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Premise of Study In a seminal body of theory, Lloyd showed that the fitness consequences of selfing will depend on its timing in anthesis. Selfing that occurs after opportunities for outcrossing or pollen dispersal can provide reproductive assurance when pollinators are limited and is expected to incur little cost, even when inbreeding depression is high. As a result, delayed selfing is often interpreted as a “best‐of‐both‐worlds” mating system that combines the advantages of selfing and outcrossing. Methods We surveyed 65 empirical studies of delayed selfing, recording floral mechanisms and examining information on inbreeding depression, autofertility, and other parameters to test the support for delayed selfing as a best‐of‐both‐worlds strategy. Key Results Phylogenetic distribution of the diverse floral mechanisms suggests that some basic floral structures may predispose plant taxa to evolve delayed selfing. Delayed selfing appears to serve as a best‐of‐both‐worlds strategy in some but not all species. While the capacity for autonomous selfing is often high, it is lower, in some cases, than in related species with earlier modes of selfing. In other delayed‐selfers, low inbreeding depression and reduced investment in corollas and pollen suggest limited benefits from outcrossing. Conclusions Despite a growing literature on the subject, experimental evidence for delayed selfing is limited and major gaps in knowledge remain, particularly with respect to the stability of delayed selfing and the conditions that may favor transitions between delayed and earlier selfing. Finally, we suggest a potential role of delayed selfing in facilitating transitions from self‐incompatibility to selfing.

Anni Albers (1899-1994) was a German textile designer, weaver, and printmaker, and among the leading pioneers of 20th-century modernism. Although she has heavily influenced generations of artists and designers, her contribution to modernist art history has been comparatively overlooked, especially in relation to that of her husband, Josef. In this groundbreaking and beautifully illustrated volume, Albers's most important works are examined to fully explore and redefine her contribution to 20th-century art and design and highlight her significance as an artist in her own right. Featured works--from her early activity at the Bauhaus as well as from her time at Black Mountain College, and spanning her entire fruitful career--include wall hangings, designs for commercial use, drawings and studies, jewelry, and prints. Essays by international experts focus on key works and themes, relate aspects of Albers's practice to her seminal texts On Designing and On Weaving, and identify broader contextual material, including examples of the Andean textiles that Albers collected and in which she found inspiration for her understanding of woven thread as a form of language. Illuminating Albers's skill as a weaver, her material awareness, and her deep understanding of art and design, this publication celebrates an artist of enormous importance and showcases the timeless nature of her creativity.

As climate change progresses, we are observing widespread changes in phenotypes in many plant populations. Whether these phenotypic changes are directly caused by climate change, and whether they result from phenotypic plasticity or evolution, are active areas of investigation. Here, we review terrestrial plant studies addressing these questions. Plastic and evolutionary responses to climate change are clearly occurring. Of the 38 studies that met our criteria for inclusion, all found plastic or evolutionary responses, with 26 studies showing both. These responses, however, may be insufficient to keep pace with climate change, as indicated by eight of 12 studies that examined this directly. There is also mixed evidence for whether evolutionary responses are adaptive, and whether they are directly caused by contemporary climatic changes. We discuss factors that will likely influence the extent of plastic and evolutionary responses, including patterns of environmental changes, species’ life history characteristics including generation time and breeding system, and degree and direction of gene flow. Future studies with standardized methodologies, especially those that use direct approaches assessing responses to climate change over time, and sharing of data through public databases, will facilitate better predictions of the capacity for plant populations to respond to rapid climate change.

