| 1. |
- Metcalfe, Daniel B., et al.
(författare)
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Impacts of experimentally imposed drought on leaf respiration and morphology in an Amazon rain forest
- 2010
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Ingår i: Functional Ecology. - : Wiley. - 0269-8463 .- 1365-2435. ; 24:3, s. 524-533
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Tidskriftsartikel (refereegranskat)abstract
- P>1. The Amazon region may experience increasing moisture limitation over this century. Leaf dark respiration (R) is a key component of the Amazon rain forest carbon (C) cycle, but relatively little is known about its sensitivity to drought. 2. Here, we present measurements of R standardized to 25 degrees C and leaf morphology from different canopy heights over 5 years at a rain forest subject to a large-scale through-fall reduction (TFR) experiment, and nearby, unmodified Control forest, at the Caxiuana reserve in the eastern Amazon. 3. In all five post-treatment measurement campaigns, mean R at 25 degrees C was elevated in the TFR forest compared to the Control forest experiencing normal rainfall. After 5 years of the TFR treatment, R per unit leaf area and mass had increased by 65% and 42%, respectively, relative to pre-treatment means. In contrast, leaf area index (L) in the TFR forest was consistently lower than the Control, falling by 23% compared to the pre-treatment mean, largely because of a decline in specific leaf area (S). 4. The consistent and significant effects of the TFR treatment on R, L and S suggest that severe drought events in the Amazon, of the kind that may occur more frequently in future, could cause a substantial increase in canopy carbon dioxide emissions from this ecosystem to the atmosphere.
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| 2. |
- Archetti, Joao A. G., et al.
(författare)
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Hardware-in-the-Loop Volt-Watt and Volt-VAr Control for Distribution Systems with High Penetration of Renewables
- 2023
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Ingår i: Journal of Control Automation and Electrical Systems. - : Springer Nature. - 2195-3880 .- 2195-3899. ; 34:1, s. 177-188
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Tidskriftsartikel (refereegranskat)abstract
- This work aims to validate in control hardware in the loop (CHIL) simulations new voltage profile control strategies in distribution systems with different levels of photovoltaic penetration. The proposed control is implemented through intelligent inverters with control functions that act through voltage sensitivity. The Volt-VAr (V-V) and Volt-Watt (V-W) functions act in the local voltage control being implemented in a complementary way. The simulations are performed in real time, using the real-time digital simulator. Residential load profiles, solar irradiance and temperature curves are discretized hourly over a daily period, with the intention of making the emulation more realistic. Voltage source converters were implemented in RSCAD software. The contribution of this article points to the performance of the Volt-Watt (V-W) control function in single-stage inverters, which allows the maximum generation of instantaneous active power, acting directly on the maximum power point tracking algorithm, this strategy being validated by the CHIL simulation. The results show that the Volt-VAr and Volt-Watt control functions, acting at different levels of photovoltaic penetration, were effective in preventing the voltage profiles from violating the critical level imposed by the regulatory standard. Leading to the conclusion that its implementation directly in photovoltaic inverters entails a low cost and a complementary solution for the new challenges of electrical systems.
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| 3. |
- Archetti, Joao Antonio Guedes, et al.
(författare)
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Real time validation of a control system for microgrids with distributed generation and storage resources
- 2023
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Ingår i: Electric power systems research. - : Elsevier. - 0378-7796 .- 1873-2046. ; 223
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Tidskriftsartikel (refereegranskat)abstract
- Faced with a scenario in which the increase in renewable energy generated near consumer centers can cause problems for the operation of the electrical network, the present work proposes a real-time simulation model for automation and control systems of electrical distribution networks with microgrids, distributed generation, and storage resources. The proposed model consists of a hardware-in-the-loop control with the aid of a simulation tool in conjunction with a Real-Time Digital Simulator (RTDS) and considers the dynamic behavior of switched elements and inverters. A communication platform using TCP/IP protocol between RTDS (power system) and MatLab/Simulink (optimization algorithms) allows the operation of the network in grid-connected and islanded mode, guaranteeing the computational time for experimental implementation. For the first mode, an algorithm is proposed to solve an optimal dispatch energy storage system problem. Second mode, an algorithm is proposed to solve a load shedding problem. The objective is to operate the microgrids optimally and evaluate the performance of a storage system based on real data from the state of Parana, in Brazil. Results show that the optimization algorithms are experimentally applicable, obtaining reasonable computational time to find optimal solutions and an assertive decision-making to meet the objectives. Thus, the proposed framework is a potential tool to validate algorithms for active management of microgrids in real-time simulation.
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| 4. |
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| 5. |
- Bonilla, Cesar, et al.
