1,569 research outputs found

    Traditional Ecological Knowledge in Canada

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    Traditional Ecological Knowledge (TEK) is becoming more prominent in land management programs in Canada. While it was largely dismissed for quite some time since colonization began in Canada, it is increasingly valued for its integral understanding and accurate knowledge of local ecosystems. Canadian land management regimes were selected as case studies in order to broaden understanding of how TEK is used in modern land management scenarios. Discussion elaborates on other uses of TEK aside from land management and how further research and documentation of TEK could benefit ecosystems and humans in the face of a changing climate, declining biodiversity, threatened and endangered species, and increasing intensity and incidences of wildfire

    Effects of Alkali Water on Dairy Products

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    Alkali water, or water containing an unusual amount of soluble minerals, especially sulphates, is chiefly found in arid and semi-arid regions. Since the minerals are in the soil, the amount and kind of minerals contained in the water varies according to kind of soil lay of land, kind of cultivation, manured or unmanured, drained or undrained, and climatic conditions. The amount and kind of minerals found in the examined and analyzed water from the different wells may be found in Tables I and II. Many inquiries were received from localities in which alkali water is most prevalent relative to the effects of its use in connection with the varied phases of the dairy industry. Experience of certain dairy farmers indicated that the milk from cows drinking alkali water did not coagulate normally for cheese-making purposes when rennet was added. Others refuse to let the cows drink it, fearing that the cows and the milk might be injured, while other dairy farmers thought that washing the butter in alkali water would affect the butter. At the National Creamery Butter Makers Convention held in St. Louis in 1907, a creamery operator from an adjoining state asked the question, Is it injurious to wash butter in alkali butter? In this large audience composed of practical and scientific dairy and creamery men, no one was able to give a definite answer

    Renormalization-group running of the cosmological constant and its implication for the Higgs boson mass in the Standard Model

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    The renormalization-group equation for the zero-point energies associated with vacuum fluctuations of massive fields from the Standard Model is examined. Our main observation is that at any scale the running is necessarily dominated by the heaviest degrees of freedom, in clear contradistinction with the Appelquist & Carazzone decoupling theorem. Such an enhanced running would represent a disaster for cosmology, unless a fine-tuned relation among the masses of heavy particles is imposed. In this way, we obtain mH550GeVm_H \simeq 550 GeV for the Higgs mass, a value safely within the unitarity bound, but far above the more stringent triviality bound for the case when the validity of the Standard Model is pushed up to the grand unification (or Planck) scale.Comment: 11 pages, LaTex2

    Microstructural Transformations And Kinetics Of High-Temperature Heterogeneous Gasless Reactions By High-Speed X-Ray Phase-Contrast Imaging

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    Heterogeneous gasless reactive systems, including high-energy density metal-nonmetal compositions, have seen increasing study due to their various applications. However, owing to their high reaction temperature, short reaction time, and small scale of heterogeneity, investigation of their reaction mechanisms and kinetics is very difficult. In this study, microstructural changes and the kinetics of product layer growth in the W-Si system was investigated using a high-speed x-ray phase-contrast imaging technique. Using the Advanced Photon Source of Argonne National Laboratory, this method allowed direct imaging of irreversible reactions in the W-Si reactive system at frame rates up to 36 000 frames per second with 4-microsecond exposure and spatial resolution of 1micrometerser. Details of the Si melt and reactions between W and Si, that are unable to be viewed with visible-light imaging, were revealed. These include processes such as the initiation of nucleated melting and other physical phenomena that provide insight into the mixing of reactants and subsequent reaction. Through the use of this imaging technique and future optimization in the imaging process, a model for accurately identifying kinetics of chemical reactions, both spatially and temporally, is also proposed

    Translating transactions: markets as epistemic and moral spheres

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    In this Modern Asian Studies book symposium, scholars of South Asia analyse the political, ethical, and epistemic aspects of market life. They build on the 2020 Cambridge volume, Rethinking Markets in Modern India: Embedded Exchange and Contested Jurisdiction, edited by Ajay Gandhi, Barbara Harriss-White, Douglas Haynes, and Sebastian Schwecke. This interdisciplinary conversation approaches transactional realms from the disciplines of history, anthropology, development studies, and political economy. The symposium’s contributors examine a range of pertinent issues that encompass customary forms of exchange and capitalist aspects of trade. Among the topics discussed are those of market fetishism, bazaar knowledge, social embeddedness, forms of transactional representation and translation, and institutional and regulatory contexts for commerce.Global Challenges (FGGA

