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Abstract The visual modality is central to both reception and expression of human creativity. Creativity assessment paradigms, such as structured drawing tasks Barbot (2018), seek to characterize this key modality of creative ideation. However, visual creativity assessment paradigms often rely on cohorts of expert or naïve raters to gauge the level of creativity of the outputs. This comes at the cost of substantial human investment in both time and labor. To address these issues, recent work has leveraged the power of machine learning techniques to automatically extract creativity scores in the verbal domain (e.g., SemDis; Beaty & Johnson 2021). Yet, a comparably well-vetted solution for the assessment of visual creativity is missing. Here, we introduce AuDrA – an Automated Drawing Assessment platform to extract visual creativity scores from simple drawing productions. Using a collection of line drawings and human creativity ratings, we trained AuDrA and tested its generalizability to untrained drawing sets, raters, and tasks. Across four datasets, nearly 60 raters, and over 13,000 drawings, we found AuDrA scores to be highly correlated with human creativity ratings for new drawings on the same drawing task (r= .65 to .81; mean = .76). Importantly, correlations between AuDrA scores and human raters surpassed those between drawings’ elaboration (i.e., ink on the page) and human creativity raters, suggesting that AuDrA is sensitive to features of drawings beyond simple degree of complexity. We discuss future directions, limitations, and link the trained AuDrA model and a tutorial (https://osf.io/kqn9v/) to enable researchers to efficiently assess new drawings. 

Animal cytoplasmic fatty acid synthase (FAS) represents a unique family of enzymes that are classically thought to be most closely related to fungal polyketide synthase (PKS). Recently, a widespread family of animal lipid metabolic enzymes has been described that bridges the gap between these two ubiquitous and important enzyme classes: the animal FAS–like PKSs (AFPKs). Although very similar in sequence to FAS enzymes that produce saturated lipids widely found in animals, AFPKs instead produce structurally diverse compounds that resemble bioactive polyketides. Little is known about the factors that bridge lipid and polyketide synthesis in the animals. Here, we describe the function of EcPKS2 fromElysia chlorotica, which synthesizes a complex polypropionate natural product found in this mollusc. EcPKS2 starter unit promiscuity potentially explains the high diversity of polyketides found in and among molluscan species. Biochemical comparison of EcPKS2 with the previously described EcPKS1 reveals molecular principles governing substrate selectivity that should apply to related enzymes encoded within the genomes of photosynthetic gastropods. Hybridization experiments combining EcPKS1 and EcPKS2 demonstrate the interactions between the ketoreductase and ketosynthase domains in governing the product outcomes. Overall, these findings enable an understanding of the molecular principles of structural diversity underlying the many molluscan polyketides likely produced by the diverse AFPK enzyme family. 

Nitrogen-vacancy (NV) centers in diamond are a promising platform for nanoscale NMR sensing. Despite significant progress toward using NV centers to detect and localize nuclear spins down to the single spin level, NV-based spectroscopy of individual, intact, arbitrary target molecules remains elusive. Such sensing requires that target molecules are immobilized within nanometers of NV centers with long spin coherence. The inert nature of diamond typically requires harsh functionalization techniques such as thermal annealing or plasma processing, limiting the scope of functional groups that can be attached to the surface. Solution-phase chemical methods can be readily generalized to install diverse functional groups, but they have not been widely explored for single-crystal diamond surfaces. Moreover, realizing shallow NV centers with long spin coherence times requires highly ordered single-crystal surfaces, and solution-phase functionalization has not yet been shown with such demanding conditions. In this work, we report a versatile strategy to directly functionalize C–H bonds on single-crystal diamond surfaces under ambient conditions using visible light, forming C–F, C–Cl, C–S, and C–N bonds at the surface. This method is compatible with NV centers within 10 nm of the surface with spin coherence times comparable to the state of the art. As a proof-of-principle demonstration, we use shallow ensembles of NV centers to detect nuclear spins from surface-bound functional groups. Our approach to surface functionalization opens the door to deploying NV centers as a tool for chemical sensing and single-molecule spectroscopy. 

Sex-dependent programs in the liver establish a trade-off between infectious and dietary pressures in mice. 

