78 research outputs found
Technical criteria for the desing of foundation slabs and perimetral wall in difficult terrain in Madrid. Spain
This paper explains a procedure for the choice of ballast modules used for the design of direct continuous foundation in karst terrain. The presence of dangerous cavities is introduced in this procedure thereby evaluating risk failure. It also provides pertinent guidelines to direct the geotechnical survey of the terrain
El complejo de playa-lagoon de Corrubedo y los submedios característicos. Galicia, NW. España
El complejo costero de Corrubedo (Provincia de La Coruña) es un sistema playa-barrera-lagoon, en avanzado estado de evolución. En el presente trabajo se distinguen 8 subambientes de sedimentación y se describen los procesos actuantes y los sedimentos característicos de cada uno de ellos. Se distinguen también las etapas de evolución en época reciente del sistema, y se proponen los posibles mecanismos que la causaron
The siliciclastic Permian-Triassic deposits in Central and Northeastern Iberian Peninsula (Iberian, Ebro and Catalan Basins) : a proposal for correlation
The siliciclastic deposits of the Iberian, Ebro and Catalan Basins have been described for more than a century, but facies similarities and a lack of biostratigaphic data have difficulted the correlation of the local stratigraphic units in a general framework up to now. Combining pollen and spores data, the identification of the regional unconformities and hiatuses and the quantitative analysis of the subsidence by backstripping methods, a new correlation scheme for these facies is proposed
El complejo de playa-lagoon de Corrubedo y los submedios característicos. Galicia, NW. España
El complejo costero de Corrubedo (Provincia de La Coruña) es un sistema playa-barrera-lagoon, en avanzado estado de evolución. En el presente trabajo se distinguen 8 subambientes de sedimentación y se describen los procesos actuantes y los sedimentos característicos de cada uno de ellos. Se distinguen también las etapas de evolución en época reciente del sistema, y se proponen los posibles mecanismos que la causaron
Hypocholesterolemic and Hepatoprotective Effects of “Triguero” Asparagus from Andalusia in Rats Fed a High Cholesterol Diet
The cultivated species of the wild autochthonous Asparagus officinalis in Andalusia in Spain is commonly called “triguero” asparagus. This vegetable has traditionally been very much appreciated for its organoleptic and nutritional characteristics. This study has been designed to evaluate the potential effect of different concentrations of freeze-dried asparagus (500, 250, and 125 mg/Kg of body weight/day) on oxidative status and lipid profile in rats fed a cholesterol-rich diet. After five weeks of treatment, doses of 250 and 500 mg/Kg of asparagus were able to significantly reduce total cholesterol and LDL cholesterol levels. Atherogenic index was also significantly reduced in a dose-dependent manner by administrating freeze-dried asparagus. A beneficial effect was observed in the HDL cholesterol levels in asparagus-fed groups although the increase was not significant. Consumption of asparagus also improved antioxidant status, assayed superoxide dismutase (SOD) and catalase (CAT) enzymes, and protected against lipid peroxidation. These results show that the intake of green asparagus from Andalusia (Spain) helps to regulate plasma lipid levels and prevents oxidative damage in hypercholesterolemic conditions
The siliciclastic Permian-Triassic deposits in Central and Northeastern Iberian Peninsula (Iberian, Ebro and Catalan Basins): a proposal for correlation
The siliciclastic deposits of the Iberian, Ebro and Catalan Basins have been described for more than a century, but facies similarities and a lack of biostratigaphic data have difficulted the correlation of the local stratigraphic units in a general framework up to now. Combining pollen and spores data, the identification of the regional unconformities and hiatuses and the quantitative analysis of the subsidence by backstripping methods, a new correlation scheme for these facies is proposed
Quantifying orbital Rashba effect via harmonic Hall torque measurements in transition-metal|Cu|Oxide structures
Spin-orbit interaction (SOI) plays a pivotal role in the charge-to-spin
conversion mechanisms, notably the spin Hall effect involving spin-dependent
deflection of conduction electrons and the interfacial spin Rashba-Edelstein
effect. In recent developments, significant current-induced torques have been
predicted and observed in material systems featuring interfaces with light
elements \textit{i.e.} possessing a weak SOI. These findings challenge existing
mechanisms and point to the potential involvement of the orbital counterpart of
electrons, namely the orbital Hall and orbital Rashba effects. Here, we
establish, in Pt|Co|Cu|AlOx stacking, the comparable strength between the
orbital Rashba effect at the Cu|AlOx interface and the effective spin Hall
effect in Pt|Co. Subsequently, we investigate the thickness dependence of an
intermediate Pt layer in Co|Pt|Cu|CuOx, revealing the strong signature of the
orbital Rashba effect at the Cu|CuOx interface besides the well-identified Pt
intrinsic spin Hall effect. Leveraging such contribution from the orbital
Rashba effect, we show a twofold enhancement in the effective torques on Co
through harmonic Hall measurements. This result is corroborated by
complementary spin Hall magneto-resistance and THz spectroscopy experiments.
