649 research outputs found

    Effect of Zinc on Translocation of Iron in Soybean Plants

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    Structure of Higher Spin Gauge Interactions

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    In a previous paper, higher spin gauge field theory was formulated in an abstract way, essentially only keeping enough machinery to discuss "gauge invariance" of an "action". The approach could be thought of as providing an interface (or syntax) towards an implementation (or semantics) yet to be constructed. The structure then revealed turns out to be that of a strongly homotopy Lie algebra. In the present paper, the framework will be connected to more conventional field theoretic concepts. The Fock complex vertex operator implementation of the interactions in the BRST-BV formulation of the theory will be elaborated. The relation between the vertex order expansion and homological perturbation theory will be clarified. A formal non-obstruction argument is reviewed. The syntactically derived sh-Lie algebra structure is semantically mapped to the Fock complex implementation and it is shown that the recursive equations governing the higher order vertices are reproduced. Global symmetries and subsidiary conditions are discussed and as a result the tracelessness constraints are discarded. Thus all equations needed to compute the vertices to any order are collected. The framework is general enough to encompass all possible interaction terms. Finally, the abstract framework itself will be strengthened by showing that it can be naturally phrased in terms of the theory of categories.Comment: A few changes and additions made in the Introduction. Three references added. Typos corrected. Text agrees with published version in J. Math. Phys. except for minor journal specific proof-reading changes. 61 page

    Mapping material stocks of buildings and mobility infrastructure in the United Kingdom and the Republic of Ireland

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    Understanding the size and spatial distribution of material stocks is crucial for sustainable resource management and climate change mitigation. This study presents high-resolution maps of buildings and mobility infrastructure stocks for the United Kingdom (UK) and the Republic of Ireland (IRL) at 10 m, combining satellite-based Earth observations, OpenStreetMaps, and material intensities research. Stocks in the UK and IRL amount to 19.8 Gigatons or 279 tons/cap, predominantly aggregate, concrete and bricks, as well as various metals and timber. Building stocks per capita are surprisingly similar across medium to high population density, with only the lowest population densities having substantially larger per capita stocks. Infrastructure stocks per capita decrease with higher population density. Interestingly, for a given building stock within an area, infrastructure stocks are substantially larger in IRL than in the UK. These maps can provide useful insights for sustainable urban planning and advancing a circular economy

    A Corpus of Potentially Contradictory Research Claims from Cardiovascular Research Abstracts

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    Background: Research literature in biomedicine and related fields contains a huge number of claims, such as the effectiveness of treatments. These claims are not always consistent and may even contradict each other. Being able to identify contradictory claims is important for those who rely on the biomedical literature. Automated methods to identify and resolve them are required to cope with the amount of information available. However, research in this area has been hampered by a lack of suitable resources. We describe a methodology to develop a corpus which addresses this gap by providing examples of potentially contradictory claims and demonstrate how it can be applied to identify these claims from Medline abstracts related to the topic of cardiovascular disease. Methods A set of systematic reviews concerned with four topics in cardiovascular disease were identified from Medline and analysed to determine whether the abstracts they reviewed contained contradictory research claims. For each review, annotators were asked to analyse these abstracts to identify claims within them that answered the question addressed in the review. The annotators were also asked to indicate how the claim related to that question and the type of the claim. Results: A total of 259 abstracts associated with 24 systematic reviews were used to form the corpus. Agreement between the annotators was high, suggesting that the information they provided is reliable. Conclusions: The paper describes a methodology for constructing a corpus containing contradictory research claims from the biomedical literature. The corpus is made available to enable further research into this area and support the development of automated approaches to contradiction identification

    Yield gains in extra-early maize cultivars of three breeding eras under multiple environments

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    Open Access JournalAvailability of extra-early maize cultivars has facilitated the expansion of maize production into savannas of West and Central Africa (WCA). Fifty-six extra-early maize cultivars of three breeding eras;1995 to 2000, 2001 to 2006, and 2007 to 2012 were evaluated for 2 yr under 24 multiple-stress and 28 non-stress environments in WCA. Objectives of the study were to determine genetic improvement in grain yield of cultivars developed during the breeding eras, and identify high-yielding and s multiple-stress and non-stress environments. Yield gains from era 1 to era 3 under multiple stresses was associated with increased days to anthesis, reduced stalk lodging, and improved husk cover. Cultivars 2004 TZEE-Y Pop STR C4, TZEE-W Pop STR QPM C0, and TZEE-W Pop STR BC2 C0 of era 2; and TZEE-W STR 107 BC1, TZEE-W Pop STR C5, and 2012 TZEE-Y DT STR C5 of era 3 were high-yielding and stable across multiple-stress environments while 98 Syn EE-W from era 1, FERKE TZEE-W STR, TZEE-W Pop STR C3, and TZEE-Y Pop STR QPM C0 from era 2, and TZEE-W Pop STR C5, 2009 TZEE-OR2 STR QPM, 2009 TZEE-W STR, TZEE-Y STR 106, and TZEE-W DT C0 STR C5 from era 3 were outstanding across non-stress environments and should be tested extensively and commercialized. Considerable improvement has been made in breeding for multiple-stress tolerant extra-early maize cultivars

    Microscale distribution patterns of terrestrial bryophytes in a subalpine forest: the use of logistic regression as an interpretive tool

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    This study investigated microhabitat relationships of terrestrial bryophytes in a subalpine forest of coastal British Columbia. Substratum affinities were characterized for dominant bryophytes. Logistic regression analysis was used to gain insight into the ecological determinants of fine scale (0.1 m2) bryophyte distribution by examining the predictive relationship between bryophyte species occurrence and localized environmental conditions, as well as the coverage of other bryophytes. The predictive relationships were compared to evaluate the relative importance of environmental factors versus interspecific interactions in structuring bryophyte communities. The results indicate that bryophytes show unique responses in their relationships to environmental conditions and other bryophytes. Positive feedback appears to be an important process among terrestrial bryophytes in subalpine forests

    Simple sequence repeats in Neurospora crassa: distribution, polymorphism and evolutionary inference

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    <p>Abstract</p> <p>Background</p> <p>Simple sequence repeats (SSRs) have been successfully used for various genetic and evolutionary studies in eukaryotic systems. The eukaryotic model organism <it>Neurospora crassa </it>is an excellent system to study evolution and biological function of SSRs.</p> <p>Results</p> <p>We identified and characterized 2749 SSRs of 963 SSR types in the genome of <it>N. crassa</it>. The distribution of tri-nucleotide (nt) SSRs, the most common SSRs in <it>N. crassa</it>, was significantly biased in exons. We further characterized the distribution of 19 abundant SSR types (AST), which account for 71% of total SSRs in the <it>N. crassa </it>genome, using a Poisson log-linear model. We also characterized the size variation of SSRs among natural accessions using Polymorphic Index Content (PIC) and ANOVA analyses and found that there are genome-wide, chromosome-dependent and local-specific variations. Using polymorphic SSRs, we have built linkage maps from three line-cross populations.</p> <p>Conclusion</p> <p>Taking our computational, statistical and experimental data together, we conclude that 1) the distributions of the SSRs in the sequenced N. crassa genome differ systematically between chromosomes as well as between SSR types, 2) the size variation of tri-nt SSRs in exons might be an important mechanism in generating functional variation of proteins in <it>N. crassa</it>, 3) there are different levels of evolutionary forces in variation of amino acid repeats, and 4) SSRs are stable molecular markers for genetic studies in <it>N. crassa</it>.</p
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