Hydropower plant models: water supply system, turbine and governor : Model validation: on site tests and grid fault simulation

Several tests were conducted at Futaleufú hydropower plant to improve plant related models because studies carried out in the past did not predict the power plant behaviour during grid faults. New models were used to reproduce Futaleufú power plant behaviour during a grid fault happened on December 14, 2006.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Hydropower plant models: water supply system, turbine and governor : Model validation: on site tests and grid fault simulation

Several tests were conducted at Futaleufú hydropower plant to improve plant related models because studies carried out in the past did not predict the power plant behaviour during grid faults. New models were used to reproduce Futaleufú power plant behaviour during a grid fault happened on December 14, 2006.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Pattern matching in high energy physics by using neural network and genetic algorithm

In this paper two different approaches to provide information from events by high energy physics experiments are shown. Usually the representations produced in such experiments are spot-composed and the classical algorithms to be needed for data analysis are time consuming. For this reason the possibility to speed up pattern recognition tasks by soft computing approach with parallel algorithms has been investigated. The first scheme shown in the following is a two-layer neural network with forward connections, the second one consists of an evolutionary algorithm with elitistic strategy and mutation and cross-over adaptive probability. Test results of these approaches have been carried out analysing a set of images produced by an optical ring imaging Cherenkov (RICH) detector at CERN

Inclusion of motor evoked abnormalities in amyotrophic lateral sclerosis: a diagnostic algorithm to early classify lower motor neuron phenotypes

no abstrac

Wearable piezoelectric mass sensor based on pH sensitive hydrogels for sweat pH monitoring

Colorimetric and electrochemical (bio)sensors are commonly employed in wearable platforms for sweat monitoring; nevertheless, they suffer from low stability of the sensitive element. In contrast, mass-(bio)sensors are commonly used for analyte detection at laboratory level only, due to their rigidity. To overcome these limitations, a flexible mass-(bio)sensor for sweat pH sensing is proposed. The device exploits the flexibility of piezoelectric AlN membranes fabricated on a polyimide substrate combined to the sensitive properties of a pH responsive hydrogel based on PEG-DA/CEA molecules. A resonant frequency shift is recorded due to the hydrogel swelling/shrinking at several pH. Our device shows a responsivity of about 12 kHz/pH unit when measured in artificial sweat formulation in the pH range 3-8. To the best of our knowledge, this is the first time that hydrogel mass variations are sensed by a flexible resonator, fostering the development of a new class of compliant and wearable devices

Can the onset of orbital cancer be the result of a prosthetic eye?

Lexenteratio orbitae è un intervento deturpante che si pratica in caso di infezioni orbitarie non responsive a terapia medica e in caso di tumori benigni ricorrenti e tumori maligni che insorgono dalle palpebre (carcinoma basocellulare, carcinoma squamocellulare, melanoma maligno della congiuntiva), dalle ghiandole lacrimali (carcinoma adenoideo cistico) o dalle strutture circostanti. In casi estremamente rari luso di protesi oculari dopo lenucleazione può causare linsorgenza di tumori orbitari. In questo articolo riportiamo il caso di un uomo di 54 anni che è stato sottoposto ad enucleazione dellocchio sinistro in seguito a ricorrenti distacchi di retina e che ha sviluppato, solo 30 anni dopo, un carcinoma epidermoidale infiltrante a rapida crescita. Abbiamo esaminato gli articoli in letteratura per valutare la rarità di tale occorrenza, i tempi dinsorgenza in seguito allenucleazione, i trattamenti e i risultati. Il nostro caso illustra il trattamento della patologia ed enfatizza la necessità di un attento esame della cavità orbitaria e della protesi oculare per identificare anche le irregolarità e i primi danni sulla superficie orbitaria anche nei casi in cui lexenteratio orbitae è stata eseguita per patologie benigne. Il nostro caso dimostra che il follow-up a lungo termine è fondamentale perché il tumore può insorgere a lunga distanza dopo lenucleazione

Hydraulic transients in hydropower plant : Impact on power system dynamic stability

Futaleufú hydropower plant has 4 Francis turbines rated 118 MW and it is connected to the power system by 2x330 kV lines. Studies carried out in the past did not predict the instable operation of Futaleufú after a 330 kV line fault, when some Futaleufú turbines are automatically disconnected as a consequence of the faulted line tripping. Load rejection caused by disconnected turbines generate large transients in the remaining turbines due to hydraulic coupling through the common conduits. Then, to improve related models and, therefore, to improve studies results of such a line fault it was necessary to make several tests in Futaleufú power plant. Finally, these models were used to conduct studies to design a new automatism, like the gate partial closing of the remaining turbines, to obtain a dynamically stable operation of Futaleufú after the disconnection by fault of a line of 330 kilovolts.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctrico

Motor-evoked potentials in amyotrophic lateral sclerosis: potential implications in detecting subclinical UMN involvement in lower motor neuron phenotype

