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Arnold Toynbee's lectures on the Industrial Revolution (published in 1884) were the first-and the most influential-attempt to historicize Britain's radical transition to a machine-based economy. This article locates the lectures in the context of the increasing disciplinary specialization of late-nineteenth-century Britain. Toynbee's intellectual character and political commitments shaped an approach to the machinery question which was holist and thus placed him at odds with emerging specialists in history and economics. Despite various shortcomings, the lectures suggest the generative potential of the machinery question for an integrated economic and historical science, at which Toynbee's unfinished work only hinted. [ABSTRACT FROM AUTHOR]

A whole-genome sequencing technique developed to identify fast neutron-induced deletion mutations revealed that iap1-1 is a new allele of EDS5 (eds5-5). RPS2-AvrRpt2-initiated effector-triggered immunity (ETI) was compromised in iap1-1/eds5-5 with respect to in planta bacterial levels and the hypersensitive response, while intra- and intercellular free salicylic acid (SA) accumulation was greatly reduced, suggesting that SA contributes as both an intracellular signaling molecule and an antimicrobial agent in the intercellular space during ETI. During the compatible interaction between wild-type Col-0 and virulent Pseudomonas syringae pv. tomato (Pst), little intercellular free SA accumulated, which led to the hypothesis that Pst suppresses intercellular SA accumulation. When Col-0 was inoculated with a coronatine-deficient strain of Pst, high levels of intercellular SA accumulation were observed, suggesting that Pst suppresses intercellular SA accumulation using its phytotoxin coronatine. This work suggests that accumulation of SA in the intercellular space is an important component of basal/PAMP-triggered immunity as well as ETI to pathogens that colonize the intercellular space. [ABSTRACT FROM AUTHOR]

This article introduces the 'Environmental Scan' as answer to the question of hidden biases in digital heritage collections. Its substantive focus is digitized nineteenth-century British provincial newspapers, and in particular the JISC corpus, a popular, publicly-funded resource for scholars. While multiple papers have meticulously investigated the genesis of such newspaper collections, in the process highlighting the often unacknowledged politics of collection, preservation and dissemination via microfilm and now digitization, our aim is to explore questions of representativeness and bias in new ways by enriching computational analysis of digital corpora with the historical insights that can be derived from a contemporaneous reference source: namely, the Victorian newspaper press directories. [ABSTRACT FROM AUTHOR]

The lipid transfer protein (LTP) DEFECTIVE IN INDUCED RESISTANCE1 (DIR1) is a key mobile component of the systemic acquired resistance (SAR) response. Recent evidence suggests that a DIR1-like paralog occasionally compensates for the loss of DIR1 in the dir1-1 Ws-2 mutant. Here, we demonstrate that a dir1-2 mutant in the Col-0 background is SAR-defective, while DIR1-like knockdowns are SAR-competent. Moreover, protein-protein interaction assays demonstrate that DIR1 interacts with DIR1-like and other LTPs. Further investigation of these LTPs suggests a role for LTP2 in SAR. Our results highlight the importance of multiple lipid transfer proteins for SAR in Arabidopsis . [ABSTRACT FROM AUTHOR]

Systemic acquired resistance (SAR) is a plant defense response that provides long-lasting, broad-spectrum pathogen resistance to uninfected systemic leaves following an initial localized infection. In Arabidopsis (Arabidopsis thaliana), local infection with virulent or avirulent strains of Pseudomonas syringae pv tomato generates long-distance SAR signals that travel from locally infected to distant leaves through the phloem to establish SAR. In this study, a proteomics approach was used to identify proteins that accumulate in phloem exudates in response to the induction of SAR. To accomplish this, phloem exudates collected from mock-inoculated or SAR-induced leaves of wild-type Columbia-0 plants were subjected to label-free quantitative liquid chromatography-tandem mass spectrometry proteomics. Comparing mock- and SAR-induced phloem exudate proteomes, 16 proteins were enriched in phloem exudates collected from SAR-induced plants, while 46 proteins were suppressed. SAR-related proteins THIOREDOXIN h3, ACYL-COENZYME A-BINDING PROTEIN6, and PATHOGENESIS-RELATED1 were enriched in phloem exudates of SAR-induced plants, demonstrating the strength of this approach and suggesting a role for these proteins in the phloem during SAR. To identify novel components of SAR, transfer DNA mutants of differentially abundant phloem proteins were assayed for SAR competence. This analysis identified a number of new proteins (m-type thioredoxins, major latex protein-like protein, ULTRAVIOLET-B RESISTANCE8 photoreceptor) that contribute to the SAR response. The Arabidopsis SAR phloem proteome is a valuable resource for understanding SAR long-distance signaling and the dynamic nature of the phloem during plant-pathogen interactions. [ABSTRACT FROM AUTHOR]

Although the Ordnance Survey has itself been the subject of historical research, scholars have not systematically used its maps as primary sources of information. This is partly for disciplinary reasons and partly for the technical reason that high-quality maps have not until recently been available digitally, geo-referenced, and in color. A final, and crucial, addition has been the creation of item-level metadata which allows map collections to become corpora which can for the first time be interrogated en masse as source material. By applying new Computer Vision methods leveraging machine learning, we outline a research pipeline for working with thousands (rather than a handful) of maps at once, which enables new forms of historical inquiry based on spatial analysis. Our 'patchwork method' draws on the longstanding desire to adopt an overall or 'complete' view of a territory, and in so doing highlights certain parallels between the situation faced by today's users of digitized maps, and a similar inflexion point faced by their predecessors in the nineteenth century, as the project to map the nation approached a form of completion. [ABSTRACT FROM AUTHOR]

The leaf intercellular space is a site of plant-microbe interactions where pathogenic bacteria such as Pseudomonas syringae grow. In Arabidopsis thaliana, the biosynthesis of tryptophan-derived indolic metabolites is induced by P. syringae infection. Using high-resolution mass spectrometry-based profiling and biosynthetic mutants, we investigated the role of indolic compounds and other small molecules in the response of mature Arabidopsis to P. syringae. We observed dihydrocamalexic acid (DHCA), the precursor to the defense-related compound camalexin, accumulating in intercellular washing fluids (IWFs) without further conversion to camalexin. The indolic biosynthesis mutant cyp71a12/cyp71a13 was more susceptible to P. syringae compared to mature wild-type plants displaying age-related resistance (ARR). DHCA and structural analogs inhibit P. syringae growth (MIC ~ 500 μg/mL), but not at concentrations found in IWFs, and DHCA did not inhibit biofilm formation in vitro. However, infiltration of exogenous DHCA enhanced resistance in mature cyp71a12/cyp71a13. These results provide evidence that DHCA derived from CYP71A12 and CYP71A13 activity accumulates in the intercellular space and contributes to the resistance of mature Arabidopsis to P. syringae without directly inhibiting bacterial growth. [Display omitted] • CYP71A12/A13-derived DHCA accumulates in the leaf intercellular space in response to P. syringae. • Mature cyp71a12/a13 plants are (deficient in intercellular DHCA) is more susceptible to P. syringae. • Exogenous DHCA applied to cyp71a12/a13 enhances resistance to P. syringae. [ABSTRACT FROM AUTHOR]