The energy levels of hydrogen-like atomic systems can be calculated with great precision. Starting from their quantum mechanical solution, they have been refined over the years to include the electron spin, the relativistic and quantum field effects, and tiny energy shifts related to the complex structure of the nucleus. These energy shifts caused by the nuclear structure are vastly magnified in hydrogen-like systems formed by a negative muon and a nucleus, so spectroscopy of these muonic ions can be used to investigate the nuclear structure with high precision. Here we present the measurement of two 2S–2P transitions in the muonic helium-4 ion that yields a precise determination of the root-mean-square charge radius of the $\alpha$ particle of 1.67824(83) femtometres. This determination from atomic spectroscopy is in excellent agreement with the value from electron scattering1, but a factor of 4.8 more precise, providing a benchmark for few-nucleon theories, lattice quantum chromodynamics and electron scattering. This agreement also constrains several beyond-standard-model theories proposed to explain the proton-radius puzzle2–5, in line with recent determinations of the proton charge radius6–9, and establishes spectroscopy of light muonic atoms and ions as a precise tool for studies of nuclear properties. The 2S–2P transitions in muonic helium-4 ions are measured using laser spectroscopy and used to obtain an $\alpha$-particle charge-radius value five times more precise than that from electron scattering.

The growing use of wearable devices has been stimulating research efforts in the development of energy harvesters as more portable and practical energy sources alternatives. The field of piezoelectric nanogenerators (PENGs) and triboelectric nanogenerators (TENGs), especially employing zinc oxide (ZnO) nanowires (NWs), has greatly flourished in recent years. Despite its modest piezoelectric coefficient, ZnO is very attractive due to its sustainable raw materials and the facility to obtain distinct morphologies, which increases its multifunctionality. The integration of ZnO nanostructures into polymeric matrices to overcome their fragility has already been proven to be fruitful, nevertheless, their concentration in the composite should be optimized to maximize the harvesters' output, an aspect that has not been properly addressed. This work studies a composite with variable concentrations of ZnO nanorods (NRs), grown by microwave radiation assisted hydrothermal synthesis, and polydimethylsiloxane (PDMS). With a 25 wt % ZnO NRs concentration in a composite that was further micro-structured through laser engraving for output enhancement, a nanogenerator (NG) was fabricated with an output of 6 V at a pushing force of 2.3 N. The energy generated by the NG could be stored and later employed to power small electronic devices, ultimately illustrating its potential as an energy harvesting device.

In this article, characterization of fully patterned zinc-tin oxide (ZTO)-based memristive devices with feature sizes as small as 25 µm2 is presented. The devices are patterned via lift-off with a platinum bottom contact and a gold-titanium top contact. An on/off ratio of more than two orders of magnitude is obtained without the need for electroforming processes. Set operation is a current controlled process, whereas the reset is voltage dependent. The temperature dependency of the electrical characteristics reveals a bulk-dominated conduction mechanism for high resistance states. However, the charge transport at low resistance state is consistent with Schottky emission. Synaptic properties such as potentiation and depression cycles, with progressive increases and decreases in the conductance value under 50 successive pulses, are shown. This validates the potential use of ZTO memristive devices for a sustainable and energy-efficient brain-inspired deep neural network computation.

A remarkably well-preserved, almost complete and articulated new specimen (GP/2E 9266) of Tupandactylus navigans is here described for the Early Cretaceous Crato Formation of Brazil. The new specimen comprises an almost complete skeleton, preserving both the skull and post-cranium, associated with remarkable preservation of soft tissues, which makes it the most complete tapejarid known thus far. CT-Scanning was performed to allow the assessment of bones still covered by sediment. The specimen can be assigned to Tupa. navigans due to its vertical supra-premaxillary bony process and short and rounded parietal crest. It also bears the largest dentary crest among tapejarine pterosaurs and a notarium, which is absent in other representatives of the clade. The new specimen is here regarded as an adult individual. This is the first time that postcranial remains of Tupa. navigans are described, being also an unprecedented record of an articulated tapejarid skeleton from the Araripe Basin.

Abstract Enhancer binding proteins (EBPs) are key players of σ54-regulation that control transcription in response to environmental signals. In the anaerobic microorganism Desulfovibrio vulgaris Hildenborough (DvH), orp operons have been previously shown to be coregulated by σ54-RNA polymerase, the integration host factor IHF and a cognate EBP, OrpR. In this study, ChIP-seq experiments indicated that the OrpR regulon consists of only the two divergent orp operons. In vivo data revealed that (i) OrpR is absolutely required for orp operons transcription, (ii) under anaerobic conditions, OrpR binds on the two dedicated DNA binding sites and leads to high expression levels of the orp operons, (iii) increasing the redox potential of the medium leads to a drastic down-regulation of the orp operons expression. Moreover, combining functional and biophysical studies on the anaerobically purified OrpR leads us to propose that OrpR senses redox potential variations via a redox-sensitive [4Fe?4S]2+ cluster in the sensory PAS domain. Overall, the study herein presents the first characterization of a new Fe?S redox regulator belonging to the σ54-dependent transcriptional regulator family probably advantageously selected by cells adapted to the anaerobic lifestyle to monitor redox stress conditions.

