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A new regime of carbon counting: the practices and politics of accounting for everyday carbon through C02e
Inspired by the commercial desires of global brands and retailers to access the lucrative green consumer market, carbon is increasingly being counted and made knowable at the mundane sites of everyday production and consumption, from the carbon footprint of a plastic kitchen fork to that of an online bank account. Despite the challenges of counting and making commensurable the global warming impact of a myriad of biophysical and societal activities, this desire to communicate a product or service's carbon footprint has sparked complicated carbon calculative practices and enrolled actors at literally every node of multi-scaled and vastly complex global supply chains. Against this landscape, this paper critically analyzes the counting practices that create the ‘e’ in ‘CO2e’. It is shown that, central to these practices are a series of tools, models and databases which, in building upon previous work (Eden, 2012 and Star and Griesemer, 1989) we conceptualize here as ‘boundary objects’. By enrolling everyday actors from farmers to consumers, these objects abstract and stabilize greenhouse gas emissions from their messy material and social contexts into units of CO2e which can then be translated along a product's supply chain, thereby establishing a new currency of ‘everyday supply chain carbon’. However, in making all greenhouse gas-related practices commensurable and in enrolling and stabilizing the transfer of information between multiple actors these objects oversee a process of simplification reliant upon, and subject to, a multiplicity of approximations, assumptions, errors, discrepancies and/or omissions. Further the outcomes of these tools are subject to the politicized and commercial agendas of the worlds they attempt to link, with each boundary actor inscribing different meanings to a product's carbon footprint in accordance with their specific subjectivities, commercial desires and epistemic framings. It is therefore shown that how a boundary object transforms greenhouse gas emissions into units of CO2e, is the outcome of distinct ideologies regarding ‘what’ a product's carbon footprint is and how it should be made legible. These politicized decisions, in turn, inform specific reduction activities and ultimately advance distinct, specific and increasingly durable transition pathways to a low carbon society
Present state of knowledge of the upper atmosphere 1990: An assessment report
NASA is charged with the responsibility to report on the state of the knowledge of the Earth's upper atmosphere, particularly the stratosphere. Part 1 of this report, issued earlier this year, summarized the objectives, status, and accomplishments of the research tasks supported under NASA's Upper Atmosphere Research Program during the last two years. New findings since the last report to Congress was issued in 1988 are presented. Several scientific assessments of the current understanding of the chemical composition and physical structure of the stratosphere are included, in particular how the abundance and distribution of ozone is predicted to change in the future. These reviews include: a summary of the most recent international assessment of stratospheric ozone; a study of future chlorine and bromine loading of the atmosphere; a review of the photochemical and chemical kinetics data that are used as input parameters for the atmospheric models; a new assessment of the impact of Space Shuttle launches on the stratosphere; a summary of the environmental issues and needed research to evaluate the impact of the newly re-proposed fleet of stratospheric supersonic civil aircraft; and a list of the contributors to this report and the science assessments which have formed our present state of knowledge of the upper atmosphere and ozone depletion
A comparison of current analytical methods for predicting soil-structure interaction due to tunnelling
Current procedures for the assessment of buildings response to tunnelling take into account the effect of soil-structure interaction through the definition of the building stiffness relative to the soil stiffness. Limitations of these procedures are uncertainties in the evaluation of structural parameters and inconsistent results between different methods. In this paper, three existing formulations of the Relative Stiffness Method (RSM) have been critically evaluated by analysing the governing factors in the building stiffness calculation and their effect on the structural damage assessment. The results of a sensitivity study on building height, eccentricity, opening ratio, tunnel depth, soil and masonry stiffness, and trough width parameter quantified the effect of these factors on the considered RSMs. The application of different RSMs to a real masonry building adjacent to the Jubilee Line tunnel excavation underlined the significant effect of window openings, façade stiffness and neutral axis position on the building stiffness calculation and deformation prediction. These results highlight the need for a consistent and robust damage assessment procedure.</p
Three-Dimensional Structure of Conotoxin tx3a: A m-1 Branch Peptide of the M-Superfamily
The M-superfamily, one of eight major conotoxin superfamilies found in the venom of the cone snail, contains a Cys framework with disulfide-linked loops labeled 1, 2, and 3 (- CC1C2C3CC-). M-superfamily conotoxins can be divided into the m-1, -2, -3 and -4 branches, based upon the number of residues located in the third Cys loop between the fourth and fifth Cys residues. Here we provide a three-dimensional solution structure for the m-1 conotoxin tx3a found in the venom of Conus textile. The 15 amino acid peptide, CCSWDVCDHPSCTCC, has disulfide bonds between Cys1 and Cys14, Cys2 and Cys12, and Cys7 and Cys15 typical of the C1- C5, C2-C4, and C3-C6 connectivity pattern seen in m-1 branch peptides. The tertiary structure of tx3a was determined by 2D 1H NMR in combination with the combined assignment and dynamics algorithm for nuclear magnetic resonance (NMR) applications CYANA program. Input for structure calculations consisted of 62 inter- and intraproton, 5 phi angle, and 4 hydrogen bond constraints. The root-mean-square deviation values for the 20 final structures are 0.32 +/- 0.07 Å and 0.84 +/- 0.11 Å for the backbone and heavy atoms, respectively. Surprisingly, the structure of tx3a has a “triple-turn” motif seen in the m-2 branch conotoxin mr3a, which is absent in mr3e, the only other member of the m-1 branch of the M-superfamily whose structure is known. Interestingly, injection of tx3a into mice elicits an excitatory response similar to that of the m-2 branch peptide mr3a, even though the conotoxins have different disulfide connectivity patterns
Quantitation of Aortic Valvular Insufficiency Using Radioactive Tracers: An Experimental Study In Vitro
A method has been developed in vitro for quantitation of aortic valvular insufficiency (Al) based on the use of ladioactive traceis lo genei-ate graphic recordings of the movement of blood out of the ventricle and back again. The regurgitant fraction of stroke volume (peirent of Al) is read from this recording. The method was evaluated in a mechanical heart model by comparing Al values read from the istope recordings and Al values determined volumetrically. The recordings gave excellent agreement with the volumetric results (Corr. Coeff. .9). These in vitro results are of such quality that clinical trials seem justified
A High Fat Diet Increases Bone Marrow Adipose Tissue (MAT) But Does Not Alter Trabecular or Cortical Bone Mass in C57BL/6J Mice
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111767/1/jcp24954.pd
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