The Quest for Palladium-Catalysed Alkyl-Nitrogen Bond Formation

Our interest in the development of transition-metal catalysis for the realisation of vicinal diamination reactions of alkenes started about a decade ago. A number of successful transformations in this area have been developed using palladium catalysis. As a challenging aspect of major importance, the palladium-catalysed coupling of alkyl–nitrogen bonds constitutes the second step in diaminations of alkenes. We here discuss the details that led us to consider high-oxidation-state palladium catalysis as a key feature in such C–N bond-forming reactions. This work discusses both our own contributions and the ones from colleagues and combines the discussion of catalytic reactions and stoichiometric control experiments. It demonstrates that reductive alkyl–nitrogen bond formation from palladium(IV) proceeds with a low activation barrier and through a linear transition state of nucleophilic displacement

High Gain Amplifier with Enhanced Cascoded Compensation

A two-stage CMOS operational amplifier with both, gain-boosting and indirect current feedback frequency compensation performed by means of regulated cascode amplifiers, is presented. By using quasi-floating-gate transistors (QFGT) the supply requirements, the number of capacitors and the size of the compensation capacitors respect to other Miller schemes are reduced. A prototype was fabricated using a 0.5 μm technology, resulting, for a load of 45 pF and supply voltage of 1.65 V, in open-loop-gain of 129 dB, 23 MHz of gain-bandwidth product, 60o phase margin, 675 μW power consumption and 1% settling time of 28 ns

1.5V fully programmable CMOS Membership Function Generator Circuit with proportional DC-voltage control

A Membership Function Generator Circuit (MFGC) with bias supply of 1.5 Volts and independent DC-voltage programmable functionalities is presented. The realization is based on a programmable differential current mirror and three compact voltage-to-current converters, allowing continuous and quasi-linear adjustment of the center position, height, width and slopes of the triangular/trapezoidal output waveforms. HSPICE simulation results of the proposed circuit using the parameters of a double-poly, three metal layers, 0.5 μm CMOS technology validate the functionality of the proposed architecture, which exhibits a maximum deviation of the linearity in the programmability of 7 %

Characterization of neutrino signals with radiopulses in dense media through the LPM effect

We discuss the possibilities of detecting radio pulses from high energy showers in ice, such as those produced by PeV and EeV neutrino interactions. It is shown that the rich radiation pattern structure in the 100 MHz to few GHz allows the separation of electromagnetic showers induced by photons or electrons above 100 PeV from those induced by hadrons. This opens up the possibility of measuring the energy fraction transmitted to the electron in a charged current electron neutrino interaction with adequate sampling of the angular distribution of the signal. The radio technique has the potential to complement conventional high energy neutrino detectors with flavor information.Comment: 5 pages, 4 ps figures. Submitted to Phys. Rev. Let

Los marcos informativos del cannabis en la prensa española. Evidencia empírica desde la teoría del framing = Kalamuaren informazio-eremuak Espainiako prentsan. Ebidentzia enpirikoa framingaren teoriatik = Cannabis news frames in the spanish press. Applicattion of the theory of framing

Partiendo de la perspectiva del framing o enmarcado, se analizó mediante herramientas estadísticas una muestra de artículos de la prensa española sobre el cannabis, droga de comercio ilegal más consumida en el mundo. Las informaciones sobre el cannabis son presentadas mayoritariamente mediante el género de la noticia, sin contrastar y sin contextualizar. El enmarcado del cannabis presenta un reparto fijo de papeles –cada actor realiza casi siempre una misma acción– que resulta favorable a determinadas fuentes (policía, jueces, políticos). Además, los individuos son los responsables de los problemas en torno al cannabis, mientras que corresponde resolverlos a las instituciones. LABURPENA Framing-aren ikuspegitik abiatuta, Espainiako prentsak kalamuari buruz –munduan legez aurkako salerosketa duen kontsumo handieneko droga– argitaratutako artikuluen lagin bat aztertu da tresna estatistikoen bitartez. Kalamuari buruz argitaratutako informazio gehienak albiste-generoaren bitartez aurkezten dira, kontrasterik edo testui ngururik gabe. Kalamuaren informazio-eremuak rolen banaketa finko bat aurkezten du –aktore bakoitzak ekintza berdina egiten du ia beti– iturri batzuen mesedetan (polizia, epaileak, politikoak). Halaber, gizabanakoa da kalamuaren inguruan sortzen diren arazoen erantzule, baina konponbidea erakundeei dagokie. ABSTRACT The news frames used by the Spanish press to inform about the cannabis present a fixed role-casting where each actor plays almost always the same action, that is assessed almost always in the same way. This role-casting works in favor of certain news sources and actors (the Police, the Law, politicians) who are used to give a possitive image of themselves, whilst other actors (cannabis consumers) are only used to give a negative image of themselves. Besides, individuals were responsible for causing the problems about cannabis, whereas the institutions had the responsability for solving them