2,882 research outputs found
Col·laboració 2.0: El futur de la divulgació científica
La divulgació científica ha d’afrontar un nou escenari on l’escassetat d’informació ha estat substituïda per l’abundància d’informació, que a més comença a ser generalment gratuïta i produïda per aficionats i, en alguns casos, amb la mateixa o superior qualitat que la professional. Sembla imposar-se, en conseqüència, una col·laboració entre l’àmbit professional i l’aficionat, àmbits separats per una línia divisòria que ja s’ha desdibuixat
Diseño de front-end de receptor óptimo de alta ganancia y eficiencia de potencia en 0.13 μm de tecnología CMOS de RF para aplicaciones de 10GBPS
Este artículo presenta dos versiones de una RF frontend completa para un receptor óptico de 10Gbps. El RF frontend consiste de un amplificador de transimpedancia y amplificador limitador. Se proponen dos versiones de amplificadores TIA. La primera topología tiene una ganancia de transimpedancia de 54 dB, ancho de banda de 11.5 GHz y una salida de densidad de ruido de corriente de solamente 6.8 pA/√ Hz. La segunda topología esta compuesta de una cascada de dos invertores. Esta topología tiene una ganancia de 48 dB de transimpedancia. El amplificador limitador para ambos receptores ópticos es un amplificador de cinco etapas cherry-hooper con inductores activos optimizados para potencia baja. El amplificador principal tiene 38 dB de ganancia, 9.8 GHz de ancho de banda, 69 mW de consumo de potencia y solamente 0.171 mm2 de área muerta. Esta completa fachada de RF está integrada y tiene 10GHz de ancho de banda. Los circuitos fueron diseñados en 0.13 μm de tecnología CMOS de RF
Theoretical study of the high pressure effect in the crystalline structure and properties of the indium selenide
Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2018/2019The aim of this project is the theoretical study, using Crystal software, of the R3m
(α) and P61 (γ) In2Se3 phases stability and properties under pressure
Do marketing margins change with food scares?: Examining the effects of food recalls and disease outbreaks in the us red meat industry
This paper examines the impact of food scares on marketing margins in the US beef and pork industry. We analyze how market stresses induced by different food recalls and disease outbreaks affect price margins and the extent of price transmission at the slaughter-to-wholesale and wholesale-to-retail levels. We use monthly data for the period 1986–2008. The results indicate that marketing margins are differentially affected by Food Safety and Inspection Service (FSIS) recalls and bovine spongiform encephalopathy (BSE) outbreaks at different levels of the beef and pork marketing chain, although the effects are generally quite modest. Only BSE discoveries in the United States considerably affect marketing margins in the beef industry, specifically at the wholesale-to-retail level, as well as the extent of price transmission at the bottom of the beef and pork marketing channel. We also find that food safety incidents have minor cross-industry and cross-country effects on marketing margins.marketing margins, price transmission, food recalls, BSE outbreaks, red meat industry,
Dynamical signatures of topological order in the driven-dissipative Kitaev chain
We investigate the effects of dissipation and driving on topological order in
superconducting nanowires. Rather than studying the non-equilibrium steady
state, we propose a method to classify and detect dynamical signatures of
topological order in open quantum systems. Bulk winding numbers for the
Lindblad generator of the dissipative Kitaev chain are
found to be linked to the presence of Majorana edge master modes -- localized
eigenmodes of . Despite decaying in time, these modes
provide dynamical fingerprints of the topological phases of the closed system,
which are now separated by intermediate regions where winding numbers are
ill-defined and the bulk-boundary correspondence breaks down. Combining these
techniques with the Floquet formalism reveals higher winding numbers and
different types of edge modes under periodic driving. Finally, we link the
presence of edge modes to a steady state current.Comment: Submission to SciPost. 29 pages, 8 figure
Mecanismos alternativos de solución de controversias en el contrato estatal la amigable composición
Con este documento se pretende adentrarse mucho más en el estudio de los mecanismos alternativos de solución de controversias que puedan surgir dentro del desarrollo del contrato estatal y en especial el mecanismo denominado como la Amigable Composición de muy poca utilización entre las partes en conflicto pese a tener muchas ventajas en lo que tiene que ver con el procedimiento establecido para llevarla a cabo, efectos legales luego de su realización y la posibilidad de intervención de un tercero imparcial.
Se entrara a manejar el tema desde las definiciones de cada uno de los mecanismos alternativos de solución de controversias consagrado para dirimir los conflictos que puedan surgir con ocasión de la celebración de un contrato estatal, hasta llegar a la comparación de cada uno de estos métodos con la Amigable Composición, estableciendo similitudes y diferencias para que el lector tenga los criterios suficientes para emitir una opinión en lo que tiene que ver con la mayor idoneidad de uno u otro mecanismo alternativo de solución de controversias
Violencia sexual y de género y los mecanismos de protección jurídica en la legislación laboral chilena
The following article is a review of Chilean labor law that searches for legal answers to sexual and gender violence suffered by people in the workplace context. Firstly, the concepts of sexual and gender violence are analyzed. Then, the mechanisms that the national labor law gives to deal with the violations are analyzed, exposing that they have a repressive rather than a dissuasive dimension. With that in mind, the mandatory contents of the Order, Hygiene and Safety Internal Regulation, dismissal by severe grounds, indirect dismissal, the labor protection procedure and the complaints before the Labor Inspection are reviewed. Finally, the effectiveness of those mechanisms in preventing the occurrence of sexual or gender violence, in sanctioning them and in protecting the rights of the person who suffered such violations will be reviewed.El presente artículo es una revisión de la legislación laboral chilena en búsqueda de las respuestas legislativas que se otorgan a las situaciones de violencia sexual y de género sufridas por las personas en el contexto de la empresa. Para ello, se analizan en primer momento los conceptos de violencia sexual y de género, haciendo un repaso de aquello que implica cada uno de los mismos. Posteriormente, se analizan los mecanismos que la legislación nacional laboral otorga para hacer frente a tales vulneraciones, dando cuenta de que los mismos tienen una dimensión represiva y no disuasiva. Así las cosas, se revisa la aplicación de las obligaciones de contenido del Reglamento interno de orden, higiene y seguridad; el despido por causal grave; el despido indirecto; el procedimiento de tutela laboral; y la denuncia ante la inspección del trabajo. Finalmente, se revisa su utilidad para evitar la ocurrencia de situaciones de violencia sexual o de género, de sancionarlas y, en definitiva, el resguardo de los derechos de la persona que sufra tales vulneraciones
Technological approaches to improve the engine efficiency and to reduce pollutant emissions of automotive diesel engines.