Our results unveil unexplored aspects of the electron's orbital degree of
freedom, offering an alternative avenue for magnetization manipulation in
spintronic devices with potential implications for energy-efficient and
environmentally friendly technologies using abundant and light elements.Comment: 11 pages, 5 figure
Interfacing Neurons with Nanostructured Electrodes Modulates Synaptic Circuit Features
Understanding neural physiopathology requires advances in nanotechnology-based interfaces, engineered to monitor the functional state of mammalian nervous cells. Such interfaces typically contain nanometer-size features for stimulation and recording as in cell-non-invasive extracellular microelectrode arrays. In such devices, it turns crucial to understand specific interactions of neural cells with physicochemical features of electrodes, which could be designed to optimize performance. Herein, versatile flexible nanostructured electrodes covered by arrays of metallic nanowires are fabricated and used to investigate the role of chemical composition and nanotopography on rat brain cells in vitro. By using Au and Ni as exemplary materials, nanostructure and chemical composition are demonstrated to play major roles in the interaction of neural cells with electrodes. Nanostructured devices are interfaced to rat embryonic cortical cells and postnatal hippocampal neurons forming synaptic circuits. It is shown that Au-based electrodes behave similarly to controls. Contrarily, Ni-based nanostructured electrodes increase cell survival, boost neuronal differentiation, and reduce glial cells with respect to flat counterparts. Nonetheless, Au-based electrodes perform superiorly compared to Ni-based ones. Under electrical stimulation, Au-based nanostructured substrates evoke intracellular calcium dynamics compatible with neural networks activation. These studies highlight the opportunity for these electrodes to excite a silent neural network by direct neuronal membranes depolarization
Pharmacological effects of mitraphylline from Uncaria tomentosa in primary human monocytes: Skew toward M2 macrophages
© 2015 Elsevier Ireland Ltd. All rights reserved. Ethnopharmacological relevance Uncaria tomentosa (Willdenow ex Roemer & Schultes) DC. (Rubiaceae) is a Peruvian thorny liana, commonly known as >cat's claw>, and traditionally used in folk medicine to deal with several inflammatory diseases. Mitraphylline (MTP) is the most abundant pentacyclic oxindolic alkaloid (POA) from U. Tomentosa and has been reported to modify the inflammatory response. Herein, we have sought to identify the mechanisms underlying this modulatory effect of MTP on primary human monocytes and its ability to regulate differentiation processes on human primary monocyte and monocyte-derived macrophages. Material and methods In vitro studies with human primary monocytes and monocyte-derived macrophages were performed. Monocytes and M0 macrophages were exposed to MTP (25 μM) and LPS (100 ng/mL). M0 macrophages were polarized to M1 and M2 phenotypes in the absence or presence of MTP. The activation state of monocytes/macrophages was assessed by flow cytometry, gene expression and protein analysis of different specific markers. Results In human primary monocytes, the incubation of MTP for 24 h reduced the number of classical (CD14++CD16-) and intermediate (CD14++CD16+) subsets when compared to untreated or LPS-treated cells. MTP also reduced the chemotactic capacity of human primary monocytes. In addition, MTP promoted the polarization of M0 macrophages toward an anti-inflammatory M2 phenotype, the abrogation of the release of pro-inflammatory cytokines such as TNFα, IL-6 or IL-1β, as well as the restoration of markers for M2 macrophages in LPS-treated M1 macrophages. Conclusions Our results suggest that MTP may be a key modulator for regulating the plasticity of monocytes/macrophages and the attenuation of the inflammatory response.This work was supported by the University of Seville, “V Own Research Plan” contract to BB and QA. MS has the benefit of a FPI fellowship (BES-2012–056104) of MICINN.Peer Reviewe
Polystyrene Nanopillars with Inbuilt Carbon Nanotubes Enable Synaptic Modulation and Stimulation in Interfaced Neuronal Networks
The use of nanostructured materials and nanosized-topographies has the potential to impact the performance of implantable biodevices, including neural interfaces, enhancing their sensitivity and selectivity, while reducing tissue reactivity. As a result, current trends in biosensor technology require the effective ability to improve devices with controlled nanostructures. Nanoimprint lithography to pattern surfaces with high-density and high aspect ratio nanopillars (NPs) made of polystyrene (PS-NP, insulating), or of a polystyrene/carbon-nanotube nanocomposite (PS-CNT-NP, electrically conductive) are exploited. Both substrates are challenged with cultured primary neurons. They are demonstrated to support the development of suspended synaptic networks at the NPs’ interfaces characterized by a reduction in proliferating neuroglia, and a boost in neuronal emergent electrical activity when compared to flat controls. The authors successfully exploit their conductive PS-CNT-NPs to stimulate cultured cells electrically. The ability of both nanostructured surfaces to interface tissue explants isolated from the mouse spinal cord is then tested. The integration of the neuronal circuits with the NP topology, the suspended nature of the cultured networks, the reduced neuroglia formation, and the higher network activity together with the ability to deliver electrical stimuli via PS-CNT-NP reveal such platforms as promising designs to implement on neuro-prosthetic or neurostimulation devices
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