Fate of micronutrients and heavy metals in digestate processing using vibrating reversed osmosis as resource recovery technology

This study aims to evaluate the full-scale performance of vibrating membrane filtration (VSEP) technology in resource recovery from the liquid fraction of digestates, while reducing macronutrient concentrations down to dischargeable water. Although increasing attention is paid to mass flow assessment of macronutrients, to date little is known about the fate of micronutrients and heavy metals upon digestate processing. In this research, process streams were characterized and mass balances for micronutrients and heavy metals were performed throughout a complete digestate processing train. The VSEP system operated with reversed osmosis membranes and followed by a lagoon was capable of producing dischargeable water according to Flemish regulatory standards. Concentrates produced by one VSEP filtration of the liquid fraction of digestate and dried thick fractions resulting from solid-liquid separation were rich in macro- and micronutrients, while heavy metal concentrations did not exceed regulatory standards. Hence, these products showed high potential for reuse in agriculture

Hydrogen and vacancy clustering in zirconium

The effect of solute hydrogen on the stability of vacancy clusters in hexagonal closed packed zirconium is investigated with an ab initio approach, including contributions of H vibrations. Atomistic simulations within the density functional theory evidence a strong binding of H to small vacancy clusters. The hydrogen effect on large vacancy loops is modeled through its interaction with the stacking faults. A thermodynamic modeling of H segregation on the various faults, relying on ab initio binding energies, shows that these faults are enriched in H, leading to a decrease of the stacking fault energies. This is consistent with the trapping of H by vacancy loops observed experimentally. The stronger trapping, and thus the stronger stabilization, is obtained for vacancy loops lying in the basal planes, i.e. the loops responsible for the breakaway growth observed under high irradiation dose.Comment: submitte

Export Diversification: What’s behind the Hump?

The paper explores the evolution of export diversification patterns along the economic development path. Using a large database with 156 countries over 19 years at the HS6 level of disaggregation (4’991 product lines) we look for action at the “intensive” and “extensive” margins (diversification of export values among active product lines and by addition of new product lines respectively) using various export concentration indices and the number of active export lines. We also look at new product introduction as an indicator of “export-entrepreneurship”. We find a hump-shaped pattern of export diversification similar to what Imbs and Wacziarg (2003) found for production and employment. Diversification and subsequent re-concentration take place mostly along the extensive margin, although the intensive margin follows the same pattern. This hump-shaped pattern is consistent with the conjecture that countries travel across diversification cones, as discussed in Schott (2003, 2004) and Xiang (2007).international trade, Export diversification

Export Diversification:What’s behind the Hump?

The paper explores the evolution of export diversification patterns along the economic development path. Using a large database with 159 countries over 17 years at the HS6 level of disaggregation (4’998 product lines) we look for action at the “intensive” and “extensive” margins (diversification of export values among active product lines and by addition of new product lines respectively) using various export concentration indices and the number of active export lines. We also look at new product introduction as an indicator of “export-entrepreneurship”. We find a hump-shaped pattern of export diversification similar to what Imbs and Wacziarg (2003) found for production and employment. Low and Middle income countries diversify mostly along the extensive margin whereas high income countries diversify along the intensive margin and ultimately re-concentrate their exports towards fewer products. Such hump-shaped pattern is consistent with the conjecture that countries travel across diversification cones as discussed in Schott (2003, 2004) and Xiang (2007).Export diversification, international trade, Latin America

Trade Diversification, Income, and Growth: What Do We Know?

Export diversification, international trade, Growth and employment

Export Diversification:What's behind the Hump?

The paper explores the evolution of export diversification patterns along the economic development path. Using a large database with 159 countries over 17 years at the HS6 level of disaggregation (4'998 product lines) we look for action at the “intensive” and “extensive” margins (diversification of export values among active product lines and by addition of new product lines respectively) using various export concentration indices and the number of active export lines. We also look at new product introduction as an indicator of “export-entrepreneurship”. We find a hump-shaped pattern of export diversification similar to what Imbs and Wacziarg (2003) found for production and employment. Low and Middle income countries diversify mostly along the extensive margin whereas high income countries diversify along the intensive margin and ultimately re-concentrate their exports towards fewer products. Such hump-shaped pattern is consistent with the conjecture that countries travel across diversification cones as discussed in Schott (2003, 2004) and Xiang (2007).Export diversification;international trade;Latin America

Export Diversification: What's behind the Hump?

The paper explores the evolution of export diversification patterns along the economic development path. Using a large database with 156 countries over 19 years at the HS6 level of disaggregation (4'991 product lines) we look for action at the “intensive” and “extensive” margins (diversification of export values among active product lines and by addition of new product lines respectively) using various export concentration indices and the number of active export lines. We also look at new product introduction as an indicator of “export-entrepreneurship”. We find a hump-shaped pattern of export diversification similar to what Imbs and Wacziarg (2003) found for production and employment. Diversification and subsequent re-concentration take place mostly along the extensive margin, although the intensive margin follows the same pattern. This hump-shaped pattern is consistent with the conjecture that countries travel across diversification cones, as discussed in Schott (2003, 2004) and Xiang (2007).international trade;Export diversification

What are Households Willing to Pay for Better Tap Water Quality ? A Cross-Country Valuation Study

Using a unique cross-section sample from 10 OECD countries, we estimate willingness to pay for better quality of tap water. On the pooled sample, households are only willing to pay 7.5% of the median annual water bill to improve the quality of tap water. The highest relative willingness to pay for better tap water quality was found in the countries with the highest percentage of respondents being unsatisfied with tap water quality because of health concerns. The median willingness to pay in Mexico, Korea and Italy was estimated at 10.1%, 6.4% and 8.8% of the median water bill. The marginal willingness to pay increased with income, education, environmental concern, trust in information from government, and specific concerns with water quality.Contingent valuation, tobit model, water quality, willingness to pay.

Developing a Framework to Assess Financial Stability: Conference Highlights and Lessons

Central banks are still defining their approach to financial stability and are at an early stage in the development of useful models. The Bank of Canada's 2007 economic conference was organized to stimulate progress in the development of financial-stability frameworks. Among the highlights reported here are the discussions centred around three proposed frameworks: a contingent-claims-analysis framework, a semi-structural framework, and structural financial-stability models. Participants also reported on their experiences with stress-testing under the International Monetary Fund's Financial Sector Assessment Program and discussed the implications for financial stability of linkages among payment, clearing, and settlement systems.

Generic Construction of UC-Secure Oblivious Transfer

International audienceWe show how to construct a completely generic UC-secure oblivious transfer scheme from a collision-resistant chameleon hash scheme (CH) and a CCA encryption scheme accepting a smooth projective hash function (SPHF). Our work is based on the work of Abdalla et al. at Asiacrypt 2013, where the authors formalize the notion of SPHF-friendly commitments, i.e. accepting an SPHF on the language of valid commitments (to allow implicit decommitment), and show how to construct from them a UC-secure oblivious transfer in a generic way. But Abdalla et al. only gave a DDH-based construction of SPHF-friendly commitment schemes, furthermore highly relying on pairings. In this work, we show how to generically construct an SPHF-friendly commitment scheme from a collision-resistant CH scheme and an SPHF-friendly CCA encryption scheme. This allows us to propose an instanciation of our schemes based on the DDH, as efficient as that of Abdalla et al., but without requiring any pairing. Interestingly, our generic framework also allows us to propose an instantiation based on the learning with errors (LWE) assumption. For the record, we finally propose a last instanciation based on the decisional composite residuosity (DCR) assumption