95 research outputs found

    A novel technique for reducing soil fertility in ecological restoration projects

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    Surface soil eutrophication hinders ecological restoration projects by favouring communities of low biodiversity. This study assesses the effectiveness of a novel technique known as topsoil inversion that may promote recovery from eutrophication. Topsoil inversion is undertaken by a deep plough, which buries 30 cm of topsoil under approximately 40 cm of subsoil. The main study site is within new community woodland on former agricultural land. It comprises deep ploughed and conventionally ploughed plots, to compare two planting types: wildflowers only, and wildflowers with trees. This presentation will discuss some preliminary findings of the effect of topsoil inversion on soil properties and plant tissue nutrient content. Surface soil fertility is lowered following inversion treatment, and this appears to affect plant nutrient sequestration. These results suggest that topsoil inversion has the potential to facilitate ecological restoration on eutrophic soil. This technique may have benefits for restoration projects taking place in a variety of habitats affected by air pollution, including former agricultural land and lowland heaths

    Crossbow Volume 1

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    Student Integrated ProjectIncludes supplementary materialDistributing naval combat power into many small ships and unmanned air vehicles that capitalize on emerging technology offers a transformational way to think about naval combat in the littorals in the 2020 time frame. Project CROSSBOW is an engineered systems of systems that proposes to use such distributed forces to provide forward presence to gain and maiantain access, to provide sea control, and to project combat power in the littoral regions of the world. Project CROSSBOW is the result of a yearlong, campus-wide, integrated research systems engineering effort involving 40 student researchers and 15 supervising faculty members. This report (Volume I) summarizes the CROSSBOW project. It catalogs the major features of each of the components, and includes by reference a separate volume for each of the major systems (ships, aircraft, and logistics). It also prresents the results of the mission and campaign analysis that informed the trade-offs between these components. It describes certain functions of CROSSBOW in detail through specialized supporting studies. The student work presented here is technologically feasible, integrated and imaginative. The student project cannot by itself provide definitive designs or analyses covering such a broad topic. It does strongly suggest that the underlying concepts have merit and deserve further serious study by the Navy as it transforms itself

    Seeing versus Doing: How Businesses Manage Tensions in Pursuit of Sustainability

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    Management of organizational tensions can facilitate the simultaneous advancement of economic, social, and environmental priorities. The approach is based on managers identifying and managing tensions between the three priorities, by employing one of the three strategic responses. Although recent work has provided a theoretical basis for such tension acknowledgment and management, there is a dearth of empirical studies. We interviewed 32 corporate sustainability managers across 25 forestry and wood-products organizations in Australia. Study participants were divided into two groups: (1) those considered effective at corporate sustainability and (2) a status-quo group. Contrary to current theory, our findings showed that acknowledgment of organizational tensions was widespread in the Australian forestry and wood-products industry and not limited to those managers who are effective at managing corporate sustainability. What differed was the degree to which managers did something about the perceived tensions—with the effective group more consistently acting to manage and resolve paradoxical scenarios. Our findings suggest that existing theoretical constructs of tension management may not adequately capture the individual-level complexity involved with managing tensions in practice

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Organizational Evolution with Fuzzy Technological Boundaries: Tape Drive Producers in the World Market, 1951-1998

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    We study how tape drive producers respond to the almost continuous emergence of new drive formats across the technology's history. The analysis characterizes the technological formats of tape drives according to their degree of contrast (distinctiveness and visibility) from other formats. High contrast implies strong boundaries, which prevent information leakage and appear to provide solid strategic footing because they are not easy to adopt and replicate; yet formats with strong boundaries may appear risky to potential customers who may prefer formats more readily substitutable. We develop and test arguments about how different types of tape drive manufacturers add and drop the production of formats as a function of the contrast of formats. A key distinction we make is between single-format producers whose format has high contrast (yielding a clear firm level identity) and multi-format producers whose various formats blur the firm's identity when they are high in contrast. In the empirical analysis, we find that single-format firms producing formats with high contrast experience a lower rate of mortality, while average high contrast in the technology portfolio of multi-format producers lowers their survival chances. We also find that single-format firms with technology formats characterized by high levels of contrast are: (1) more likely to add newly emerging formats and (2) less likely to drop existing formats. By contrast, multi-format manufacturers show mixed patterns.

    Gender differences in academic productivity and academic career choice among urology residents.

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    PurposeGender disparities have long existed in medicine but they have not been well examined in urology. We analyzed a large cohort of graduating urology residents to investigate gender disparities in academic productivity, as measured by peer reviewed publications and academic career choice.Materials and methodsWe assembled a list of urology residents who graduated from 2002 through 2008 who were affiliated with the top 50 urology hospitals, as ranked by 2009 U.S. News & World Report. PubMed® was queried to determine the publication output of each resident during the last 3 years of residency. We used an Internet search to determine the fellowship training, career choice and academic rank of each subject. Gender effects on each factor were evaluated.ResultsA total of 459 male (84.5%) and 84 female (15.5%) residents were included in analysis. During residency women produced fewer total publications (average 3.0 vs 4.8, p = 0.01) and fewer as first author (average 1.8 vs 2.5, p = 0.03) than men. A higher proportion of women than men underwent fellowship training (54.8% vs 48.5%, p = 0.29) and ultimately chose an academic career (40.5% vs 33.3%, p = 0.20), although these differences were not statistically significant. Of residents who chose an academic career a higher proportion of men than women (24.7% vs 2.9%, p = 0.01) obtained associate vs assistant professor rank.ConclusionsWomen produced fewer peer reviewed publications than men during residency but they were equally likely to undergo fellowship training and choose an academic career. During the study period a higher proportion of men achieved associate professor rank
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