(författare)
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Collider signatures of vector-like fermions from a flavor symmetric model
- 2022
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; 2022:1
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Tidskriftsartikel (refereegranskat)abstract
- We propose a model with two Higgs doublets and several SU(2) scalar singlets with a global non-Abelian flavor symmetry Q6× Z2. This discrete group accounts for the observed pattern of fermion masses and mixing angles after spontaneous symmetry breaking. In this scenario only the third generation of fermions get their masses as in the Standard Model (SM). The masses of the remaining fermions are generated through a seesaw-like mechanism. To that end, the matter content of the model is enlarged by introducing electrically charged vector-like fermions (VLFs), right handed Majorana neutrinos and several SM scalar singlets. Here we study the processes involving VLFs that are within the reach of the Large Hadron Collider (LHC). We perform collider studies for vector-like leptons (VLLs) and vector-like quarks (VLQs), focusing on double production channels for both cases, while for VLLs single production topologies are also included. Utilizing genetic algorithms for neural network optimization, we determine the statistical significance for a hypothetical discovery at future LHC runs. In particular, we show that we can not safely exclude VLLs for masses greater than 200 GeV. For VLQ’s in our model, we show that we can probe their masses up to 3.8 TeV, if we take only into account the high-luminosity phase of the LHC. Considering Run-III luminosities, we can also exclude VLQs for masses up to 3.4 TeV. We also show how the model with predicted VLL masses accommodates the muon anomalous magnetic moment.
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| 6. |
- Bonilla, Cesar, et al.
(författare)
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Gravitational waves from a scotogenic two-loop neutrino mass model
- 2024
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Ingår i: Physical Review D. - 2470-0010. ; 109:9
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Tidskriftsartikel (refereegranskat)abstract
- We propose a framework to account for neutrino masses at the two-loop level. This mechanism introduces new scalars and Majorana fermions to the Standard Model. It assumes the existence of a global U(1)×Z2 symmetry which after partial breaking provides the stability of the dark matter candidates of the theory. The rich structure of the potential allows for the possibility of first-order phase transitions (FOPTs) in the early Universe which can lead to the generation of primordial gravitational waves. Taking into account relevant constraints from lepton flavor violation, neutrino physics, as well as the trilinear Higgs couplings at next-to-leading order accuracy, we have found a wide range of possible FOPTs which are strong enough to be probed at the proposed gravitational-wave interferometer experiments such as LISA.
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| 7. |
- Cachim, Afonso, et al.
(författare)
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Measuring adherence to inhaled control medication in patients with asthma : Comparison among an asthma app, patient self-report and physician assessment
- 2023
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Ingår i: Clinical and Translational Allergy. - : John Wiley & Sons. - 2045-7022. ; 13:2
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundPrevious studies have demonstrated the feasibility of using an asthma app to support medication management and adherence but failed to compare with other measures currently used in clinical practice. However, in a clinical setting, any additional adherence measurement must be evaluated in the context of both the patient and physician perspectives so that it can also help improve the process of shared decision making. Thus, we aimed to compare different measures of adherence to asthma control inhalers in clinical practice, namely through an app, patient self-report and physician assessment.MethodsThis study is a secondary analysis of three prospective multicentre observational studies with patients (≥13 years old) with persistent asthma recruited from 61 primary and secondary care centres in Portugal. Patients were invited to use the InspirerMundi app and register their inhaled medication. Adherence was measured by the app as the number of doses taken divided by the number of doses scheduled each day and two time points were considered for analysis: 1-week and 1-month. At baseline, patients and physicians independently assessed adherence to asthma control inhalers during the previous week using a Visual Analogue Scale (VAS 0–100).ResultsA total of 193 patients (72% female; median [P25–P75] age 28 [19–41] years old) were included in the analysis. Adherence measured by the app was lower (1 week: 31 [0–71]%; 1 month: 18 [0–48]%) than patient self-report (80 [60–95]) and physician assessment (82 [51–94]) (p < 0.001). A negligible non-significant correlation was found between the app and subjective measurements (ρ 0.118–0.156, p > 0.05). There was a moderate correlation between patient self-report and physician assessment (ρ = 0.596, p < 0.001).ConclusionsAdherence measured by the app was lower than that reported by the patient or the physician. This was expected as objective measurements are commonly lower than subjective evaluations, which tend to overestimate adherence. Nevertheless, the low adherence measured by the app may also be influenced by the use of the app itself and this needs to be considered in future studies.
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| 8. |
- Chari, Arpita, 1986, et al.
