Instalación eléctrica en baja tensión para complejo deportivo (Sarriguren-Navarra)

Este proyecto tiene por objeto indicar detalladamente las características técnicas que deberá cumplir la instalación eléctrica de un polideportivo, sito en Paseo de Champagnat de Sarriguren (Navarra), así como las prescripciones generales para la protección contra incendios de las personas, edificio e instalación. Al mismo tiempo y cumpliendo con la normativa vigente se pretende dar cuenta a los organismos competentes para solicitar los permisos necesarios para su ejecución. Tanto la redacción de este proyecto, como la ejecución física del mismo se realizaran de acuerdo con las instrucciones y normas descritas en los reglamentos siguientes: - Reglamento Electrotécnico de Baja Tensión. - Normas Técnicas de la Edificación (NTE-IE). - Reglamento de Seguridad contra Incendios (NBE-CPI-96). - Normas particulares de la empresa suministradora.Ingeniería Técnica IndustrialIndustria Ingeniaritza Tekniko

Literatura y realidad en la Venezuela de fin de siglo: Baedeker 2000

Baedeker 2000 es un libro de Andrés Eloy Blanco, que pertenece a la literatura venezolana de fin de siglo, no -obviamente por la fecha en que fue escrito (hacia 1930), sino por haber sido compuesto como predicción o vaticinio de la Venezuela inmediatamente posterior a 1999. Cuando fue escrito este artículo, en 1997, apenas faltarían dos años para llegar al tiempo profetizado por el poeta venezolano, y hoy se tiene la impresión de que Venezuela no alcanzará con facilidad, no al menos puntualmente, la primavera pronosticada. La realidad real no quiere obedecer a la realidad literaria. Baedeker 2000, con todo, no existe inútilmente. &nbsp

Synthesis of Unsymmetrical Bis(phosphine) Oxides and Their Phosphines via Secondary Phosphine Oxide Precursors

The unsymmetrical bidentate phosphine ligands (Me)2PCH2CH2CH2P(Et)2 (14), (Me)2PCH2CH2CH2P(iPr)2 (15), (Me)2PCH2CH2CH2P(Cy)2 (16), and (Me)2PCH2CH2CH2P(Ph)2 (17) were synthesized using air–stable phosphine oxide intermediates. In the first step, sodium phosphinites formed by deprotonation of (Me)2P(O)H, (Et)2P(O)H, and (iPr)2P(O)H were alkylated by 1-bromo-3-chloropropane. The different substitution rates of the chloride and bromide groups allowed the isolation of the intermediates (Me)2P(O)CH2CH2CH2Cl (2), (Et)2P(O)CH2CH2CH2Cl (3), and (iPr)2P(O)CH2CH2CH2Cl (4). Subsequent reaction of (Me)2P(O)CH2CH2CH2Cl (2) with the sodium phosphinites generated from (Et)2P(O)H, (iPr)2P(O)H, (tBu)2P(O)H, (Cy)2P(O)H, or (Ph)2P(O)H gave unsymmetrical bidentate phosphine oxides; reduction of these oxides yielded the unsymmetrical phosphines. The unsymmetrical bidentate phosphines react with metal salts to form complexes. X-ray crystal structures of cis-Pt((Me)2P(CH2CH2CH2)P(iPr)2)Cl2 (20) and racemic [CuI((Me)2P(CH2CH2CH2)P(Ph)2)]Cl (21) were obtained. The kinetics and scope of the synthetic route were also explored. Experiments showed that the rate of substitution of the alkyl chloride group in (R)2P(O)CH2CH2CH2Cl-type oxides increases relative to unsubstituted alkyl chlorides due to the presence of the phosphonyl group on one end of the molecule. The scope of the reaction involving 1,2-dihaloalkanes was also investigated, and it was found that the reaction mixture of sodium dimethylphosphinite and 1,2-dihaloalkanes formed tetramethylbis(phosphine) monoxide (22), which decomposes on work-up to give complex reaction mixtures

Hydrothermal liquefaction of biomass as one of the most promising alternatives for the synthesis of advanced liquid biofuels: a review