Transcription factors are proteins that recognize specific DNA sequences and affect local transcriptional processes. They are the primary means by which all organisms control specific gene expression. Understanding which DNA sequences a particular transcription factor recognizes provides important clues into the set of genes that they regulate and, through this, their potential biological functions. Insights may be gained through homology searches and genetic means. However, these approaches can be misleading, especially when comparing distantly related organisms or in cases of complicated transcriptional regulation. In this work, we used a biochemistry-based approach to determine the spectrum of DNA sequences specifically bound by the Thermus thermophilus HB8 TetR-family transcription factor TTHB023. The consensus sequence 5′–(a/c)Y(g/t)A(A/C)YGryCR(g/t)T(c/a)R(g/t)–3′ was found to have a nanomolar binding affinity with TTHB023. Analyzing the T. thermophilus HB8 genome, several TTHB023 consensus binding sites were mapped to the promoters of genes involved in fatty acid biosynthesis. Notably, some of these were not identified previously through genetic approaches, ostensibly given their potential co-regulation by the Thermus thermophilus HB8 TetR-family transcriptional repressor TTHA0167. Our investigation provides additional evidence supporting the usefulness of a biochemistry-based approach for characterizing putative transcription factors, especially in the case of cooperative regulation. 

Short DNA probes, for example, those used in characterizing protein-DNA complexes, have historically been radiolabeled with 32P to allow their detection and quantitation following native polyacrylamide gel electrophoresis (PAGE). For reasons of economy or safety, alternative means of DNA detection need to be used. Described here is the resolution of 5' IRD700 and IRD800 end-labeled DNAs by native PAGE and their visualization and quantitation by IR fluorescence imaging. 

Protein-DNA binding interactions are critical in several biological processes, especially the regulation of gene expression at the level of transcription initiation. An important technique for studying these interactions is the electrophoretic mobility shift assay (EMSA), whereby protein-DNA complexes are resolved on the basis of their mass:charge ratio using native polyacrylamide gel electrophoresis (nPAGE). Here we describe EMSA using PCR-generated, near infrared-fluorescent DNA probes, and IR fluorescence imaging to qualitatively and quantitatively study the interaction of transcriptional regulatory proteins from thermophilic organisms with different DNAs. Direct imaging of IR fluorophore-labeled DNA probes is advantageous because it provides high sensitivity (subnanomolar) without the need for intermediate staining steps or costly and problematic radiolabeled probes, thereby providing a more affordable and sensitive option to image protein-DNA on polyacrylamide gels by techniques such as EMSA. 

Advances in genomic sequencing have allowed the identification of a multitude of genes encoding putative transcriptional regulatory proteins. Lacking, often, is a fuller understanding of the biological roles played by these proteins, the genes they regulate or regulon. Conventionally this is achieved through a genetic approach involving putative transcription factor gene manipulation and observations of changes in an organism’s transcriptome. However, such an approach is not always feasible or can yield misleading findings. Here, we describe a biochemistry-centric approach, involving identification of preferred DNA-binding sequences for the Thermus thermophilus HB8 transcriptional repressor TTHA0973 using the selection method Restriction Endonuclease Protection, Selection and Amplification (REPSA), massively parallel sequencing, and bioinformatic analyses. We identified a consensus TTHA0973 recognition sequence of 5′–AACnAACGTTnGTT–3′ that exhibited nanomolar binding affinity. This sequence was mapped to several sites within the T. thermophilus HB8 genome, a subset of which corresponded to promoter regions regulating genes involved in phenylacetic acid degradation. These studies further demonstrate the utility of a biochemistry-centric approach for the facile identification of potential biological functions for orphan transcription factors in a variety of organisms. 

A mass spectrometry and dialysis method detects metabolite-protein interactions that help to control physiology. 

We report an experiment on payoff‐equivalent, sequential provision and appropriation games with high‐ and low‐caste Indian villagers. A central question is whether caste identities affect resolution of social dilemmas. Making caste salient elicits striking changes in behavior compared to baseline treatment with no information about others' castes. Homogenous groups with high caste villagers are more successful in resolving social dilemmas than homogenous groups with low caste villagers. The success of mixed‐caste groups is somewhere between, which is inconsistent with a group identity model. Absent salient information on caste, behavior is inconsistent with unconditional social preferences but as predicted by reciprocity. (JELC93, H41, Z13)