Found in the Upper Jurassic outcrops of Lourinhã, Portugal, and first published in 1997, the Paimogo dinosaur egg clutch is one of Portugal’s most remarkable fossils, with over one hundred eggs preserved in association with embryonic bones, of the allosauroid theropod Lourinhanosaurus. However, many questions about it have remained unanswered, even until the present day. After its discovery, this extraordinary fossil became the keystone of a small local museum, greatly kick-starting regional tourism, while also holding the fossils in trust for future generations to study. More than 20 years later, continually sustained paleontological interest from the public has even given rise to both a highly successful dinosaur theme park in the region and an aspiring UNESCO Geopark. Recently, a multidisciplinary team of preparators, paleontologists, sedimentologists, mineralogists, and geochemists revisited an unopened jacket from the original excavation using an array of techniques to address various questions. Studies are ongoing, but the corpus of information obtained and the methodologies utilized to gather data have offered an opportunity to design an exhibit around the history of the Paimogo clutch, highlighting the scientific methods involved, and asserting the importance of preserving geological heritage for the future, when new tools will doubtlessly become available to provide yet another new look at old fossils. Here, we describe our analytical procedures and present an innovative exhibit designed to introduce to the public the latest advances on the research behind an iconic piece of Portuguese geoheritage, increasing its value both as a research item and as an educational resource.

New technologies, sustainability policies, protectionism and consumers preferences are pushing for the reorganization of the automotive cluster. (ILO, 2020) Due to recent technological advances derived from the application of AI in the domains of autonomous driving, connectivity, automation, and robotics, the automotive sector is evolving from the traditional, linear, product-oriented value chain to a mobility, service oriented one including new players (ILO, 2020). In fact, in the last years, several digital competences centers are supplying the automotive sector and have been installed in Portugal. These changes are put in place to enhance the product quality, to control costs and to improve productivity. The product shift is done to respond to new regulations on environmental protection, and to enable the control of some emergent market niches.
The paper will contribute to answer the question: what are the expectable changes in productivity due to the introduction of AI in the automotive sector and at new players in the automotive value chain in Portugal? Do they have impacts in traditional labour relations in the sector? Did the COVID-19 had an effect in the acceleration of such changes? Does the employment in the automotive sector changed with the recent automation trends in Portugal? Are there signs of improvement in qualifications with increases in automation? Or can we observe a clear job precarity in the automotive labour market with increased application of cyber physical systems in this sector? We want to develop this framework of questions to collect new data and obtain results that will be based on case studies from the automotive cluster. We will use, as well, secondary statistical analysis. Finally, changes in the productivity and labour market will be discussed in relation to the employment volume and skills in the automotive sector.
In this recently approved national project, we will focus on AI (cyber-physical systems, intelligent automation, robotics, IoT) as the most relevant emergent technology to understand the development of automation in this manufacturing sector (Geels et al., 2012; Moniz 2018). R&D investments in industrial processes in general may reflect productivity improvements derived from the increased automation process, but that may not be the general trend. Our empirical data are based until now on initial case studies from the automotive and components sector combined with database search by keywords that sign intelligence automation developments and AI applications selected from national R&D projects on robotics, machine learning, collaborative tools, human-machine interaction and autonomous systems, supported by European structural funds. The implications on industrial productivity and employment will be discussed in relation to automation trends in the automotive sector.

In this paper we will address the impacts on work and employment in Portugal of undergoing reconfigurations in automotive Global Value Chains (GVC). Due to its contributions to employment, exports and production the automotive sector is regarded as strategic for Portugal. Currently, it is caught in the midst of a turmoil, spurred by major trends that are reshaping its global outlook, with perils and opportunities for firms and workers depending on their position in different segments of GVC. The emergence of GVC transformed the patterns of international division of labour, trade and investment. Countries and regions specialize not only in products and services but increasingly in tasks and functions. Value is created globally and is apportioned along the chain depending on the tasks performed, the resources and type of workforce engaged in production in each node, its geographical location and the relative power relations within the production network. Typically, along GVC’s production stages, labour intensive, low skill tasks are ascribed – offshored and subcontracted by lead firms – to firms and workers in peripheral countries, while knowledge intensive, more complex or higher skilled tasks are retained in core regions. The value captured, as well as the share of value ascribed to labour and the quality of employment, are broadly correlated with its position in the chain. GVC, besides firms or even sectors, thus become an appropriate locus for analysing labour processes and employment patterns.
Major trends reconfiguring automotive global networks of production, include: (i) automation; (ii) digitalisation; (iii) electrification of vehicles; (iv) shifting geographies of production; and (v) industrial, employment and social policies. Manufacture of vehicles is known to be an automation-intensive sector permeated by technological developments such as new cyber-physical systems and flexible lightweight robots with an impact on work and employment, particularly on low-skilled workers. National and regional industrial, trade and investment policies articulated with company strategies, are also participating in the reshaping of the automotive GVC and changing the geographies of production. Finally, employment and social policies impinge on and are conditioned by foreign investment and location decisions of automotive multinationals, thus participating in the reshaping of GVC. In order to respond to the main overarching research question (what are the actual and prospective impacts on work and employment in Portugal driven by transitions taking place in the automotive GVC?) an analytical model will be designed. It will place the ongoing and prospective transformations of work and employment patterns as consequence of the interplay of actor’s strategies and public policies, against the background of structures and institutions. The research study will be based on major OEM operating in Portugal (VW, Stellantis, Mitsubishi and Toyota) and on automotive supply chain companies, most of them major player on the automotive GVC (Faurecia, KWD, Vintech, Sodecia, Preh).