Modelo experimental de colocación de catéter intratecal lumbar para anestesia espinal en perros

Aunque existe controversia entre Corning y Bier, el primer caso de anestesia espinal se publica en el año 1885, cuando Cornig, accidentalmente, realiza un bloqueo espinal en un perro con cocaína. Desde entonces, la anestesia espinal probablemente ha sido la técnica regional más comúnmente utilizada en la moderna anestesia. Aunque se ha escrito mucho en lo relativo a dicha técnica: aplicaciones, complicaciones..., son pocos los estudios controlados, particularmente en animales donde ha sido posible mantener unas condiciones experimentales estandarizadas. Aún así, han sido descritos métodos experimentales de anestesia espinal 6-11 y epidural12-19 usando la implantación de catéteres en el perro, gato, oveja, rata y humanos. En la gran mayoría de los casos el acceso al espacio subaracnoideo se realiza quirúrgicamente vía occipital (se ha hecho en otras especies como en rata), llegando hasta la cisterna magna, donde puede quedar colocado el catéter, o bien prolongarlo hasta nivel torácico, lumbar. El presente estudio describe un modelo de implantación de catéter intradural en perros, con abordaje lumbar, con técnica quirúrgica previa y con control radioscópico

Dynamic characterisation of interlaminar fracture toughness in carbon fibre epoxy composite laminates

In this work, the rate dependence of mode I interlaminar fracture toughness for two different materials systems, IM7/8552 and IM7/M91, both unidirectional UD carbon-fibre epoxy composite laminates have been examined over a wide range of loading rates from 0.5 mm/min up to 2000 mm/s at room temperature. Quasi-static fracture tests were performed using a DCB (double-cantilever beam) method with a screw-driven testing machine, while the dynamic tests were carried out using a WIF (wedge-insert fracture) specimen loaded dynamically in a hydraulic system. For performing the tests at high displacement rates, a special setup was designed and manufactured which allowed the insertion of the wedge within the DCB specimens at different cross-head displacement rates. The experimental technique used a pair of strain gauges attached to the bending surface of one of the arms of the cantilever beams and far from the initial crack tip. The peak values of the recorded strain were used to determine the fracture toughness under dynamic conditions through use of the compliance calibration method. A finite element model was developed to check the consistency of the measurements and validate the data reduction method used. The results exhibited rate insensitive behaviour in the case of the IM7/8552 laminates while IM7/M91 showed the contrary behaviour with maximum peak at 500 mm/s of displacement rate, with a toughness increase of 95% with respect to the quasi-static conditions.The research leading to these results has received funding from the European Union as Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 722096, DYNACOMP project

Short-term effects of impurities in the CO2 stream injected into fractured carbonates.

After the Paris Agreement in which 195 countries are involved, the Carbon Capture and Storage (CCS) is now an accepted technology in the United Nations Framework Convention on Climate Change (UNFCCC). In Spain, Fundación Ciudad de la Energía (CIUDEN) has successfully completed the full CCS chain, being CO2 captured in the Technology Development Centre in Cubillos del Sil (León, Spain) whereas that it is geologically stored in a deep saline aquifer, formed by fractured carbonates with poor matrix porosity, located in the Technology Development Plant (TDP) at Hontomín (Burgos, Spain). The results of the field tests, in which up to 150 tons of CO2 and synthetic air (5 %v of N2 and O2) were co-injected on site, are analyzed in this paper comparing the operational parameters gained during the injection of impure CO2 (pressures, temperatures and flow ranges) with its corresponding baseline previously determined (i.e. 1,500 tons of pure CO2 were injected during the reservoir hydraulic characterization). Besides that, the geochemical reactivity analysis of impure CO2 injected in this saline aquifer and its correlation with the results from laboratory tests were assessed. As main conclusions from laboratory scale results, a porosity diminution was measured after the injection of CO2 with 5 %v of SO2; apart from that, without SO2, the effluent pH was in the range of 7-8 whereas in case of CO2 and SO2, a pH of 1-2 was obtained. Otherwise and focused on field scale tests, a density decrease was detected comparing the base case (pure CO2) with the CO2 injection containing 5.1 %v of synthetic air. On the other hand, Ca2+, SO42-, Mg2+ and K+ migration effects in the rock were also detected and analyzed

Photoluminescence Imaging and LBIC Characterization of Defects in mc-Si Solar Cells