(författare)
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Dynamic capabilities for circular manufacturing supply chains-Exploring the role of Industry 4.0 and resilience
- 2022
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Ingår i: Business Strategy and the Environment. - : Wiley. - 1099-0836 .- 0964-4733. ; 31:5, s. 2500-2517
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Tidskriftsartikel (refereegranskat)abstract
- An organisation's sustainability performance is influenced by its capabilities (skills, resources and competences) which in turn affects the performance of its entire supply chain. However, recent research has not sufficiently explored the convergence of dynamic capabilities, circular economy, resilience and Industry 4.0 concepts for manufacturing supply chains. Therefore, this study aims to identify how dynamic capabilities theory can enable circular and resilient supply chains. A qualitative research process was deployed in three stages: literature review, European project and nine expert interviews. Key investigative variables were used to identify capabilities used in manufacturing, and five research propositions were developed to address the gaps found in literature. The empirical data helped reveal challenges to circular economy implementation and validate the literature findings. The main contributions include a dynamic capabilities model, a causal relationship model and five research propositions for circular economy implementation.
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| 9. |
- Correia, Carlos M., et al.
(författare)
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Ultraviolet-B radiation and nitrogen affect nutrient concentrations and the amount of nutrients acquired by above-ground organs of maize
- 2012
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Ingår i: The Scientific World Journal. - : Hindawi Limited. - 2356-6140 .- 1537-744X. ; 2012
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Tidskriftsartikel (refereegranskat)abstract
- UV-B radiation effects on nutrient concentrations in above-ground organs of maize were investigated at silking and maturity at different levels of applied nitrogen under field conditions. The experiment simulated a 20% stratospheric ozone depletion over Portugal. At silking, UV-B increased N, K, Ca, and Zn concentrations, whereas at maturity Ca,Mg, Zn, and Cu increased and N, P and Mn decreased in some plant organs. Generally, at maturity, N, Ca, Cu, and Mn were lower, while P, K, and Zn concentrations in stems and nitrogen-use efficiency (NUE) were higher in N-starved plants. UV-B and N effects on shoot dry biomass were more pronounced than on nutrient concentrations. Nutrient uptake decreased under high UV-B and increased with increasing N application, mainly at maturity harvest. Significant interactions UV-B x N were observed for NUE and for concentration and mass of some elements. For instance, under enhanced UV-B, N, Cu, Zn, and Mn concentrations decreased in leaves, except on Nstressed plants, whereas they were less affected by N nutrition. In order to minimize nutritional, economical, and environmental negative consequences, fertiliser recommendations based on element concentration or yield goals may need to be adjusted.
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| 10. |
- Costa, Fabiano, et al.
(författare)
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Acetic acid-induced pain elicits stress-, and camouflage-related responses in zebrafish: Modulatory effects of opioidergic drugs on neurobehavioral phenotypes
- 2023
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Ingår i: Comparative Biochemistry and Physiology - Part C: Toxicology & Pharmacology. - 1532-0456. ; 270
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Tidskriftsartikel (refereegranskat)abstract
- While pain results from the activation of nociceptors following noxious stimuli, mounting evidence links pain- and stress-related responses in mammals. In zebrafish, the activation of hypothalamic-pituitary-interrenal (HPI) axis may also regulate body pigmentation (the camouflage response). Here, we aimed to investigate a putative relationship between pain-, stress-, and camouflage-related parameters in adult zebrafish. To answer this question, we assessed whether intraperitoneal acetic acid injection can activate the HPI axis, measuring whole-body cortisol and the camouflage response as physiological endpoints in the presence or absence of morphine or naloxone, an opioid antagonist. Acetic acid induced a stereotypic circling behavior in the top of the tank, accompanied by abdominal writhing-like response, a specific phenotype that reflects local nociceptive effect. Both whole-body cortisol levels and camouflage response increased in the acetic acid group, while morphine prevented these responses, and naloxone antagonized morphine-induced effects. Moreover, we observed positive correlations between representative behavioral, physiological and skin coloration endpoints, and a “pain index” was proposed to summarize phenotypic profile of zebrafish under different pharmacological manipulations. Collectively, these findings suggest a coordinated activation of pain, camouflage- and stress-related pathways following acetic acid injection in zebrafish. Our data also support that camouflage response represents a novel and relevant biomarker for future probing pain and stress neurobiology, with a robust sensitivity to opioidergic drugs.
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| 11. |
- de Barros, Thiago Ribeiro, et al.