The use of biofuels offers advantages over existing fuels because they come from renewable sources, they are biodegradable, their storage and transport are safer, and their emissions into the atmosphere are lower. Biomass is one of the most promising sustainable energy sources with a wide variety of organic materials as raw material. Chemical, biochemical, and thermochemical methods have been proposed to obtain biofuels from raw materials from biomass. In recent years, a thermochemical method that has generated great interest is hydrothermal liquefaction. In this paper, a brief review of the main sources for liquid biofuels and the synthesis processes is presented, with special emphasis on the production of biofuels using hydrothermal liquefaction by using waste generated by human activity as raw material.The authors are grateful for financial support from the Spanish Ministry of Science and Innovation (AEI/MINECO) and the Government of Navarra through projects PID2020-112656RB-C21 and PC034-035 BIOGASOLANA. AG also thanks Santander Bank for funding via the Research Intensification Program

Analysis by temperature-programmed reduction of the catalytic system Ni-Mo-Pd/Al2O3

Alumina-supported nickel catalysts are used to facilitate many reactions at various scales. However, the deactivation of these catalysts is an important problem that has prompted the search for solutions such as the addition of other metals that act as promoters. In this research, the interactions that form between the support and the metals have been studied, a fundamental property that directly affects the performance of the catalyst. With this idea, several Ni-Pd and Ni-Mo bimetallic and various Ni-Mo-Pd trimetallic samples have been prepared, and the reduction capacity of the oxide phases by temperatura-programmed reduction has been analyzed and studied. It has been found that in bimetallic catalysts, Pd favors the appearance of NiO species that are more easily reducible than Mo. In the same way, the data obtained from the trimetallic simples suggest that the impregnation order of Mo and Pd is not a determining factor in these catalysts. In addition, it has been found that the co-impregnation of Ni with Pd gives better results than the sequential impregnation of these metals. The results obtained have also shown that the order of nickel impregnation is decisive. In the case of Ni-Mo catalysts, by impregnating the molybdenum first, catalysts with better reducing properties can be obtained.The authors are grateful for financial support from the Spanish Ministry of Science and Innovation (AEI/MINECO) and the Government of Navarra through projects PID2020-112656RB-C21 and PC034-035 BIOGASOLANA. Open access funding provided by Universidad Pública de Navarra. JJTH thanks Universidad Pública de Navarra for a postdoctoral grant. AG also thanks Santander Bank for funding via the Research Intensification Program

Propofol suppresses synaptic responsiveness of somatosensory relay neurons to excitatory input by potentiating GABA(A )receptor chloride channels

Propofol is a widely used intravenous general anesthetic. Propofol-induced unconsciousness in humans is associated with inhibition of thalamic activity evoked by somatosensory stimuli. However, the cellular mechanisms underlying the effects of propofol in thalamic circuits are largely unknown. We investigated the influence of propofol on synaptic responsiveness of thalamocortical relay neurons in the ventrobasal complex (VB) to excitatory input in mouse brain slices, using both current- and voltage-clamp recording techniques. Excitatory responses including EPSP temporal summation and action potential firing were evoked in VB neurons by electrical stimulation of corticothalamic fibers or pharmacological activation of glutamate receptors. Propofol (0.6 – 3 μM) suppressed temporal summation and spike firing in a concentration-dependent manner. The thalamocortical suppression was accompanied by a marked decrease in both EPSP amplitude and input resistance, indicating that a shunting mechanism was involved. The propofol-mediated thalamocortical suppression could be blocked by a GABA(A )receptor antagonist or chloride channel blocker, suggesting that postsynaptic GABA(A )receptors in VB neurons were involved in the shunting inhibition. GABA(A )receptor-mediated inhibitory postsynaptic currents (IPSCs) were evoked in VB neurons by electrical stimulation of the reticular thalamic nucleus. Propofol markedly increased amplitude, decay time, and charge transfer of GABA(A )IPSCs. The results demonstrated that shunting inhibition of thalamic somatosensory relay neurons by propofol at clinically relevant concentrations is primarily mediated through the potentiation of the GABA(A )receptor chloride channel-mediated conductance, and such inhibition may contribute to the impaired thalamic responses to sensory stimuli seen during propofol-induced anesthesia

Intrinsic plasticity complements long-term potentiation in parallel fiber input gain control in cerebellar Purkinje cells