Using network representations of the lexicon has expanded our understanding of vocabulary growth processes and vocabulary structure during early development. These models of vocabulary development have used multiple types of sources to create lexical representations. More recently, Weber and Colunga (2022) demonstrated that predictions of early vocabulary norms can be improved by using network representations based on a corpus incorporating language a young child might typically hear. The present work goes a step further by evaluating the accuracy of network representations for predicting individual children's word learning that are based on embeddings that are readily available or embeddings gathered from the same child language corpus. We predicted the specific words that individual children add to their vocabulary over time, using a longitudinal data set of 86 monolingual English-speaking toddler's changing vocabulary from 18 to 30 months of age. The toddler-based network predicted word learning more accurately than the off-the-shelf network. Further, there was an advantage for prediction methods that took into account the individual child's particular network structure rather than overall network connectivity. These results highlight the importance of tailoring representational and processing choices to the population of interest. L'utilisation de représentations en réseau du lexique a permis de mieux comprendre les processus d'enrichissement du vocabulaire et la structure du vocabulaire dans la phase précoce du développement. Ces modèles de développement du vocabulaire ont employé divers types de sources pour créer des représentations lexicales. Plus récemment, Weber et Colunga (2022) ont démontré que les prédictions des normes de vocabulaire précoce peuvent être améliorées en utilisant des représentations en réseau basées sur un corpus incorporant le langage qu'un enfant en bas âge pourrait typiquement entendre. La présente étude va plus loin en évaluant la précision des représentations en réseau pour prédire l'apprentissage de mots chez les enfants, qui sont fondées sur des emboîtements couramment disponibles ou sur des emboîtements recueillis dans le même corpus linguistique d'enfants. Nous avons prédit les mots explicites que les enfants ajoutent à leur vocabulaire au fil du temps, en utilisant un ensemble de données longitudinales de 86 enfants en bas âge monolingues anglophones dont le vocabulaire évolue entre 18 et 30 mois. Le réseau basé sur les enfants en bas âge a prédit l'apprentissage des mots avec plus de précision que le réseau standard. De plus, les méthodes de prédiction tenant compte de la structure spécifique du réseau de l'enfant plutôt que de la connectivité globale du réseau offrent un avantage. Ces résultats soulignent l'importance d'adapter les choix de représentation et de traitement à la population concernée. Public Significance Statement Models of early word learning for individual toddlers are more accurate when they use semantic representations that are more representative of young children's linguistic environment and take into account the structure of the individual toddler's vocabulary. Tailoring representations and processes to specific subpopulations is critical to model different populations of interest, including different age groups and language profiles.

Human mesenchymal stem cells (hMSCs) present an attractive target for cell therapy given their wide availability, immunomodulatory properties, and multipotent nature for differentiation into chondrocytes, osteocytes, and adipocytes. With the progression of hMSC clinical studies, there is an increasing demand for development of technologies that enable efficient cell scale-up into clinically relevant quantities. Commercial scale manufacturing of hMSCs will require a large surface area which is not cost effective with available two-dimensional culture vessels. Recent studies showed that microcarriers provide a three-dimensional culture environment suitable for hMSC expansion. Traditionally, biological coatings and/or serum-containing medium are required to facilitate hMSC attachment and expansion in dynamic conditions. These limitations may hinder the use of microcarriers as a scale-up technology for hMSC therapeutics, where cell products, and therefore patient safety, are more controlled with the use of xeno-free, defined culture conditions. Here we report the long term culture of hMSCs on novel synthetic Synthemax II microcarriers in two different xeno-free media. Cells were maintained over 40 days on sterile, ready-to-use microcarriers in spinner flasks with programmed agitation. hMSC expansion was obtained by addition of fresh beads without the need for enzymatic dissociation. We achieved a cumulative cell expansion of >10,000 fold, and cells retained normal hMSC phenotype, karyotype, and tri-lineage differentiation potential. To our knowledge, this report is the first example of long term culture of hMSCs on synthetic microcarriers in xeno-free, defined conditions.

Human induced pluripotent stem cells have the potential to become an unlimited cell source for cell replacement therapy. The realization of this potential, however, depends on the availability of culture methods that are robust, scalable, and use chemically defined materials. Despite significant advances in hiPSC technologies, the expansion of hiPSCs relies upon the use of animal-derived extracellular matrix extracts, such as Matrigel, which raises safety concerns over the use of these products. In this work, we investigated the feasibility of expanding and differentiating hiPSCs on a chemically defined, xeno-free synthetic peptide substrate, i.e. Corning Synthemax(®) Surface. We demonstrated that the Synthemax Surface supports the attachment, spreading, and proliferation of hiPSCs, as well as hiPSCs' lineage-specific differentiation. hiPSCs colonies grown on Synthemax Surfaces exhibit less spread and more compact morphology compared to cells grown on Matrigel™. The cytoskeleton characterization of hiPSCs grown on the Synthemax Surface revealed formation of denser actin filaments in the cell-cell interface. The down-regulation of vinculin and up-regulation of zyxin expression were also observed in hiPSCs grown on the Synthemax Surface. Further examination of cell-ECM interaction revealed that hiPSCs grown on the Synthemax Surface primarily utilize α(v)β(5) integrins to mediate attachment to the substrate, whereas multiple integrins are involved in cell attachment to Matrigel. Finally, hiPSCs can be maintained undifferentiated on the Synthemax Surface for more than ten passages. These studies provide a novel approach for expansion of hiPSCs using synthetic peptide engineered surface as a substrate to avoid a potential risk of contamination and lot-to-lot variability with animal derived materials.

