892 research outputs found
«Los Cinco Sentidos» en el Museo del Prado
El artículo propone un extenso comentario y análisis crítico de la exposición «Los Cinco Sentidos y el Arte», que tuvo lugar en el Museo del Prado del 27 de febrero al 4 de mayo de 1997, proveniente de la celebrada en Cremona en 1996 con el título «Immagini del sentire», y que reunió un considerable número de piezas -no sólo cuadros y grabados, sino también objetos de uso cotidiano, ilustraciones de libros e instrumentos científicos y musicales- con la voluntad de rastrear la presencia del motivo de los sentidos en el arte, principalmente el de los siglos XVI y XVII. Tras elogiar tanto la originalidad y el atractivo del tema de la exposición, como la calidad de las obras que ésta reunió, el artículo constata los problemas de planteamiento presentes en los comentarios de buena parte de las obras, así como algunas incoherencias en la selección ofrecida por la exposición española y, finalmente, la significativa pobreza de un catálogo demasiado limitado, tanto por lo que se refiere al repertorio de ilustraciones como por lo que atañe a los ensayos que presenta.The article provides an extensive commentary and critical analysis of the exhibition Los Cinco Sentidos y el Arte («The Five Senses and the Arts»), that took place at the Museo del Prado in 1997, coming from the one held in Cremona in 1996 which ran under the title Immagini del sentire. The Madrid exhibition brought together a considerable number of exhibits, not only paintings and engravings, but also objects of daily use, book illustrations and scientific and musical instruments, in an attempt to trace the subject of the senses in the Arts with a main emphasis on the XVIth and XVIIth centuries. After praising both the exhibition's originality and its thematic attraction as well as the high quality of the exhibits, the article does point out the problems of approach which seem tu surface the commentaries of a big part of the works as well as a certain incoherence in the selection which the Spanish exhibition offered and, finally, the significant shortcomings of an all too limited catalogue, both illustration wise as well as with regard to the essays it contains
New hydroacoustic and core data reveal sediment transport patterns off Uruguay
Submarine landslides cause slope instabilities and might damage sea-floor infrastructure or even generate tsunami waves. Therefore it is of major importance to understand all processes related to gravity-driven mass wasting and slope stability at continental margins. New swath bathymetry and parametric echo-sounding data from the Uruguay shelf and slope north-east of the Rio de la Plata were collected during METEOR Cruise M78/3. These data are investigated in order to understand mass wasting and sedimentary transport processes at the margin off Uruguay. Large amounts of silty suspension freight are delivered from the Rio de la Plata estuary. These sediments are potentially unstable, leading to numerous mass transport units in the working area.
Prominent features identified in the study include slide deposits, channels and several prominent escarpment structures. The situation is complicated by intensive slope parallel sediment transport due to strong contour currents. Our data indicate interaction between gravity-driven downslope transport and alongslope sediment transport. Contourite deposits in the headwall areas of mass wasting events suggest widespread weak layers at those deposits. The up to 70m-high headwalls, are focusing contour currents resulting in small alongslope channels. Future work will concentrate on the reconstruction of the geological/sedimentological history of the study area in order assess slope stability and sediment transport in greater detail
Towards a foundation for holistic power system validation and testing
Renewable energy sources and further electrificationof energy consumption are
key enablers for decreasing green-house gas emissions, but also introduce
increased complexitywithin the electric power system. The increased
availability ofautomation, information and communication technology,
andintelligent solutions for system operation have transformed thepower system
into a smart grid. In order to support thedevelopment process of smart grid
solutions on the system level,testing has to be done in a holistic manner,
covering the multi-domain aspect of such complex systems. This paper
introducesthe concept of holistic power system testing and discuss first
stepstowards a corresponding methodology that is being developed inthe European
ERIGrid research infrastructure project.Comment: 2016 IEEE 21st International Conference on Emerging Technologies and
Factory Automation (ETFA
Submarine slope failure offshore Uruguay - first results