(författare)
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Optimization algorithm associated with local and coordinated controls of distributed energy resources to meet technical and economic criteria
- 2024
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Ingår i: Electric power systems research. - : Elsevier. - 0378-7796 .- 1873-2046. ; 226
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Tidskriftsartikel (refereegranskat)abstract
- The present work proposes the development of a simulation platform that integrates the PSCAD software with python language, capable of portraying realistic and dynamic characteristics of the operation of an electrical system with high insertion of DERs. This work considers a scenario with high insertion of alternative sources, which are characterized by intermittent conditions of generation and consumption, therefore causing technical-economic challenges in the operation of the network. In this way, an electrical network will be created with photovoltaic systems, electric vehicles and batterys, in addition to local, coordinated and optimization controls. Local and coordinated controls act on network undervoltage and overvoltage problems. The optimized control, created in Python and based on a Predictive Control Model, determines the optimal operating curve for the batterys, reducing the energy cost of the system, being activated when the network does not present technical problems. Results showed a reduction of more than 16% in the energy cost of the network when enabling the optimized control, keeping the voltage profiles within regulatory limits. Thus, the proposed platform manages to carry out the technical-economic monitoring of the network, becoming a promising tool for the creation of active network management algorithms in dynamic simulations.
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| 12. |
- Donis, Daphne, et al.
(författare)
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Stratification strength and light climate explain variation in chlorophyll a at the continental scale in a European multilake survey in a heatwave summer
- 2021
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Ingår i: Limnology and Oceanography. - : John Wiley & Sons. - 0024-3590 .- 1939-5590. ; 66:12, s. 4314-4333
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Tidskriftsartikel (refereegranskat)abstract
- To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phosphorus [TP] = 0.06 and total nitrogen [TN] = 0.7 mg L-1), and its subsets (2 depth types and 3 climatic zones), show that light climate and stratification strength were the most significant explanatory variables for chlorophyll a (Chl a) variance. TN was a significant predictor for phytoplankton biomass for shallow and continental lakes, while TP never appeared as an explanatory variable, suggesting that under high TP, light, which partially controls stratification strength, becomes limiting for phytoplankton development. Mediterranean lakes were the warmest yet most weakly stratified and had significantly less Chl a than Boreal lakes, where the temperature anomaly from the long-term average, during a summer heatwave was the highest (+4 degrees C) and showed a significant, exponential relationship with stratification strength. This European survey represents a summer snapshot of phytoplankton biomass and its drivers, and lends support that light and stratification metrics, which are both affected by climate change, are better predictors for phytoplankton biomass in nutrient-rich lakes than nutrient concentrations and surface temperature.
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| 13. |
- Ferreira, P. M., et al.
(författare)
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Collider phenomenology of new neutral scalars in a flavored multi-Higgs model
- 2023
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Ingår i: Physical Review D. - 2470-0010. ; 107:9
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we propose and explore for the first time a new collider signature of heavy neutral scalars typically found in many distinct classes of multi-Higgs models. This signature, particularly relevant in the context of the Large Hadron Collider (LHC) measurements, is based on a topology with two charged leptons and four jets arising from first and second generation quarks. As an important benchmark scenario of the multi-Higgs models, we focus on a recently proposed Branco-Grimus-Lavoura (BGL) type model enhanced with an Abelian U(1) flavor symmetry and featuring an additional sector of right-handed neutrinos. We discuss how kinematics of the scalar fields in this model can be used to efficiently separate the signal from the dominant backgrounds and explore the discovery potential of the new heavy scalars in the forthcoming LHC runs. The proposed method can be applied for analysis of the statistical significance of heavy scalars' production at the LHC and future colliders in any multi-Higgs model.
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| 14. |
- Ferreira, P. M., et al.
(författare)
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Phenomenology of a flavored multiscalar Branco-Grimus-Lavoura-like model with three generations of massive neutrinos
- 2022
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Ingår i: Physical Review D. - 2470-0010. ; 106:7
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present several possible anomaly free implementations of the Branco-Grimus-Lavoura (BGL) model with two Higgs doublets and one singlet scalar. The model also includes three generations of massive neutrinos that get their mass via a type-I seesaw mechanism. A particular anomaly free realization, which we dub νBGL-1 scenario, is subjected to an extensive phenomenological analysis, from the perspective of flavor physics and collider phenomenology.
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| 15. |
- Floriddia, Elisa M., et al.
(författare)
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Distinct oligodendrocyte populations have spatial preference and different responses to spinal cord injury
- 2020
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Mature oligodendrocytes (MOLs) show transcriptional heterogeneity, the functional consequences of which are unclear. MOL heterogeneity might correlate with the local environment or their interactions with different neuron types. Here, we show that distinct MOL populations have spatial preference in the mammalian central nervous system (CNS). We found that MOL type 2 (MOL2) is enriched in the spinal cord when compared to the brain, while MOL types 5 and 6 (MOL5/6) increase their contribution to the OL lineage with age in all analyzed regions. MOL2 and MOL5/6 also have distinct spatial preference in the spinal cord regions where motor and sensory tracts run. OL progenitor cells (OPCs) are not specified into distinct MOL populations during development, excluding a major contribution of OPC intrinsic mechanisms determining MOL heterogeneity. In disease, MOL2 and MOL5/6 present different susceptibility during the chronic phase following traumatic spinal cord injury. Our results demonstrate that the distinct MOL populations have different spatial preference and different responses to disease.