The development of fully defined culture conditions for human embryonic stem cells (hESCs) should enhance experimental reproducibility, reduce unwanted contaminants and facilitate scale-up production. Melkoumian et al . show that a substrate made of peptides derived from extracellular matrix proteins supports long-term culture of hESCs and differentiation to cardiomyocytes. Human embryonic stem cells (hESCs) have two properties of interest for the development of cell therapies: self-renewal and the potential to differentiate into all major lineages of somatic cells in the human body. Widespread clinical application of hESC-derived cells will require culture methods that are low-cost, robust, scalable and use chemically defined raw materials. Here we describe synthetic peptide-acrylate surfaces (PAS) that support self-renewal of hESCs in chemically defined, xeno-free medium. H1 and H7 hESCs were successfully maintained on PAS for over ten passages. Cell morphology and phenotypic marker expression were similar for cells cultured on PAS or Matrigel. Cells on PAS retained normal karyotype and pluripotency and were able to differentiate to functional cardiomyocytes on PAS. Finally, PAS were scaled up to large culture-vessel formats. Synthetic, xeno-free, scalable surfaces that support the self-renewal and differentiation of hESCs will be useful for both research purposes and development of cell therapies.

Premise Understanding species’ responses to climate change is a critical challenge facing biologists today. Though many species are widespread, few studies of climate‐driven shifts in flowering time have examined large continuous spatial scales for individual species. And even fewer studies have examined these shifts at time scales greater than a few decades. Methods We used digitized herbarium specimens and PRISM climate data to produce the spatially and temporally broadest‐scale study of flowering time in a single species to date, spanning the contiguous United States and 153 years (1863–2016) for a widespread weedy annual, Triodanis perfoliata (Campanulaceae). We examined factors driving phenological shifts as well as the roles of geographic and temporal scale in understanding these trends. Results Year was a significant factor in both geospatial and climatic analyses, revealing that flowering time has advanced by ~9 days over the past ~150 years. We found that temperature as well as vapor pressure deficit, an understudied climatic parameter associated with evapotranspiration and water stress, were strongly associated with peak flowering. We also examined how sampling at different spatiotemporal scales influences the power to detect flowering‐time shifts, finding that relatively large spatial and temporal scales are ideal for detecting flowering‐time shifts in this widespread species. Conclusions Our results emphasize the importance of understanding the interplay of geospatial factors at different scales to examine how species respond to climate change.

Using citizen science resources and projects in university education is a burgeoning pedagogical tool that can promote real-world application of science, autonomous learning, and understanding of self-efficacy in science learning. In this case study, we examined several factors relating to self-efficacy and skill growth in STEM and non-STEM majors in life science courses of different levels at one university. Four life science classes in Fall 2022 (n = 109 students) voluntarily participated in a self-guided pollinator training module. Motivations, previous awareness, participation, and self-efficacy and self-identification for citizen science participation and for general scientific inquiry were assessed through pre- and post-surveys before and after module training. Students characterized themselves as STEM or non-STEM majors to understand self-identity. In having students self-report their identity in STEM, we found a trend (79.2%) of natural resource and agricultural majors ranking themselves as non-STEM. Across all participants, we observed a significant increase for learning outcomes between pre- and post-survey results (ɑ = 0.05). Self-reported non-STEM students showed a positive trend between surveys across survey questions. In comparison, self-reported STEM students showed very little increase across surveys but ranked highly in both pre- and post-survey results (mean = 3.42 out of 4). Overall, our findings suggest that even small-scale citizen science–based projects may increase students’ familiarity with concepts based in scientific inquiry and meet learning outcomes benefitting the goals of both higher education and citizen science initiatives.