Norco College

Abstract What justifies multimethod research? This chapter draws on recent debates in the philosophy of science on evidential pluralism and places them in dialogue with the evolution of multimethod research in the social sciences. We pay particular attention to the Russo–Williamson hypothesis, which draws on research in the medical and biological sciences to argue that causation typically involves evidence of both association and mechanisms. The chapter demonstrates how this approach has resonance in the social sciences, but also argues that this is but one form that evidential partnerships might take. It shows this by reviewing a new multimethod approach called Large-N Qualitative Analysis, which draws on regularity approaches to causation to make the point and concludes by suggesting a variety of other evidential partnerships that are visible or might be possible.

Abstract. We report results from intercomparison exercises between laboratories that conduct measurements of stable carbon and hydrogen isotope ratios of atmospheric CH4 (δ13C-CH4 and δD-CH4). The offsets between the laboratories are larger than the measurement reproducibility of individual laboratories. To disentangle plausible offsets between worldwide laboratories, we evaluated and critically assessed a large number of intercomparison results documented previously in the literature. The results indicate significant offsets of δ13C-CH4 and δD-CH4 measurements among datasets reported from different laboratories; the data spread over ranges of 0.5 ‰ for δ13C-CH4 and 13 ‰ for δD-CH4. The intercomparison results summarized in this study may be of help when combining isotope datasets from different laboratories in future studies.

High-resolution in situ CO_2 measurements were conducted aboard the NASA DC-8 aircraft during the ARCTAS/POLARCAT field campaign, a component of the wider 2007–2008 International Polar Year activities. Data were recorded during large-scale surveys spanning the North American sub‐Arctic to the North Pole from 0.04 to 12 km altitude
\nin spring and summer of 2008. Influences on the observed CO_2 concentrations were investigated using coincident CO, black carbon, CH_3CN, HCN, O_3, C_2Cl_4, and Δ^(14)CO_2 data, and the FLEXPART model. In spring, the CO_2 spatial distribution from 55°N to 90°N was largely determined by the long-range transport of air masses laden with Asian
\nanthropogenic pollution intermingled with Eurasian fire emissions evidenced by the greater variability in the mid-to-upper troposphere. At the receptor site, the enhancement ratios of CO_2 to CO in pollution plumes ranged from 27 to 80 ppmv ppmv^(−1) with the highest anthropogenic content registered in plumes sampled poleward of 80°N. In summer, the CO_2 signal largely reflected emissions from lightning-ignited wildfires within the boreal forests of
\nnorthern Saskatchewan juxtaposed with uptake by the terrestrial biosphere. Measurements within fresh fire plumes yielded CO_2 to CO emission ratios of 4 to 16 ppmv ppmv^(−1) and a mean CO_2 emission factor of 1698 ± 280 g kg^(−1) dry matter. From the ^(14)C in CO_2 content of 48 whole air samples, mean spring (46.6 ± 4.4‰) and summer (51.5 ± 5‰) Δ^(14)CO_2 values indicate a 5‰ seasonal difference. Although the northern midlatitudes were identified as the emissions source regions for the majority of the spring samples, depleted Δ^(14)CO_2 values were observed in <1% of the data set. Rather, ARCTAS Δ^(14)CO_2 observations (54%) revealed predominately a pattern of positive disequilibrium (1–7‰) with respect to background regardless of season owing to both heterotrophic respiration and fire-induced combustion of biomass. Anomalously enriched Δ^(14)CO_2 values (101–262‰) measured
\nin emissions from Lake Athabasca and Eurasian fires speak to biomass burning as an increasingly important contributor to the mass excess in Δ^(14)CO_2 observations in a warming
\nArctic, representing an additional source of uncertainty in the quantification of fossil fuel CO_2.

In contemplating the future of aging, it is helpful to recognize that aging postponement, arrest, prevention, and reversal are commonplace but still under-appreciated natural and experimental phenomena. Aging is apparently completely preventable for prolonged periods in many whole animals by nutritional cues that are not confined to calorie restriction. Aging can be substantially postponed by interfering with active life-shortening processes that are triggered by sexual maturation and reproduction in most species, perhaps including humans, but, contrary to the idea that active life shortening is necessitated by a tradeoff against reproduction, aging can also be dramatically postponed by sexual maturation and reproduction (“negative reproductive costs”) in many species, including mammals. Many fundamental age-related changes are actually reversible in adults or adult systems by the application of simple physiological interventions (“segmental aging reversal”). These reversible elemental aspects of aging include, for example, reduced transcription, reduced translation, altered gene expression, reduced DNA repair, reduced mitochondrial function, reduced regenerative capacity, replicative senescence, lipofuscin accumulation, reduced immune function, thymic involution, loss of reproductive cycling in females, age-related organ atrophy, and hair graying and balding. In addition, many aging phenotypes appear to be interlinked, such that correction of one or a few central aging pathways leads to the correction of multiple downstream pathways without the need for specific intervention in any of these dependent pathways. Collectively, such observations reveal aging on multiple levels and in diverse phyla to be driven by biological mechanisms that are considerably more accessible than is classically expected. This body of observations implies that the future of human aging can be substantially different than its past and supports recent excitement over the possibilities of human intervention.

Abstract Type 347H SS was specified for the tubulars in a Refinery Lube Oil Vacuum Flasher Heater. The heater was designed for tube metal temperatures of 565°C (1050°F), and the tubes were specified to be stabilized annealed in order to resist polythionic acid stress corrosion cracking (PTA-SCC). Testing was performed to determine if resistance to PTA-SCC had been compromised during fabrication of the heater. The test protocol was based on ASTM A-262 Practice C, the 65% nitric acid (Huey) test. All return bends failed the tests, while most of the straight tubes sections passed the tests. The columbium carbide phase was present in very large particles instead of being evenly dispersed as fine particles throughout the matrix. This compromised the effectiveness of the stabilizing anneal and reduced the resistance to PTA-SCC.