45 research outputs found
The quantitative soil pit method for measuring belowground carbon and nitrogen stocks
Many important questions in ecosystem science require estimates of stocks of soil C and nutrients. Quantitative soil pits provide direct measurements of total soil mass and elemental content in depth-based samples representative of large volumes, bypassing potential errors associated with independently measuring soil bulk density, rock volume, and elemental concentrations. The method also allows relatively unbiased sampling of other belowground C and nutrient stocks, including roots, coarse organic fragments, and rocks. We present a comprehensive methodology for sampling these pools with quantitative pits and assess their accuracy, precision, effort, and sampling intensity as compared to other methods. At 14 forested sites in New Hampshire, nonsoil belowground pools (which other methods may omit, double-count, or undercount) accounted for upward of 25% of total belowground C and N stocks: coarse material accounted for 4 and 1% of C and N in the O horizon; roots were 11 and 4% of C and N in the O horizon and 10 and 3% of C and N in the B horizon; and soil adhering to rocks represented 5% of total B-horizon C and N. The top 50 cm of the C horizon contained the equivalent of 17% of B-horizon carbon and N. Sampling procedures should be carefully designed to avoid treating these important pools inconsistently. Quantitative soil pits have fewer sources of systematic error than coring methods; the main disadvantage is that because they are time-consuming and create a larger zone of disturbance, fewer observations can be made than with cores
Sacrifice ratio dispersion within the Euro Zone: what can be learned about implementing a single monetary policy?
This article focuses on the comparison of sacrifice ratios as an indicator for structural dispersion within the euro area over the period 1972â2003. Estimates of the sacrifice ratio, defined as the cumulative output cost arising from permanent inflation reduction, are obtained using structural VAR models. Results from subâperiod analysis as well as 10âyearâperiod rolling estimates lead to two main conclusions. First, empirical evidence displays a recent increase in the average sacrifice ratio, which can be linked to the simultaneous decrease in the average inflation rate: this negative relationship between the initial level of inflation and the cost of disinflation can be seen as a justification for the choice of an inflation objective close to 2% for the European Central Bank (ECB) rather than a target of perfect price stability, potentially very damaging. Second, we cannot provide evidence of any reduction in European sacrifice ratio dispersion, which would suggest that the nominal convergence triggered by the Maastricht Treaty did not involve a true reduction of structural differences. It is likely to be a problem in the stance of a single monetary policy, because structural differences imply asymmetric responses of real national economies to the same monetary impulse.sacrifice ratio, monetary policy, convergence, Economic and Monetary Union (EMU), C22, E32, E52, E58,
Reclassification of Treatment Strategy with Fractional Flow Reserve in Cancer Patients with Coronary Artery Disease
Background and Objectives: Cancer and coronary artery disease (CAD) often coexist. Compared to quantitative coronary angiography (QCA), fractional flow reserve (FFR) has emerged as a more reliable method of identifying significant coronary stenoses. We aimed to assess the specific management, safety and outcomes of FFR-guided percutaneous coronary intervention (PCI) in cancer patients with stable CAD. Materials and Methods: FFR was used to assess cancer patients that underwent coronary angiography for stable CAD between September 2008 and May 2016, and were found to have â„50% stenosis by QCA. Patients with lesions with an FFR > 0.75 received medical therapy alone, while those with FFR †0.75 were revascularized. Procedure-related complications, all-cause mortality, nonfatal myocardial infarction, or urgent revascularizations were analyzed. Results: Fifty-seven patients with stable CAD underwent FFR on 57 lesions. Out of 31 patients with â„70% stenosis as measured by QCA, 14 (45.1%) had an FFR â„ 0.75 and lesions were reclassified as moderate and did not receive PCI nor DAPT. Out of 26 patients with <70% stenosis as measured by QCA, 6 (23%) had an FFR < 0.75 and were reclassified as severe and were treated with PCI and associated DAPT. No periprocedural complications, urgent revascularization, acute coronary syndromes, or cardiovascular deaths were noted. There was a 22.8% mortality at 1 year, all cancer related. Patients who received a stent by FFR assessment showed a significant association with decreased risk of all-cause death (HR: 0.37, 95% CI 0.15â0.90, p = 0.03). Conclusions: Further studies are needed to define the optimal therapeutic approach for cancer patients with CAD. Using an FFR cut-off point of 0.75 to guide PCI translates into fewer interventions and can facilitate cancer care. There was an overall reduction in mortality in patients that received a stent, suggesting increased resilience to cancer therapy and progression. © 2022 by the authors. Licensee MDPI, Basel, Switzerland