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| 16. |
- Freitas, Felipe F., et al.
(författare)
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Interplay between flavor anomalies and neutrino properties
- 2023
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Ingår i: Physical Review D. - 2470-0010. ; 108:11
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Tidskriftsartikel (refereegranskat)abstract
- A minimal extension of the Standard Model (SM) featuring two scalar leptoquarks, an SU(2) doublet with hypercharge 1/6 and a singlet with hypercharge 1/3, is proposed as an economical benchmark model for studies of an interplay between flavor physics and properties of the neutrino sector. The presence of such type of leptoquarks radiatively generates neutrino masses and offers a simultaneous explanation for the current B-physics anomalies involving b→cℓνℓ decays. The model can also accommodate both the muon magnetic moment and the recently reported W-mass anomalies, while complying with the most stringent lepton flavor-violating observables.
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| 17. |
- Freitas, Felipe F., et al.
(författare)
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Phenomenology at the large hadron collider with deep learning : the case of vector-like quarks decaying to light jets
- 2022
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 82:9
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we continue our exploration of TeV-scale vector-like fermion signatures inspired by a Grand Unification scenario based on the trinification gauge group. A particular focus is given to pair-production topologies of vector-like quarks (VLQs) at the LHC, in a multi-jet plus a charged lepton and a missing energy signature. We employ Deep Learning methods and techniques based in evolutive algorithms that optimize hyper-parameters in the neural network construction, whose objective is to maximise the Asimov estimate for distinct VLQ masses. In this article, we consider the implications of an innovative approach by simultaneously combining detector images (also known as jet images) and tabular data containing kinematic information from the final states. With this technique we are able to exclude VLQs, that are specific for the considered model, up to a mass of 800 GeV in both the high-luminosity the Run-III phases of the LHC programme.
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| 18. |
- Freitas, Felipe F., et al.
(författare)
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Phenomenology of vector-like leptons with Deep Learning at the Large Hadron Collider
- 2021
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; 2021:1
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, a model inspired by Grand Unification principles featuring three generations of vector-like fermions, new Higgs doublets and a rich neutrino sector at the low scale is presented. Using the state-of-the-art Deep Learning techniques we perform the first phenomenological analysis of this model focusing on the study of new charged vector-like leptons (VLLs) and their possible signatures at CERN’s Large Hadron Collider (LHC). In our numerical analysis we consider signal events for vector-boson fusion and VLL pair production topologies, both involving a final state containing a pair of charged leptons of different flavor and two sterile neutrinos that provide a missing energy. We also consider the case of VLL single production where, in addition to a pair of sterile neutrinos, the final state contains only one charged lepton. We propose a novel method to identify missing transverse energy vectors by comparing the detector response with Monte-Carlo simulated data. All calculated observables are provided as data sets for Deep Learning analysis, where a neural network is constructed, based on results obtained via an evolutive algorithm, whose objective is to maximise either the accuracy metric or the Asimov significance for different masses of the VLL. Taking into account the effect of the three analysed topologies, we have found that the combined significance for the observation of new VLLs at the high-luminosity LHC can range from 5.7σ, for a mass of 1.25 TeV, all the way up to 28σ if the VLL mass is 200 GeV. We have also shown that by the end of the LHC Run-III a 200 GeV VLL can be excluded with a confidence of 8.8 standard deviations. The results obtained show that our model can be probed well before the end of the LHC operations and, in particular, providing important phenomenological information to constrain the energy scale at which new gauge symmetries emergent from the considered Grand Unification picture can be manifest.
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| 19. |
- Gomes da Silva, Priscilla, et al.
