1,526 research outputs found
Scharp on inconsistent concepts and their engineered replacements, or: Can we mend these broken things?
Kevin Scharp’s influential work on the alethic paradoxes combines an extensively developed inconsistency theory with a substantial conceptual engineering project. I argue that Scharp’s inconsistency theory is in tension with his conceptual engineering project: the inconsistency theory includes an account of concepts that implies that the conceptual engineering project will fail. I recommend that Scharp revises his account of concepts, and show how doing so allows him to resolve the tension. The discussion is important for ongoing work on conceptual engineering. Firstly, it is important to get clear on whether Scharp’s conceptual engineering project is—or could be—successful. Secondly, the issues discussed herein may generalise to other conceptual engineering projects, such as explication and ameliorative projects. In particular, the discussion has implications for how conceptual engineers can think about concepts and their relation to how we use words
Impact of lightning-NO on eastern United States photochemistry during the summer of 2006 as determined using the CMAQ model
A lightning-nitrogen oxide (NO) algorithm is implemented in the Community Multiscale Air Quality Model (CMAQ) and used to evaluate the impact of lightning-NO emissions (LNO<sub>x</sub>) on tropospheric photochemistry over the United States during the summer of 2006. <br><br> For a 500 mole per flash lightning-NO source, the mean summertime tropospheric NO<sub>2</sub> column agrees with satellite-retrieved columns to within −5 to +13%. Temporal fluctuations in the column are moderately well simulated; however, the addition of LNO<sub>x</sub> does not lead to a better simulation of day-to-day variability. The contribution of lightning-NO to the model column ranges from &sim;10% in the northern US to >45% in the south-central and southeastern US. Lightning-NO adds up to 20 ppbv to upper tropospheric model ozone and 1.5–4.5 ppbv to 8-h maximum surface layer ozone, although, on average, the contribution of LNO<sub>x</sub> to model surface ozone is 1–2 ppbv less on poor air quality days. LNO<sub>x</sub> increases wet deposition of oxidized nitrogen by 43% and total deposition of nitrogen by 10%. This additional deposition reduces the mean magnitude of the CMAQ low-bias in nitrate wet deposition with respect to National Atmospheric Deposition monitors to near zero. <br><br> Differences in urban/rural biases between model and satellite-retrieved NO<sub>2</sub> columns were examined to identify possible problems in model chemistry and/or transport. CMAQ columns were too large over urban areas. Biases at other locations were minor after accounting for the impacts of lightning-NO emissions and the averaging kernel on model columns. <br><br> In order to obtain an upper bound on the contribution of uncertainties in NO<sub>y</sub> chemistry to upper tropospheric NO<sub>x</sub> low biases, sensitivity calculations with updated chemistry were run for the time period of the Intercontinental Chemical Transport Experiment (INTEX-A) field campaign (summer 2004). After adjusting for possible interferences in NO<sub>2</sub> measurements and averaging over the entire campaign, these updates reduced 7–9 km biases from 32 to 17% and 9–12 km biases from 57 to 46%. While these changes lead to better agreement, a considerable unexplained NO<sub>2</sub> low-bias remains in the uppermost troposphere
How to find an attractive solution to the liar paradox
The general thesis of this paper is that metasemantic theories can play a central role in determining the correct solution to the liar paradox. I argue for the thesis by providing a specific example. I show how Lewis’s reference-magnetic metasemantic theory may decide between two of the most influential solutions to the liar paradox: Kripke’s minimal fixed point theory of truth and Gupta and Belnap’s revision theory of truth. In particular, I suggest that Lewis’s metasemantic theory favours Kripke’s solution to the paradox over Gupta and Belnap’s. I then sketch how other standard criteria for assessing solutions to the liar paradox, such as whether a solution faces a so-called revenge paradox, fit into this picture. While the discussion of the specific example is itself important, the underlying lesson is that we have an unused strategy for resolving one of the hardest problems in philosophy
c-erbB-4 protein expression in human breast cancer
