A simple modulation approach for interfacing three-level Neutral-Point-Clamped converters to the grid

Datos suplementarios: https://ars.els-cdn.com/content/image/1-s2.0-S0360544220309427-mmc1.mp4Multilevel converters are nowadays an enabling key in the integration of electric power into the grid as they introduce less distortion and, thus, they are more compliant with the grid standards, among other benefits. A well-known topology is the three-level Neutral-Point-Clamped whose control requires to deal with the capacitors voltage unbalance. This paper presents a modulation approach where the injection of a common component in the modulated voltage is studied in order to achieve such voltage balance. An optimization problem that, apart from the voltage balance, aims the lowest number of commutations and can be solved very efficiently with up to five computations of the cost function is formulated. The main advantages of the proposed modulation strategy are its simplicity and its flexibility, since it is also valid for unbalanced grid conditions and, with little added complexity, for low (and even zero) power factor conditions. Simulation results under unbalanced grid conditions are provided in order to show its validity under this scenario. The strategy is evaluated and compared with a space-vector-based approach in an experimental setup, yielding similar total harmonic current distortion, a 30% reduction in the number of commutations, and better voltage balance performance for lower power factor conditions.Ministerio de Economía y Competitividad DPI2016-75294-C2-1-RJunta de Andalucía (Consejería de Economía y Conocimiento), Programa Operativo FEDER Andalucía 2014-2020, US-1264655

Pseudo-optimal five-level DCC modulation based on machine learning

This paper presents a method for the control design of five-level DCC converters based on mixed-integer optimization and machine learning. The resulting controller is computationally simple and can be easily implemented on low-resource control hardware using simple nested “if-else” statements. The optimization problem is recalled from previous work by modifying the cost function to further enhance the dynamic performance. Additionally, and in contrast to previous works, the online implementation accomplished in this paper allows the system to cover a wider range of operating points. For this, the optimization problem is solved offline for several operating conditions, and the results are gathered into a dataset to train classification and regression trees (CARTs), which are later used online. Due to the generalization capability of the CARTs, a more flexible and less resource-intensive implementation is achieved which is capable of operating at points outside the ones considered in the training dataset. The resulting control strategy is compared in simulation and experiments with several alternative approaches found in the literature. This approach can be extended to other power converter topologies, allowing the implementation of optimized modulations

On the dynamic adaptation of language models based on dialogue information

We present an approach to adapt dynamically the language models (LMs) used by a speech recognizer that is part of a spoken dialogue system. We have developed a grammar generation strategy that automatically adapts the LMs using the semantic information that the user provides (represented as dialogue concepts), together with the information regarding the intentions of the speaker (inferred by the dialogue manager, and represented as dialogue goals). We carry out the adaptation as a linear interpolation between a background LM, and one or more of the LMs associated to the dialogue elements (concepts or goals) addressed by the user. The interpolation weights between those models are automatically estimated on each dialogue turn, using measures such as the posterior probabilities of concepts and goals, estimated as part of the inference procedure to determine the actions to be carried out. We propose two approaches to handle the LMs related to concepts and goals. Whereas in the first one we estimate a LM for each one of them, in the second one we apply several clustering strategies to group together those elements that share some common properties, and estimate a LM for each cluster. Our evaluation shows how the system can estimate a dynamic model adapted to each dialogue turn, which helps to improve the performance of the speech recognition (up to a 14.82% of relative improvement), which leads to an improvement in both the language understanding and the dialogue management tasks

Valoración de la prueba electrónica en Colombia: Su validez y aplicación en los años 2017-2019

Para el desarrollo del trabajo de investigación que tiene por objetivo general, indagar desde lo teórico, normativo y jurisprudencial sobre la prueba electrónica en Colombia, sus efectos jurídicos, validez y aplicación de acuerdo a procesos en los años 2017 a 2019, la investigación es de forma aplicada sociojurídica de tipo descriptiva, partiendo del análisis crítico que se realiza con base en vacíos normativos y la interpretación de normas que sirven de ayuda para evitar dudas y contradicciones en cuanto a su aplicación, y que pueden llegar a generar conflictos que tengan consecuencias negativas frente a la tutela judicial efectiva de los derechos reconocidos por la ley sustancial.Universidad Libre Seccional Pereira -- Facultad de Derecho, Ciencias Políticas y Sociales -- Derech