New geophysical acquired during cruise M78 with RV “Meteor” in 2009 reveal a large-scale slope failure complex. Positioned between 1800 and 3300 m water depth, the slope failure affected an area of at least 1200 km2. The failure is hosted in contouritic deposits. The morphology of the up 70 m high headwalls is underlain by a deeper reflector which we interpret as detachment. Listric faults positioned upslope these headwalls root in this detachment and are precursor of future failure at this location. The detachment correlates with a regional BSR mapped by Uruguayan colleagues. Cores recovered from 3 transects across the failure complex confirm that the acoustic transparent units are debrites. Sedimentological evidence in accordance with hydro-acoustic data indicate that debrites deposited downslope this failure complex are recent features on the slope
Sediment dynamics and geohazards offshore Uruguay and northern Argentina: first results from the multi-disciplinary Meteor-cruise M78-3
About 90% of the sediments generated by weathering and erosion on land get finally deposited at the ocean margins. The sediment distribution processes and landscape evolution on land are relatively well understood, but comparably little is known about the role and relative importance of marine sediment dynamics in controlling the architectural evolution of ocean margins. Important players include hemi-pelagic settling, down-slope and current-controlled along-slope sediment transport, depositional and post-depositional sedimentary processes (e.g. consolidation and diagenesis), as well as the destabilization of sediment bodies and their erosion. Submarine landslides in this context thus may represent an important sediment transport process, but also a major geo-hazard due to the increasing number of offshore constructions as well as their potential to instantaneously displace large water masses triggering waves in densely populated coastal areas.
Here we present first results from a seagoing expedition that aimed at investigating the interaction processes of sediment redistribution, partitioning, deposition and diagenesis from the coast to the deep-sea along the western
South-Atlantic passive continental margin. During RV Meteor Cruise M78/3 in May-July 2009 the shelf, slope and rise offshore Argentina and Uruguay have been investigated by means of hydroacoustic and seismic mapping as well as geological sampling with conventional coring tools as well as the new MARUM seafloor drill rig (MeBo) that revealed recovery of geological strata sampled from up to 50m below seafloor.
The working area is characterized by a high amount of fluvial input by the Rio de la Plata river. The continental
slope is relatively wide and shows average slope gradients between 1 and 2.5 but locally higher slope gradients may occur (>5). The transition for the continental rise with low slope gradients is found in ~3000 m water depth. The working area is located in a highly dynamic oceanographic regime. Cold Antarctic water masses of the northward flowing Malvina current meet warm water masses of the southward flowing Brazil current in the working area.
Various types of sediment instabilities have been imaged in geophysical and core data, documenting particularly the continental slope offshore Uruguay to be locus of frequent submarine landslides. Apart from individual landslides, however, gravitational downslope sediment transport along the continental slope is restricted to the prominent Mar del Plata Canyon and possibly to smaller canyons indentified in the bathymetric data. The location of the canyons might be controlled by tectonics. In contrast, many morphological features (e.g. progradational terraces and slope parallel scarps with scour-geometries) reveal that sediment transport is predominantly influenced/controlled by strong contour bottom currents. This suggests a significant impact of the western boundary currents on the overall architectural evolution of the margin.
Future studies using the acquired geophysical, sedimentological, physical property and geochemical data will (i) quantify the relative contribution of gravitational down-slope vs. along-slope processes through time in shaping this ocean margin and how it relates to the global ocean circulation pattern and sea-level change through time, (ii) investigate depositional and post-depositional processes and how they control submarine slope stability and submarine landslide initiation and (iii) explore the interaction and relative contribution of the various processes in controlling margin evolution, sediment dynamics and geohazard off Uruguay and Northern Argentina
Phosphorylation/dephosphorylation of the beta-adrenergic receptor regulates its functional coupling to adenylate cyclase and subcellular distribution.
