Complex-Variable Sliding-Mode Control of Instantaneous Complex Energy and Power for Grid-Tied Inverter

A complex-variable sliding-mode control (SMC) algorithm is proposed to govern inverters interfacing renewable energy sources (RESs) with the electrical grid. It is conceived to control the instantaneous energy stored in the passive components of the system and its rate of change, as well as the instantaneous reactive energy and power exchanged with the grid. The stability of the resulting closed-loop system is analyzed, and tuning of the designed SMC algorithm is also tackled. In addition, the design and tuning of a nonlinear observer estimating the renewable power supplied to the DC link are addressed. The overall control scheme obtained by combining the proposed complex-variable SMC algorithm with such observer is assessed in simulation, demonstrating its outstanding tracking performance and high robustness in presence of large parameter variations.Co-financed by the MICIN/AEI/10.13039/501100011033 (project code PID2020-115484RA-I00), by the Basque Government under research grant IT1644-22, by the Universidad Nacional del Sur (UNS), and by the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)

Network Rewiring of Homologous Recombination Enzymes during Mitotic Proliferation and Meiosis.

Homologous recombination (HR) is essential for high-fidelity DNA repair during mitotic proliferation and meiosis. Yet, context-specific modifications must tailor the recombination machinery to avoid (mitosis) or enforce (meiosis) the formation of reciprocal exchanges-crossovers-between recombining chromosomes. To obtain molecular insight into how crossover control is achieved, we affinity purified 7 DNA-processing enzymes that channel HR intermediates into crossovers or noncrossovers from vegetative cells or cells undergoing meiosis. Using mass spectrometry, we provide a global characterization of their composition and reveal mitosis- and meiosis-specific modules in the interaction networks. Functional analyses of meiosis-specific interactors of MutLγ-Exo1 identified Rtk1, Caf120, and Chd1 as regulators of crossing-over. Chd1, which transiently associates with Exo1 at the prophase-to-metaphase I transition, enables the formation of MutLγ-dependent crossovers through its conserved ability to bind and displace nucleosomes. Thus, rewiring of the HR network, coupled to chromatin remodeling, promotes context-specific control of the recombination outcome

Análisis de los servicios de test del VIH de cinco centros comunitarios españoles para la mejora de nuevas estrategias de promoción del diagnóstico precoz

Background: In recent years, the number of people tested for HIV has experienced a significant increase. The purpose of this study is to analyze data obtained in Spain in the HIV testing services of five Community Centres members of Agrupación Prueba de VIHda throughout 2014 and 2015,to determine its effectiveness and to characterize the subpopulation with a HIV reactive result. Study design and methods: agrupación Prueba de VIHda performed free, anonymous and confidential HIV tests according to the Consolidated guidelines on HIV testing services of WHO (2015). Data were collected using the questionnaire of the COBATEST network, developed by the COBATEST Project, and its significance was determined statistically. Results: 3061 HIV tests were performed during 2014 and 2015, with a prevalence of reactive results of 2.5%. Heterosexual and bisexual men got tested at older ages than homosexual men and women. Non-Spanish origin seems to be a risk factor for HIV infection within the sample. Bisexual men showed as high prevalence of reactive test as homosexual men, as well as they reported less previous HIV tests. Finally, index testing performed by HIV positive peer educators to the sexual partners of newly diagnosed patients showed higher prevalence than that of the classical Voluntary Counselling and Testing approach outreach most at risk populations. Conclusion:The analysis of the data shows higher prevalence of reactive results in people of non-Spanish origin compared to that of the Spanish subgroup, the former still facing barriers to access the public health system in Spain. It also demonstrates the need of new and adapted approaches for promoting early diagnosis specifically in bisexual men. Index testing by peer HIV positive educators is a highly effective method for testing people at high risk of acquiring HIV infection.Antecedentes: En los últimos años, el número de personas sometidas a pruebas frente al VIH ha experimentado un aumento significativo. El propósito de este estudio es analizar los datos de prevalencia de la infección por VIH obtenidos por cinco centros comunitarios en España pertenecientes a la Agrupación Prueba de VIHda entre 2014 y 2015, determinar su efectividad y caracterizar la subpoblación con un resultado preliminar reactivo. Diseño experimental y métodos: La Agrupación Prueba de VIHda realizó pruebas de VIH gratuitas, anónimas y confidenciales de acuerdo con las directrices consolidadas por la OMS (2015). Los datos fueron recogidos mediante el cuestionario desarrollado por el Proyecto COBATEST y su significación se determinó estadísticamente. Resultados: Durante 2014 y 2015 se realizaron un total de 3061 pruebas frente al VIH, obteniendo una prevalencia de resultados preliminares positivos del 2,5%. Los hombres heterosexuales y bisexuales se realizaron la prueba a edades más avanzadas que los hombres homosexuales y las mujeres. Las personas de origen no español parecieron mostrar un mayor riesgo de infección frente al VIH. Hombres bisexuales mostraron una prevalencia elevada similar a la de hombres homosexuales, así como declararon menos pruebas anteriores frente al VIH. Finalmente, las pruebas realizadas a través de indextesting por los educadores pares de VIH a parejas sexuales de pacientes recién diagnosticados mostraron una prevalencia superior a la obtenida por el modelo tradicional de counselling y testado voluntario ofrecido desde los centros comunitarios a poblaciones de mayor riesgo. Conclusión: El análisis de los datos muestra mayores prevalencias de resultados preliminares reactivos en personas de origen no español comparadas con aquellas del subgrupo de personas españolas, el primero de ellos todavía enfrentando barreras de acceso al sistema sanitario público en España, El análisis también demuestra la necesidad de nuevos enfoques adaptados para promover el diagnóstico precoz especialmente entre hombres bisexuales. Las pruebas realizadas a través de indextesting por educadores pares VIH positivos es un método muy eficaz para el testado de las personas con alto riesgo de contraer la infección por VIH

