Comment on: Nonmonotonic dx2−y2d_{x^{2}-y^{2}} Superconducting Order Parameter in Nd2−x_{2-x}Cex_xCuO4_4

In a recent letter Blumberg and collaborators claim that a non-monotonic $d_{x^2-y^2}$ form for the superconducting order parameter is required to explain their Raman scattering measurements in Nd$_{2-x}$Ce$_x$CuO$_4$ . In this comment we show with a simple model calculation that the basis for this conclusion is insufficient. The proposed functional dependence of the gap is neither consistent with their measured spectra nor compatible with other experimental results. Therefore the issue of the superconduing gap in electron-doped systems cannot be considered solved by now.Comment: Comment to the paper by Blumberg et al., Phys. Rev. Lett., 88, 107002 (2002

Quantum Interference Phenomena Between Impurity States in d-wave Superconductors

We investigate the mutual influence of impurities in two-dimensional d-wave superconductors involving self-consistent solutions of the Bogoliubov-de Gennes equations. The local order parameter suppression, the local density of states (LDOS) as well as the interference of impurity-induced structures are analyzed. We employ an impurity position averaging scheme for the DOS that does not neglect these interference effects, as the commonly used $T$-matrix approaches do.Comment: 4 eps figures, presented at SNS200

Pollutant emissions in common-rail diesel engines in extraurban cycle: rapeseed oils vs diesel fuel

The new energy strategy of EU (i.e., Directive 2009/28/EC) requires increasing the use of biofuels in transports up to at least 10% of the total fuel consumption. In the last years, the share of Diesel engines in automotive applications reached about 55% in EU market, thus trying to widen the alternatives to Diesel fuel is very important. In this framework straight vegetable oils (SVO) can represent one of the available possibilities at least in some specific applications (i.e., public transportation, hybrid or marine propulsion, etc.). SVO properties may be very different form Diesel fuel, thus operating a Diesel engine with SVO might result in some problems, especially in automotive configuration where the electronic unit acts as if it is working with Diesel fuel. This reflects in possible engine power and torque reduction, maintenance problems, and pollutant emissions during vehicles running. The latter aspect is the focus of the present paper. In this work, we used a turbocharged, four stroke, four cylinders, water cooled, commonrail multijet Diesel engine in automotive configuration to simulate the extraurban cycle according to the EU standard, comparing pollutant emissions in case of SVO and gasoil fuelling

TOWARDS A ZERO WASTE URBANISM: A MANIFESTO FOR SUSTAINABLE FUTURES

Pressing global environmental problems can be solved only by facing the social problems within society and vice versa. These crises can be approached from different perspectives. In 2016, an estimated 2.01 billion tonnes of municipal solid waste were generated and this number is increasing fast. The problem of where and how to dispose of this material is an environmental issue that is in need of a solution. This issue is prevalent in cities, which are the main site of production and consumption, as well as rapid urbanisation. Often urbanism refers to something that deals with buildings, roads, and other design elements. However, urbanism is much more, and, as theorised long ago, explores the intersection of the physical structures, the social organization, and the attitudes and ideas that are found in cities. This article considers the zero waste tradition, looking in particular to zero waste cities, and putting it in dialogue with critical traditions, in particular urban political ecology. Zero Waste Urbanism is introduced as a both a fresh perspective and a call for action, not only to design better cities but to change society and rework political systems. By making its key questions those that interrogate power, zero waste urbanism radicalizes the zero waste approach, developing new ways of exploring reality while proposing a reconstructive vision to create sustainable urban futures. In doing so, this work aims to reach both zero waste practitioners, interdisciplinary researchers, and academic activists

Modelling the joint impact of R&D and ICT on productivity: a frontier analysis approach

This study explores the channels through which technological investments affect productivity performance of industrialized economies. Using a Stochastic Frontier Model (SFM) we estimate the productivity effects of R&D and ICT for a large sample of OECD industries between 1973 and 2007, identifying four channels of transmission: input accumulation, technological change, technical efficiency and spillovers. Our results show that ICT has been particularly effective in reducing production inefficiency and in generating inter-industry spillovers, while R&D has raised the rate of technical change and favoured knowledge spillovers within sectors. We also quantify the contribution of technological investments to output and TFP growth documenting that R&D and ICT accounted for almost 95% of TFP growth in the OECD area

Modelling the joint impact of R&D and ICT on productivity: a frontier analysis approach

This study explores the channels through which technological investments affect productivity performance of industrialized economies. Using a Stochastic Frontier Model (SFM) we estimate the productivity effects of R&D and ICT for a large sample of OECD industries between 1973 and 2007, identifying four channels of transmission: input accumulation, technological change, technical efficiency and spillovers. Our results show that ICT has been particularly effective in reducing production inefficiency and in generating inter-industry spillovers, while R&D has raised the rate of technical change and favoured knowledge spillovers within sectors. We also quantify the contribution of technological investments to output and total factor productivity growth documenting that R&D and ICT accounted for almost 95% of productivity growth in the OECD area

Off-shoring, specialization and R&D

This paper investigates whether off-shoring promotes technological specialization by reallocating resources towards high-tech industries and/or stimulating within industry R&D. Using data for the US, Japan and Europe, our results show that material off-shoring promotes high-tech specialization through input reallocation between sectors, while service off-shoring favours technologically advanced production by increasing within-industry productivity, mainly via its positive impact on R&D. Conversely, we find that the increasing fragmentation of core production tasks, captured by narrow off-shoring, has adverse effects on technological specialisation, which suggests that this type of off-shoring is mainly pursued for cost-reduction motives

Capital heterogeneity and the decline of the labour share

We investigate the decline of the labour share in a world characterized by increasing heterogeneity of capital assets. Our results show that, over the 1970-2007 period, the decline of the labour share has been mainly driven by Information and Communication Technology (ICT) assets and is mitigated by increasing investments in R&Dbased knowledge assets. Extending to other forms of intangible capital from 1995 onwards, we find that intangible investments related to innovation increase the labour share while those related to the organisation of firms contribute to its decline, particularly for the low and intermediate skilled workers. Our results are robust to an array of econometric issues, namely heterogeneity, cross-sectional dependence, and endogeneit

Globalisation and the decline of the labour share: a microeconomic perspective

This paper contributes to the infant literature on the determinants of the labour share at the level of individual firms and provides novel insights on the effect of firms’ patterns of internationalisation. The analysis is performed using a rich dataset, covering six EU countries (Austria, France, Germany, Hungary, Italy and Spain), and combining information from the EFIGE survey and Amadeus balance sheets. Our results show that the labour share is lower for exporting firms and for those engaged in foreign direct investments or offshoring activities. These findings are robust to an array of sensitivity tests. Our instrumental variable analysis indicates that causation goes from internationalization to changes in the labour share. Investigation into the channels of the negative impact of internationalisation shows that these effects are not related to the composition of the labour force, nor to technological factors or firm market power. The analysis for subsectors of different technological regimes is consistent with this interpretation