Basement membrane-rich Organoids with functional human blood vessels are permissive niches for human breast cancer metastasis

Metastasic breast cancer is the leading cause of death by malignancy in women worldwide. Tumor metastasis is a multistep process encompassing local invasion of cancer cells at primary tumor site, intravasation into the blood vessel, survival in systemic circulation, and extravasation across the endothelium to metastasize at a secondary site. However, only a small percentage of circulating cancer cells initiate metastatic colonies. This fact, together with the inaccessibility and structural complexity of target tissues has hampered the study of the later steps in cancer metastasis. In addition, most data are derived from in vivo models where critical steps such as intravasation/extravasation of human cancer cells are mediated by murine endothelial cells. Here, we developed a new mouse model to study the molecular and cellular mechanisms underlying late steps of the metastatic cascade. We have shown that a network of functional human blood vessels can be formed by co-implantation of human endothelial cells and mesenchymal cells, embedded within a reconstituted basement membrane-like matrix and inoculated subcutaneously into immunodeficient mice. The ability of circulating cancer cells to colonize these human vascularized organoids was next assessed in an orthotopic model of human breast cancer by bioluminescent imaging, molecular techniques and immunohistological analysis. We demonstrate that disseminated human breast cancer cells efficiently colonize organoids containing a functional microvessel network composed of human endothelial cells, connected to the mouse circulatory system. Human breast cancer cells could be clearly detected at different stages of the metastatic process: initial arrest in the human microvasculature, extravasation, and growth into avascular micrometastases. This new mouse model may help us to map the extravasation process with unprecedented detail, opening the way for the identification of relevant targets for therapeutic intervention

Surfactant Nebulization Therapy During NIPPV Ventilation in Surfactant-Deficient Newborn Piglets

Background In recent years, nasal intermittent positive pressure ventilation (NIPPV) has been growing in popularity as a form of noninvasive ventilation for respiratory support in the initial treatment of neonates with surfactant (SF) deficiency. The combination of this type of ventilation with noninvasive SF administration (by nebulization) is an attractive treatment option for respiratory distress syndrome (RDS)-associated pathophysiology of the neonatal lungs. In this study, we aimed to test the tolerability and efficacy of SF nebulization during NIPPV for the treatment of neonatal RDS. Methods Spontaneously-breathing newborn piglets (n = 6/group) with bronchoalveolar lavage (BAL)-induced RDS were assigned to receive during NIPPV (180 min): poractant alfa (400 mg/kg) via an investigational customized vibrating-membrane nebulizer (eFlow-Neos) or poractant alfa (200 mg/kg) as a bolus using the Insure method or no surfactant (controls). Measurement and results We assessed pulmonary, hemodynamic and cerebral effects and performed histological analysis of lung and brain tissue. After repeated BAL, newborn piglets developed severe RDS (FiO2: 1, pH  70 mmHg, PaO2< 70 mmHg, Cdyn < 0.5 ml/cmH2O/kg). In both SF-treated groups, we observed rapid improvement in pulmonary status and also similar hemodynamic, cerebral behavior, and lung and brain injury scores. Conclusion Our results in newborn piglets with severe BAL-induced RDS show the administration of nebulized poractant alfa using the eFlow-Neos nebulizer during NIPPV to be well tolerated and efficacious, suggesting that this noninvasive SF administration option should be explored further.Drs. Rey-Santano, Mielgo, and Gomez-Solaetxe's institutions received funding from Chiesi Farmaceutici and Carlos III Health Institute (PI18/00166) (co-funded by ERDF/ESF, "Investing in your future") and GIU19/026 (University of the Basque Country Research Group

Effectiveness of a physical therapeutic exercise programme for caregivers of dependent patients: a pragmatic randomised controlled trial from Spanish primary care

