380 research outputs found

    Hybrid Vehicles as a Transition for Full E-Mobility Achievement in Positive Energy Districts: Comparative Assessment of Real-Driving Emissions

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    Air pollution is a major concern, particularly in developing countries. Road transport and mobile sources are considered the root causes of air pollutants. With the implementation of zero-carbon and zero-energy concepts at the district scale, cities can make great strides towards sustainable development. Urban planning schemes are moving from mere building solutions to the larger positive energy district (PED) scale. Alongside other technology systems in PEDs, increased uptake of electro-mobility solutions can play an important role in CO2 mitigation at the district level. This paper aims to quantify the exhaust emissions of six conventional and two fully hybrid vehicles using a portable emission measurement system (PEMS) in real driving conditions. The fuel consumption and exhaust pollutants of the conventional and hybrid vehicles were compared in four different urban and highway driving routes during autumn 2019 in Iran. The results showed that hybrid vehicles presented lower fuel consumption and produced relatively lower exhaust emissions. The conventional group’s fuel consumption (CO2 emissions) was 11%, 41% higher than that of the hy-brids. In addition, the hybrid vehicles showed much better fuel economy in urban routes, which is beneficial for PEDs. Micro-trip analysis showed that although conventional vehicles emitted more CO2 at lower speeds, the hybrids showed a lower amount of CO2. Moreover, in conventional vehi-cles, NOx emissions showed an increasing trend with vehicle speed, while no decisive trend was found for NOx emissions versus vehicle speed in hybrid vehicles

    A ‘hot’ cocktail: the multiple layers of thermomemory in plants

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    Heat stress (HS) caused by above-optimal temperatures adversely affects plants’ growth and development and diminishes crop yields. In natural and agricultural environments, these stresses are often transient but recurrent and may progressively increase in severity over time. In addition to the inherent ability to cope with a single HS event, plants have evolved mechanisms that enhance their capacity to survive and reproduce under such conditions. This involves the establishment of a molecular ‘thermomemory’ after moderate HS that allows them to withstand a later — and possibly more extreme — HS event. Here, I summarize the current understanding of the molecular and biochemical mechanisms underlying thermomemory across multiple cellular levels and discuss aspects that require further attention.Plant science

    JUNGBRUNNEN1 confers drought tolerance downstream of the HD-Zip I Transcription factor AtHB13

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    Low water availability is the major environmental factor limiting growth and productivity of plants and crops and is therefore considered of high importance for agriculture affected by climate change. Identifying regulatory components controlling the response and tolerance to drought stress is thus of major importance. The NAC transcription factor (TF) JUNGBRUNNEN1 (JUB1) from Arabidopsis thaliana extends leaf longevity under non-stress growth conditions, lowers cellular hydrogen peroxide (H2O2) level, and enhances tolerance against heat stress and salinity. Here, we additionally find that JUB1 strongly increases tolerance to drought stress in Arabidopsis when expressed from both, a constitutive (CaMV 35S) and an abiotic stress-induced (RD29A) promoter. Employing a yeast one-hybrid screen we identified HD-Zip class I TF AtHB13 as an upstream regulator of JUB1. AtHB13 has previously been reported to act as a positive regulator of drought tolerance. AtHB13 and JUB1 thereby establish a joint drought stress control module.Fil: Ebrahimian Motlagh, Saghar. University of Potsdam; Alemania. Max Planck Institute of Molecular Plant Physiology; AlemaniaFil: Ribone, Pamela Anahí. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Thirumalaikumar, Venkatesh P.. Max Planck Institute of Molecular Plant Physiology; Alemania. University of Potsdam; AlemaniaFil: Allu, Annapurna D.. Max Planck Institute of Molecular Plant Physiology; Alemania. University of Potsdam; AlemaniaFil: Chan, Raquel Lia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Mueller Roeber, Bernd. University of Potsdam; Alemania. Max Planck Institute of Molecular Plant Physiology; AlemaniaFil: Balazadeh, Salma. University of Potsdam; Alemania. Max Planck Institute of Molecular Plant Physiology; Alemani

    EBE, an AP2/ERF Transcription Factor Highly Expressed in Proliferating Cells, Affects Shoot Architecture in Arabidopsis

