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While it is widely agreed that automated and autonomous vehicles may provide safety benefits over vehicles with lower level or no automation, due to other road users there will still likely be situations where a collision is unavoidable. What should a vehicle that is operating autonomously do when it has no choice but to have a collision? And who should decide which vehicle manoeuvre is the most acceptable? These situations create moral dilemmas requiring consideration of the most acceptable and moral action of the vehicle. In this paper we explore current research in this domain and work towards enabling ethical solutions. We identify current experimental work (practical studies rather than theoretical studies) on this problem often contains fundamental flaws due to the lack of real-world validity within the studied scenarios. We argue that morality is highly context dependent and that participants need to be more engaged in the choices they are claiming to make. Suggestions for future work include virtual reality or simulation methodologies which promote immersivity to ensure procedural validity whilst retaining safety. We also identify current guidelines contradict public viewpoint and argue public attitude needs to be better understood to give autonomous and automated vehicle manufacturers confidence in their design.

Lipid extraction from microbial and microalgae biomass requires the separation of oil-rich cells from the production media. This downstream procedure represents a major bottleneck in biodiesel production, increasing the cost of the final product. Flocculation is a rapid and cheap system for removing solid particles from a suspension. This natural characteristic is displayed by some microorganisms due to the presence of lectin-like proteins (called flocculins/adhesins) in the cell wall. In this work, we showed, for the first time, that the heterologous expression of the adhesin Cfl1p endows the oleaginous species

In cross-sectional analyses, early institutional care is associated with shorter stature but not obesity during puberty in children adopted into US families. We examined whether shorter stature and leaner body composition in youth adopted internationally from institutions would continue as puberty progressed. We also examined whether current psychosocial stress would moderate the association between early institutional deprivation and growth during adolescence. Using an accelerated longitudinal design and linear mixed-effects models, we examined the height and body mass index (BMI) of 132 previously institutionalized (PI) and 176 nonadopted (NA) youth. We examined youth aged 7-15 at the beginning of the study three times across 2 years. Nurses assessed anthropometrics and pubertal status. Current psychosocial stress was measured using the Youth Life Stress Interview. Our results indicated that PI youth remained shorter and leaner across three assessments than NA youth. However, age-and-sex-adjusted BMI increased faster in PI youth. Psychosocial stress during puberty predicted greater age-and-sex-adjusted BMI, but this effect did not differ by group. The gap in BMI but not height appears to close between PI and NA youth. Higher psychosocial stress was associated with higher BMI during puberty.

The biosynthesis of dopamine (DA) from L-tyrosine as starting material is an excellent yet challenging strategy. Here we developed a versatile, multi-enzymatic platform for the biocatalytic preparation of DA in a continuous mode with excellent conversion (90 %) and reaction time (45 min). The system exploits the immobilization of a decarboxylase from Bacillus pumilis (Fdc) and a tyrosinase from Agaricus bisporus (Tyr), which were combined to mimic the in-vivo synthesis of DA (both primary and secondary metabolisms) giving rise to an efficient strategy with a considerable reduction of process associated costs and environmental impact. To enhance the system automation, an in-line purification via catch-and-release procedure was added.

Background: Microbial lipids have been emerging as a sustainable alternative to vegetable oils and animal fat to produce biodiesel and industrial relevant chemicals. The use of wastes for microbial processes can represent a way for upgrading low value feedstock to high value products, addressing one of the main goals of circular economy, the reduction of wastes by recycling. Two oleaginous yeasts, Rhodosporidiobolus azoricus and Cutaneotrichosporon oleaginosum, were used in this study to demonstrate the feasibility of the proposed approach. Results: In this study wastes from industrial food processing, as pumpkin peels and syrup from candied fruits manufacture, were used for yeast cultivation and for lipids production. Evaluation of growth and sugar consumption revealed marked differences between the yeasts in capacity to utilize the main sugars present in the feedstock. In particular, we observed an unexpected limitation in glucose metabolism on mineral defined media by R. azoricus. Both species showed ability to grow and accumulate lipids on media exclusively composed by undiluted pumpkin peel hydrolysate, and R. azoricus was the best performing. By a two-stage process carried out in bioreactor, this species reached a biomass concentration of 45 g/L (dry weight) containing 55% of lipids, corresponding to a lipid concentration of 24 g/L, with a productivity of 0.26 g/L/h and yield of 0.24 g lipids per g of utilized sugar. Conclusions: Wastes from industrial food processing were sufficient to completely support yeast growth and to induce lipid accumulation. This study provides strong evidence that the concept of valorisation through the production of lipids from the metabolism of nutrients present in agro-industrial wastes by oleaginous yeasts is promising for implementation of biotechnological processes in a circular economy contest.