Today's photovoltaic market is dominated by multicrystalline silicon (mc-Si) based solar cells with around 70% of worldwide production. In order to improve the quality of the Si material, a proper characterization of the electrical activity in mc-Si solar cells is essential. A full-wafer characterization technique such as photoluminescence imaging (PLi) provides a fast inspection of the wafer defects, though at the expense of the spatial resolution. On the other hand, a study of the defects at a microscopic scale can be achieved through the light-beam induced current technique. The combination of these macroscopic and microscopic resolution techniques allows a detailed study of the electrical activity of defects in mc-Si solar cells. In this work, upgraded metallurgical-grade Si solar cells are studied using these two techniques

Periodontal disease and diabetes : review of the literature

Aims: To provide updated knowledge on the relationship between periodontal disease and diabetes from an oral health perspective. Methods: A review of the English-language literature was performed, gathering articles on the two diseases published over the past 10 years. Results: Both diseases result from the confluence of various triggering and modifying factors, and there are inter-individual differences in the risk of their development. Recent research has shown that diabetes may increase the risk of periodontitis, and it has been proposed that chronic periodontal disease may influence the natural course of diabetes. There appears to be an association among oral infections, impaired sugar metabolism, and atherosclerosis, indicating a theoretical link between metabolic syndrome and periodontal disease. Clinical implications: Control of periodontal disease may enhance glycemic control in patients with type 2 diabetes. In turn, improved glycemic control may contribute to a better control of periodontal disease. © Medicina Oral S. L

Increased cerebrospinal fluid levels of cytokines monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1β (MIP-1β) in patients with amyotrophic lateral sclerosis

Introduction: Neuroinflammation has recently been described in amyotrophic lateral sclerosis (ALS). However, the precise role of such proinflammatory cytokines as monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1� (MIP-1�) in ALS has not yet been determined. In this study, we determined cerebrospinal fluid (CSF) MCP-1 and MIP-1� levels and assessed their association with the duration and severity of ALS. Methods: Concentrations of MCP-1 and MIP-1� were determined in the CSF of 77 patients diagnosed with ALS and 13 controls. Cytokine levels were analysed in relation to ALS duration ( 12 months) and severity ( 30 points on the ALS Functional Rating Scale administered at hospital admission). Results: Higher CSF MIP-1� (10.68 pg/mL vs 4.69 pg/mL, P < .0001) and MCP-1 (234.89 pg/mL vs 160.95 pg/mL, P = .011) levels were found in the 77 patients with ALS compared to controls. There were no differences in levels of either cytokine in relation to disease duration or severity. However, we did observe a significant positive correlation between MIP-1� and MCP-1 in patients with ALS. Conclusions: The increase in MIP-1� and MCP-1 levels suggests that these cytokines may havea synergistic effect on ALS pathogenesis. However, in our cohort, no association was found witheither the duration or the clinical severity of the disease

Evaluation of p53, Caspase-3, Bcl-2, and Ki-67 markers in oral squamous cell carcinoma and premalignant epithelium in a sample from Alava Province (Spain)

Objectives: The objective of this study was to determine whether alterations in the expression of p53, caspase-3 Bcl-2, and ki-67 appear early in premalignant oral epithelium and show clonal behavior. Study Design: Samples from 41 tumors with their adjacent non-tumor epithelia were immunohistochemically analyzed using monoclonal antibodies that recognize p53, caspase-3, Bcl-2, and Ki-67 Results: A statistically significant association was found between the expression in tumor and adjacent epithelium of p53, caspase-3, and Bcl-2 but not of k-67. A significant association was observed between the expression of ki-67 and p53 in both localizations. In non-tumor (premalignant) epithelium samples, there was a significant inverse relationship between the expressions of p53 and caspase-3 and a significant direct relationship between the expressions of p53 and Bcl-2. Conclusions: Alterations in these proteins appear to operate in combination with premalignant epithelia to create hyperproliferative cell states that favor the acquisition of summative oncogenic errors that confer invasive capacity

Synthesis and properties of 2′-deoxy-2′,4′-difluoroarabinose-modified nucleic acids