Producción CientíficaFemale family caregivers (FFCs) constitute one of the basic supports of socio-health care for dependence in developed countries. The care provided by FFCs may impact their physical and mental health, negatively affecting their quality of life. In order to alleviate the consequences of providing care on FFCs, the Spanish Public Health System has developed the family caregiver care programme (FCCP) to be applied in primary care (PC) centres. The effectiveness of this programme is limited. To date, the addition of a physical therapeutic exercise (PTE) programme to FCCP has not been evaluated. A randomised multicentre clinical trial was carried out in two PC centres of the Spanish Public Health System. In total, 68 FFCs were recruited. The experimental group (EG) performed the usual FCCP (4 sessions, 6 h) added to a PTE programme (36 sessions in 12 weeks) whereas the control group performed the usual FCCP performed in PC. The experimental treatment improved quality of life (d = 1.17 in physical component summary), subjective burden (d = 2.38), anxiety (d = 1.52), depression (d = 1.37) and health-related physical condition (d = 2.44 in endurance). Differences between the groups (p < 0.05) were clinically relevant in favour of the EG. The experimental treatment generates high levels of satisfaction.Ministerio de Economía, Industria y Competitividad - (Project MTM2017–86061-C2–1-P)Junta de Castilla y León y Fondo Europeo de Desarrollo Regional (FEDER) - (Projects VA005P17 y VA002G18

Manual de Usuario "Visor SIG"

Fil: Cuesta Llames, Jorge. SADIM: Sociedad Asturiana de Diversificación Minera; España.Fil: Ferpozzi, Federico Javier. Servicio Geológico Minero Argentino. Instituto de Geología y Recursos Minerales. Área de Sensores Remotos y SIG; Argentina.Fil: Pedreira Júnco, José Ángel. SADIM: Sociedad Asturiana de Diversificación Minera; España.Fil: Candaosa, Norberto Gabriel. Servicio Geológico Minero Argentino. Instituto de Geología y Recursos Minerales. Área de Sensores Remotos y SIG; Argentina

Development and validation of a specific questionnaire to assess health-related quality of life in patients with home enteral nutrition: NutriQoL® development

Introduction: Home enteral nutrition (HEN) is indicated in patients with a functional gastrointestinal tract but who are unable to meet their nutritional requirements with normally consumed foodstuffs. HEN allows patients to remain in their social and family environment, thus reducing complications and costs associated with hospital admission, while increasing health-related quality of life (HRQoL). HRQoL in patients with HEN is mainly evaluated by generic instruments, which are not sensitive enough to identify certain specific patient-related outcomes of HEN. Objective: To develop a specific instrument to measure HRQoL in patients receiving HEN whose results allow interpretation regardless of the underlying disease and nutritional support administration route: the NutriQoL® questionnaire. Materials and methods: The development of the NutriQoL entailed a literature review, focus groups with experts, semistructured interviews with patients, an assessment of face validity and feasibility, and Rasch analysis conducted on data from a sample of 141 patients and 24 caregivers. Results: Of the 52 items initially proposed on the basis of the literature review, expert focus group, and semi-structured interviews with patients and caregivers, 17 items were finally selected through the development process to make up the final version of the NutriQoL, as well as a visual analog scale for global HRQoL scoring. The selected items were evaluated as adequate for frequency, importance, and clarity. Furthermore, they have been shown to be independent of the underlying condition and HEN administration route. Conclusion: A new instrument for measuring the HRQoL of patients with HEN in Spain has been developed, whose results are independent of the underlying condition and administration route. The next step will be the validation of the questionnaire to ensure that the instrument is valid, reliable, and sensitive to health status changes in patients, to be used periodically in usual clinical practice.The abstract of this paper was presented at the International Society for Pharmacoeconomics and Outcomes Research 17th Annual European Congress (Amsterdam, the Netherlands) on November 2014 as a poster with interim findings. The poster’s abstract was published in “Value in Health” Vol 17, Issue 7, A518 (http://www.valueinhealthjournal.com/article/S1098-3015(14)03541-4/pdf) and A575 (http://www.sciencedirect.com/science/article/pii/S1098301514038650). Nestlé Health Science sponsored the stud