Constraints on cosmological birefringence energy dependence from CMB polarization data

We study the possibility of constraining the energy dependence of cosmological birefringence by using CMB polarization data. We consider four possible behaviors, characteristic of different theoretical scenarios: energy-independent birefringence motivated by Chern-Simons interactions of the electromagnetic field, linear energy dependence motivated by a 'Weyl' interaction of the electromagnetic field, quadratic energy dependence, motivated by quantum gravity modifications of low-energy electrodynamics, and inverse quadratic dependence, motivated by Faraday rotation generated by primordial magnetic fields. We constrain the parameters associated to each kind of dependence and use our results to give constraints on the models mentioned. We forecast the sensitivity that Planck data will be able to achieve in this respect.Comment: 15 pages, 5 figures. v2 matches JCAP published versio

Education or just Creativity: what matters most for economic performance?

There is a large consensus among social researchers on the positive role played by human capital on economic performances. The standard way to measure the human capital endowment is to consider the educational attainments by the resident population, usually the share of people with a university degree. Recently, Florida (2002) suggested a different measure of human capital - the “creative class†- based on the actual occupations of individuals in specific jobs like science, engineering, arts, culture, entertainment. However, the empirical analyses carried out so far overlooked a serious measurement problem concerning the clear identification of the education and creativity components of human capital. The main purpose of this paper is to try to disentangle this issue by proposing a disaggregation of human capital into three non-overlapping categories of creative graduates, bohemians and non creative graduates. By using a spatial econometric framework to account for spatial dependence, we assess the concurrent effect of the human capital indicators on total factor productivity for 257 regions of EU27. Our main results indicate that the highly educated creative group is the most relevant one in explaining production efficiency, while the other two categories - non creative graduates and bohemians - exhibit negligible effects. Moreover, a relevant influence is exerted by technological capital and by the level of tolerance providing robust evidence that an innovative, open, inclusive and culturally diverse environment is becoming more and more crucial for productivity enhancements.

Internal protein dynamics shifts the distance to the mechanical transition state

Mechanical unfolding of polyproteins by force spectroscopy provides valuable insight into their free energy landscapes. Most experiments of the unfolding process have been fit to two-state and/or one dimensional models, with the details of the protein and its dynamics often subsumed into a zero-force unfolding rate and a distance x(u)(1D) to the transition state. We consider the entire phase space of a model protein under a constant force, and show that x(u)(1D) contains a sizeable contribution from exploring the full multidimensional energy landscape. This effect is greater for proteins with many degrees of freedom that are affected by force; and surprisingly, we predict that externally attached flexible linkers also contribute to the measured unfolding characteristics

Is dualism still a source of convergence in Europe?

This paper aims at assessing whether dualistic mechanisms represent a significant component of the aggregate labour productivity convergence observed across the European regions in the 1980s. The potential of an explanation of convergence based - in part, at least - on the existence of dualism in some of the initially poorer regions has been largely ignored by the literature. We use a dualistic model based on Dixit (1970) and on Mas-Colell and Razin (1973) to obtain hypotheses to be tested in cross-region growth regressions. In particular, we wish to test whether a high initial allocation of labour in agriculture in fact generates -- in each sector as well as at the aggregate level -- the specific impact on productivity growth (and therefore on convergence) implied by the theory of the dual economy. We use the data-base Regio-Eu set up by CRENoS, with aggregate and sectoral data for 109 territorial units from 1980 to 1990. Our cross-section results are consistent with the major predictions of the dualistic model. While part of the influence exerted by dualistic mechanisms is not easily distinguishable from the one exerted by other mechanisms such as technology diffusion, still the former appears to be a significant component of the whole process of convergence. Ignoring such component could lead to misleading interpretations of the relative roles played by each of the forces behind the process, and to inexact assessments of what actions should be taken - if any - by the European regional policy to help the process become more pervasive. Keywords: Dualism, Growth, Convergence, Regions, Europe JEL: O40, O41, O52, R11

The Role of Ethological Observation for Measuring Animal Reactions to Biotelemetry Devices

This paper presents a methodological approach used to assess the wearability of biotelemetry devices in animals. A detailed protocol to gather quantitative and qualitative ethological observations was adapted and tested in an experimental study of 13 cat participants wearing two different GPS devices. The aim was twofold: firstly, to ascertain the potential interference generated by the devices on the animal body and behavior by quantifying and characterizing it; secondly, to individuate device features potentially responsible for the influence registered, and establish design requirements. This research contributes towards the development of a framework for evaluating the design of wearer-centered biotelemetry interventions for animals, consistent with values advocated by Animal- Computer Interaction researchers

Technological enclaves and industrial districts: An analysis of the regional distribution of innovative activity in Europe

This paper explores the spatial distribution of innovative and productive activity across 109 regions of the European Union, thanks to an original databank on regional patents statistics. The main results worth highlighting are as follows. The technological activity in the EU appears to be highly concentrated, although concentration tends to decline over the eighties. This results from the huge differences between southern and northern Europe. As expected, there is a positive association between the regional distribution of innovative activity and labour productivity. Further, contrary to previous evidence on the United States, our data show a significant link between the specialisation in innovation and in production both at the country and at the industry level. This suggests that localised knowledge spillovers and agglomeration economies foster a local economic system towards a specialisation in both production and technology. More surprisingly there appears a negative correlation between technological concentration and aggregate productivity, that is the European regions which enjoy a more homogeneous distribution of their technological capability across different industrial sectors appear to be also characterised by a higher productivity level. This outcome may suggest the presence of positive inter-industry externalities that favour those regions which succeed in covering a broader range of technological activities.

Towards a Wearer-Centred Framework for Animal Biotelemetry

The emerging discipline of Animal-Computer Interaction (ACI) aims to understand the relation between animals and technology in naturalistic settings, to design technology that can support animals in different contexts and to develop user-centred research methods and frameworks that enable animals to take part in the design process as legitimate contributors [11]. Given existing interspecies differences and communication barriers, measuring the behaviour of animals involved in ACI research can be instrumental to achieving any or all of these aims, as a way of gauging the animals’ patterns, needs and preferences. Indeed, measuring behaviour is a common practice among ACI researchers, who take various approaches to this task [5,15,17,24]. In this respect, the use of biotelemetry devices such as VHF tags and GPS trackers, or bio-logging and environmental sensors has a significant potential [22]. At the same time, biotelemetry has been used for many years in many areas of biological research. Biotelemetry is used to improve the quality of physiological and behavioural data collected from animals and in an attempt to reduce researchers’ intrusion in the animals’ habitat [2]. However, there is evidence that carrying biotelemetry tags may influence the bearer’s physiology and behaviour [20]. Such impacts interfere with the validity of recorded data [14] and the welfare of individual animal wearers [1,3,13]. Neither of these effects are compatible with the animal-centred perspective advocated by ACI, on both scientific and ethical grounds. Our analysis of current body-attached device design and biotelemetry-enabled studies points to a general lack of wearer-centred perspective. To address these issues, we have developed a framework to inform the design of wearer-centred biotelemetry interventions, in order to support the implementation of animal-centred research methodologies and design solutions in ACI and other disciplines