Synaptic gain control and information storage in neural networks are mediated by alterations in synaptic transmission, such as in long-term potentiation (LTP). Here,weshowusingboth in vitroandin vivo recordingsfromthe rat cerebellum that tetanization protocols for the induction of LTP at parallel fiber (PF)-to-Purkinje cell synapsescanalsoevokeincreases in intrinsic excitability. Thisformof intrinsic plasticity shares with LTP a requirement for the activation of protein phosphatases 1, 2A, and 2B for induction. Purkinje cell intrinsic plasticity resembles CA1 hippocampal pyramidal cell intrinsic plasticity in that it requires activity of protein kinase A(PKA) and casein kinase 2 (CK2) and is mediated by a downregulation of SK-type calcium-sensitive K conductances. In addition, Purkinje cell intrinsic plasticity similarly results in enhanced spine calcium signaling. However, there are fundamental differences: first, while in the hippocampus increases in excitability result in a higher probability for LTP induction, intrinsic plasticity in Purkinj

GlyT2+ Neurons in the Lateral Cerebellar Nucleus

The deep cerebellar nuclei (DCN) are a major hub in the cerebellar circuitry but the functional classification of their neurons is incomplete. We have previously characterized three cell groups in the lateral cerebellar nucleus: large non-GABAergic neurons and two groups of smaller neurons, one of which express green fluorescence protein (GFP) in a GAD67/GFP mouse line and is therefore GABAergic. However, as a substantial number of glycinergic and glycine/GABA co-expressing neurons have been described in the DCN, this classification needed to be refined by considering glycinergic neurons. To this end we took advantage of a glycine transporter isoform 2 (GlyT2)-eGFP mouse line that allows identification of GlyT2-expressing, presumably glycinergic neurons in living cerebellar slices and compared their electrophysiological properties with previously described DCN neuron populations. We found two electrophysiologically and morphologically distinct sets of GlyT2-expressing neurons in the lateral cerebellar nucleus. One of them showed electrophysiological similarity to the previously characterized GABAergic cell group. The second GlyT2+ cell population, however, differed from all other so far described neuron types in DCN in that the cells (1) are intrinsically silent in slices and only fire action potentials upon depolarizing current injection and (2) have a projecting axon that was often seen to leave the DCN and project in the direction of the cerebellar cortex. Presence of this so far undescribed DCN neuron population in the lateral nucleus suggests a direct inhibitory pathway from the DCN to the cerebellar cortex

Origin of Active States in Local Neocortical Networks during Slow Sleep Oscillation

Slow-wave sleep is characterized by spontaneous alternations of activity and silence in corticothalamic networks, but the causes of transition from silence to activity remain unknown. We investigated local mechanisms underlying initiation of activity, using simultaneous multisite field potential, multiunit recordings, and intracellular recordings from 2 to 4 nearby neurons in naturally sleeping or anesthetized cats. We demonstrate that activity may start in any neuron or recording location, with tens of milliseconds delay in other cells and sites. Typically, however, activity originated at deep locations, then involved some superficial cells, but appeared later in the middle of the cortex. Neuronal firing was also found to begin, after the onset of active states, at depths that correspond to cortical layer V. These results support the hypothesis that switch from silence to activity is mediated by spontaneous synaptic events, whereby any neuron may become active first. Due to probabilistic nature of activity onset, the large pyramidal cells from deep cortical layers, which are equipped with the most numerous synaptic inputs and large projection fields, are best suited for switching the whole network into active state

Origin of Active States in Local Neocortical Networks during Slow Sleep Oscillation

Slow-wave sleep is characterized by spontaneous alternations of activity and silence in corticothalamic networks, but the causes of transition from silence to activity remain unknown. We investigated local mechanisms underlying initiation of activity, using simultaneous multisite field potential, multiunit recordings, and intracellular recordings from 2 to 4 nearby neurons in naturally sleeping or anesthetized cats. We demonstrate that activity may start in any neuron or recording location, with tens of milliseconds delay in other cells and sites. Typically, however, activity originated at deep locations, then involved some superficial cells, but appeared later in the middle of the cortex. Neuronal firing was also found to begin, after the onset of active states, at depths that correspond to cortical layer V. These results support the hypothesis that switch from silence to activity is mediated by spontaneous synaptic events, whereby any neuron may become active first. Due to probabilistic nature of activity onset, the large pyramidal cells from deep cortical layers, which are equipped with the most numerous synaptic inputs and large projection fields, are best suited for switching the whole network into active state