to decrease by up to 47%, reversing the initial conclusion that activated carbon increased the toxicity of the water. We also discuss measurements of statistical error, which are rarely included in publications related to predicted toxicity, but strongly influence the outcomes. Finally, we discuss future research needs in the light of these and other concerns. 

This research paper elaborates on the process used by a team of researchers to create a codebook from interviews of Civil Engineers who included students, professors, and professionals, solving ill-structured problems. The participants solved two ill-structured problems while speaking aloud their thought process. In addition to recording the participant verbalization, the solution to their problems were also collected with the use of a smart pen. Creating a codebook from interviews is a key element of qualitative analysis forming the basis for coding. While individuals can create codebooks for analysis, a team-based approach is advantageous especially when dealing with large amounts of data. A team-based approach involves an iterative process of inter-rater reliability essential to the trustworthiness of the data obtained by coding. In addition to coding the transcripts as a team, which consisted of novice, intermediate, and experts in the engineering education field, the audio and written solution to the problems were also coded. The use of multiple data sources to obtain data, and not just the verbatim transcripts, is lesser studied in engineering education literature and provides opportunities for a more detailed qualitative analysis. Initial codes were created from existing literature, which were refined through an iterative process. This process consisted of coding data, team consensus on coded data, codebook refinement, and recoding data with the refined codes. Results show that coding verbatim transcripts might not provide an accurate representation of the problem-solving processes participants used to solve the ill-structured problem. Benefits, challenges and recommendations regarding the use of multiple sources to obtain data are discussed while considering the amount of time required to conduct such analysis.