The p38/MK2/Hsp25 Pathway Is Required for BMP-2-Induced Cell Migration

Background: Bone morphogenetic proteins (BMPs) have been shown to participate in the patterning and specification of several tissues and organs during development and to regulate cell growth, differentiation and migration in different cell types. BMP-mediated cell migration requires activation of the small GTPase Cdc42 and LIMK1 activities. In our earlier report we showed that activation of LIMK1 also requires the activation of PAKs through Cdc42 and PI3K. However, the requirement of additional signaling is not clearly known. Methodology/Principal Findings: Activation of p38 MAPK has been shown to be relevant for a number of BMP-2¿s physiological effects. We report here that BMP-2 regulation of cell migration and actin cytoskeleton remodelling are dependent on p38 activity. BMP-2 treatment of mesenchymal cells results in activation of the p38/MK2/Hsp25 signaling pathway downstream from the BMP receptors. Moreover, chemical inhibition of p38 signaling or genetic ablation of either p38¿ or MK2 blocks the ability to activate the downstream effectors of the pathway and abolishes BMP-2-induction of cell migration. These signaling effects on p38/MK2/Hsp25 do not require the activity of either Cdc42 or PAK, whereas p38/MK2 activities do not significantly modify the BMP-2-dependent activation of LIMK1, measured by either kinase activity or with an antibody raised against phospho-threonine 508 at its activation loop. Finally, phosphorylated Hsp25 colocalizes with the BMP receptor complexes in lamellipodia and overexpression of a phosphorylation mutant form of Hsp25 is able to abolish the migration of cells in response to BMP-2. Conclusions: These results indicate that Cdc42/PAK/LIMK1 and p38/MK2/Hsp25 pathways, acting in parallel and modulating specific actin regulatory proteins, play a critical role in integrating responses during BMP-induced actin reorganization and cell migration

Relating the Chondrocyte Gene Network to Growth Plate Morphology: From Genes to Phenotype

During endochondral ossification, chondrocyte growth and differentiation is controlled by many local signalling pathways. Due to crosstalks and feedback mechanisms, these interwoven pathways display a network like structure. In this study, a large-scale literature based logical model of the growth plate network was developed. The network is able to capture the different states (resting, proliferating and hypertrophic) that chondrocytes go through as they progress within the growth plate. In a first corroboration step, the effect of mutations in various signalling pathways of the growth plate network was investigated

Interoperability and Mobility for Vital Signs Monitoring System

This presentation at the Med-e-tel 2005 Conference in Luxembourg on April 6th, 2005.Effects and Benefits of eHealth: Lessons Learned in Four Continents: Presented is the development of a mobile vital signs monitoring system based on vendor-independent open communication standards, such as Bluetooth wireless technology and the CEN ISO / IEEE 11073, allowing plug-and-play interoperability and therefore a rapid and easy assembly of wearable devices.Visual Interaction and Communication Technologies Center, Spai