(författare)
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Evidence of Air and Surface Contamination with SARS-CoV-2 in a Major Hospital in Portugal
- 2022
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Ingår i: International Journal of Environmental Research and Public Health. - : MDPI AG. - 1661-7827 .- 1660-4601. ; 19:1
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Tidskriftsartikel (refereegranskat)abstract
- As the third wave of the COVID-19 pandemic hit Portugal, it forced the country to reintroduce lockdown measures due to hospitals reaching their full capacities. Under these circumstances, environmental contamination by SARS-CoV-2 in different areas of one of Portugal’s major Hospitals was assessed between 21 January and 11 February 2021. Air samples (n = 44) were collected from eleven different areas of the Hospital (four COVID-19 and seven non-COVID-19 areas) using Coriolis® μ and Coriolis® Compact cyclone air sampling devices. Surface sampling was also performed (n = 17) on four areas (one COVID-19 and three non-COVID-19 areas). RNA extraction followed by a one-step RT-qPCR adapted for quantitative purposes were performed. Of the 44 air samples, two were positive for SARS-CoV-2 RNA (6575 copies/m3 and 6662.5 copies/m3, respectively). Of the 17 surface samples, three were positive for SARS-CoV-2 RNA (200.6 copies/cm2, 179.2 copies/cm2, and 201.7 copies/cm2, respectively). SARS-CoV-2 environmental contamination was found both in air and on surfaces in both COVID-19 and non-COVID-19 areas. Moreover, our results suggest that longer collection sessions are needed to detect point contaminations. This reinforces the need to remain cautious at all times, not only when in close contact with infected individuals. Hand hygiene and other standard transmission-prevention guidelines should be continuously followed to avoid nosocomial COVID-19.
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| 20. |
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| 21. |
- Gonçalves, João, et al.
(författare)
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Exploring mixed lepton-quark interactions in non-resonant leptoquark production at the LHC
- 2023
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; 2023:11
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Tidskriftsartikel (refereegranskat)abstract
- Searches for new physics (NP) at particle colliders typically involve multivariate analysis of kinematic distributions of final state particles produced in a decay of a hypothetical NP resonance. Since the pair-production cross-sections mediated by such resonances are strongly suppressed by the NP scale, this analysis becomes less relevant for NP searches for masses of the BSM resonance above 1 TeV. On the other hand, t-channel processes are less sensitive to the mass of the virtual mediator and therefore larger phase-space can be potentially probed as well as the couplings between the NP particles and the Standard Model fields. The fact that transitions between different generations of quarks and leptons may exist, the potential of the search presented in this article can be used, as a reference guide, to enlarge significantly the scope of searches performed at the LHC to flavour off-diagonal channels, in a theoretically consistent approach. In this work, we study non-resonant production of scalar leptoquarks which have been proposed in the literature to provide a potential avenue for radiative generation of neutrino masses, accommodating as well the existing flavour physics data. Final states involving just two muons at the LHC (μ + μ −), are used as a well-motivated case study.
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| 22. |
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| 23. |
- Leal, Marta, et al.
(författare)
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Double back-calculation approach to deal with input saturation in cascade control problems
- 2021
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Ingår i: CONTROLO 2020 - Proceedings of the 14th APCA International Conference on Automatic Control and Soft Computing. - Cham : Springer International Publishing. - 1876-1119 .- 1876-1100. - 9783030586522 ; 695 LNEE, s. 200-209
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Konferensbidrag (refereegranskat)abstract
- This paper presents a solution to the saturation problem in cascade control schemes. When cascade control approaches work in linear mode without saturation influence, important improvements can be achieved in industrial control loops. The effect of disturbances and/or nonlinear actuator behaviours on the main process variables can be considerably reduced. However, when saturation arises in the inner loop, these improvements cannot be reached and even sometimes the saturated cascade control scheme gives worse results than a single control loop. Thus, this work analyzes this situation and introduces an alternative solution to solve this problem and to reduce the impact of the saturation effect.
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| 24. |
- Mantzouki, Evanthia, et al.
(författare)
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Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins
- 2018
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Ingår i: Toxins. - : MDPI. - 2072-6651. ; 10:4
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Tidskriftsartikel (refereegranskat)abstract
- Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.
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| 25. |
- Martins Mattos, Marina, et al.
(författare)
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Analysis of voltage control using V2G technology to support low voltage distribution networks
- 2024
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Ingår i: IET Generation, Transmission & Distribution. - : John Wiley & Sons. - 1751-8687 .- 1751-8695. ; 18:6, s. 1133-1157
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Tidskriftsartikel (refereegranskat)abstract
- The decarbonization of the power generation and transport sector encourage the analysis of connection of distributed energy resources (DER), such as electric vehicles (EVs), to the electrical system, as well as the evaluation of their impact on smart cities. A better understanding of the negative impacts on the power systems will lead to propose mitigation measures and eventually revolutionize the way distributed generation works. This paper aims at modelling and evaluating the impact of EVs on a real distribution network. The energy system chosen operates at 60 Hz, 34.5 kV (medium voltage) and 0.208 kV (low voltage) and it is simulated using PSCAD/EMTDC. To reproduce realistic user consumption profiles, dynamic load profiles based on EV owners behaviour have been simulated. The vehicle-to-grid (V2G) technology is modelled to mitigate the impacts of high penetration of EVs by supporting the network from undervoltage. The results show the importance of active management in modern power systems, especially considering the increase in DER penetration expected for the coming years. This work shows the benefits of implementing V2G technology while highlighting the challenges involved in a real case. This paper aims at modelling and evaluating the impact of EVs on a real distribution network. The V2G technology is modelled to mitigate the impacts of high penetration of EVs by supporting the network from undervoltage. This work shows the benefits of implementing V2G technology while highlighting the challenges involved in a real case.image
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| 26. |
- Morais, António P., et al.