The Type 1 family of growth factor receptors includes epidermal growth factor receptor (EGFR), c- erb B-2, c- erb B-3 and c- erb B-4. Overexpression of the first two members is associated with poorer prognosis in patients with breast carcinoma. In this study we examined the expression of c- erb B-4 protein using the monoclonal antibody HFR-1. A total of 127 consecutive cases of primary operable invasive breast carcinoma presenting between 1975 and 1977 were studied. All patients were managed by simple mastectomy or conservation surgery with radiotherapy and no adjuvant therapy given. Long-term follow-up was maintained. Routine, formalin-fixed, paraffin-embedded tumour samples were used and sections were stained immunohistochemically using the Duet StreptABC method. Immunoreactivity was classified using a simple semi-quantitative scoring method. Protein expression was generally low but definite positive cytoplasmic, membranous and nuclear reactivity was identified in 58%, 41% and 25% of cases respectively. Expression at all three sites demonstrated significant inverse associations were histological grade. In addition, membrane accentuation correlated inversely with the Nottingham Prognostic Index (NPI), while cytoplasmic reactivity showed a positive association with c- erb B-3 expression. No significant associations were found with disease-free interval or survival. The results of this study demonstrate that higher levels of c- erb B-4 protein expression are associated with a more differentiated histological phenotype in contrast to the other members of the Type 1 family. Larger series with extended follow-up will be required to ascertain definitively the prognostic value of c- erb B-4 expression in breast carcinoma. © 2000 Cancer Research Campaig
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Ammonia Emissions in the United States, European Union, and China Derived by High-Resolution Inversion of Ammonium Wet Deposition Data: Interpretation with a New Agricultural Emissions Inventory (MASAGE_NH3)
We use the adjoint of a global 3-D chemical transport model (GEOS-Chem) to optimize ammonia emissions in the U.S., European Union, and China by inversion of 2005–2008 network data for wet deposition fluxes. Optimized emissions are derived on a 2° × 2.5° grid for individual months and years. Error characterization in the optimization includes model errors in precipitation. Annual optimized emissions are for the contiguous U.S., for the European Union, and for China. Comparisons to previous inventories for the U.S. and European Union show consistency in annual totals but some large spatial and seasonal differences. We develop a new global bottom-up inventory of emissions (Magnitude And Seasonality of Agricultural Emissions model for NH3 (MASAGE_NH3)) to interpret the results of the adjoint optimization. MASAGE_NH3 provides information on the magnitude and seasonality of emissions from individual crop and livestock sources on a 0.5° × 0.5° grid. We find that U.S. emissions peak in the spring in the Midwest due to corn fertilization and in the summer elsewhere due to manure. The seasonality of European emissions is more homogeneous with a well-defined maximum in spring associated with manure and mineral fertilizer application. There is some evidence for the effect of European regulations of emissions, notably a large fall decrease in northern Europe. Emissions in China peak in summer because of the summertime application of fertilizer for double cropping.Engineering and Applied Science
Combining Bayesian methods and aircraft observations to constrain the HO. + NO2 reaction rate
Tropospheric ozone is the third strongest greenhouse gas, and has the highest uncertainty in radiative forcing of the top five greenhouse gases. Throughout the troposphere, ozone is produced by radical oxidation of nitrogen oxides (NOx = NO + NO2). In the upper troposphere (8–10 km), current chemical transport models under-estimate nitrogen dioxide (NO2) observations. Improvements to simulated NOx production from lightning have increased NO2 predictions, but the predictions in the upper troposphere remain biased low. The upper troposphere has low temperatures (T < 250 K) that increase the uncertainty of many important chemical reaction rates. This study constrains uncertain reaction rates by combining model predictions with measurements from the Intercontinental Chemical Transport Experiment-North America observational campaign. The results show that the nitric acid formation rate, which is the dominant sink of NO2 and radicals, is currently over-estimated by 22% in the upper troposphere. The results from this study suggest that the temperature sensitivity of nitric acid formation is lower than currently recommended. Since the formation of nitric acid removes nitrogen dioxide and radicals that drive the production of ozone, the revised reaction rate will affect ozone concentrations in upper troposphere impacting climate and air quality in the lower troposphere
The Explication Defence of Arguments from Reference
In a number of influential papers, Machery, Mallon, Nichols and Stich have presented a powerful critique of so-called arguments from reference, arguments that assume that a particular theory of reference is correct in order to establish a substantive conclusion. The critique is that, due to cross-cultural variation in semantic intuitions supposedly undermining the standard methodology for theorising about reference, the assumption that a theory of reference is correct is unjustified. I argue that the many extant responses to Machery et al.’s critique do little for the proponent of an argument from reference, as they do not show how to justify the problematic assumption. I then argue that it can in principle be justified by an appeal to Carnapian explication. I show how to apply the explication defence to arguments from reference given by Andreasen (for the biological reality of race) and by Churchland (against the existence of beliefs and desires)
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