    The low-lying excitations of polydiacetylene

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    The Pariser-Parr-Pople Hamiltonian is used to calculate and identify the nature of the low-lying vertical transition energies of polydiacetylene. The model is solved using the density matrix renormalisation group method for a fixed acetylenic geometry for chains of up to 102 atoms. The non-linear optical properties of polydiacetylene are considered, which are determined by the third-order susceptibility. The experimental 1Bu data of Giesa and Schultz are used as the geometric model for the calculation. For short chains, the calculated E(1Bu) agrees with the experimental value, within solvation effects (ca. 0.3 eV). The charge gap is used to characterise bound and unbound states. The nBu is above the charge gap and hence a continuum state; the 1Bu, 2Ag and mAg are not and hence are bound excitons. For large chain lengths, the nBu tends towards the charge gap as expected, strongly suggesting that the nBu is the conduction band edge. The conduction band edge for PDA is agreed in the literature to be ca. 3.0 eV. Accounting for the strong polarisation effects of the medium and polaron formation gives our calculated E(nBu) ca. 3.6 eV, with an exciton binding energy of ca. 1.0 eV. The 2Ag state is found to be above the 1Bu, which does not agree with relaxed transition experimental data. However, this could be resolved by including explicit lattice relaxation in the Pariser- Parr-Pople-Peierls model. Particle-hole separation data further suggest that the 1Bu, 2Ag and mAg are bound excitons, and that the nBu is an unbound exciton.Comment: LaTeX, 23 pages, 4 postscript tables and 8 postscript figure

    What makes me screen for HIV? Perceived barriers and facilitators to conducting recommended routine HIV testing among primary care physicians in the southeastern United States

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    The Centers for Disease Control and Prevention have recommended routinely testing patients (aged 13-64) for HIV since 2006. However, many physicians do not routinely test. From January 2011 to March 2012, we conducted 18 in-depth individual interviews and explored primary care physicians' perceptions of barriers and facilitators to implementing routine HIV testing in North Carolina. Physicians' comments were categorized thematically and fell into 5 groups: policy, community, practice, physician, and patient. Lack of universal reimbursement was identified as the major policy barrier. Participants believed endorsement from the United States Preventive Services Tasks Force would facilitate adoption of routine HIV testing policies. Physicians reported HIV/AIDS stigma, socially conservative communities, lack of confidentiality, and rural geography as community barriers. Physicians believed public HIV testing campaigns would legitimize testing and decrease stigma in communities. Physicians cited time constraints and competing clinical priorities as physician barriers that could be overcome by delegating testing to nursing staff. HIV test refusal, low HIV risk perception, and stigma emerged as patient barriers. Physicians recommended adoption of routine HIV testing for all patients to facilitate and destigmatize testing. Physicians continue to experience a variety of barriers when implementing routine HIV testing in primary care settings. Our findings support multilevel approaches to enhance physician routine HIV testing in primary care settings. © The Author(s) 2014

    Topological doping and the stability of stripe phases

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    We analyze the properties of a general Ginzburg-Landau free energy with competing order parameters, long-range interactions, and global constraints (e.g., a fixed value of a total ``charge'') to address the physics of stripe phases in underdoped high-Tc and related materials. For a local free energy limited to quadratic terms of the gradient expansion, only uniform or phase-separated configurations are thermodynamically stable. ``Stripe'' or other non-uniform phases can be stabilized by long-range forces, but can only have non-topological (in-phase) domain walls where the components of the antiferromagnetic order parameter never change sign, and the periods of charge and spin density waves coincide. The antiphase domain walls observed experimentally require physics on an intermediate lengthscale, and they are absent from a model that involves only long-distance physics. Dense stripe phases can be stable even in the absence of long-range forces, but domain walls always attract at large distances, i.e., there is a ubiquitous tendency to phase separation at small doping. The implications for the phase diagram of underdoped cuprates are discussed.Comment: 18 two-column pages, 2 figures, revtex+eps
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