252 research outputs found

    Generalizing the GAGA Principle

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    This paper generalizes the fundamental GAGA results of Serre cite{MR0082175} in three ways---to the non-separated setting, to stacks, and to families. As an application of these results, we show that analytic compactifications of Mg,n\mathcal{M}_{g,n} possessing modular interpretations are algebraizable.Comment: 19 page

    Report on Interstate 476 (The Blue Route)

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    For fifty years Pennsylvanians have been discussing the idea of constructing a new north-south highway in the central part of Delaware County, the suburban county immediately west of the City of Philadelphia. Such a highway originally was conceived as a parkway. The notion never got very far until the mid-1950\u27s. When the federal Interstate Highway System was conceived, a facility in central Delaware County was proposed to connect the Pennsylvania Turnpike (I-276) in Plymouth Meeting, Montgomery County, with the Delaware Expressway (I-95) in Ridley Township, Delaware County. This facility was designated I-476. As conceived, it would constitute the western part of a planned circumferential freeway network around Philadelphia. I-476 is commonly known as the Blue Route and also as the Mid County Expressway. As an interstate highway project, 90% of the cost of I-476 would be covered by federal interstate highway funds allocated to the Pennsylvania Department of Transportation (PennDOT) by the Federal Highway Administration (FHWA). The remaining 10% of the project\u27s cost would be paid for by PennDOT (either construction bonds or revenues from the State Motor Fund). Construction of the Blue Route commenced in 1967 but all con­struction on the main stretch of the road--the 16.9 mile section be­ tween I-95 and the Schuylkill Expressway (I-76)--was halted in 1973. Construction of this portion cannot resume until the project undergoes an environmental impact assessment under the provisions of federal law. The project also must undergo a so-called 4(f) assessment analyzing the facility\u27s impact on parkland and historical resources. The requirements of these federal statutes are summarized in an appen­dix to this report. Because of the uncertainty surrounding completion of the Blue Route, and because the project has aroused considerable controversy in Delaware County, U.S. Representative Robert W. Edgar in March 1977 organized a Transportation Advisory Committee to un­dertake a comprehensive analysis of the project. [...] This report is submitted to the Congressman as the Committee\u27s recommendation

    Transport of sulfur dioxide from the Asian Pacific Rim to the North Pacific troposphere

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    The NASA Pacific Exploratory Mission over the Western Pacific Ocean (PEM-West B) field experiment provided an opportunity to study sulfur dioxide (SO2) in the troposphere over the western Pacific Ocean from the tropics to 60°N during February–March 1993. The large suite of chemical and physical measurements yielded a complex matrix in which to understand the distribution of sulfur dioxide over the western Pacific region. In contrast to the late summer period of Pacific Exploratory Mission-West A (PEM-West A) (1991) over this same area, SO2showed little increase with altitude, and concentrations were much lower in the free troposphere than during the PEM-West B period. Volcanic impacts on the upper troposphere were again found as a result of deep convection in the tropics. Extensive emission of SO2 from the Pacific Rim land masses were primarily observed in the lower well-mixed part of the boundary layer but also in the upper part of the boundary layer. Analyses of the SO2 data with aerosol sulfate, beryllium-7, and lead-210 indicated that SO2 contributed to half or more of the observed total oxidized sulfur (SO2 plus aerosol sulfate) in free tropospheric air. The combined data set suggests that SO2 above 8.5 km is transported from the surface but with aerosol sulfate being removed more effectively than SO2. Cloud processing and rain appeared to be responsible for lower SO2 levels between 3 and 8.5 km than above or below this region

    Do changes in current flow as a result of arrays of tidal turbines have an effect on benthic communities?

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    Arrays of tidal energy converters have the potential to provide clean renewable energy for future generations. Benthic communities may, however, be affected by changes in current speeds resulting from arrays of tidal converters located in areas characterised by strong currents. Current speed, together with bottom type and depth, strongly influence benthic community distributions; however the interaction of these factors in controlling benthic dynamics in high energy environments is poorly understood. The Strangford Lough Narrows, the location of SeaGen, the world's first single full-scale, grid-compliant tidal energy extractor, is characterised by spatially heterogenous high current flows. A hydrodynamic model was used to select a range of benthic community study sites that had median flow velocities between 1.5-2.4 m/s in a depth range of 25-30 m. 25 sites were sampled for macrobenthic community structure using drop down video survey to test the sensitivity of the distribution of benthic communities to changes in the flow field. A diverse range of species were recorded which were consistent with those for high current flow environments and corresponding to very tide-swept faunal communities in the EUNIS classification. However, over the velocity range investigated, no changes in benthic communities were observed. This suggested that the high physical disturbance associated with the high current flows in the Strangford Narrows reflected the opportunistic nature of the benthic species present with individuals being continuously and randomly affected by turbulent forces and physical damage. It is concluded that during operation, the removal of energy by marine tidal energy arrays in the far-field is unlikely to have a significant effect on benthic communities in high flow environments. The results are of major significance to developers and regulators in the tidal energy industry when considering the environmental impacts for site licences. 2016 Kregting et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The work was funded by through a Technology Strategy Board (TSB) funded project (TS10023231/1901), awarded to Graham Savidge and UK Engineering and Physical Science Research Council funding agreement (grant number EP/J010065/1), awarded to Bjoern Elsaesser. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The work was funded by through a Technology Strategy Board (TSB) funded project (TS10023231/1901), awarded to Graham Savidge and UK Engineering and Physical Science Research Council funding agreement (grant number EP/J010065/1), awarded to Bjoern Elsaesser.Scopu