Background: In amyotrophic lateral sclerosis (ALS), the involvement of lower motor neuron is well defined by electromyography, whereas a reliable marker of upper motor neuron (UMN) damage still lacks. Aim of the study was to estimate the role of transcranial magnetic stimulation (TMS)-induced motor-evoked potentials (MEPs) as marker of subclinical UMN involvement. Methods: Clinical evidence of UMN damage was prospectively compared to MEPs in 176 ALS patients diagnosed between 2011 and 2014, and classified according to existing diagnostic criteria. Finally, we evaluated the appearance of clinical UMN signs and the level of diagnostic certainty in ALS after 1 year of follow-up. Results: At presentation, abnormal MEPs were found in 80% of patients with clinical evidence of UMN damage and in 72% of patients without clinical involvement of UMN. Among these latter, 61% showed appearance of UMN clinical signs after 1 year. Approximately 70% of patients with clinical lower motor neuron (LMN) phenotype showed MEP abnormalities, while they were considered not classifiable ALS according to Airlie house or Awaji criteria. Furthermore, abnormal MEPs in absence of clinical UMN signs at baseline were found in 80% of spinal ALS that after 1-year developed UMN signs at limbs, compared to 50% of bulbar ALS. Conclusions: TMS is a reliable marker of subclinical UMN damage particularly among LMN phenotype and ensure an early ALS diagnosis in ~ 70% of such cases

Operación inestable de Central Hidroeléctrica Futaleufú por transitorios hidráulicos : Descripción y solución del problema

La central hidroeléctrica Futaleufú pertenece al Sistema Interconectado Patagónico (SIP) y se vincula con la ET Puerto Madryn mediante 2 líneas de 330 kV. En el año 2006 el SIP se interconectó con el Sistema Argentino de Interconexión (SADI) mediante 1 línea de 500 kV entre ET Puerto Madryn (SIP) y ET Choele Choel (SADI). Con el SIP aislado del SADI y operando Futaleufú con 4 unidades, ante el disparo por falla de una línea de 330 kV la operación post-falla de Futaleufú resulta estable si en dicha central se realiza la Desconexión Automática de Generación (DAG) de una unidad, mientras que con el SIP y el SADI interconectados los estudios realizados indicaban la necesidad de realizar DAG de 2 unidades. Con la interconexión SIP-SADI en servicio, una falla ocurrida el 14-03-2006 hizo actuar automatismos que provocaron la DAG de 2 unidades de Futaleufú y la desconexión de una línea de 330 kV. En tales condiciones, en servicio 1 línea de 330 kV y 2 unidades de Futaleufú, se produjo un transitorio inestable que finalizó con la desconexión de las 2 restantes unidades de Futaleufú. Este episodio no pudo ser reproducido por simulaciones con los modelos disponibles. En los registros del incidente del 14-03-2006 se observa un aumento sustancial de las potencias eléctricas de las 2 unidades de Futaleufú que quedaron en servicio. Este comportamiento solamente podía ser justificado si se tenía en cuenta el transitorio en el sistema hidráulico producido por la DAG de otras turbinas de la central. Por tal motivo se realizaron ensayos en Futaleufú que permitieron modelar el sistema hidráulico y su impacto sobre las potencias de las turbinas en servicio. Estos ensayos también permitieron verificar y agregar mayor detalle a los modelos de Futaleufú disponibles a esa fecha. Fueron ensayados las turbinas y sus controles de velocidad (governor), los sistemas de excitación y sus controles (AVR). También fueron ensayados los estabilizadores de potencia (PSS) para verificar los reajustes realizados en los mismos. Con los nuevos modelos se reprodujo por simulación el incidente del 14-03-2006. Estudios realizados con estos modelos demostraron la efectividad de una Reducción Automática de Generación (RAG) de las 2 turbinas de Futaleufú en servicio luego del disparo de una línea de 330 kV. Finalmente, se presentan registros de la desconexión por falla de una línea de 330 kV ocurrida el 18-5-2008 donde se observa la actuación de la RAG en las turbinas de Futaleufú y su consecuente comportamiento estable en el transitorio post-falla.Facultad de Ingenierí

Smart materials based on DNA aptamers: Taking aptasensing to the next level

"Smart" materials are an emerging category of multifunctional materials with physical or chemical properties that can be controllably altered in response to an external stimulus. By combining the standard properties of the advanced material with the unique ability to recognize and adapt in response to a change in their environment, these materials are finding applications in areas such as sensing and drug delivery. While the majority of these materials are responsive to physical or chemical changes, a particularly exciting area of research seeks to develop smart materials that are sensitive to specific molecular or biomolecular stimuli. These systems require the integration of a molecular recognition probe specific to the target molecule of interest. The ease of synthesis and labeling, low cost, and stability of DNA aptamers make them uniquely suited to effectively serve as molecular recognition probes in novel smart material systems. This review will highlight current work in the area of aptamer-based smart materials and prospects for their future applications