Sliding-Mode Control for DFIG Rotor- and Grid-Side Converters Under Unbalanced and Harmonically Distorted Grid Voltage

International audienceRegarding doubly fed induction generator (DFIG) operation, unbalanced and harmonically distorted grid voltage conditions have been treated as two separate control problems. This paper reports a solution for the rotor- and grid-side power converters, which allows one to keep the DFIG successfully in operation under both grid voltage conditions. The proposed solution is based on sliding-mode control (SMC). The rotor-side converter is commanded so that the electromagnetic torque and the stator reactive power remain free of fluctuations that arise during grid voltage disturbances. Meanwhile, the grid-side converter ensures both constant DC-link voltage and steady active power output from the overall system. The developed algorithms turn out being robust against parameter variations and of fast dynamic response. In addition, none of the converters need either voltage or current positive and negative sequences extraction. The simulation results presented demonstrate the appropriateness of SMC to face such disturbed scenarios. Finally, the stability proof of both converters' control algorithms is provided in the appendices

Stratigraphy of the Hameima and lower Fahdene Formations in the Tadjerouine area (Northern Tunisia)

In the Tadjerouine area of north-western central Tunisia, the Albian transgression is characterized by deposition of alternating marls, limestones and sandstones (Hameima Fm) that overly massive platform carbonate rocks (Serdj Fm). The continuing transgression results in deposition of a thick series of marls and shales with subordinate carbonate beds (Fahdene Fm). A detailed study of the Hameima Fm, previously ascribed to the Late Aptian, shows that this formation can be subdivided into three members, all of earliest Albian age (Leymeriella tardefurcata Zone). The top of the Hameima Fm is slightly diachronous in the study area. A similar study of the Lower Shales of the Fahdene Fm demonstrates that they belong to the L. tardefurcata Zone and to the lower part of the Douvilleiceras mammillatum superzone. The overlying Allam limestones, formerly considered Middle Albian in age, are mainly of late Early Albian age (upper part of the D. mammillatum Superzone and Lyelliceras pseudolyelli Zone), although an extension into the lower Middle Albian cannot be ruled out. The Allam limestones are abruptly overlain by a diachronous series of Late Albian shales (Middle Shales of the Fahdene Fm), thus evidencing a stratigraphic hiatus of most of the Middle Albian and part of the early Late Albian. Our new data will lead to revision of the range of some Aptian/Albian orbitolinids and Albian planktic foraminifera

Control de un inversor auto sincronizado que inyecta potencia instantánea compleja en la red eléctrica

En este trabajo se propone un controlador no lineal para un inversor trifásico que inyecta energía, proveniente de una fuente renovable, en la red eléctrica. El controlador propuestoutiliza un observador para estimar la tensión de red, y por esta razón, no es necesario medir la misma para obtener la sincronización. La estrategia considera un controlador donde se define el seguimiento de referencias arbitrarias de la tensión en el bus de continua y de la potencia reactiva instantánea. La potencia a ser inyectada se supone proveniente de una fuente de potencia constante que alimenta al inversor. El controlador emplea  linealización por realimentación combinada con una ley de modo deslizante, donde la superficie de deslizamiento es una función no lineal de las variables que describen al sistema: la energía en el capacitor del bus de continua y la potencia instantánea compleja inyectada a la red. La potencia de entrada es estimada y el valor de su estima es incorporado en la ley de control como una compensación feedforward. De esta manera, nel esquema propuesto presenta un n´umero reducido de sensores, donde es necesario medir la corriente que se inyecta en la red y la tensión en el capacitor del bus de continua. El desempeño del sistema, cuando se utiliza el controlador propuesto, se valida mediante simulaciones.Fil: Solsona, Jorge Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Gómez Jorge, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Busada, Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Tapia Otaegui, G.. Universidad del País Vasco; EspañaFil: Susperregui, A.. Universidad del País Vasco; EspañaFil: Martínez, M. I.. Universidad del País Vasco; EspañaXIX Reunión de Trabajo en Procesamiento de la Información y ControlArgentinaUniversidad Nacional de San Juan. Instituto de Automátic