Tese de doutoramento em Biologia, A utilização sustentável e eficiente de hidrolisados lignocelulósicos por leveduras em biorefinarias, requer o consumo simultâneo de todos os açúcares presentes nesta matéria-prima, nomeadamente, hexoses e pentoses. Este aspeto está, no entanto, limitado pelo baixo número de transportadores específicos para pentoses conhecidos e pela reduzida taxa de consumo de pentoses pela levedura quando a glucose está presente. Kluyveromyces marxianus é uma levedura não convencional que tem atraído atenção considerável devido às suas características com grande interesse industrial, como a capacidade de assimilação natural de pentoses, elevadas termotolerância e taxa de crescimento. Neste contexto, o principal objetivo da presente tese foi estudar o transporte de pentoses em K. marxianus, de forma a selecionar e modificar um transportador que permitisse o co-consumo de glucose e xilose para a aplicação em biorefinarias. A fim de identificar novos transportadores de pentoses, foi criada uma estirpe de K. marxianus, na qual foram eliminados 12 genes que codificavam transportadores da superfamíia MFS (major facilitator superfamily) e que não apresentava crescimento em pentoses (xilose ou arabinose). Usando esta plataforma ΔPT, identificamos vários transportadores de K. marxianus que recuperaram a capacidade da estirpe utilizar xilose e/ou arabinose. Estes transportadores foram caracterizados quanto à cinética de transporte de pentose e glucose utilizando açúcares marcados com 14C. Um destes transportadores mostrou uma alta afinidade tanto para a xilose como para a glucose, embora a afinidade para a glucose ainda fosse 150 vezes maior do que para a xilose. Usando em análise in silico foram selecionamos aminoácidos-alvo deste transportador para mutagénese dirigida, numa tentativa de aumentar a afinidade para a xilose e diminuir o transporte de glucose. Vários mutantes foram construídos e caracterizados por ensaios radioativos e por avaliação do seu crescimento em misturas de açúcares. Um destes mutantes apresentou uma afinidade mais reduzida para glucose aumentando, simultaneamente a sua afinidade para a xilose, mostrando-se muito promissor. A reprogramação bem sucedida deste transportador foi usada para facilitar o co-consumo eficiente de hexoses e pentoses numa nova estirpe de K. marxianus, encurtando significativamente o tempo de fermentação em bioreatores com misturas destes açúcares., Sustainable and efficient use of lignocellulosic hydrolysates in yeast-based biorefineries requires the simultaneous consumption of all the sugars present in this raw material, hexoses and pentoses. This represents a key bottleneck because of the low number of specific pentose transporters identified and the slow rate of pentose uptake into the yeast cell when glucose is present. Kluyveromyces marxianus is a non-conventional yeast that has attracted considerable attention due to its traits of industrial interest, like the ability of naturally assimilating pentoses, high thermotolerance and fast growth rate. In this thesis, the main goal was to investigate and engineer pentose uptake in K. marxianus to obtain a transporter that would allow co-consumption of glucose and xylose for the application in biorefineries. In order to identify novel pentose transporters, a K. marxianus screening platform (ΔPT) was constructed by deleting 12 genes that encoded transporters of the major facilitator superfamily (MFS). Using this ΔPT platform, which was unable to grow on pentoses, we identified several native K. marxianus transporters that recovered the native strain’s ability to grow on either xylose and/or arabinose. Kinetic studies on the most promising candidates using 14C-labelled sugars were carried on. One member of these transporters showed high affinity for both xylose and glucose, though the affinity for glucose was still 150-fold higher than for xylose. Using in silico analysis we selected target amino acids of this transporter for site-directed mutagenesis in an attempt to convert it into a specific xylose transporter. Several mutants were constructed and characterised by radioactive uptake and growth assays in bioreactors on mixture of sugars. One of these mutants decreased its ability to transport glucose but still transported xylose with even higher affinity kinetics. The successful reprogramming of this transporter to increase its preference for xylose over glucose was used to facilitate efficient co-consumption of hexose and pentose sugars in a novel K. marxianus strain, significantly shortening the time of the whole process., I gratefully acknowledge the financial support of the YEASTDOC ITN program, funded by the European Union’s Horizon 2020 Research and Innovation programme under the Marie Skłodowska-Curie Grant Agreement No. 764927.