The research work was mainly focused on the technological approach to improve engine efficiency and reduce pollutant emissions applicable to diesel engines which are very often incompatible were assessed through a set of full- scale tests on a real diesel engine in order to satisfy the new emissions limits.
(1) The first strategy evaluated in this work to improve the engine efficiency was the reduction of the mechanical losses: through the incorporation of nanomaterials in the lubricant formulation. The effect of the lubricant oil additivated with MoS2 nanopowders was assessed through a set of full - scale tests on a real diesel engine – several engine points and cooling water temperatures were investigated for both a reference oil and a MoS2-additivated one.
(2) Other strategy to reduce pollutant emissions included in this PhD thesis was the effects of using a 30% by volume blend of a renewable fuel, called Farnesane, and fossil diesel in a small Euro 5 displacement passenger car diesel engine.
(3) And finally, the CeO2/BaO/Pt system was selected in order to perform an NO2-assisted soot oxidation, as a aftertreatment strategy to reduce pollutant emissions. The aim of such catalytic system is to couple the catalytic functionality for soot abatement during DPF regeneration, namely CeO2, and an embedded lean NOx trap (LNT) functionality given by BaO, for NOx storage, whose oxidation over Pt to form adsorbed nitrates is facilitated by the presence of CeO2 itself
The Role of Branched-Chain Amino Acids in the Aquaculture of Red Drum, Sciaenops ocellatus L. ̶ Defining Dietary Requirements and Elucidating Antagonistic Effects
Five separate feeding trials were conducted to investigate branched-chain amino acid (BCAA) nutrition of red drum (Sciaenops ocellatus). First, the minimum dietary requirements of the BCAAs (leucine [Leu], isoleucine [Ile] and valine [Val]) were determined for juvenile red drum. Three independent 49-d feeding trials were conducted. Experimental diets were prepared by supplementing a basal diet containing 37 g/kg crude protein (CP) from red drum muscle (RDM) and crystalline amino acids (AAs) with incremental levels of Leu (9.0, 13.0, 17.0, 21.0, 25.0 and 29.0 g/kg of dry diet), Ile (5.0, 8.0, 11.0, 14.0, 17.0 and 20.0 g/kg of dry diet) and Val (6.8, 8.0, 9.2, 10.4, 11.6, 12.8 and 14.0 g/kg of dry diet). Fish in triplicate 30-L glass aquaria were fed each experimental diet to apparent satiation twice daily, after which growth performance parameters were measured. Incremental levels of dietary Leu, Ile and Val significantly affected weight gain, feed efficiency and protein retention. Analyses of the weight gain data using a broken-line regression model estimated the minimum Leu, Ile and Val requirements for maximum weight gain of juvenile red drum to be 15.7 ± 1.7 g/kg (± 95% confidence interval), 11.1 ± 2.3 g/kg and 12.4 ± 0.6 g/kg of dry diet, respectively.
Secondly, the effects of high dietary levels of BCAAs on growth performance and AA utilization of juvenile red drum were determined. A semi-purified control diet (430 g/kg CP) was prepared by combining lyophilized RDM and crystalline AAs, while keeping the levels of Leu, Ile and Val at the minimum dietary requirement for red drum. Six experimental diets were prepared by supplementing the control diet with (1) an excess of Leu (62.0 g/kg of dry diet), (2) an excess of Ile (44.0 g/kg of dry diet), (3) an excess of Val (50.0 g/kg of dry diet), (4) an excess of Leu and Ile (62.0 and 44.0 g/kg), (5) an excess of Ile and Val (44.0 and 50.0 g/kg), and (6) an excess of Leu and Val (62.0 and 50.0 g/kg). Excess levels of Leu, Ile and Val corresponded to 200% of the amount found in a diet with 350 g/kg CP provided by RDM. Red drum juveniles were stocked in 38-L glass aquaria (12 fish/aquarium), and diets were fed to fish in triplicate aquaria at a rate approaching apparent satiation, twice daily, for 49 d. At the end of the feeding trial, growth performance parameters were calculated and the postprandial concentration of BCAAs in plasma was analyzed. Growth performance of the red drum was significantly affected by an excess of dietary Leu, alone or in combination (Leu+Ile and Leu+Val), confirming an antagonistic effect due to the imbalanced concentration of BCAAs in the diet. In addition, the postprandial concentration of plasma Leu, Ile and/or Val was significantly higher in fish fed an excess of Leu, Ile and/or Val, respectively. Nonetheless, postprandial levels of BCAAs in plasma did not indicate that an excess of Leu blocked the intestinal absorption or promoted the catabolism of Ile and/or Val in red drum, as has been reported in other species.
Ultimately, the results obtained from this dissertation will facilitate the production of aquaculture feeds composed of alternative protein ingredients while maintaining an ideal AA profile for optimal performance of red drum
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