    A program and project management approach for collaborative university-industry R&D funded contracts

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    This paper presents a new program and project management (PPM) approach especially devoted to support collaborative university-industry R&D funded contracts. While the literature provides some advice on how to embark on designing such PPM approach, university-industry collaboration contexts require specific guidance. The research described in this paper aims to make some contribution to theory as well as to practice by discussing the PPM approach adoption in a case study collaborative university-industry R&D funded contract between the University of Minho and Bosch Car Multimedia Portugal S. A., named - HMIExcel. The results show that emphasis should be given to structured objective setting, good progress monitoring and effective communication. The research study is ongoing through the use of a questionnaire and focus groups, in order to improve the presented PPM approach conceptualization.This research is sponsored by the Portugal Incentive System for Research and Technological Development. Project in co-promotion nº36265/2013 (Project HMIExcel - 2013-2015).info:eu-repo/semantics/publishedVersio

    Cancer immunoediting by the innate immune system in the absence of adaptive immunity

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    Cancer immunoediting is the process whereby immune cells protect against cancer formation by sculpting the immunogenicity of developing tumors. Although the full process depends on innate and adaptive immunity, it remains unclear whether innate immunity alone is capable of immunoediting. To determine whether the innate immune system can edit tumor cells in the absence of adaptive immunity, we compared the incidence and immunogenicity of 3'methylcholanthrene-induced sarcomas in syngeneic wild-type, RAG2, and RAG2x γc mice. We found that innate immune cells could manifest cancer immunoediting activity in the absence of adaptive immunity. This activity required natural killer (NK) cells and interferon γ (IFN-γ), which mediated the induction of M1 macrophages. M1 macrophages could be elicited by administration of CD40 agonists, thereby restoring editing activity in RAG2x γc mice. Our results suggest that in the absence of adaptive immunity, NK cell production of IFN-γ induces M1 macrophages, which act as important effectors during cancer immunoediting

    Enhanced AGAMOUS expression in the centre of the Arabidopsis flower causes ectopic expression over its outer expression boundaries

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    Spatial regulation of C-function genes controlling reproductive organ identity in the centre of the flower can be achieved by adjusting the level of their expression within the genuine central expression domain in Antirrhinum and Petunia. Loss of this control in mutants is revealed by enhanced C-gene expression in the centre and by lateral expansion of the C-domain. In order to test whether the level of central C-gene expression and hence the principle of ‘regulation by tuning’ also applies to spatial regulation of the C-function gene AGAMOUS (AG) in Arabidopsis, we generated transgenic plants with enhanced central AG expression by using stem cell-specific CLAVATA3 (CLV3) regulatory sequences to drive transcription of the AG cDNA. The youngest terminal flowers on inflorescences of CLV3::AG plants displayed homeotic features in their outer whorls indicating ectopic AG expression. Dependence of the homeotic feature on the age of the plant is attributed to the known overall weakening of repressive mechanisms controlling AG. Monitoring AG with an AG-I::GUS reporter construct suggests ectopic AG expression in CLV3::AG flowers when AG in the inflorescence is still repressed, although in terminating inflorescence meristems, AG expression expands to all tissues. Supported by genetic tests, we conclude that upon enhanced central AG expression, the C-domain laterally expands necessitating tuning of the expression level of C-function genes in the wild type. The tuning mechanism in C-gene regulation in Arabidopsis is discussed as a late security switch that ensures wild-type C-domain control when other repressive mechanism starts to fade and fail

    Lateral presentation alters overall viewing strategy

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    Eye tracking has been used during face categorisation and identification tasks to identify perceptually salient facial features and infer underlying cognitive processes. However, viewing patterns are influenced by a variety of gaze biases, drawing fixations to the centre of a screen and horizontally to the left side of face images (left-gaze bias). In order to investigate potential interactions between gaze biases uniquely associated with facial expression processing, and those associated with screen location, face stimuli were presented in three possible screen positions to the left, right and centre. Comparisons of fixations between screen locations highlight a significant impact of the screen centre bias, pulling fixations towards the centre of the screen and modifying gaze biases generally observed during facial categorisation tasks. A left horizontal bias for fixations was found to be independent of screen position but interacting with screen centre bias, drawing fixations to the left hemi-face rather than just to the left of the screen. Implications for eye tracking studies utilising centrally presented faces are discussed
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