268 research outputs found

    Small and mighty: adaptation of superphylum Patescibacteria to groundwater environment drives their genome simplicity.

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    BackgroundThe newly defined superphylum Patescibacteria such as Parcubacteria (OD1) and Microgenomates (OP11) has been found to be prevalent in groundwater, sediment, lake, and other aquifer environments. Recently increasing attention has been paid to this diverse superphylum including > 20 candidate phyla (a large part of the candidate phylum radiation, CPR) because it refreshed our view of the tree of life. However, adaptive traits contributing to its prevalence are still not well known.ResultsHere, we investigated the genomic features and metabolic pathways of Patescibacteria in groundwater through genome-resolved metagenomics analysis of > 600 Gbp sequence data. We observed that, while the members of Patescibacteria have reduced genomes (~ 1 Mbp) exclusively, functions essential to growth and reproduction such as genetic information processing were retained. Surprisingly, they have sharply reduced redundant and nonessential functions, including specific metabolic activities and stress response systems. The Patescibacteria have ultra-small cells and simplified membrane structures, including flagellar assembly, transporters, and two-component systems. Despite the lack of CRISPR viral defense, the bacteria may evade predation through deletion of common membrane phage receptors and other alternative strategies, which may explain the low representation of prophage proteins in their genomes and lack of CRISPR. By establishing the linkages between bacterial features and the groundwater environmental conditions, our results provide important insights into the functions and evolution of this CPR group.ConclusionsWe found that Patescibacteria has streamlined many functions while acquiring advantages such as avoiding phage invasion, to adapt to the groundwater environment. The unique features of small genome size, ultra-small cell size, and lacking CRISPR of this large lineage are bringing new understandings on life of Bacteria. Our results provide important insights into the mechanisms for adaptation of the superphylum in the groundwater environments, and demonstrate a case where less is more, and small is mighty

    Entrepreneurs' exit and paths to retirement : theoretical and empirical considerations

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    The number of ageing entrepreneurs in micro- and small-sized companies is rapidly increasing in Finland and other European Union countries. Over half a million jobs, in over one hundred thousand companies within the EU, are lost annually due to unsuccessful, predominantly retirement-related transfers of businesses. This challenge coincides with EU Grand Challenges and has been highlighted in the Entrepreneurship 2020 Action Plan (European Commission 2013). It has been estimated that in Finland, some 8000 jobs are lost yearly due to the ageing of entrepreneurs. Therefore, entrepreneur ageing has implications not only for the ageing individual but also for the company and the society at large. As entrepreneurs age it becomes more essential for them to start planning when and how they transition into retirement. While they may experience several exits and subsequent re-entries into working life via buying or starting new companies, exiting ones entrepreneurial career due to old age retirement differs from exits that occur earlier during the career. In this chapter, we provide a short overview of the entrepreneur retirement and exit literature from an age perspective. Furthermore, we present a theoretical conceptualization which combines entrepreneur retirement process with exit theories. This will enable scholars to better understand the retirement process, including decision-making, transitioning, and adjustment to retirement. We also provide empirical evidence using data collected among Finnish entrepreneurs in 2012 and 2015, where we outline the types of exits and assess several factors, including age, in association with exit intentions.fi=vertaisarvioitu|en=peerReviewed

    Spiral and Interlocking Grain in Eucalyptus Dunnii

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    Spiral grain in 181 trees from a 9-year-old plantation-grown Eucalyptus dunnii was normally distributed with mean 0.33 degrees (to the left) and standard deviation 1.7 degrees, and was affected by family and by crown asymmetry. Interlocking grain was common, exhibiting a mean amplitude of 3.4 degrees (standard deviation 1.5 degrees) and a mean wavelength of 39 mm (standard deviation 12 mm). The relatively large amplitude of interlocking grain means that most trees will have spiral grain that alternates between left and right during each year. The wavelength of interlocking grain is influenced by tree size, but amplitude of interlocking is under genetic control. Both spiral grain and the amplitude of any interlocking were heritable (h2 = 0.99 and 0.63 respectively)

    Different expressions of the same mode: a recent dialogue between archaeological and contemporary drawing practices

