Enhanced at puberty 1 (EAP1) is a new transcriptional regulator of the female neuroendocrine reproductive axis

The initiation of mammalian puberty and the maintenance of female reproductive cycles are events controlled by hypothalamic neurons that secrete the decapeptide gonadotropin-releasing hormone (GnRH). GnRH secretion is, in turn, controlled by changes in neuronal and glial inputs to GnRH-producing neurons. The hierarchical control of the process is unknown, but it requires coordinated regulation of these cell-cell interactions. Here we report the functional characterization of a gene (termed enhanced at puberty 1 [EAP1]) that appears to act as an upstream transcriptional regulator of neuronal networks controlling female reproductive function. EAP1 expression increased selectively at puberty in both the nonhuman primate and rodent hypothalamus. EAP1 encoded a nuclear protein expressed in neurons involved in the inhibitory and facilitatory control of reproduction. EAP1 transactivated genes required for reproductive function, such as GNRH1, and repressed inhibitory genes, such as preproenkephalin. It contained a RING finger domain of the C3HC4 subclass required for this dual transcriptional activity. Inhibition of EAP1 expression, targeted to the rodent hypothalamus via lentivirus-mediated delivery of EAP1 siRNAs, delayed puberty, disrupted estrous cyclicity, and resulted in ovarian abnormalities. These results suggest that EAP1 is a transcriptional regulator that, acting within the neuroendocrine brain, contributes to controlling female reproductive function.This work was supported by grants from the NIH, the National Institute of Child Health and Human Development/NIH (to S.R. Ojeda), the European Society for Paediatric Endocrinology (to H. Jung), the German Research Foundation (to S. Heger), and the European Commission (PIONEER to S. Heger)

Design, fabrication and characterization of piezoelectric cantilever MEMS for underwater application

This work shows a preliminary microfabrication route for a novel directional hydrophone based on a cross-shaped design of piezoelectric cantilevers. A thin layer of aluminum nitride (AlN) using Molybdenum (Mo) thin film as electrodes will be exploited as piezoelectric functional layer for the microfabrication of a cantilever-based ultrasonic micro electro mechanical system (MEMS) hydrophone. A parameterized simulation based on length of these cantilevers between 100 and 1000 μm allowed to set the first resonant mode between 20 kHz and 200 kHz, the desired underwater ultrasonic acoustic range. The microsystem was designed with cantilevers facing each other in a cross configuration in order to have novel MEMS hydrophone with an omnidirectional response. In order to investigate the first resonance frequency mode and displacement measurements, a Laser Doppler Vibrometer was used and good agreement between simulations and experimental results was achieved. Responsivity and directionality measurements of the piezoelectric MEMS cantilevers were performed in water. Maximum sensitivity up to −153 dB with omnidirectional directivity pattern was achieved by fabricated MEMS sensor

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

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

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

Efficient synthesis of kainic acid analogues

The present paper deals with an improved synthesis of two molecular hybrids of AMPA and KA, compounds CIP-A and CIP-B, and their transformation into CIOP-A and CIOP-B, the corresponding amido derivatives. Exploiting the continuous-flow technology, a significant improvement in the synthesis of the glutamate agonists CIP-A and CIP-B was accomplished, in terms of overall yield, time, and excess of ethyl chlorooximinoacetate. Moreover, we find out the HPLC conditions suitable to separate, at a preparative level, the three intermediates formed in the 1,3-dipolar cycloaddition step

Amortiguamiento de oscilaciones electromecánicas en central hidráulica

Se describen los estudios, simulaciones y ensayos realizados, para amortiguar oscilaciones electromecánicas, con la instalación de Estabilizadores de Potencia o “Power System Stabilizer” (PSS) en 4 unidades generadoras de 118 MW de una central hidráulica, conectada al sistema mediante una doble terna de 330 KV, en cuyo arribo existe una planta de aluminio con dos series de cubas de electrólisis, cada una de 160 MW. Dada la particularidad del sistema, se realizaron estudios de detalle del mismo. El estudio inició con la validación de una Base de Datos de todo el sistema, incluida la carga de la planta de aluminio. Se realizaron análisis modales junto con simulaciones temporales correspondientes a eventos determinados que excitan a los modos de oscilación electromecánica dominantes. Se hallaron valores de sintonía de los PSS, y se ponderó su influencia sobre los Reguladores Automáticos de Velocidad para no degradar su desempeño. Se realizaron ensayos durante la puesta en servicio de los PSS, cuyos resultados coincidieron con los estudios previos.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Amortiguamiento de oscilaciones electromecánicas en central hidráulica

Se describen los estudios, simulaciones y ensayos realizados, para amortiguar oscilaciones electromecánicas, con la instalación de Estabilizadores de Potencia o “Power System Stabilizer” (PSS) en 4 unidades generadoras de 118 MW de una central hidráulica, conectada al sistema mediante una doble terna de 330 KV, en cuyo arribo existe una planta de aluminio con dos series de cubas de electrólisis, cada una de 160 MW. Dada la particularidad del sistema, se realizaron estudios de detalle del mismo. El estudio inició con la validación de una Base de Datos de todo el sistema, incluida la carga de la planta de aluminio. Se realizaron análisis modales junto con simulaciones temporales correspondientes a eventos determinados que excitan a los modos de oscilación electromecánica dominantes. Se hallaron valores de sintonía de los PSS, y se ponderó su influencia sobre los Reguladores Automáticos de Velocidad para no degradar su desempeño. Se realizaron ensayos durante la puesta en servicio de los PSS, cuyos resultados coincidieron con los estudios previos.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Synthesis of L-tricholomic acid analogues and pharmacological characterization at ionotropic glutamate receptors

The synthesis of analogues of the natural compound ltricholomic acid and of its threo diastereoisomer was accomplished in order to explore their affinity for glutamate ionotropic receptors. In this study, fourteen new unnatural amino acids, characterized by a 3-hydroxy-~2 -isoxazoline or 3- hydroxy-~2 -pyrazoline-skeleton, were obtained exploiting, as key reaction, a 1,3-dipolar cycloaddition or an intramolecular cyclization