Prolonged exposure of cells or tissues to drugs or hormones such as catecholamines leads to a state of refractoriness to further stimulation by that agent, known as homologous desensitization. In the case of the beta-adrenergic receptor coupled to adenylate cyclase, this process has been shown to be intimately associated with the sequestration of the receptors from the cell surface through a cAMP-independent process. Recently, we have shown that homologous desensitization in the frog erythrocyte model system is also associated with increased phosphorylation of the beta-adrenergic receptor. We now provide evidence that the phosphorylation state of the beta-adrenergic receptor regulates its functional coupling to adenylate cyclase, subcellular translocation, and recycling to the cell surface during the process of agonist-induced homologous desensitization. Moreover, we show that the receptor phosphorylation is reversed by a phosphatase specifically associated with the sequestered subcellular compartment. At 23 degrees C, the time courses of beta-adrenergic receptor phosphorylation, sequestration, and adenylate cyclase desensitization are identical, occurring without a lag, exhibiting a t1/2 of 30 min, and reaching a maximum at approximately 3 hr. Upon cell lysis, the sequestered beta-adrenergic receptors can be partially recovered in a light membrane vesicle fraction that is separable from the plasma membranes by differential centrifugation. The increased beta-adrenergic receptor phosphorylation is apparently reversed in the sequestered vesicle fraction as the sequestered receptors exhibit a phosphate/receptor stoichiometry that is similar to that observed under basal conditions. High levels of a beta-adrenergic receptor phosphatase activity appear to be associated with the sequestered vesicle membranes. The functional activity of the phosphorylated beta-adrenergic receptor was examined by reconstituting purified receptor with its biochemical effector the guanine nucleotide regulatory protein (Ns) in phospholipid vesicles and assessing the receptor-stimulated GTPase activity of Ns. Compared to controls, phosphorylated beta-adrenergic receptors, purified from desensitized cells, were less efficacious in activating the Ns GTPase activity. These results suggest that phosphorylation of the beta-adrenergic receptor leads to its functional uncoupling and physical translocation away from the cell surface into a sequestered membrane domain. In the sequestered compartment, the phosphorylation is reversed thus enabling the receptor to recycle back to the cell surface and recouple with adenylate cyclase
Intracellular localization of the BCL-2 family member BOK and functional implications
The pro-apoptotic BCL-2 family member BOK is widely expressed and resembles the multi-BH domain proteins BAX and BAK based on its amino acid sequence. The genomic region encoding BOK was reported to be frequently deleted in human cancer and it has therefore been hypothesized that BOK functions as a tumor suppressor. However, little is known about the molecular functions of BOK. We show that enforced expression of BOK activates the intrinsic (mitochondrial) apoptotic pathway in BAX/BAK-proficient cells but fails to kill cells lacking both BAX and BAK or sensitize them to cytotoxic insults. Interestingly, major portions of endogenous BOK are localized to and partially inserted into the membranes of the Golgi apparatus as well as the endoplasmic reticulum (ER) and associated membranes. The C-terminal transmembrane domain of BOK thereby constitutes a 'tail-anchor' specific for targeting to the Golgi and ER. Overexpression of full-length BOK causes early fragmentation of ER and Golgi compartments. A role for BOK on the Golgi apparatus and the ER is supported by an abnormal response of Bok-deficient cells to the Golgi/ER stressor brefeldin A. Based on these results, we propose that major functions of BOK are exerted at the Golgi and ER membranes and that BOK induces apoptosis in a manner dependent on BAX and BAK
ERIGrid Holistic Test Description for Validating Cyber-Physical Energy Systems
Smart energy solutions aim to modify and optimise the operation of existing energy infrastructure. Such cyber-physical technology must be mature before deployment to the actual infrastructure, and competitive solutions will have to be compliant to standards still under development. Achieving this technology readiness and harmonisation requires reproducible experiments and appropriately realistic testing environments. Such testbeds for multi-domain cyber-physical experiments are complex in and of themselves. This work addresses a method for the scoping and design of experiments where both testbed and solution each require detailed expertise. This empirical work first revisited present test description approaches, developed a newdescription method for cyber-physical energy systems testing, and matured it by means of user involvement. The new Holistic Test Description (HTD) method facilitates the conception, deconstruction and reproduction of complex experimental designs in the domains of cyber-physical energy systems. This work develops the background and motivation, offers a guideline and examples to the proposed approach, and summarises experience from three years of its application.This work received funding in the European Community’s Horizon 2020 Program (H2020/2014–2020)
under project “ERIGrid” (Grant Agreement No. 654113)
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