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    In this article we explore what we perceive as pertinent features of shared experience at the excavations of an Iron Age Hillfort at Bodfari, North Wales, referencing artist, archaeologist and examples of seminal art works and archaeological records resulting through inter-disciplinary collaboration. We explore ways along which archaeological and artistic practices of improvisation become entangled and productive through their different modes of mark-making. We contend that marks and memories of artist and archaeologist alike emerge interactively, through the mutually constituting effects of the object of study, the tools of exploration, and the practitioners themselves, when they are enmeshed in the cross-modally bound activities. These include, but are not limited to, remote sensing, surveying, mattocking, trowelling, drawing, photographing, videoing and sound recording. These marks represent the co-signatories: the gesture of the often anonymous practitioners, the voice of the deposits, as well as the imprint of the tools, and their interplay creates a multi-threaded narrative documenting their modes of intra-action, in short our practices. They occupy the conceptual space of paradata, and in the process of saturating the interstices of digital cognitive prosthetics they lend probity to their translations in both art form and archive

    Business angel exits: A theory of planned behaviour perspective

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    Although there are a handful of studies on business angel investment returns, the business angel literature has given little or no attention to exits and the exit strategy. This is surprising given that a primary objective of investing is to achieve a capital gain through some form of liquidity event. Using the theory of planned behaviour (TPB) as an interpretative heuristic, we examine how exits happen: specifically, what are the motivations to seek an exit and to what extent are they planned or opportunistic? Based on multiple case studies in which business angels were invited to tell the story of their most recent exit(s), the evidence suggests that the majority of liquidity events are the outcome of planned behaviour. We propose a typology of angel-backed investment exits as the basis for identifying future directions for research and developing practical advice to angels on effective business practices

    The impact of digital start-up founders’ higher education on reaching equity investment milestones

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    This paper builds on human capital theory to assess the importance of formal education among graduate entrepreneurs. Using a sample of 4.953 digital start-ups the paper evaluates the impact of start-up founding teams’ higher education on the probability of securing equity investment and subsequent exit for investors. The main findings are: (1), teams with a founder that has a technical education are less likely to remain self-financed and are more likely to secure equity investment and to exit, but the impact of technical education declines with higher level degrees, (2) teams with a founder that has doctoral level business education are less likely to remain self-financed and have a higher probability of securing equity investment, while undergraduate and postgraduate business education have no significant effect, and (3) teams with a founder that has an undergraduate general education (arts and humanities) are less likely to remain self-financed and are more likely to secure equity investment and exit while postgraduate and doctoral general education have no significant effect on securing equity investment and exit. The findings enhance our understanding of factors that influence digital start-ups achieving equity milestones by showing the heterogeneous influence of different types of higher education, and therefore human capital, on new ventures achieving equity milestones. The results suggest that researchers and policy-makers should extend their consideration of universities entrepreneurial activity to include the development of human capital

    Entrepreneurs’ achieved success: developing a multi-faceted measure

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    Firm performance is typically measured via objective financial indicators. However, researchers increasingly acknowledge that entrepreneurs do not measure their success solely in financial terms but that a range of often subjective indicators matter to them. This article contributes to the debate on entrepreneurial performance by studying how entrepreneurs assess their achieved success. ‘Entrepreneurs’ achieved success’ was conceptualized as a multi-faceted construct that includes entrepreneurs’ self-reported achievement of firm performance, workplace relationships, personal fulfilment, community impact, and personal financial rewards. It was measured via the Subjective Entrepreneurial Success–Achievement Scale (SES-AS). Over the course of three studies (N = 390) the factorial structure of ‘entrepreneurs’ achieved success’ was established and largely replicated in two cultures. Based on a nomological network, we documented relationships among ‘entrepreneurs’ achieved success’, quasi-objective indicators of firm performance, and entrepreneurs’ financial satisfaction, creativity, and health. Based on our research, we propose a new conceptual framework to study performance in the context of entrepreneurship. This framework acknowledges both the success criteria that entrepreneurs wish to achieve and those that they actually achieve, and extends our understanding of firm performance
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