(författare)
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Deep learning searches for vector-like leptons at the LHC and electron/muon colliders
- 2023
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Ingår i: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 83:3
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Tidskriftsartikel (refereegranskat)abstract
- The discovery potential of both singlet and doublet vector-like leptons (VLLs) at the Large Hadron Collider (LHC) as well as at the not-so-far future muon and electron machines is explored. The focus is on a single production channel for LHC direct searches while double production signatures are proposed for the leptonic colliders. A Deep Learning algorithm to determine the discovery (or exclusion) statistical significance at the LHC is employed. While doublet VLLs can be probed up to masses of 1 TeV, their singlet counterparts have very low cross sections and can hardly be tested beyond a few hundreds of GeV at the LHC. This motivates a physics-case analysis in the context of leptonic colliders where one obtains larger cross sections in VLL double production channels, allowing to probe higher mass regimes otherwise inaccessible even to the LHC high-luminosity upgrade.
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| 27. |
- Pechorro, Pedro, et al.
(författare)
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Validation of the Youth Psychopathic Traits Inventory and Youth Psychopathic Traits Inventory : Short Version Among Incarcerated Juvenile Delinquents
- 2015
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Ingår i: Journal of Psychopathology and Behavioral Assessment. - : Springer. - 0882-2689 .- 1573-3505. ; 37:4, s. 576-586
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to examine the psychometric properties of the Youth Psychopathic Traits Inventory (YPI) and of the Youth Psychopathic Traits Inventory - Short version (YPI-S) among Portuguese juvenile delinquents within a forensic sample of 221 incarcerated males (ages 13-20 years). Confirmatory Factor Analysis supported the three-factor structure of the YPI and YPI-S, and the reliability of both instruments was good for the majority of subscales and factors. The YPI and YPI-S and their subscales showed good criterion, external, and divergent validity. That is, positive associations were found with a number of external criteria including Conduct Disorder, crime seriousness, and violent crimes. Total and subscale scores on both YPI versions were positively related to the Antisocial Process Screening Device, the Inventory of Callous-Unemotional Traits, and the Child and Adolescent Taxon Scale. Finally, both the YPI and YPI-S were mostly unrelated to the Social Anxiety Scale for Adolescents. Overall, the YPI-S presented less problems with reliability, but weaker relations to external correlates. These findings justify the use of the YPI and the YPI-S among incarcerated youths.
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| 28. |
- Pires, Ana Elisabete, et al.
(författare)
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The curious case of the Mesolithic Iberian dogs : An archaeogenetic study
- 2019
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Ingår i: Journal of Archaeological Science. - : Elsevier BV. - 0305-4403 .- 1095-9238. ; 105, s. 116-129
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the genetic composition of six Canis remains from western Iberia, directly radiocarbon dated to 7,903-7,570 years (cal BP). They were identified as dogs via their archaeological and depositional context, osteometry, and a high percentage of aquatic diet shared with humans. For comparison, genetic data were obtained from an additional 37 Iberian dog remains from the Neolithic to Late Antiquity, as well as two Palaeolithic and a Chalcolithic Canis identified as wolves. Previous data indicated that dog mtDNA haplogroup A (HgA) is prevalent in extant European dogs ( > 50%), in the Near East and Asia, but rare or absent ( < 10%) in European Canis older than 3,000 years (cal BP). We found a high frequency (83%) of dog HgA in Mesolithic Iberian dog remains. This is the first report of a high frequency of dog HgA in pre-Neolithic Europe. We show that, contrary to the current view, Canis with HgA did not necessarily arrive in Europe from East-Asia. This phylogeographical difference in HgA frequency demonstrates that genetic differentiation was high prior to, or as a consequence of, domestication which may be linked with pre-Neolithic local processes for Iberian wolf domestication. Our results emphasize that knowledge of both ancient wolves' and early dogs' genetic profiles from the European periphery should improve our understanding of the evolution of the European dog.
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| 29. |
- Pires, António Pazo, et al.