This proof-of-concept study will determine whether a standard laboratory protocol used to induce a cortisol response will continue to work in an online data collection platform. If so, the study will also be able to examine whether the stress they and their family are under during this pandemic and their tendency toward anxiety, are related to the likelihood or magnitude of a cortisol response.

Methodology for obtaining hair samples for cortisol concentration (HCC) in a complete remote manner, from both adults and children. Materials and instructions are shipped to participants, samples are returned by mail.

Assisted and automated driving functions are increasingly deployed to support improved safety, efficiency, and enhance driver experience. However, there are still key technical challenges that need to be overcome, such as the degradation of perception sensor data due to noise factors. The quality of data being generated by sensors can directly impact the planning and control of the vehicle, which can affect the vehicle safety. This work builds on a recently proposed framework, analysing noise factors on automotive LiDAR sensors, and deploys it to camera sensors, focusing on the specific disturbed sensor outputs via a detailed analysis and classification of automotive camera specific noise sources (30 noise factors are identified and classified in this work). Moreover, the noise factor analysis has recognised two omnipresent and independent noise factors (i.e. obstruction and windshield distortion). These noise factors have been modelled to generate noisy camera data; their impact on the perception step, based on deep neural networks, has been evaluated when the noise factors are applied independently and simultaneously. It is demonstrated that the performance degradation from the combination of noise factors is not simply the accumulated performance degradation from each single factor, which raises the importance of including the simultaneous analysis of multiple noise factors. Thus, the framework can support and enhance the use of simulation for development and testing of automated vehicles through careful consideration of the noise factors affecting camera data.

With the aim of developing bioprocesses for waste valorization and a reduced water footprint, we optimized a two-step fermentation process that employs the oleaginous yeast Cutaneotrichosporon oleaginosus for the production of oil from liquid cheese whey permeate. For the first step, the addition of urea as a cost-effective nitrogen source allowed an increase in yeast biomass production. In the second step, a syrup from candied fruit processing, another food waste supplied as carbon feeding, triggered lipid accumulation. Consequently, yeast lipids were produced at a final concentration and productivity of 38 g/L and 0.57 g/L/h respectively, which are among the highest reported values. Through this strategy, based on the valorization of liquid food wastes (WP and mango syrup) and by recovering not only nutritional compounds but also the water necessary for yeast growth and lipid production, we addressed one of the main goals of the circular economy. In addition, we set up an accurate and fast-flow cytometer method to quantify the lipid content, avoiding the extraction step and the use of solvents. This can represent an analytical improvement to screening lipids in different yeast strains and to monitoring the process at the single-cell level.

The global Connected and Autonomous Mobility industry is growing at a rapid pace. To ensure the successful adoption of connected automated mobility solutions, their safety, reliability and hence the public acceptance are paramount. It is widely known that in order to demonstrate that L3+ automated systems are safer with respect to human drivers, upwards of several millions of miles need to be driven. The only way to efficiently achieve this amount of tests in a timely manner is by using simulations and high fidelity virtual environments. Two key components of being able to test an automated system in a synthetic environment are validated sensor models and noise models for each sensor technology. In fact, the sensors are the element feeding information into the system in order to enable it to safely plan the trajectory and navigate. In this paper, we propose an innovative real-time LiDAR sensor model based on beam propagation and a probabilistic rain model, taking into account raindrop distribution and size. The model can seamlessly run in real-time, synchronised with the visual rendering, in immersive driving simulators, such as the WMG 3xD simulator. The models are developed using Unreal engine, therefore demonstrating that gaming technology can be merged with the Automated Vehicles (AVs) simulation toolchain for the creation and visualization of high fidelity scenarios and for AV accurate testing. This work can be extended to add more sensors and more noise factors or cyberattacks in real-time simulations.

The target sits at the core of each facility for the production of radioactive ion beams for nuclear physics research. The materials which constitutes it must withstand extremes conditions of temperature and pressure, being bombarded by intense beams of light particles for several days. This is particularly important in high-power facilities such as SPES (Selective Production of Exotic Species) in which the targets are subjected to strong thermal gradients. Accurate choice and design of materials are therefore crucial. On recent years, several studies have been carried out in the framework of the SPES target research and development. An overview of recently exploited production techniques and a selection of synthesized materials are presented.