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    We report about ERF BUD ENHANCER (EBE; At5g61890), a transcription factor that affects cell proliferation as well as axillary bud outgrowth and shoot branching in Arabidopsis (Arabidopsis thaliana). EBE encodes a member of the APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor superfamily; the gene is strongly expressed in proliferating cells and is rapidly and transiently up-regulated in axillary meristems upon main stem decapitation. Overexpression of EBE promotes cell proliferation in growing calli, while the opposite is observed in EBE-RNAi lines. EBE overexpression also stimulates axillary bud formation and outgrowth, while repressing it results in inhibition of bud growth. Global transcriptome analysis of estradiolinducible EBE overexpression lines revealed 48 EBE early-responsive genes, of which 14 were up-regulated and 34 were downregulated. EBE activates several genes involved in cell cycle regulation and dormancy breaking, including D-type cyclin CYCD3;3, transcription regulator DPa, and BRCA1-ASSOCIATED RING DOMAIN1. Among the down-regulated genes were DORMANCYASSOCIATED PROTEIN1 (AtDRM1), AtDRM1 homolog, MEDIATOR OF ABA-REGULATED DORMANCY1, and ZINC FINGER HOMEODOMAIN5. Our data indicate that the effect of EBE on shoot branching likely results from an activation of genes involved in cell cycle regulation and dormancy breaking.Fil: Mehrnia, Mohammad. Institut Max Planck Fur Molekulare Physiologie; AlemaniaFil: Balazadeh, Salma. Institut Max Planck Fur Molekulare Physiologie; Alemania. University of Potsdam. Institute of Biochemistry and Biology; AlemaniaFil: Zanor, María Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; Argentina. Institut Max Planck Fur Molekulare Physiologie; AlemaniaFil: Mueller Roeber, Bernd. Institut Max Planck Fur Molekulare Physiologie; Alemania. University of Potsdam, Institute of Biochemistry and Biology; Alemani

    Seismic Evaluation and Retrofit of Existing Concentrically Braced Steel Frames in Canada

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    RÉSUMÉ-Les nouveaux bâtiments en acier conçus selon les dispositions sismiques du Code national du bâtiment du Canada (CNB) (CRNC 2010) et les règles de calcul des charpentes en acier CSA S16 (CSA 2009) doivent résister en toute sécurité aux charges sismiques et développer une ductilité suffisante tout en maintenant une résistance et une rigidité adéquates. La conception parasismique avec les détails de conception spécifiques aux structures en acier a été introduite dans l'édition 1989 de la norme CSA. Ainsi, les structures conçues avant les années 1990 pourraient ne pas développer la réponse sismique ductile souhaitée. À ce jour, les recherches consacrées à l'évaluation sismique des cadres à contreventements concentriques existants conçus conformément aux codes des années 1980 sont très limitées au Canada.----------ABSTRACT-New steel buildings designed according to the seismic provisions of the National building Code of Canada (NBCC) (NRCC 2010) and the steel structures design standard CSA S16 (CSA 2009) are conceived to safely resist seismic loads and develop sufficient ductility while maintaining adequate strength and stiffness. The special seismic design and detailing requirements for steel structures were introduced in the 1989 edition of the CSA standard. Thus, the structures designed prior to 1990’s may not develop the ductile seismic response. To date, very limited research in Canada has been devoted into the seismic evaluation of existing concentrically braced frames designed in accordance with the 1980’s codes

    OCDaf: Ordered Causal Discovery with Autoregressive Flows

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    We propose OCDaf, a novel order-based method for learning causal graphs from observational data. We establish the identifiability of causal graphs within multivariate heteroscedastic noise models, a generalization of additive noise models that allow for non-constant noise variances. Drawing upon the structural similarities between these models and affine autoregressive normalizing flows, we introduce a continuous search algorithm to find causal structures. Our experiments demonstrate state-of-the-art performance across the Sachs and SynTReN benchmarks in Structural Hamming Distance (SHD) and Structural Intervention Distance (SID). Furthermore, we validate our identifiability theory across various parametric and nonparametric synthetic datasets and showcase superior performance compared to existing baselines

    Learning to Switch Between Machines and Humans

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    Reinforcement learning agents have been mostly developed and evaluated under the assumption that they will operate in a fully autonomous manner -- they will take all actions. In this work, our goal is to develop algorithms that, by learning to switch control between machine and human agents, allow existing reinforcement learning agents to operate under different automation levels. To this end, we first formally define the problem of learning to switch control among agents in a team via a 2-layer Markov decision process. Then, we develop an online learning algorithm that uses upper confidence bounds on the agents' policies and the environment's transition probabilities to find a sequence of switching policies. We prove that the total regret of our algorithm with respect to the optimal switching policy is sublinear in the number of learning steps. Moreover, we also show that our algorithm can be used to find multiple sequences of switching policies across several independent teams of agents operating in similar environments, where it greatly benefits from maintaining shared confidence bounds for the environments' transition probabilities. Simulation experiments in obstacle avoidance in a semi-autonomous driving scenario illustrate our theoretical findings and demonstrate that, by exploiting the specific structure of the problem, our proposed algorithm is superior to problem-agnostic algorithms.Comment: Added support for unknown transition probabilities and multiple team
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