(författare)
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Assessment of Change in Psychoanalysis : Another Way of Using the Change After Psychotherapy Scales
- 2016
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Ingår i: Journal of the American Psychoanalytic Association. - : SAGE Publications. - 0003-0651 .- 1941-2460. ; 64:2, s. 285-305
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Tidskriftsartikel (refereegranskat)abstract
- A systematic method is presented whereby material from a full course of psychoanalytic treatment is analyzed to assess changes and identify patterns of change. Through an analysis of session notes, changes were assessed using the CHange After Psychotherapy scales (CHAP; Sandell 1987a), which evaluate changes in five rating variables (symptoms, adaptive capacity, insight, basic conflicts, and extratherapeutic factors). Change incidents were identified in nearly every session. Early in the analysis, relatively more change incidents related to insight were found than were found for the other types of change. By contrast, in the third year and part of the fourth year, relatively more change incidents related to basic conflicts and adaptive capacity were found. While changes related to symptoms occurred throughout the course of treatment, such changes were never more frequent than other types of change. A content analysis of the change incidents allowed a determination of when in the treatment the patient’s main conflicts (identified clinically) were overcome. A crossing of quantitative data with clinical and qualitative data allowed a better understanding of the patterns of change.
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| 30. |
- Santacruz-Perez, Carolina, et al.
(författare)
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A specific interdomain interaction preserves the structural and binding properties of the ModA protein from the phytopathogen Xanthomonas citri domain interaction and transport in ModA
- 2013
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Ingår i: Archives of Biochemistry and Biophysics. - : Elsevier BV. - 0003-9861 .- 1096-0384. ; 539:1, s. 20-30
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Tidskriftsartikel (refereegranskat)abstract
- The periplasmic-binding proteins in ATP-binding cassette systems (ABC Transporters) are responsible for the capture and delivery of ligands to their specific transporters, triggering a series of ATP-driven conformational changes that leads to the transport of the ligand. Structurally consisting of two lobes, the proteins change conformation after interaction with the ligand. The structure of the molybdate-binding protein (ModA) from Xanthomonas citri, bound to molybdate, was previously solved by our group and an interdomain interaction, mediated by a salt bridge between K127 and D59, apparently supports the binding properties and keeps the domains closed. To determinate the importance of this interaction, we built two ModA mutants, K127S and D59A, and analysed their functional and structural properties. Based on a set of spectroscopic experiments, crystallisation trials, structure determination and molecular dynamics (MD) simulations, we showed that the salt bridge is essential to maintain the structure and binding properties. Additionally, the MD simulations revealed that this mutant adopted a more compact structure that packed down the ligand-binding pocket. From the closed bound to open structure, the positioning of the helices forming the dipole and the salt bridge are essential to induce an intermediate state.
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| 31. |
- Santangelo, James S., et al.
(författare)
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Global urban environmental change drives adaptation in white clover
- 2022
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 375
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Tidskriftsartikel (refereegranskat)abstract
- Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural dines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.
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| 32. |
- Vilke, Juliano M., et al.
(författare)
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Looking beyond the obvious : The ecotoxicological impact of the leachate from fishing nets and cables in the marine mussel Mytilus galloprovincialis
- 2024
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Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 473
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Tidskriftsartikel (refereegranskat)abstract
- Once in the marine environment, fishing nets and cables undergo weathering, breaking down into micro and nano-size particles and leaching plastic additives, which negatively affect marine biota. This study aims to unravel the ecotoxicological impact of different concentrations of leachate obtained from abandoned or lost fishing nets and cables in the mussel Mytilus galloprovincialis under long-term exposure (28 days). Biochemical biomarkers linked to antioxidant defense system, xenobiotic biotransformation, oxidative damage, genotoxicity, and neurotoxicity were evaluated in different mussel tissues. The chemical nature of the fishing nets and cables and the chemical composition of the leachate were assessed and metals, plasticizers, UV stabilizers, flame retardants, antioxidants, dyes, flavoring agents, preservatives, intermediates and photo initiators were detected. The leachate severely affected the antioxidant and biotransformation systems in mussels' tissues. Following exposure to 1 mg·L-1 of leachate, mussels' defense system was enhanced to prevent oxidative damage. In contrast, in mussels exposed to 10 and 100 mg·L-1 of leachate, defenses failed to overcome pro-oxidant molecules, resulting in genotoxicity and oxidative damage. Principal component analysis (PCA) and Weight of Evidence (WOE) evaluation confirmed that mussels were significantly affected by the leachate being the hazard of the leachate concentrations of 10 mg·L-1 ranked as major, while 1 and 100 mg·L-1 was moderate. These results highlighted that the leachate from fishing nets and cables can be a threat to the heath of the mussel M. galloprovincialis.
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