Synthetic Axion Response with Spacetime Crystals

Here, we show that spacetime modulations provide an exciting route to realize complex nonreciprocal couplings, and in particular the elusive axion response. We develop an analytical formalism to homogenize anisotropic spacetime crystals in the long wavelength limit. It is found that spacetime crystals with suitable glide-rotation symmetry can have a giant axion-type response, several orders of magnitude larger than in natural materials. The nonreciprocal axion response may have interesting applications in optics, for example in electromagnetic isolation, and in addition may enable exciting new forms of light-wave interactions

Ill-defined Topological Phases in Dispersive Photonic Crystals

In recent years there has been a great interest in topological materials and in their fascinating properties. Topological band theory was initially developed for condensed matter systems, but it can be readily applied to arbitrary wave platforms with little modifications. Thus, the topological classification of optical systems is usually regarded as being mathematically equivalent to that of condensed matter systems. Surprisingly, here we find that both the particle-hole symmetry and the dispersive nature of nonreciprocal photonic materials may lead to situations where the usual topological methods break-down and the Chern topology becomes ill-defined. It is shown that due to the divergence of the density of photonic states in plasmonic systems the gap Chern numbers can be non-integer notwithstanding that the relevant parametric space is compact. In order that the topology of a dispersive photonic crystal is well defined, it is essential to take into account the nonlocal effects in the bulk-materials. We propose two different regularization methods to fix the encountered problems. Our results highlight that the regularized topologies may depend critically on the response of the bulk materials for large k

Asymmetric Cherenkov Emission in a Topological Plasmonic Waveguide

Here, we investigate the Cherenkov emission by an array of moving electric charges in the vicinity of a topologically nontrivial gyrotropic material. It is shown that the nonreciprocal material response may result in a robustly asymmetric Cherenkov emission, such that the spectrum of the emitted radiation and the stopping power depend strongly on the sign of the particle velocity. It is demonstrated that the main emission channels are determined by the unidirectional edge states supported by the topological material. We consider as examples both magnetized plasmas and Weyl semi-metals. The latter may exhibit a spontaneous nonreciprocal response without a biasing magnetic field

Local scale dynamics to promote the sustainable management of construction and demolition waste

2_(Des)construir_Economia_Circular). This work was also supported by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) under the project LA/P/0069/2020 granted to the Associate Laboratory ARNET, and the strategic project UIDB/04292/2020 granted to MARE - Marine and Environmental Sciences Centre.On a local scale, municipalities often incur high costs as a result of the illegal dumping of construction and demolition waste (CDW), due to gaps in awareness and training, a lack of adequate oversight actions or infrastructure and equipment. Moreover, there is a loss of resources, failing to close the loop of the circular economy. Six participatory workshops were implemented in 2021, via videoconference due to the Covid-19 pandemic, in a rural Portuguese region, to understand the contribution of local scale dynamics in the promotion of CDW management from an operational perspective. Three of them were dedicated to municipal technicians (39 participants, on average) and the other three to representatives of micro and small construction companies (25 participants, on average). The results reveal that strategies must rely on investment in local solutions to optimise logistics and cost issues, cooperation between stakeholders, and improving the market for recycled aggregates. Also, support for information, awareness, and training is essential, focusing on good practices onsite and oversight procedures. Additionally, municipalities were involved in the prioritisation of legal framework issues, and micro and small construction companies concerning the determinants contributing for their behaviour change. These findings contribute to solving gaps in the literature, useful for researchers and decision-makers in rural or less developed areas.publishersversionpublishe

Study of Xenopus orthologs of novel genes expressed in the mouse AVE

info:eu-repo/semantics/publishedVersio

Industrial development in east Timor: an exploratory study of attitudes and perceptions towards the future

Industrialization is essential for the economic development of a country (Porter, 2004). There are few examples of countries that have made the transition without industrialization, much at the expense of the existence of valuable natural resources (such as oil and diamonds), but with the resulting social inequalities. Industrialization is the normal process for the development of the economies, associated with the phenomenon of globalization of the industry and markets, allows the rapid growth of the same. Take the case of China, which in just over twenty years, went from a really rural to an industrial power in global terms (UNIDO, 2009). Why promote industrialization in poor countries? Because if the developed countries to support industrialization in developing countries benefit from cheaper manufactured goods and the process allows to reduce the gap and inequalities between developed and developing countries (UNIDO, 2009). East Timor was an overseas province of Portugal until 1974 and for 450 years. After this period, the territory was invaded and occupied by Indonesia, a situation that lasted until the referendum held on August 30, 1999. The process leading up to this historic event was long and difficult but with the support of the United Nations, selfdetermination has finally arrived in East Timor in 2002. The proposal of the government of East Timor to the economic development is a strategic long term model and intends to reflect the will and aspirations of the people. Being a young country, post-conflict and with low incomes, it is pointed out the need to implement a unique and specific strategy to the country in order to bring prosperity. One way to achieve these aspirations may pass through private sector investment through the creation and implementation of industry in the country. This allows for increased employment, improved living conditions of the Timorese people and consequently the economic development of Timor-Leste, reinforcing the message widely disseminated in "Goodbye Conflict, Welcome Development". For the period 2011-2030, the first decade will focus on creating the basic conditions for development in all areas: infrastructure, education and training, health, agricultural productivity and food selfsufficiency, sustainable urbanization and development of important sectors industry and services. Private investment in Small and Medium Enterprises (SMEs) and Research and Experimental Development (R&D) in key sectors are one of the four pillars of the economic framework by 2020, presented by the government of East Timor (PED 2010). The present study aims to understand the attitudes and perceptions of the East Timorese in relation to industrial development of the country. Taking as a starting point, a survey of the population of East Timor, named as Projeto Timor, we present and discuss the results obtained on various issues such as attitudes in relation to existing industrial development potential of the country, perceived advantages and disadvantages of industrialization and industrial sectors that are perceived as more relevant to East Timor

Project Timor: a study to the industrial development of East Timor

East Timor is a young country, post-conflict and with low incomes, it is pointed out the need to implement a strategy in order to bring prosperity. One way to achieve these aspirations may pass through private sector investment through the creation and implementation of industry in the country. The present project intends to define a set of guidelines for the implementation of an industrial unit in East Timor. With the goal of identifying industrial areas most relevant to East Timor and taking as a starting point the case study of Timorese reality, a survey was held with Timorese population and information was collected with governmental entities as well with some industry. Results suggest that respondents recognize the importance of creating a manufacturing industry. Nevertheless the perceived advantages of employment and development, the respondents have concerns with environment and land conflicts with community. The coconut oil industry is considered the most important food industry, followed by the salt industry and the industries for the use of cork (baked). Cement industry is the most important construction materials’ industry. The results presented are an important insight in terms of the expectations and attitudes of East Timor population concerning the establishment of manufacturing industry