© 2015 American Chemical Society. We report the synthesis, thermal stability, and RNase H substrate activity of 2′-deoxy-2′,4′-difluoroarabino-modified nucleic acids. 2′-Deoxy-2′,4′-difluoroarabinouridine (2,′4′-diF-araU) was prepared in a stereoselective way in six steps from 2′-deoxy-2′-fluoroarabinouridine (2′-F-araU). NMR analysis and quantum mechanical calculations at the nucleoside level reveal that introduction of 4′-fluorine introduces a strong bias toward the North conformation, despite the presence of the 2′-βF, which generally steers the sugar pucker toward the South/East conformation. Incorporation of the novel monomer into DNA results on a neutral to slightly stabilizing thermal effect on DNA-RNA hybrids. Insertion of 2′,4′-diF-araU nucleotides in the DNA strand of a DNA-RNA hybrid decreases the rate of both human and HIV reverse transcriptase-associated RNase H-mediated cleavage of the complement RNA strand compared to that for an all-DNA strand or a DNA strand containing the corresponding 2′-F-araU nucleotide units, consistent with the notion that a 4′-fluorine in 2′-F-araU switches the preferred sugar conformation from DNA-like (South/East) to RNA-like (North).Peer Reviewe

Estudio económico de la reutilización de paneles solares en pequeñas instalaciones fotovoltaicas

CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMEN: La generación eléctrica a partir de energía solar es limpia, asequible y renovable. Por estos motivos, su aprovechamiento ha sufrido un importante crecimiento en los últimos años y se ha situado como la tercera fuente de generación de energía renovable con más peso en España. Las plantas de generación de energía fotovoltaica son cada vez de mayor tamaño y emplean decenas de miles de módulos en su construcción. Estos módulos sufren, desde el comienzo de su actividad, una degradación continua de sus células que hace disminuir su rendimiento y a menudo son desechados por las grandes empresas aunque no hayan alcanzado el final de su vida útil. Este proyecto estudia de forma técnica y económica la rentabilidad de la reutilización de los paneles fotovoltaicos de Silicio, con el fin reducir la inversión inicial de las instalaciones de autoconsumo fotovoltaico y de ofrecer una segunda vida a los módulos que resultan aptos para continuar produciendo energía.ABSTRACT: Electricity generation from solar energy is clean, affordable and renewable. For this reason, it has grown a lot during the last years and has become the third source of renewable energy generation in Spain. Photovoltaic power generation plants are getting larger and using tens of thousands of modules in their construction. These modules suffer continuous degradation of their, which reduces their performance. For this reason, they are discarded by large companies even though they have not reached the end of their useful life. This project studies in a technical and economic way the reuse of Silicon photovoltaic panels, as they are the most used at present, in order to reduce the initial investment of photovoltaic self-consumption installations and to offer a second life to the modules that are suitable for continuing to produce energy.info:eu-repo/semantics/publishedVersio

Use of autologous tooth-derived graft material in the post-extraction dental socket. Pilot study

The objectives of the present pilot study are to compare via CBCT the alveolar contraction suffered both vertically and horizontally between the control group and the group using autologous dental material (ADM), as well as to study the densitometric differences between both post-extraction sockets. A split-mouth study was performed in n = 9 patients who required two extraction of single-rooted teeth deemed suitable for deferred rehabilitation with osseointegrated implants. Two groups were formed ? a control group, in which the post-extraction socket was not filled, and an ADM group, in which the alveolar defect was filled with freshly processed autogenous dental material. Both dimensional and densitometric analyses of the alveoli were performed in both groups immediately after surgery (baseline), as well as 8 weeks and 16 weeks later. The mean height of alveolar bone loss was: VL (Control 1.77 mm, loss of 16.87% of initial alveolar height; ADM 0.42 mm, loss of 4.2% of initial alveolar height), HL-BCB (Control 2.22 mm, ADM 0.16 mm, p= 0.067 at 16 weeks). The mean bone loss of the vestibular width (VL-BCB) was much higher in the control group (1.91 mm at 1 mm, 1.3 mm at 3 mm, and 0.89 mm at 5 mm) than in the ADM group (0.46 mm at 1 mm, 0.21 mm at 3 mm, 0.01 at 5 mm, p=0.098 at 16 weeks). At 16 weeks, densitometric analysis of the coronal alveolar area revealed a bone density of 564.35 ± 288.73 HU in the control group and 922.68 ± 250.82 HU in the ADM group (p=0.045 ). In light of these preliminary results, autologous dentine may be considered a promising material for use in socket preservation techniques